Source: Alberta Agriculture and Forestry
The third article in this six part series looks at benchmarks and ways to track the genetic performance of the herd.
A pilot project aimed to help Alberta producers adopt new technology and innovation recently brought ranchers and farmers together with experts and scientists during a tour of east-central Alberta farms. The group discussed cattle record keeping and herd averages.
A case study used Rancher X. He wanted a better way to track the genetic performance of his cattle retained for slaughter. Implementing DNA sire parentage was a way to group the weaned calves into sire groups to assess carcass quality and carcass value later.
However, there was no complete record keeping system for his herd, so that meant the first step was to track herd benchmarks.
“Individual cow records are important when specific changes to genetics and management are sought,” explained Susan Markus, livestock research scientist with Alberta Agriculture and Forestry. “But, in other cases, herd averages might flag issues or opportunities for improvement.”
When it comes to cattle record keeping and herd averages:
- Researchers found that some producers feel that because they feed, manage and market in groups, an average is a good measure to track cattle performance.
- They also say that group averages are likely what is needed for many feeding groups and management systems. However, producers may have difficulty improving difficult to measure traits like carcass quality and feed efficiency with genetics if an average is the only information recorded.
Markus said that averages are only good for the intended situation. “For example, an average weaning weight of 640 pounds for 8 month old calves might sound impressive, but you need to dig further. If this same ranch had weaned only a 78% calf crop, that weaning weight is best measured as the average weaning weight of calves from all cows exposed to breeding.”
“If the number of cows exposed to breeding was 400 and there were 312 calves weighing on average 640 lbs., the newly calculated weaning weight – taking open or cows whose calves died into account – now works out to 499 lbs. It is not so impressive from a whole herd perspective.”
“This average means aspects like breeding season length, fertility, death loss and nutrition are areas that can be investigated to make improvements in productivity. If calves are dying, the reason why will be important to know in order to make improvements to a below average weaned calf crop percentage.”
Markus added that the second step is to evaluate GOLD indicators – herd benchmarks that inform how well cattle perform against industry standards, defined as:
G – Growth in kg or lbs. – average weaning weight of calf per cow exposed to breeding, or total weaning weight of all calves weaned divided by total number of females exposed to breeding. Consider grouping the herd into first and second calvers versus mature cows. Average cow size and weight should be known, but be careful to avoid underestimation of cow weights – scale weights are best. Aim for calf weaning weights at less than 9 months of age to be greater than 45% of mature cow weights. If also tracking birth weights, aim for 7% of cow weight to be an acceptable calf birth weight.
O – Open rate – percentage not pregnant, number of females not in calf divided by total number of females exposed to breeding. It is usually determined in the fall after weaning spring born calves. Aim for greater than 95% pregnancy rates.
L – Length of calving season – number of days from birth date of first calf born to date of last calf born. Aim for greater than 65% calves to be born in the first 21 days.
D – Death loss – percentage of animals that died. This is calculated by the number of animals that died divided by the total number of animals in the herd. It can be done separately for calf crop, feeders and cow herd. Aim for death loss of calves from birth to weaning to be less than 4%, weaned calves to marketing less than 2% and mature cows less than 1%.
In the case study, Rancher X knew this information, but did not record it to confirm all the numbers. When the time came to assess the issues, his memory was not as clear about the numbers as he once thought. He was less able to pinpoint causes and implement solutions. Once he knew that the weaned calf crop was lower than anticipated, then marketing the calves, hauling bales, purchasing grain and fixing some fence took priority. The urgency was lost until the next year.
Having someone assess his situation and determine that calf death losses were mostly occurring after birth indicated that fertility and breeding season length were not the issues. Rather, he had a high rate of early death loss from calves less than one month of age. After investigating deficiencies in the cow nutrition program and analyzing scours outbreaks, management changes were made for the next year.
Rancher X has the benchmarks for his ranch on track now and is focusing attention on specific genetic improvements for carcass quality and feed efficiency as he finishes his own calves. Sire averages will provide the level of detail necessary to inform his decisions, rather than relying on herd averages. He is now pursuing individual cow record keeping and tracking parentage. Using tools designed to get the information he needs, in the most efficient way, is how this rancher is approaching herd record keeping.
The group conducting this project included researchers at the Alberta Beef Forage and Grazing Centre (ABFGC) along with specialists at Alberta Agriculture and Forestry, members of the Alberta Beef Producers and the Agricultural Research and Extension Council of Alberta.
Contact
For more information on this series, contact Susan Markus:
Email: susan.markus@gov.ab.ca
