Extended AB a ‘good option’ for some
More Southland dairy farmers are expected to extend their artificial breeding (AB) programme this spring as they aim to reduce their biosecurity risk.
Diseases such as Mycoplasma bovis has heightened awareness among farmers, some of whom are increasing their AB programme from the traditional six weeks up to 12 weeks.
DairyNZ consulting officer Leo Pekar said an extended AB programme reduced the risk of introducing diseases into the herd as less or no bulls were required.
However, it would require a lot of discipline on the part of farmers and their staff, he said.
‘’Farmers will need to adopt a system that will cope with an extended AB season.
‘’Mating is one of the most intensive times on a dairy farm so you need to have a good plan in place to monitor cows on heat,’’ Pekar said.
The dairy breeding season starts in late October or early November and runs through until late January.
‘’Extending your AB period means you can easily lose focus at a critical time during mating.
‘’You need to have enough silled staff on so that people don’t get fatigued and you can employ a relief milker if needed.’’
Other benefits of an extended AB programme included having more heifer replacements to select from as well as extra income from surplus heifers and higher value calves.
AB mating all the herd would allow for better planning during next year’s calving as all matings would be recorded.
However, there were pitfalls to an extended AB programme such as missing cows that had silent or quiet heats and fewer cows cycling as more get in-calf which would make heat detection more challenging. It also meant an increased workload over the Christmas and New Year period.
The easy option was to put the bull out with the cows after six weeks, which was usually in midDecember, to catch the late cycling cows, Pekar said.
‘’The bull is the safety net. ‘’The cows that are hard for us to find the bull will find.’’
Pekar urged those farmers that stick wiith a six-week AB programme to select their bulls carefully.
‘’It’s important to do your homework – know where the bulls have come from, their history, as well as the biosecurity practices on the source farm.
‘’Ideally you want to be buying bulls from a stud breeder.’’
Pekar said farmers should source well-grown yearling virgin bulls from a closed herd as they carried the least disease risk.
He also suggested pre-booking next year’s bulls if they were happy with their stud breeder.
‘’But you still need to have that conversation around biosecurity.’’
Pekar said bulls should also be quarantined on arrival for at least seven days and ideally two to four weeks before putting with cows or heifers to check for signs of illhealth.
He encouraged farmers to start monitoring their herd 24 days before the planned start of mating and get any non-cycling cows vetchecked.
‘’You want to see about 85 per cent of cows cycling before mating and if it’s lower than 75 per cent you should get advice.’’
Costs add up
Poor heat detection could cost farmers more than $200 per cow in lost milk production, according to DairyNZ consulting officer Leo Pekar.
Pekar said farmers who missed picking up cows for mating on their first cycle could lose around 1.6kg of milk solids a day over 21 days which at $6.50kg/MS would cost farmers more than $200 per cow.
‘’It adds up very quickly. ‘’Every time you miss a heat you’re losing three weeks of milk production and the cow is less likely to get back in-calf,’’ Pekar said.
This would also have a flow-on effect with late calving cows costing more to winter.