Cows, calves and veterinary: October 2007

Breeding - as hard or as easy as you want it to be

Sensible farmers in NZ use a team of elite bulls selected by LIC. Draft the in-season cows, decide which breed to mate them to, wait for the technician to come and inseminate them and off they go to pasture.
LIC selects the 'bull of the day' and provides the fresh semen to the technician, along with a nifty little handheld computer that will tell him if a cow is at risk of being mated to her own father or brother - in which case, he will select the next day's bull or one from his stock of frozen semen.
What does the farmer get? Guaranteed conception rates (the technicians are well-trained and experienced, the semen preparation technology the result of decades of research and use), the best genetics in the country, a cost-effective option and minimal stress. All he does is identify in-oestrus cows and draft them.

I decided that wasn't good enough for me. What's more, this year I dispensed with the experienced technician. Because I'm not trying to achieve a herd of average cows - I already have a herd of average cows, and some of them are perfectly adorable. Nor am I overly enthused by the criteria by which the 'best' bulls are chosen. Less of an issue is the problem that a few people have pointed out, that a small number of bulls command the majority of inseminations. The Premier Sires team isn't small by any standard - without checking, I think there are about fourteen bulls of each breed employed - but when you consider that those bulls sire the majority of dairy calves across New Zealand, can stay in the team for years (Collins Royal Hugo, per example) and that the few farmers who don't use Premier Sires are most likely to choose those same bulls - there's a definite reduction of genetic base going on there, compared to the number of bulls proven and available each year.
When selecting which bulls I would use this year, I went to the internet and printed out the three-generation pedigree of those bulls. What I discovered was that two of the Jersey bulls were cousins to the third, and all three were third cousins of each other. Unsure whether I'd simply picked unwisely, or if this would be the case with any within-breed random selection, I mentioned it to the district manager, who agreed that because so few bulls were widely used, the genetic base was this narrow.
To cut a long entry short, Premier Sires doesn't meet what I'm trying to achieve in my herd. The 'perfect' cow is a lot of things. She's a good producer, healthy, long-lived and sweet-natured. I have also decided that she's medium-sized, has oodles of hybrid vigour and a well-supported, even udder.
A large number of my cows are already perfect. An equally large number aren't. my programme to create impriovement where imperfection exists, and maintain perfection, is sufficiently complex that I warned my technician in advance last year that I was matching individual cows to individual bulls and it was possible that he would have to inseminate seven cows to seven different bulls.
He agreed that I had every right to demand that. But he obviously didn't like it - for good reason. Simple, it is not.
So I trained up to inseminate my own cattle. Time consuming it is, but I do find it simple - the bulls are matched in advance and all I have to do is make sure the right straw goes into the right cow. Since I only have eight bulls in the AB bank, I know exactly where to find each and so far my system of keeping each loaded inseminator idenitfied has only failed once - the day I didn't check the colour of straw before inseminating a cow and realised before doing the next cow that the bull left was totally inappropriate for her.

Let it not be forgotten that through selective breeding, our modern dairy cow was created from a source that would have been totally unsuitable for bringing into a herringbone and cupping up.

Bos primigenius

148 is one of my favourite cows. She's nine years old in the image below (ten now) and has everything I like about a dairy cow - a quiet nature, good udder, longevity, production and she gets in calf to AB.

Everyone loves Giant Panda, but I dread the day she collapses with milk fever, hopefully at least four or five years hence:

She's four years old now, a daughter of Hailstone and I can no longer look over her back. A wonderful nature, but very out of place in my herd - with an udder to match her size, she takes twice as long as Mrs Average to milk out.

So I start with the list of bulls Alpha Jersey and from the sires offered in each breed, select the ones with breeding values that meet my goals. It doesn't take long - I need three breeds to maintain the ultimate in hybrid vigour. LIC only offers three Brown Swiss bulls, I e-mail them to get their proofs and selec tht eone that looks best and isn't overly expensive. Going through the Holstein Friesians, everything with a calving difficulty score higher than a three gets a big x against its name, as does anything with a high score for stature (the two traits are linked). Much as we love Giant Panda... (also, the quickest way to improve fertility in my mind is to minimise dystocia at calving).
In all breeds, very poor management scores, fertility scores, udder scores get that big x. By the time I'm done, there's not a great many bulls to choose from - and it's worth noting that most of the bulls in the Premier Sires team will have the veto mark against them.
With the vetoes out of the way, I select for medium size, good farmer traits, fast milking, low SCC, high capacity, good udders (front teats not too wide, well-supported). Just keeping an eye on production, BW, feet and legs, genes (lethal genes usually a veto, especially since I can't use the inbreeding and lethal gene warning computer programe that technicians have). Shorter gestation length is a bonus - more days in milk plus an increased chance of getting in calf the following season.
That's the bulls out of the way - once selected, I'll look at their pedigrees and then draw up a quick chart of their strengths and weaknesses - for corrective mating. Hence, if I have a cow with a poor temperament, low production or udder problems, I've got a few choices concerning her progeny. I can mate her to beef. I can mate her to any old bull of the desired breed, and hope the genetic combination is a positive one. Or I can selectively mate her to a sire who throws daughters strong in the trait she is weak in.
The space between calving and mating is long enough to assess a cow, remembering always that she is being assessed on phenotype - her actual genetic make-up could surprise you. LIC has a programme that will do this for you - at a cost. I just make a list of the cows in the herd and against each cow I note her breed make-up, BW and any specific positive or negative traits. Her 'optimal mating' is selected on the basis of maximising a)easy calving for her next spring, b) hybrid vigour in the progeny, c) perfecting her phenotype as expressed in the progeny and d) maximise BW and e) goes along with b - check up on her ancestry to avoid in-breeding. Outcrossing ot a different breed is enough to prevent this, but there are several occasions where inbreeding is a risk - primarily the heifers who, for easy calving, are always mated to a Jersey bull in their first year in-milk. The combination of a same breed bull and a similar age range between young cows and newly-proven bulls makes an in-breed not unlikely.

Once the decision is made, all that's left is to apply semen to cow, cross fingers and hope for the best. The results won't be known for another three years - when the progeny themselves calve and enter the dairy herd.

And I found this fun link too, just in case four breeds isn't enough to capture the imagination:

Cattle Breeds explained (american-centric)

btw, the fourth breed is Angus. So at calving time this year I saw crosses in all varieties and colours of Holstein-Friesian, Jersey, Brown Swiss and Angus.

My calves scattered themselves into four different paddocks last night (grr - dog, dim light, appeared suddenly) and had to wait till morning to be gathered up and fence and gate fixed (they'd spent the night chewing on tape gates - double grr). Not really thinking, I found myself walking behind a lovely grey animal, and looked at her thinking, "there's some cross-breeding there." She was the wrong colour and shape to be a straight Jersey-Friesian cross, looking just like a Jersey with a bit of something else, and I was wondering who her mother was thinking she'd obviously got the 'extra' from her, since I'd only used pure-bred bulls.
Much later, I got sight of her again in the group and decided I was an idiot.
She's Brown Swiss crossed to a Jersey/Friesian crossbred - the only heifer of the four BSx that were born this year. Since weaning, her coat has altered to the more typical grey colour of the Brown Swiss, to match her head - a birth she was a pinky-beige with a dark face, almost indistinguishable from a Jersey.
She's a magnificent animal. I hope to see a few more like her next year.
(Note, at weaning I expect her to make the same weight as a crossbred - even though she looks like a Jersey, her mature weight is significantly greater and weaning her at the same weight as the Jerseys is too light. This year I'm weaning Jerseys at 70kg or above, xbreds at 80kg and my one pure Friesian was over 100 kg at weaning - and usually eight to ten weeks old).