Reproduction

HOW DO WE INCREASE OUR CALVING PERCENTAGE IN OUR NORTHERN BEEF HERD?

This is a regular question we get asked from graziers a lot but the words “without spending any money” normally follows this question. If you spend nothing you normally get nothing but you need to make sure what money you are spending is giving you the best return.

Firstly, you need to identify exactly what your current production is, calving percentage, weaning percentage, bull percentage etc. Then identify what is limiting your production & make a list.

Do you have any physical restraints like bull fertility and percentage? Lack of feed? etc.

Once you have a handle on your situation you can then start to manage your way forward. I believe nutrition is the most limiting factor stopping an increase in calving percentages in northern Australia.

Physical restraints can be better managed once identified but it is our opinion that nutrition is the most limiting factor on reproduction in northern Australia. Nutrition controls the body score condition (BSC) of your cows. Why do graziers in the southern area of Australia get 95 plus percent calving and weaning? And why do some northern graziers regularly wean 20% more calves than their neighbour?

As a survival mechanism, a breeder in poor body condition will not cycle due to self-preservation. It is the way we have bred the cattle in the north. A cow who gets pregnant in poor condition will normally die rearing a calf without proper nutrition. Over time these fertile cows have died in the paddock or been sold due to being in poor condition so we have naturally selected cows that will not get pregnant until they have a BSC of 3 or more.

We believe the average calving percentage in northern Australia is 57%. A cow is pregnant for about 9 months and then the cow will be weaned about 8 to 9 months later. By the time the cow is weaned the cow may have a BSC of 1 to 2. On a mature cow, each BSC is equal to about 60kg of body weight so if she has a BSC of 1.5 she needs to gain 90kg of bodyweight to get back to a BSC of 3. How long will that take your cow to regain 90kg of body weight? Four months at least. So, 9 months pregnant plus 8 rearing the calf and 4 months to rebuild = 21months.
12 months / by 21 months = 57% or one calf every 21 months. If you are under 50% what BCS are your cows?

Below is my guide for what % of cows should be pregnant 60 days or 90 days after calving in BSC 2,3 or 4.

If your cows have a BSC of 3 or more they will start cycling from about 35 days after calving and will continue to cycle about every 21 days until they become pregnant. The average cow will be pregnant for about 285 days leaving about 80 days for the cow to fall pregnant if you want your cow to have a calf every 12 months. That gives you 3 opportunities or 3 cycles for your cow to become pregnant. A cow with a BSC of 1.5 may take 85 days after calving to start cycling.

With heifers, you can start joining at 280kg of bodyweight but they will need extra feed as they still need to grow themselves as well as growing a foetus inside them. They then need to be producing milk after calving. I recommend to get your heifer up to 3.5 BSC for joining. A larger cow should have more body reserves to draw on in the dry. Heifers don’t have the same amount of body reserves and are the first in the herd to slip in condition when the going gets tough.

Heifers should be grazed in your best paddocks and monitored regularly once they have calved. The only thing harder to get pregnant than a heifer is a lactating 1st calf heifer. She is trying to feed a calf and grow herself at the same time. As a survival tool if she is below a BSC of 3 she will normally not cycle to become pregnant.

If the heifer is 280kg when she becomes pregnant she needs to grow to about 400kg as a young cow over the next 2 years while still functioning. Sounds easy so why is it so hard to do? The truth is some graziers are doing this successfully but they consider nutrition and the cows BSC as the most important thing to do with their breeders. To help your heifers you can consider weaning them earlier than your breeder herd to limit any weight losses?

Nutrition is like any tool in your shed or office. You do not need to be an expert at nutrition and understand every detail but your cow’s will respond better when you get it right. Timing the supplements you feed out to your cattle to the exact time of the year or breeding cycle, you can increase weight, minimise weight loss and maximise fertility and profitability. Most graziers are already spending sufficient money on nutrition but by changing the supplement or the timing of the supplement program they could be rewarded with extra calves.

We believe supplementing with our Breeder supplement could improve your calving percentage if supplemented at the right time of the year. Ultralix Breeder supplements are high energy with balanced protein, phosphorus and minerals and will improve the Dietary Cation Anion Difference (DCAD) balance in your cow’s diet. A healthy cow with the correct DCAD balance will be able to better mobilize calcium, phosphorus and nutrients within their body when it is required during the year.

If you are wondering if you could benefit from some extra calves each year, please give us a call.

*Note, calving percentages are one thing but you also need to think about weaning percentage. It’s no good loosing calves once they are born but that is for a later article.