Dairy farmers calving in the spring should identify cows that are at risk of not cycling and take steps to help get these cows back in calf with the rest of the herd, attendees at a farm walk in Co Down were told last week.

Speaking at an event organised by AI Services on John and Jason Rankin’s farm near Newtownards, New Zealand vet and fertility specialist Joyce Voogt described getting cows in calf as a race against time.

She pointed out that there are 12 weeks from calving to conception if a cow is to calve down on the same day the following year. “If there is a six-week compulsory stand-down period after calving that means there are only six weeks or two cycles to get her in calf,” Voogt said.

Her advice to farmers was to check heats before breeding so that cows that have not cycled can be examined by a vet and an early decision can be made on the need for treatment or synchronisation.

Cows at risk of not cycling include those that had difficult calvings, retained cleanings, a recent health issue such as lameness or mastitis, or have low body condition. Late calvers are particularly at risk in block calving herds of not cycling in time to get served. “It is important that late calvers are healthy, not overfat and have a trouble-free calving,” Voogt said.

The period between calving and breeding is a critical time for uterine health, which affects the strength of heats and egg viability.

However, with the start of the grazing season delayed in NI this spring, farmers were warned that concentrate feeding should only be reduced gradually once cows go from silage to grass-based diets.

Embryo loss

According to Sam Campbell from AI Services, the poor spring means loss of embryos or reabsorptions could be an issue on many farms this year. He said that concentrates need to have a high proportion of undegradable protein, such as soya bean.

“There are degradable proteins in grass and compounders can include it to increase crude protein levels.

‘‘Undegradable protein is what you need,” Campbell maintained.