STOCK BULL LEFT STANDING BY AI CALF RESULTS
Synchronised breeding and AI have improved returns
and cut costs for one north Devon suckled calf producer.
Jonathan Riley reports
CALVES sired by top quality AI bulls have achieved sale prices over £20 higher than calves sired by the stock bull at Robin Mays Slattenslade Farm, Parracombe.
This extra margin has been achieved despite the fact that the farms stock bull is rated in the top 5% of Charolais bulls.
At Slattenslade 60-65% of the 40 spring calving, dairy cross sucklers hold to AI service with semen from Charolais Friarton Ensign.
Ensign has a beef value of CH57 placing him in the top 1% of Charolais bulls. The remaining cows are served by Mr Mays Charolais stock bull Heywood Hugutoo which has a beef value CH32.
"AI bred calves grew at 1.34kg/day while stock bull sired steers grew at an average of 1.22kg/day.
"Because we havent got space to finish calves, this extra growth is vital so that calves sold in November reach sale at the highest weight possible," explains Mr May.
"By sale time this autumn, the AI-bred steers had reached 347kg and sold for £448.40 a head. They also had a better conformation and appearance and achieved a slightly higher price/kg than the stock bull reared steers which reached 305kg and sold for £408.70/head," he says.
He believes that if these animals could be finished at Slattenslade, the faster growth rates would create a still greater difference between the steers from the two service regimes. And extra financial gain would be derived from better grading.
In addition to the improved returns, savings in bull keeping costs are made, particularly during winter when labour, feed and bedding costs can be considerable for bulls.
Mr May also points out that cost savings are made because he can choose a bull conferring easy calving. This minimises calving problems which reduces calf mortality and means the cow returns to oestrus more quickly, improving herd fertility and hence boosting production. Costs too are reduced because there is no need to assist cows during calving.
Mr May also uses Crestar implants to synchronise cows. These are implanted into the ear by a vet and removed nine days later. At the time of removal a hormone injection is given to stimulate ovulation before AI 48 hours later for heifers and 56 hours later for cows.
These cows calve within a 17-day period which means more of the progeny have a longer growing period before sale in November.
"Knowing when cows will calve also aids planning of feeding and condition management which in turn improves fertility," he says.
"From the AI date we also calculate a date to turn cows out a week before calving. This we do on Mar 1 so that newborn calves are not exposed to bugs which have built up in the shed during winter."
Robin May uses a Crestar implant in the ear to synchronise his cows.
• Use of superior genetics.
• More uniform stock.
• Faster growth rates.
AI is enabling suckler producer Robin May to use superior genetics and breed progeny which grow faster and have better carcass conformation.