Grazing problems with cows’ teeth

By Dr Clive Dalton

Looking at a cow’s teeth

When buying or selling sheep, farmers and stock agents always inspect the animals’ front teeth (incisors) to make sure they can eat pasture effectively.  It’s called ‘mouthing’ and standard practice is that sale ewes are ‘guaranteed in mouth and udder’ before the hammer falls.

Why don’t we take the same approach with cattle, as their teeth are equally as important?  The answer is simple; it’s too difficult, as wrestling with a cow to open her mouth to inspect teeth needs strong arms, and can be dangerous, even with her head locked in a headbail. 

You need to get her nose in a half-Nelson wrestling hold, while leaning back against the headbail gate with feet well planted, and even then her head can still move quickly and hit you in the ribs.  Horns are an added hazard.

You then have to force the cow to open her mouth, which is best done by grabbing the side of her lip with your closed fingers, on the opposite side from where you are standing. 

There’s a small gap between a cow’s front incisors and her back molars where there is only gum.  You can poke your fingers in there for leverage to open her mouth while pulling her whole head upwards, but care is needed!  If she opens her mouth quickly and your fingers slip back between her molars, they’ll be neatly guillotined off, and you won’t see them again to get them sewn on again!

To get a good front view of a cow’s incisors, you need to hold their lips open (which they don’t like) to check for teeth numbers, missing teeth, gaps, to check the gums around the teeth, the state of wear and especially to see how well the incisors meet the gum.  To do all of this at once, you need three hands or a strong assistant.

Harvesting pasture

 
 The cow has a long ‘prehensile’ (gripping) tongue which is designed to sweep the grass into its mouth, where it’s immediately grabbed by the front incisors and held against the top hard dental pad before being ripped off by movement of the head.  A dairy cow can easily make up to 36,000 bites per day when in full lactation and being fully fed. So the state of her front incisors is critical to doing all this work.

Digestion

Reticulum or honey-comb bag

 After biting off the pasture, it is mixed with saliva (100L/day for a dairy cow) and masticated (chewed) by the back molars before being swallowed into the rumen (the largest of the four stomach compartments) for the first time. 

After bacterial fermentation in the rumen, the grass is regurgitated back into the mouth in round boluses to be chewed for a second time by the molars and swallowed back via the reticulum (honey comb bag used for tripe) into the omasum with many leaves for finer grinding (called the Bible). Then it passes in finely ground form into the abomasum or fourth stomach for final acid digestion before it’s voyage down the digestive tract into the small and then large intestine.

  

Eating short pasture
 So the first harvesting stage by the incisors is easiest when pasture is long – at least 2500kg DM/ha. So for a cow to eat say 13kg of DM/day for its maintenance and production needs, it has to harvest 90-100kg of wet herbage from the paddock.

It cannot do this effectively when grass is short (below 1100kg DM/ha), and when forced to nibble like a horse.  Horses have both upper and lower incisors so can easily graze down to soil level.  If cattle are forced to eat down to soil level, it’s a major challenge and results in severe damage to their incisors.

Teeth damage in winter

How much soil and teeth wear in this mob?

This incisor damage happens too often during winter when cows are held at very high stocking rates to build up pasture for spring.  These conditions also force cows to eat large amounts of soil, which is not good for their digestion.  On pumice soils, the risk of incisor damage is even greater due to the extra abrasion of the teeth dentine from the pumice.

Teeth damage in drought

Incisor damage also increases in extended summer dry spells and severe droughts when there is little green feed available, and most of what is on offer is very short, dry and wiry dead stems which are tough to tear off even when they can be held by the incisors.

Damage when changing teeth

Cattle are born with 8 temporary milk incisors which are then replaced in pairs from the middle pair outwards at an average of 1.5, 2.5, 3.5 and 4.5 years of age. After about 5 years of age (called full mouth), you cannot tell the age of a beast by its incisors and can only guess based on wear.  Very old cows will have very worn teeth and may have none (called gummies) – but this is prone to great variation and error.

Note that these ages are general averages, and there’s enormous variation between individuals.  As the new teeth push the old ones out and this can pose problems when aging, so beware of this when mouthing a cow.

Gaps between teeth

A good set of incisors has no gaps between the teeth, as when gaps develop, grass gets down between the teeth and the biting action causes it to act as an abrasive – eventually making the gap wider and the teeth forced further apart.

 As the teeth get more spaced out, they are then more prone to becoming loose and being pulled out completely.

Eating supplements

Cows with worn, damaged or missing teeth usually have no problems eating roughages like hay or silage, as there is little initial biting to be done. Similarly they can eat dry concentrates with ease.

Buying beef cattle

Beef cattle are not the problem that dairy cattle are, as beef animals are not kept at high stocking rates and hence forced to graze down so low to the ground.  Even in droughts’ beef cattle can usually find enough long roughage so don’t have to eat down to ground level.

Buying dairy cattle

The big concern is with dairy cows when people may have to pay up to $3000 for top genetics.  At these prices, you don’t want a cow with broken or missing teeth, especially if you are a sharemilker depending on money from the bank to buy the herd.

So the message is if you have to buy a good cow (beef or dairy) to be a foundation cow for the future of the herd, it would be a very good idea to insist that she is guaranteed to have a ‘correct mouth’. 

If you cannot get this guarantee or don’t trust the vendor, then insist that you have permission to mouth all the animals on offer before purchase, as a beast that cannot harvest pasture effectively will have her production compromised.  A sound mouth on a cow is as important as a sound udder and teats, and cows are always sold with these guarantees by all reputable stock companies.

Buying cattle on line

When buying stock on line, especially older animals, it’s equally important to check teeth before purchase, as there is no guarantee, as when buying through a stock firm, that your money and the stock will be protected during the transaction.

Dairy industry changes

Dairy herds have increased rapidly in size over the last decade, and so has the change from herringbone milking sheds to large rotaries with in-line medication systems, so farm staff don’t see the condition of cows’ teeth each day as when orally drenching in the herringbone.

So the chances of cows in the herd with defective incisors will be much less likely to be noted.

Genetics

In sheep it’s well recognised that the shape and closing (occlusion) of the incisors against the dental pad has a genetic component, and rams are regularly inspected and culled for any defects, or with undershot or overshot jaws which are considered to be very serious inherited traits.

It’s highly likely that a similar situation occurs in cattle but it has never been investigated.  When bulls can now have thousands of daughters in herds all over the country, it would seem to be a good idea to give some attention to their teeth, especially when modern dairy husbandry systems at times of the year force cows to eat hard dry herbage very close to the ground.

Examples of teeth

Cows  using their tongues to sweep grass into their mouths

Full mouth of fairly good set of teeth

Cow in serous trouble for grazing.  Missing teeth and remainder worn away

Another cow in serious trouble with critical middle teeth missing

All teeth present but large gaps between teeth for grass to get stuck and increase wear

Full mouth but large gap showing

Four tooth cow with gaps starting to develop

Four tooth cow showing grass stuck between teeth

Good full mouth but top of teeth unevenly worn

Full mouth with grass stuck between teeth

Six tooth mouth with temporary tooth still in gum on right

Full mouth of badly worn teeth

Full mouth of evenly worn teeth

Full mouth of evenly worn teeth

Dr Francis William (F.W.) Dry – Career, Memories and Anecdotes

By Dr Clive Dalton

Dr Dry collecting wool fibres from a Drysdale ram at the
MAF Whatawhata Hill Country Research Station in the late 1970s

Francis William Dry

• Born at Driffield, East Riding of Yorkshire, 23 October 1891.
• Elder son of Frank Dry, master draper and his wife Mary Avis Corke.
• Known as William, attended Driffield Boarding School where awarded scholarship to attend Bridlington Grammar School.
• B.Sc. (Leeds) 1913.
• Honours in Zoology (Class 1) 1914.
• M.Sc. (Leeds) 1914.
• Awarded Carnegie Scholarship to visit research institutions in the USA.
• Married Florence Wilson Swinton, at Saginaw, Michegan, USA on 18 May 1921. Had a son and a daughter.
• From 1917-1921 served as assistant entomologist in Kenya.
• Awarded Ackroyd Memorial Research Fellowship at the University of Leeds in 1921.
• D.Sc. (Leeds) 1925.
• 1928. Appointed as Seniour Lecturer in agricultural zoology at the newly founded Massey Agricultural College, Palmerston North, NZ.
• 1929 established flock of hairy Romney sheep at Massey. Work finally reported in detail in 1955.
• Retired from Massey in 1956 and took up honorary fellowship in Department of Textile Industries at Leeds University.
• 1958 Hon Life Member of the NZ Society of Animal Production.
• 1961-62 specialty carpet wool production established under control of Massey College.
• 1963 Dry and his wife returned to Palmerston North where he continued his work on fibre types leading to his book in 1975.
• Hon D.Sc.(Massey University) 1966.
• Hon Fellow of Textile Institute, Manchester 1971.
• O.B.E. (1973).
• Fellow of the NZ Institute of Agricultural Science (1976).
• Died Palmerston North 1979.

'Daddy'
‘Daddy’: FW Dry lived and worked in the days of formality when from school onwards, we males were only addressed by their surnames. In some schools, girls got their surnames too, but more often these were preceded by ‘MISS’, said with cutting emphasis if they were in trouble.

So nicknames became very popular in this era – especially for much-loved and much-hated people we knew. So apparently in Dry’s early days he became ‘Daddy’ behind his back, but always Dr Dry to his face or if in the company of others. He never, ever said – ‘oh call me Francis or Frank or whatever’. He liked to be addressed as Dr Dry.

The term ‘Daddy’ apparently came from the fact that Mrs Dry always referred to him as ‘Daddy’, which he would have been called within the family made up of two children, Avis Mary who was a psychiatrist in Leeds, and David who was a photographer in Palmerston North. Both are deceased.

Dry referred to her as ‘Mammy’, or described her as Mrs Dry in conversations with others. She would never know that “Daddy’ became the name we all used, and which has now gone into the annals of agricultural and New Zealand history.

F.W.Dry Memorial Award
'This Award arises from a fund established in memory of the late Dr F.W. Dry, founding lecturer in Animal Genetics and Wool Science at Massey Agricultural College, and a member of staff from 1928 to 1956'.

Details: The F.W. Dry Memorial Award shall have a value determined each year from the interest earned on the capital and be open to all students undertaking a postgraduate degree or postgraduate diploma in animal science (papers with prefix of 117) at Massey University. The Award will be restricted to candidates specialising in animal breeding, animal genetics, or mammalian fibre science.

Dry’s famous publications

• Dry, F.W. (1924) . The genetics of the Wensleydale breed of sheep. I. The occurrence of black lambs. J. Genet. 14,: 203-218.
• Dry, F.W. (1926). The coat of the mouse (Mus musculus). J. Genetics, 16: 287-340.
• Dry, F.W. (1926). Colour inheritance in the Wensleydale breed of sheep. J. Text. Inst., 17: (30), 180-186.
• Dry, F.W. (1927). Mendelian breeding with Wensleydale sheep. J. Text. Inst., 18: (10), 415-420.
• Dry, F.W. (1928). The agouti coloration of the mouse (Mus musculus) and the rat (Mus norvegicus). J. Genetics, 20: 131-44.
• Dry, F. W. (1932). Some aspects of fertility in sheep. Proceedings of a meeting of sheep breeders, Massey College July 1932.
• Dry, F. W. (1933). Types of hairy fibres in the fleece of the Romney lamb, their identification and importance. Proc. of meeting of sheep breeders, Massey College July 1933, P 38.
• Dry, F.W. (1933a and 1934). Hairy fibres of the Romney sheep. N.Z. Jl. Agric., 46: 10-22, 141-53. 279-88: and 48: 331-43.
• Dry, F.W. (1933b). The pre-natal check in the birthcoat of the New Zealand Romney lamb. J. Text. Inst., 24: T 161-6: N.Z. Jl Sci.Tech., 14: 353-8.
• Dry, F.W. (1935).The early progress of the Romney lamb and features in the development of the fleece. N.Z. Jl Agric., 51 (4): 229-37.
• Dry, F.W. (1936). The genetics of the Wensleydale breeding sheep. J. Genet. 33 (1): 123-34.
• Dry, F.W. (1940). Recent work on the wool zoology of the New Zealand Romney. N.Z. Jl Sci. Tech., A22: 209-20.
• Dry. F.W., McMahon, P.R., Sutherland, J.A. (1940). A mendelian situation in the birthcoat of the New Zealand Romney lamb. Nature, 145: 390-391.
• Dry, F.W. (1952). The genetics and fibre morphology of N-type sheep. N.Z. Sci. Rev.5: 69-71.
• Dry, F.W.; Stephenson, S.K. (1954). Presence or absence of the prenatal check in lambs' birthcoats. Nature, 173: 878.
• Dry, F.W. (1955a). Multifactorial inheritance of halo-hair abundance in New Zealand Romney sheep. Aust. J. agric. Res. 6: 608-23.
• Dry, F.W.(1955b). The dominant N gene in New Zealand Romney sheep. Aust. J. Agric. Res., 6: 725-69.
• Dry, F.W.(1955c). The recessive N gene in New Zealand Romney sheep. Aust. J. Agric. Res., 6: 833-62.
• Dry, F.W. (1956): Twenty years of Mendelian sheep breeding. Proc. N.Z. Soc. Anim. Prod. 16: 130-140.
• Dry, F.W. (1958). Further breeding experiments with New Zealand Romney N-type sheep. Aust. J. agric. Res., 9' 348-62.
• Dry, F.W.(1965a). Lamb fibre types. In Biology of the Skin and Hair Growth. (Lyne, A.G. and Short, B.F., Eds). Angus and Robertson, Sydney, 89-104.
• Dry, F.W.(1965b). Mendelian sheep. Indian J. Genetics and Plant Breeding. 25:113-36. The late Professor Al Rae at Massey told me that he considered this paper a real 'Daddy' classic.

Massey College meetings
Massey University started off as Massey College to train agricultural graduates and farmers. Under their new Principal Geoffrey Peren (later Sir Geoffrey) they started farmers' meetings which became the Massey Sheep Farmers' as well as the Massey Dairy Farmers' Conferences which ran for at least five decades.

Below is the cover of a reprint from one of the first meetings in 1932, sponsored by Romney sheep breeders. From the signatures on the front, the reprint has belonged to R. Waters (an early wool scientist) and Prof Al Rae.

In Prof Peren's opening address he is warning farmers that the government's withdrawal of funds for the college will greatly restrict the research programme, as the four teaching staff will be overloaded. So he was asking for financial help from farmers. This has been a familiar tune over the years.


Here's an advertisement in the Proceedings for the College. The fees were fifty guineas per annum!


Dry's famous book

Dry, F.W. The Architecture of Lambs' Coats. A Speculative Study.
Massey University Press, Palmerston North, NZ 1975



The fly leaf contains the following information:

'Citing many facts and ideas from the following companions':
In Massey University

• F.R.M. Cockrem
• A.S. Fraser
• Nancy Galpin
• H. Goot
• Anthea Helford
• R.J. McIntrye
• P.R.McMahon
• Sundara Narayan
• Hazel Riseborough
• D.A.Ross
• Janet M. Ross
• K.M. Rudall
• S.K. Stephenson
• J.A.Sutherland
• G.A. Wickham
• G.M.Wright

In Leeds University

• Marca Burns
• R.A. Guirgis
• C.E. Nash
• J.A. Knott
• C.G. Priestly
• K.M. Rudall
• H.J.A. Side

Dedication
The book is dedicated ‘To the memory of Harry John Allan Side'.

On the back cover
On the back cover is Daddy's potted history in tiny print you need a lens to read.There is also his photo.
His Massey colleague Bob Barton told me what a difficult job it was to get it. Daddy didn't want a full-frontal mug shot of himself, so the photographer had a hard job to get a side view, resulting in Bob being in the frame.

Dry's acknowledgements
This is written in Dry’s classical English, strongly influenced by his Yorkshire precise and economical form of speech. Yorkshire folk waste nowt –especially words. As you can see, Dry loved commas, as they gave great moment to meaning - and didn't spend much on ink too!
To really appreciate it - read it aloud with a Yorkshire accent.

"Those to whom my thanks are due are far too numerous to mention, but my debt is a very special one to the small number now named. The ways of thought revealed trace very largely to my much mentioned Professor of Zoology, Walter Garstang, and my Professor of Botany, J. H. Priestley. The reaction to the universe of my Professor of Geology, P.F. Kendall, was very colourful and inspiring. He filled his science with mirth.

'If by work you mean doing something you don’t like,' he said, “I have never done a day’ work in my life.” In the lecture boastfully reported above I began by mentioning that early in my very first term the founder of the Department of Agriculture, (at Leeds) Professor R.S. Seaton, had told me to study Mendelism as new capital for livestock breeding. Professor A.F. Barker was my imaginative and inspiring host in the development of Textile Industries at Leeds from 1921-1928.

Three prominent farmers in the Manawatu whose co-operation has been of very great theoreticl and practical significance are Holgar Voss, N.P. Neilsen, and D.A. Scott. In the five years after my depart from what is now Massey University the fibre type work was substantially advanced through the hospitality of Professor J.B. Speakman in his Department of Textile Industries in the University of Leeds.

For many years this work was maintained by the support of the New Zealand Department of Scientific and Industrial Research, and it was through the backing of the former Director-General, Dr W.M Hamilton, and of the Vice-Chancellor of Massey University, Dr A. Stewart, that I was able to address myself to writing this book after the responsibility for exploiting the N-gene had passed to younger hands.

I am grateful to Professor T.L.Bywater, Head of the School of Agricultural Sciences in the University of Leeds, for the opportunity to add to and partly revise the script as a member of the organization in which my first piece of research was started. My stay there gave me several new glimpses of the fibre forests.

My colleague, R.A. Barton, has applied his editorial experience and eagle eyes to the final proofs. Besides matters of construction and convention, he has coped with serious errors, defective words, wrong brackets, and the stance of letters. He has cheerfully worn down a task several times as large as ever it entered my head to imagine."

Footnote (from Tim Johnston, Leeds)
Daddy refers to the Founding Professor of Agriculture as R.S. Seton, who, in fact, was the fourth Professor. The first, James Muir, existed from 1891 to 1896. When the East and West Riding County Councils (CCs) took a 30 year lease on Manor Farm, Garforth where Muir suggested that he should be manager.

The CCs of both Ridings set up a Committee to consider this and decided that not only should he not become the manager but that he should NOT continue as Head of the Dept of Agriculture. After a bit of a wrangle, Muir left in 1897 and became the Instructor in Agriculture for the Somerset CC.

Apparently at Leeds he did the minimum of lectures - in those days mainly 'out-reach' work but spent his time writing a textbook 'Agriculture - Practical and Scientific' 1895, and taking more professional examinations. He was MRAC when appointed but also FHAS, MRASE, PASI when he left.

His successor, Dr James Clark, was dismissed in 1898 for carrying on a business expressly forbidden by his contract with the Yorkshire College. It was subsequently found that his degree of MA, Edinburgh was false, as was his claim of a German PhD. Seton, a Scotsman, was eventually appointed, having applied when Clark was appointed and again on Clark's dismissal. Seton came from the Harris Institute at Preston.

Chapter X. Conclusion
The first paragraph again is classical Dr Dry.

“Fibre type details lend themselves poorly to summarizing. A series of mini-essays could resemble lectures that scratch too much ground. A peroration would have a phoney ring, My thoughts slip back to examinations suffered and imposed. Three procedures to my taste, though not often imposed were:

1. To invite the candidates to present scrappy notes, instead of continuous grammatical discourses.
2. To allow notes and books to be brought to the examination.
3. To let the victims answer whatever number of questions they chose.

As to the last, Professor J.H. Priestly explained it was not what they didn’t know that he wanted to find out, but what they did know. To round off this undertaking permit me to provide a series of questions to be answered under the above rules.

He Daddy goes on to present 14 questions. He ends the book with this paragraph:

‘Garstang became Professor of Zoology – as distinct from Biology- in the University of Leeds near the end of the first decade of the present century. Late in 1969 I enjoyed the fun of giving a lecture to the advanced students of Animal Husbandry in the School of Agricultural Sciences of my University sixty years and a few days after going up as a fresher. This was on work on sheep which traced in curiously numerous ways, mundane as well as fanciful, to Garstang.’


Copy in Leeds School of Agriculture library
His copy donated to the old Leeds School of Ag Dept Library has the following inscription:

'With my compliments and lively thanks to the librarians who looked after me in the years 1968 and 1969. Thereby, in my opinion, this story was improved considerably’.

Unsold copies at Massey
Dr George Wickham remembers that the book ended up as ‘the baby’ of Massey Vice Chancellor, Dr Alan Stewart as it was paid for by the University. The Massey Sheep Department were always very skeptical about whether it should be published considering it’s out-of-date technology. There were many copies left unsold.

Typical pages in the back with many pictures of his classified fibre arrays.

Recollections & correspondence ( From Lance Wiggins)
Although not a student of Dr Dry he treated me like one when I joined the NZ Wool Board in 1972. His first contact with me was the following letter which arrived shortly after I began my job in Wellington. I of course was flattered.
Kathleen (my wife) student-flatted in his house in Karaka Street in Palmerston North while Dr Dry was in England in the 1960’s.

(Dr Dry’s Letter)
5 Karaka Street
Palmerston North
New Zealand.
26.11.72

My dear Lance Wiggins
I’ve got to call you something not too formal. For I realize in a way we are related by marriage, two marriages. I understand that in the event of my grandchildren becoming orphans, your wife’s sister would become their guardian.

Concerning Tuki Tuki. After talking on the telephone a time or two, in the course of which I told Mr. Coop that husbandry considerations should decide the shearing date, he concluded that they should be shorn in the week now beginning. He thinks it best not to wait until the first week in January. Their coats are growing fast, and, too, he wants the second shearing not to be thrown too late. So I am to proceed to Tuki Tuki on Wednesday November 29th to sample the animals I sampled earlier.

Yesterday and the day before I was at a conference of the N.Z. Branch of the N.Z. Institute. Dr. Gerald Laxer (or the) Deputy Director of the I.W.S. spoke on The Future of Textile Technology. Looking ahead, over ten years, he said that he expects wool like Drysdale to be very much wanted ten years from now. Which, I take to mean, all the time between now and then, and afterward too.

I saw Dr. Don Ross at the same gathering. I hope you will be able to see him. Mr. Gemmell of U.E.B. was there, but instead of staying until the second day I discovered he had departed the previous evening. So not a word did I have with him.

At the same event I met two members of the firm of N.Z. Woolpacks and Textiles Ltd., Mr. A.L. Muir, “Plant Manager” and Mr. A. A. Wells, “Works Manager”. I learnt that this Foxton firm, by way of diversification, makes some carpet yarns, importing Scottish Blackface wool, material which does not greatly please them, for the hard core of their blend. About half of the yarn is exported, I think to Australia. Not surprisingly they would like some Tukidale, Cumberdale, Drysdale, if so it should be in memory of a former Chairman of the Massey Council.

There is a lot more I want to discuss with you. I will see if I can get you on the telephone in Wellington, on, probably, January 3rd, when we expect to hand this house back to our son.
Much happiness to you and your family in projected movements.

Kind regards,
“Ernest” Dry
Too little time to explain how I got that name.


Dr Dry visited me on several occasions to discuss his work and to ensure that I understood its importance and commercial significance. At the time he was very excited by Malcolm Coop’s “Tukidales” and suggested that I visit him. A very worthwhile visit with a very hospitable farmer.

My enduring memory is of Dry falling asleep in my office mid sentence and feeling terrified that he was dead - yet only two minutes later he woke to continue where he had left off. Most unnerving.

Because of our distant family connection we invited him home on one occasion to stay for the night. When he met Kathleen for the first time and learned that she was a primary teacher he gave us his philosophy on the worth of educators to society. His view was that primary school teachers had the most important and demanding job in education teaching the young to read and write while university teachers taught the more intelligent and able who wanted to learn.
He would reverse their positions and pay the primary teachers a professor’s salary and vice versa.


Hairy shaker disease (from Tim Johnson, Leeds)
I met Daddy Dry when he was visiting Leeds in Spring 1970. He was in the house in Lifton Place and one morning when walking in from Headingly he found a dead squirrel in the gutter at Hyde Park and brought it into the Zoology Department. He was surprised and disappointed that they were not interested in dissecting it!

One day Professor Bywater (HOD) asked me if I would take Dry to Knighton in Radnorshire so that he could visit farms and take wool samples from new-born lambs because Dry believed that the birthcoat fibres could indicate those with Scrapie.

We set off from Leeds in my new car with Mrs Dry (Mammy) in the back. Along the way I saw her through the mirror buttering bread to make a sandwich. I was not amused. We arrived at the Hotel in Knighton and the manageress appeared. Mrs D said 'Oh, it hasn't changed since we were here seven years ago'. Yes , said the manageress we haven't decorated anything.

She then announced to Mrs D – ‘you are on the second floor and Mr D is on the third’. Mammy D turned to me and said 'we have separate rooms because he sleeps with the window open and I sleep with it closed.

Dry had arranged for us to visit several farmers that were into their lambing season. It was a cold Easter time and we would get onto a farm in biting winds and the farmer would hold a lamb while D snipped of a few fibres and put the into a labeled envelope in his inside raincoat pocket.

These fibres would later be examined under a microscope to see the tips:

• Straight = Normal
• Curled = Scrapie.

He had battles with the Veterinary profession who poopood his thesis. One day at lunch, Mrs D said that she had been listening to the Government Medical Officer for Health at a Conference in Brighton who had said that anybody at 80 years old should be able to select euthanasia. She poked Dr D with the comment 'only two years Daddy'.

On the Saturday we were to return to Leeds, but I was staying near Burton on Trent so I took them to Derby Station. As we set off, Mrs D said that she needed a pint of milk (What, in the Welsh borders?). We suddenly saw a milk tanker so she said stop him for a pint of milk, please. I didn't

We got to Derby Railway Station at about 3-00pm and I thought where the hell can we find milk: she will have to get it at Leeds. However, I nipped out of the car and told them to get out with their luggage while I went into the street. Believe it or not, there was a milk float returning to its depot. I bought a pint, took it back and dumped it in Mrs D's lap! They went for the train and I went home.

The stuffed rooster (from the late Graeme Hight)
Daddy always used to come into the class to deliver his genetics lectures with a stuffed rooster under one arm and his yellowing notes under the other. He never did get round to using this avian visual aid. At least they all remembered that even if they forgot everything else.

Other old students remember that he always came to class with a stack of textbooks which he never referred to.

The dustbin on the bus (from the late Graeme Hight)
Daddy arrived at Massey University on the bus one morning with the dustbin under his arm. When it was pointed out to him, he then remembered that he meant to leave it at the gate to be emptied.

Cricket analogies (from Clive Dalton)
Daddy being a good Yorkshireman knew his cricket.When he was at Whatawhata we worked out that the carpet company UEB who had control of supplying Drysdale rams had been supplying heterozygous rams as well as homozygous ones. Using the heterozygous ones meant it took longer to product the real high quality carpet fibre.

I suggested to Daddy that he should contact the big cheeses at UEB and get stuck into them. His reply in his carefully chosen Yorkshire prose was:

‘No, No, I think not. When I retire, there were two things I swore I would no do – one was to step out of my crease, and the other was to hit the ball in the air’!

Dry at the NZ Society of Animal Production conferences (from Clive Dalton)
In the 1970s – 80s Dry was regularly attended the APS conferences and always sat in the very front row. At question time he would stand up not being able to hear that someone else had grabbed the floor.

He would sort of ‘unfold’ from his seat and always had the manners to half turn around to address the audience as he offered his ‘observation – not a question Mr Chairman’. It was regularly about when the work had been done 40 years ago (which the current young scientist didn’t know!) and how the answer was a lemon then too.

Once when chairing a session I stupidly handed him the microphone so we could hear his comments, and then had a hell of a job getting it back off him to shut him up. I was looking for the plug to pull it out.
‘Thank you Dr Dry, Thankyou Dr Dry, THANK YOU DR DRY’, didn’t seem to work! Lesson - never give Daddy the microphone

'I’ll just go and get Daddy for you' (from Boyd Wilson)
My closest encounters with Daddy Dry were in Palmerston North, perhaps 1972. I was then the NZ Farmer southern bloke (yes, bloody Aucklanders reckoned the Manawatu was in the centre of the South Island). Anyway, I think Daddy initiated the relationship when he confirmed what he proclaimed as a "new" hairy gene in Romneys in the Coop family flock at Tukituki, Hawke's Bay. I think it was Daddy who named the sheep "Tukidales." Can't recall details: I think they were confirmed homozygotes and they were good enough sheep, but suspect they soon became old news.
I can still hear old Mrs D's voice whenever I phoned to check on a fact: ‘I'll just go and get Daddy for you’.

I can’t find my bike anywhere (from Geoffrey Moss)
There were some great characters on the Massey staff when I was a student (part time) there over 1948-53 and Dr Dry, our genetics lecturer, was a real ‘absent-minded professor’. One night very late he knocked on my door and asked if I owned a motorbike, and if so, would I mind running him home? 'I must have come out from town this morning on the bus because I can’t find my bike anywhere,' he explained.

He was a respected academic and a likeable eccentric and we were all fond of him so I took him home on the back of my Harley with a heavy pack on his back.

Each evening he would go home with two big Winchester jars full of Massey water in his pack because he and Mammy Dry refused to drink the city's chlorinated water. He did this for years and everyone knew about it.

We had an oral and a written exam for the genetics final exams. In the written exam we were permitted to take in any books we liked, but the questions were so designed that books were useless. My oral exam was held late at night. When I entered, Dr Dry invited me to sit down. 'Tell me all you know about eugenics', he said, as he proceeded to pull out a loaf of bread, a bread knife, some butter and a pot of jam and have his evening meal.


Brown envelopes and black velvet (from Clive Dalton)
When ready for the field, Daddy always carried his set of gear in the deep inside pockets of his fading brown Gabadine raincoat. Any hope of it turning rain had long gone. His gear consisted of:

• One pair of surgical scissors with upturned points.
• A pack of brown ‘government’ envelopes held by a thick elastic band.
• Pointed tweezers.
• A piece of black velvet about 6 inches square to put on his knee to show up white fibres for inspection.
• Small lens.
• A sandwich

His headgear was either an English style cap or a gamekeepers helmet with side flaps to tie under his chin if things got really rough.

A fibre waiting for an array (from Clive Dalton)
When at Whatawhata, we gave Daddy the full run of the wool lab to examine the samples he’d collected for the station’s Drysdale rams that day. Here he had more black velvet laid out as well as the contents of the brown envelopes, all with information in his spidery handwriting.

I went to the station one evening and saw the lights on in the lab and there he was sorting his fibres into his famous ‘arrays’. He had one fibre in a pair of tweezers when I went in and he held it there for at least half an hour of our discussions. I sort of followed him around the lab in our chat and he never let go of the fibre. I bet he knew into which ‘array’ it fitted - probably one of his favourite ‘Super sickle fibres’.

N type sheep as lawn mowers (from Clive Dalton)
The Massey Sheep Department under Prof Geoffrey Peren got tired of Dry’s hairy rams on the farm and they came under threat of slaughter. At that time, Peren was driving research in the crossing of the Cheviot on to the Romney to develop a more productive active sheep for hard hill country. The result in time became 'the Perendale' breed.

Dry was strongly advised to find his sheep, especially the rams a new home. Daddy solved the problem by farming them out to his friends in Palmerston North who tethered their allocated sheep to graze their lawns or back sections. If they had all gone to the butcher, the Drysdale and its great contribution to the New Zealand carpet trade would never have happened.

A brand new Raleigh 20 (from Clive Dalton)
When Daddy finally came back to New Zealand from Leeds, by then well into his 80s, he must have gone ‘right daft’ for a Yorkshireman who was always canny with his ‘brass’ . To everyone’s amusement and amazement, he bought a brand new Raleigh 20! This bike with its small wheels, low crossbar and good sound carrier was 'top of the line' at the time. Everyone commented that Daddy clearly had no intentions of giving up the struggle for a while yet, which was true.

None of the recorded anecdotes ever mentions Daddy driving a car.


Ruakura Farmer's Conference. Hairy genes in New Zealand

Drysdale staple from one-year fleece

When we started a Drysdale flock at the Whatawhata Research Station to be included in our breed comparison trials, we gave a paper at the Ruakura Farmer’s Conference which was published in the 1973 Conference Proceedings. Here are some bits from it:

DC Dalton, ML Bigham and LK Wiggins.
Special Carpet-wool Sheep.
Proceedings of the Ruakura Farmer’s Conference, 1973. 21-33.

The N gene

Drysdale rams showing the hairy fleece and strong horns

This gene was discovered in a Romney ram by Dr Dry in a flock owned by Mr Neilson of Palmerston North; hence the symbol N given to it by Dr Dry. Dry worked out the basic inheritance of the gene over a period of years and its action is now fairly clearly understood.

The two most important features of the N gene are that it is almost completely dominant, and it influences the lamb birth coat as well as the adult fleece. It seems essential to a successful hairy sheep-breeding programme that all breeders should be familiar with the classification of lambs’ birth coats, and should include birth-coat classification into their basic flock recording.

The horns on the Drysdale increase management problems, but as yet no effective solution has been found to banishing them either by genetic or by non-genetic means. Few hairy sheep in the world appear to be free from horns.

The T gene

Dr Dry with what we think is a Tukidale.
Photo from Te Ara Encyclopedia of New Zealand

This gene was discovered by Mr M.W.Coop of Tuki Tuki in Hawkes Bay in 1966 in a hairy ram lamb which had been reared as a pet lamb. It was found to be a dominant gene (called T after the farm) which caused complete hair cover especially in the Tt sheep.

There were no apparent birth coat variations with the T gene as with the N gene. This makes identification of genetic makeup impossible without progeny testing. Because the fleeces of the heterozygous Tt are completely hairy, the transition form ordinary wool to a specialty carpet wool is achieved in one cross.

Horns are linked with the hairy fleece as with the N gene, except that all the Tt ewes have short spiky horns and the rams have heavy horns. Performance traits of the Tukidale are similar to the Romney.

The K gene
Professor K.B. Cumberland and his son Garth obtained two hairy rams and seven hairy ewes from a Mr L. Johnstone at Te Puke. Some hair sheep from this farm were also transferred to the property of Mr B. Johnstone of Kamano near Cheltenham. Initial test mating were carried out by the Cumberlands in 1972 to see if the sheep were carrying a dominant gene, and the results indicate that they were. The named it the K gene.

Mr B. Johstone considers that the K gene is the same as the N gene but Dr Dry has found no evidence to suggest that the K gene differs from the T gene and is firmly convinced that the K and T differ from the N gene.

These sheep and their progeny are now being used to breed a new carpet-wool breed based solely on Perendales which have high fertility, open faces, easy-care traits and fleeces of low lustre and high resilience. Carpet sheep derived from the N, T or K gene mated to high-fertility Perendale ewes are to be called 'Carpetmasters' and will be designated Carpetmaster N, T or K depending on what gene is present.


The B gene
In addition to the K gene, the Cumberlands have also found the B gene which Dr Dry considers to be different from N, T and K genes. The gene originated from a southern Hawkes Bay flock in 1972. The ram had a very low fleece weight and though his progeny have not been shorn as hoggets, they appear to also have low fleece weight which could eliminate this gene from commercial use.

There is some evidence however, that this sheep is producing wool similar t that produced by Indian carpet-wool breeds. This wool is comparatively fine and very highly regarded by the trade.

Drysdale breeding
Dr Dry worked all this out in his work at Massey. It’s the classical ratios ‘discovered’ the famous Austrian monk, Gregor Mendel in his garden where he grew sweet peas – subsequently called ‘Mendelism”.

Generations of students have been put off animal breeding by having this information hammered into them by lecturers who didn’t seem to realise it had little application in large animal breeding – unless you were breeding Drysdale sheep or the horns off cattle!

This was the notation used for the genes at the time:

1. (NN x NN = all NN).
This is the Drysdale crossed with a Drysdale. Both parents are homozygous with the dominant allele ‘N’.

2. (nn x nn + all nn).
This is the Romney x Romney which gives all Romneys. Both parents are homozygous and have the recessive allele ‘n’

3. (NN x nn = all Nn)
This is the Drysdale x Romney where all the offspring are heterozygotes.

4. (NN x Nn = 1NN: 1 Nn)
This is the Drysdale crossed back across the heterozygote to give straight Drysdales and heterozgotes in the ratio of 1:1.

5. (Nn x Nn = 1NN: 2 Nn: 1nn)
This is crossing two heterozygotes which produces all three types, straight Drysdales, more heterozygotes and straight Romneys, always in this 1:2:1 ratio.


Updated symbol for alleles (From Dr George Wickham)
Information produced for article in NZ Black and Coloured Sheep Breeders Association publication, 19??. This shows the updated terminology the COGNOSAG (Committee on the Genetic Nomenclature of Sheep and Goats). Dr Wickham adds that things will change once gene mapping advances further knowledge.

The Drysdale arose as an offshoot of the Romney. In the 1930s some wool manufacturers criticised Romney wool as being too hairy for their products. As part of a research program into the problem a flock of sheep with extremely medullated wool was selected and studied. By the 1950s these sheep had been intensively studied from a genetic and a wool growth point of view.

The descendants of two of the original rams introduced into the flock were shown to have a semi-dominant gene (initially named N, then Nd , later HH1N ) and the wool of these sheep was like that of the Scottish Blackface, a type needed as part of the wool blend for some sorts of carpets. At this time there was a shortage of this type of wool and, at one stage, Blackface wool was selling at a higher price that average Merino wool. HH was the code for High Halo Hair.

During the 1960s, commercial flocks of Drysdales were established by mating rams homozygous for the N gene to Romney and a few Perendale ewes. Lambing performance of the flocks which have descended from these have tended to be like that of Romney flocks. Initially there was a marked advantage in terms of profits from wool. Although still tending to be slightly in favour of the Drysdale this advantage declined as numbers and total wool production increased to the point where supply more-closely matched demand. Another factor in this equation is a tendency for most manufacturers of wool carpets to now use fibre blends that contain less medullated wool.

Most of the sheep we farm have been selected for a type of fleece in which all fibres are relatively similar in size and nature. In contrast a Drysdale fleece is a mixture of fibres which can differ markedly. About 25% by numbers are medullated (hollow). Some of these are kemps which only grow for a few months and moult when a new fibre starts to grow. These tend to be over 100 microns in diameter and 50-100mm long (unless cut at shearing).

Other medullated fibres are finer (50-90 microns) and grow continuously (about 20mm per month). Most (in terms of numbers but not weight) are finer still (15-45 microns) non-medullated and continuously growing (about 10mm per month). Thus the mean diameter (micron) used to classify other types of wool is meaningless in Drysdales.

Two similar breeds first arose in New Zealand but are now only found in Australia. The Tukidale was developed using another, more-dominant, allele at the N (HH1) locus (HH1T). This was found in a Romney flock. The Carpetmaster breed was developed partly from descendants of a carpet-wooled ram found in a Border Leicester x Romney flock. This ram carried a gene at the N locus that might have been identical to the gene in Tukidales. Sheep carrying the Nd were also introduced into Carpetmaster flocks.

Memory: Dr Doug Lang when at Massey as students spent quite a bit of time helping Doc. Doug and I used to go off together with Dr Dry on our push bikes. We developed a technique to allow us to get home before midnight when it came to culling etc.

One of us would read the sheep's ear tag and then we would leave him to mull over his thoughts (talking to himself and maybe us) for 2-3 minutes, and then we would make the decision for him on the basis of what we had heard. If we left him to his own thoughts it could take half an hour for one sheep.

Looking back, what was Dry's contribution?

A memorable photo I took at the Whatawhata Hill Country Research Station in the early 1980s.
Stockman Ian McMillan holds a Drysdale ram, and Dr Murray Bigham is doing the recording for Dr Dry.

From Dr George Wickham
I suspect Dry's main contribution was interacting with graduate students. Some of the early Massey graduates had a pretty significant effect on New Zealand, Australian and UK animal production, and Dry probably had a significant effect on their thinking.

Ted Clarke and Al Rae, although only partly with him, were instrumental in sheep and cattle breeding. McMeekan's early papers on pig genetics suggest a Dry input in his graduate research.

Of those working on wool directly with him, Nancy Galpin extended our knowledge of follicle development, went to work with Wildman at Torridon in Leeds but didn't continue. Pat McMahon did a great job in Australia straightening out thinking on the relationship between wool traits and processing, and Don Ross extended this in NZ.

I think the mouse hair growth paper probably was his most important research. It really set the scene for a great deal of subsequent research on hair cycles in other species and the control and onset of different phases. The lamb fibre type studies have been unrewarding and if the same time had been put into other studies, that time might have been better used.

The work on the genetics of the Drysdale had a pretty big effect on the viability of carpet manufacture in NZ at a time when carpeting and carpet yarn was difficult to market unless it contained about 10-20% of medullated wool. If the manufacturers had continued to get their medullated wool from UK (often very poor stuff), they would not have lasted as long as they did. I suspect the farmers did not do as well out of the Drysdales as the processors did.

Dry got very obsessed with fibre type work and why he didn't move sideways to examine the validity of some of the theories he hatched needs to be considered.

I guess his training in Zoology at a time when Zoology was an observation and classification- based science with little experimentation was a major factor. It seems likely that his move into Mendelism was a little late and he never developed good skills in experimental design.

Also, while he encouraged post-grad students to approach new people in other fields and to broaden the techniques available to them, he did little to try new techniques himself. Despite being a great conference attender in New Zealand, he was fairly introverted, and this might have been a factor in his reluctance to move outside his comfort zone.

Memorial to the Drysdale
All that remains of the many Drysdale flocks

Introduction to Practical Animal Breeding

Clive Dalton's latest1980 Practical Animal Breeding textbook - is devoted to providing a pragmatic person's guide to the sciences of animal breeding, genetics, population genetics, basic biology and Mendelism, with examples and case studies of their application in agriculture, farming, animal production, and livestock improvement.

Detailed information is provided on the practical application of scientific theories for breeding and selection decisions, breeding methods, breeding practice, breeds, breed structure; with a focus on cattle, sheep, pigs, and poultry.

As a student in the early 1950s at King’s College, University of Durham in Newcastle upon Tyne in the UK, I developed a great interest in animal breeding.  Those were the days of text books which we students revered, and they were relevant for decades.

I also worshipped my Kiwi Prof,  M.M (Mac) Cooper who did more for practical animal breeding in UK than anyone before or since.   After my PhD in sheep breeding in North Wales, I went on to teach animal production at Leeds University and do breeding research with laboratory mice. Farm animals were not available which had many advantages in terms of quick turnover of generations.

So by this stage I had seen every textbook on the subject and had ‘tried’ to read them all. They would have made a stack about a metre high and the vast majority of them although editorial masterpieces were terrible to read.

They all started off saying the book was designed for students, and some would even add farmers to the intended audience.  All went well for the first chapter or maybe two, until you hit Mendel and his peas.
Then soon after this, you hit algebra and calculus, and that was the end for most folk who were desperate to know what to do after you had the sheep into the pens, or the cows in the yard. Then what?

How did you sort out the best ones for breeding and the worst for culling?  Students rarely got to this point, and even if they did, they were so switched off by Mendel and algebra that they gave it all away.

Lecturers killed animal breeding for most students.  Having suffered the pain of listening to hours of this as a student, and being very conscious of the pain I inflicted on my students when covering the syllabus to get them to pass exams, frustration motivated me to try to keep things simple.

When I moved into animal breeding research in New Zealand, I really enjoyed the relief of not having to bore students to death any more with genetics and animal breeding.  It was over - so I thought.

Then as our research developed, we had regular groups of farmers and university students coming to the research station to see what was going on, and asking not just the ‘what’ questions, but the more important ‘why’ ones too.

We initiated large scale breeding schemes with 280,000 sheep and 16,000 beef cattle where the staff involved wanted to know the background theory to the programmes.

So I was back in the business of explaining genetics and animal breeding all over again - but this time, the ‘students’ couldn’t get enough of the subject, and drove us to exhaustion with their searching questions.  It was an incredibly rewarding time.

So this book really came from those years. It was written in 1980 and a lot has changed since them in the high-tech end of genetics, and with computers having so much more power to analyse massive amounts of field data.  But not much has changed down at the sheep and cattle yards where we are still looking for the best stock, and deciding what  to mate them to, to bring about improvement.  The book became a recognised text book in English speaking countries and was translated into Japanese and Spanish.

0.2 - The Dalton Multipurpose Statistic

0.2 – The 'Dalton Multipurpose statistic'

By Dr Clive Dalton

Cranking handles in the 1950s

As a student in the 1950s, we did statistics labs on small Brunsviga hand-cranked calculators with tiny levers pulled down to select the numbers wanted. You cranked the handle clockwise until a bell rang (I think when dividing), and then cranked it anticlockwise for a reason I’ve forgotten.

In a class of 20, you could not tell when your bell had rung!

Then for my PhD at Bangor University, the Agriculture Department had one electric Facit machine shared among students and staff. Inside it was a mass of robust little German cogs that whizzed around when you pressed the keys. We thought it was magic, and I pounded it for three years without problems. When I finished, there were rumours that the University was about to get a ‘computer’ to take up the entire space of an old chapel.

The computer age -1960s

In my early lecturing days at Leeds University, the Facit and American Marchant machines (see the interior of a Marchant XL at left) with a massive bank of keys ruled supreme, and were hammered by students for their projects and higher degrees.

A computer had arrived at Leeds and filled a retired church hall, and some of us started to learn to program in a mystery language called Algol, and then punch tape to get simple exercises done that took as long (if you added our errors) as using a calculator.

But our kids loved the reels of error-ridden punched tape that I took home after my failed forays into computing.

What did the end value mean?

The point was, that by the time you got to the end of a calculation, and you hadn’t botched things up a few times on the way, so had to start all over again, you were far too exhausted to think much about what the final values meant. Did they make any sense? Were they of any practical use?

Statistical magicians

When I went into full time research in New Zealand, I started to have suspicions about statistics because we had very bright professional statisticians to give advice at all stages of projects – in my case animal breeding trials. This was both interesting and frustrating.

When the statistician had ‘run your data’, and the miles of ‘line flow’ paper spewed out of the research station computer (that filled a whole room), you needed to go into a scientific trance to work out how to get ‘the results you wanted’ – so the imagined published paper would blow the scientific community away and you would be for ever famous! It was here the statisticians came into their own.

What you wanted?

It was wonderful if the results (explained by the statistician) confirmed your preconceived expectations (which you were not supposed to have), or if you were positively surprised with them. In other words you didn’t expect those results but you would have not trouble getting them published.

What was really bad news was when you were negatively surprised, as when the results went the opposite way to what you wanted and you couldn’t explain why – and would be lucky if any journal would publish the results.

The real pits were when after years of work, you got no result at all, and there was no way you could claim this as a ‘positive surprise’ that was publishable.

Hazards of long-term trials

In long-term trials, we could easily have the services of two or three statisticians as they came and went to further their careers. This could be really nasty as a newly-qualified statistician fresh from University with all A++ papers, would look at the analysis and ask why his predecessor hadn’t used the new XYZ package? It was inevitable that the new chum recommended the whole years of data be reanalyzed –his way.

The other statistician’s comment to bring on a sweat was ‘oh that’s interesting, I wonder what would happen if we put the data through the new ZYX package? I’ll give it a go’.

As the years went on, I found it hard not to scream – ‘for hell’s sake, just leave things alone’, as what came out of these packages became more and more unintelligible, and harder for us oldies to work out what it meant in practical terms. Statistical significance at different levels of probability to prove the null hypothesis was one thing, but making farming sense was very much another.

The trick was to feign knowledge of what all the statistical analysis meant. At times the blank pages in the line-flow printout were the most useful part of the output - for the kids to draw on!

Delays, delays

You knew that extra analysis meant delays in publication of a paper by at least another 12 months and sometimes more. They also meant more questions from editorial committees, whose job you very soon realised were a pack of nitpickers and/or jealous colleagues hell bent on stopping you publishing and having more published papers than they had. In a world of ‘publish or perish’, these antics didn’t help your next application for advancement with the research director.

0.2

So it was in this environment that I realised the value of 0.2 and claimed it as my own ‘Dalton Multipurpose Statistic’. This simple little value has four massive advantages, that I strongly recommend to you:

1. It is extremely versatile.
2. It is non-confrontational.
3. It can be grossly misinterpreted without causing serious harm.
4. It can bring relief and satisfaction to the needy.
   

Correlation coefficients

These are values that tell you how much one thing is related to another, and their interpretation is more abused that anything else on the planet.

• If you need a low correlation coefficient, then 0.2 can be called “low” and will support your case.
• If you need a “low and non significant” correlation to suit a case, then all you need are the numbers of observations (n) below about 60.
• Getting rid of observations is not difficult as there are plenty of reasons to classify values as ‘aberrant’. Animals die, they get pregnant before they should, they give birth before they should, they change sex half way through trials, and so on.
• If on the other hand you have a desperate need for things to be statistically significance at say r = 0.2, then increase the number of observations to over 100, and significance will be easily reached at 5% probability (P<0.05) which is respectable.
• The fact that it is “statistically significant” carries the day, rather than its probability, and not the fact that its practical implications may be total nonsense.
• Squaring a correlation coefficient (r²) should be avoided, as this can so often show how meaningless a correlation coefficient can be.
  

Repeatability and heritability estimates

Repeatability measures how things keep appearing and heritability is how strongly traits are inherited.

• If you need a ‘low’ estimate of either estimate, then 0.2 can be called low.
• This would be, for example, to show breeders that they were wasting their time in selecting for what they thought were important traits. In this case 0.2 could also be called ‘very low’.
• If however you needed it to support your own research, or a new trait that you wanted to claim a reputation from such as:
  

(Muzzle width/teat length) x √heart girth

then a repeatability and heritability of 0.2 could be squeezed from a ‘low’ into the ‘medium’ classification.

• Once it is into the “medium” group – then it can be squeezed into the “medium-high” group.
• Thus ‘low’ could be 0-0.19; ‘medium’ would be 0.20-0.40.
  
• Now 0.4 is really getting ‘high’, so 0.20-0.40 must be in a ‘medium-high’ group. You have created a winner - if that’s what you wanted.
  

Genetic and phenotypic correlations between traits

Again, these are values that tell you how much one thing is related to another. The genetic ones are about what’s inside the animal and the phenotypic ones are things you can see on the outside of the animal.

• Again 0.2 is very valuable.
• If you need a value to support a case, especially if you don’t know or can’t remember the actual value, or if you don't have one and need one, adopt the following rule:
• If you feel unsure or your job or reputation could be under threat, then use 0.19-0.20.
• If you feel confident, then really go for it and use 0.20-0.21
  

General percentages

• Whenever you need a percentage, 20% can be used with enormous confidence.
• If for example you need to show that a major fact is of minor importance, (e.g. the number of geneticists who have not written up their lifetime work), then 20% can be interpreted as small. This will take the heat out of the discussion.
  
• However, if you need to generate some heat, (e.g. to highlight the percentage of geneticists who are homosexuals or atheists, or both), then you can make 20% sound deliciously high!
• The 20% statistic is of course, the core of the 80:20 rule, which has certainly stood the test of time. You can use this rule for anything that comes to mind where you need to prove that 80% of something is caused by 20% of something else.
• Some visionary must have carefully researched this rule, who could see that the 20% part of the ratio was the clincher and would never be questioned, Have you ever met anyone who questioned it?
• If you do meet anyone doubters, simply drop it to 18-20%. If you feel cocky, raise it to 20-25%. But don’t every push it up to 20-30% as the ice gets too thin.
  

General Correction Factors

These are things that are used to get people to believe that mountainous playing fields can been made level by a bit of mathematical manipulation. A better name for them would be ‘Fudge Factors’. Geneticists need them all the time - described below.

• The effects on an animal of both Genetics (G) and the Environment (E) is the big worry.
• E can make a real fool of all your pontifications about G, as there are so many variables involved in the environment.
• But we love these variables, as it can so often save our bacon, especially in arguments with farmers where we use the trick of telling them what they know already, and that the problem is complex. By using the word ‘multifactorial’ – you can sound as if you know what you are talking about!
• You always need to find a plausible reason (excuse) why your years of work and money spent have resulted in a lemon.
• We also have to deal with what is called the ‘G x E interaction’ which is great fun where some animals do well in one environment but not in others. It adds delicious complexity to the situation – which only a host of fudge factors can help disguise.
• So here again, good old 0.2 is comes to the rescue and is perfect for the job.
  

Standard errors and standard deviations

These are tricky things to explain. You use a standard error (SE) to describe how accurate a mean is because of variation around it, and a standard deviation (SD) to describe the variation in a range of data. This is what they used to be anyway!

• 0.2 suits most needs and can be used freely if you do not have one of these statistics, or you forget to work one out, or especially if you don’t really understand what they are.
• Such is the case of a “residual standard error” which few ever knew that they were - 0.2 is ideal.
  
• The ± symbol which appears before these values fools most folk, as they are not sure what it is so move on searching for a heading that says ‘summary’ or ‘conclusions’ or both.
• Have no fear that 0.2 will get you through most editorial committees, that because of their age will ignore statistics because they won’t understand them.
• And the real coup is that they won’t dare to admit it, and stoop to ask some young smart whipper-snapper what it all means. The young always had learned from the old, and never vice versa.
• These old codgers could concentrate on checking if the author had written “data is” instead of “data are”, and if their name was in the list of references.
  

Missing values in a matrix

A matrix is a mass of little squares (cells) with figures in them all joined together in a big table with headings along the top and down the side.

• You need a matrix to show the relationships (correlations) between a host of things, and in all their possible combinations.
• You can’t have empty cells as it looks bad.
  
• It also risks putting a stop to your entire work, as some greater being will declare that things will have to wait, ‘until more data become available’. This is the kiss of death.
• All the meetings you have been attending for the last 18 months or more (expenses paid plus fudge factors) to finish the project will end.
• Never fear though as here again 0.2 can come to the rescue, simply because it can be used with confidence and without causing serious problems – at least problems where you could be blamed for.
• The reason why you don’t need to worry is that there are so many errors and generalities in a matrix that a dusting of 0.2s in empty cells won’t cause any serious damage to the outcome.
• But don’t put 0.2 in every empty cell. Break it up a bit by putting 0.19 in some and 0.21 in others. It’s not prudent go outside this range.
  

Acknowledgements

I have to thank many colleagues over the years, some of whom were distinguished geneticists and statisticians, for stimulating my thoughts in smoke-filled rooms, confirming my fears and excitement about 0.2.

The punched tape the kids loved.

They could throw the role and it would unwind for miles.

The boxes were very useful too.

I owe special thanks to Chris Dyson, Biometrician at the Ruakura Agricultural Research Centre when I worked there in 1980. Chris bristled with Yorkshire wisdom and common sense, and drew my attention to the fact that if you ever needed ‘a number’ - for anything , then 153 was the one to go for.

Chris pointed out that if you take the reciprocal of the natural logarithm of 153, this comes out as 0.199, which rounds up to 0.2. So there’s the magic 0.2 coming to the surface again for air and respect. It’s magic. QED!

Thanks also for comments by Dr Harold Henderson, veteran statistician at Ruakura whose statistical skills were only eclipsed by his patience with non-mathematical scientists like me.

I must also credit a wonderful website where images and information about old calculators abounds - http://www.oldcomputers.arcula.co.uk/calc1.htm#marchant_xl