Good mineral status key for trouble-free calving season
The three key checkpoints for nutrition of dry cows in late pregnancy are body condition score (BCS), forage intake and mineral status. This is according to the latest advice from Teagasc, who in conjunction with Animal Health Ireland and Volac, is holding a series of calf-rearing farm walks this month across Ireland.
It advices optimum BCS at calving is 3.25 with a range to 3.0 to maximum 3.5. Meeting this target reduces the risk of milk fever and other health disorders, and promotes better fertility.
“Where silage is good (70dmd plus), later calving cows may need to be feed restricted during January and February to avoid over-conditioning.
“Ensure that cows are offered ad lib access to clean forage and adequate water during the final two to three weeks before calving.”
According to Teagasc, it is too late to fix BCD problems at that stage, so focus instead on achieving stable intakes.
“There is no benefit to introducing meal for one to two weeks pre-calving where silage quality is good.”
In addition, Teagasc advisors are saying proper mineral status is important for a trouble-free calving season.
“Trace minerals (copper, selenium, iodine, zinc and so on) are required in tiny quantities and can be delivered as boluses or fed directly. On the other hand, essential major minerals like magnesium and phosphorus ‘P’ are not covered by trade boluses so these should be offered directly.”
The agriculture advisors also say to provide at least 20g of supplementary magnesium per day to help prevent metabolic problems at calving.
“High potassium (K) content in silage is a risk factor for milk fever and retained placenta. Leafy first cut silage tend to be higher in K. Where such problems exist, switch to feeding second cut or haulage material for two weeks per-calving and increase magnesium feeding rates.”
Four calf-rearing farm walks are taking place in January, in Cork, Limerick, Offaly and Meath. All farm walks will address colostrum management, feeding for growth, managing the scouring calf, calf housing and Johne’s disease.