Yup. It’s that time of the year. The time to get all of our lovely cows back in calf so that they can carry on being productive members of the herd for another lactation after they finish this one. Some of you may not understand why we have to breed our cows…I worked with a milker once, who despite having worked in the industry for TEN YEARS , didn’t know that cows had to give birth before they could start lactating….I found this rather worrying and asked him whether he knew any women who started leaking milk everywhere without having a baby first? That seemed to clear up his confusion, but at the time I thought to myself ‘if a guy who’s been milking cows for 10 years doesn’t know this, what about the average layperson’?
So basically here is how it works: we try to get our heifers (young females who haven’t had a calf yet) in calf when they are about 15 months old. That may seem a tad young to many of you, but young females can reach sexual maturity as young as 4-6 months, and you really don’t want a bull rampaging about the place at that point. There is such a thing as too young and too small. So the aim is to have them coming into the dairy when they hit about 2 years old. Getting the nutrition right for these little ladies is absolutely crucial as they are still growing throughout their pregnancy as well as growing their calf – so they need a high energy and high protein diet to ensure they get the size they need before they give birth. We aim to have them at about 85% of the bodyweight of a mature cow, ie a cow who has finished growing (we generally look at 3rd lactation cows for this figure). Depending on the breed and general size of your cows, that varies enormously, but our mature cows weigh about 650kg, so we want our heifers to come in at about 550 kg….with me so far? The reason we want them at this size is the same reason we don’t want any bulls getting in with our young stock – calving ease. Ideally, you want your heifers, and cows, to calve on their own, without any assistance as the more interference from us, the higher the chance of post calving infections and infertility as well as the stress it causes the animal which interferes with how well they milk.
Next, once they have had their calf we give them what is known in the industry as a ‘voluntary waiting period’ which is a period of time between when they calve and when they get pregnant again. Dairy farmers are often accused of keeping cows pregnant all the time, and how cruel it is…let’s just say that in a herd of wild animals, the females are impregnated as soon as they reach sexual maturity and male animals certainly don’t give cycling females a break just because they’ve recently given birth…so we are actually pretty civilized by comparison!
Anyhoo, there are two ways we can get our cows pregnant: by running bulls with the herd, or by artificial insemination (AI for short) or, in many cases, a combination of the two. Most farmers, and that very definitely includes moi, prefer AI to bulls. Bulls have a certain…shall we say reputation. They are big, heavy, noisy (they don’t moo nicely like a cow….they roar) and potentially dangerous animals. And not just to us. I’ve seen a bull jump a 7 foot tall steel rail in a yard, get stuck half way over and then bounce on the rail until is was bent low enough to climb over…I’ve seen another big boy tip a slightly smaller bull (only weighing about 1000kg) backwards over a fence with a flick of his head because he was feeling irritable….Not only are bulls destructive and dangerous, they can injure the smaller cows, or even the bigger cows if they don’t have secure footing. They can also spread STI’s. And the obvious OH&S problems they raise for staff working with them cannot be stated loudly enough. Having said that, they can pick a cow that’s on heat waaaay better than we can. So they do have some advantages.
So, on to AI. With AI we can select bulls from anywhere in the world. We have charts which in Australia we called ABV’s (Australian Breeding Values) which can tell us a whole host of information about what traits that bull can bring to our herd: milk production levels, stature, udder strength, teat placement, foot and leg conformation… the list goes on. Every country has it’s own version of our ABV’s – it’s just a matter of learning to decipher what it all means. So basically we have a huge advantage: we can select 30 different bulls to perfectly suit all of our individual cows in the herd if we so choose without having to have a single bull on farm. Also, all the bulls that go into AI are screened for diseases – another massive advantage. The only downside. especially if you live a long way from anywhere, is that to perform AI, you need a trained technician. Anyone can go and get the training they need to become and AI tech, but not everyone will become a good or even competent technician. You need loads of practice for a start, and who wants you practicing on their cows when a missed heat can cost the farmer up to $140 per cow? You also need a lot of patience, a good eye for heat detection (which involves understanding cow behaviours and physiology) and be willing to potentially stand around for hour upon hour watching cows go by on a carousel. Which is where I come in.
My view for the next 2 months
For us, right now, it’s AI season. For the next 2 months I will not have a day off. I will spend an average 5 hours per night standing on a hard platform watching cows bums go past on the off chance I’ll see a cow cycling. I dream of cows at night. But I’m not complaining. I’m making the cows more comfortable and safe not having bulls in the herd. I’m bringing new, young blood into our herd for the next generation of milking cows so that they may live longer and more comfortable lives. I’m choosing to give freshly calved cows a rest before they have to do it all again. I’m in control and I’m loving it. We’ll still run bulls later in the season. But I will have done the vast majority of their job for them. Bulls who are less excited do less damage – to everything and everyone, except maybe each other (like most males they like to scuffle and puff their chests out to see who the bigger man is). So all in all, it’s a good time of year. Certainly the weather could be nicer, but that’s just how it is right now.
T’is the season.
dairylove 