VET’S COLUMN: Good pregnancy rates for cows

Autumn is here at last and my workload has increased with routine pregnancy diagnosis for the spring calving suckler herds and testing for Johnes disease a major part of that.

The cows are generally in good condition and pregnancy rates reflect this. The best so far being only three cows not in calf out of 106 that were bulled for only six weeks. Short bulling periods suit the management of some farms and, if everything works well, can give results as good as a more normal 12-week bulling period.

The six-week bulling can fail spectacularly if something goes wrong and the bull fails to perform for some reason so it’s vital to do pre-breeding checks with this system and also keep a very strict eye on progress.

Routine Johnes testing of herds has, in some cases, apparently eliminated the disease, but on most farms it has just reduced the incidence to very manageable levels.

The emergency calls to calvings, milk fevers and staggers are fitted in around the routine. We have done more caesareans this autumn as cows are fit and the calves have grown well before birth. 

Staggers, or hypomagnesaemia, has caused serious problems on some farms, with cows often dying before any treatment could be given. Last week, I was fortunate to treat a cow that was just showing nervous signs. When I checked her blood magnesium levels they were virtually zero so it was surprising she was still alive. Prevention with a daily feed containing magnesium, plus access to straw to slow passage of food through the gut, is definitely better than trying to treat affected animals.

Sheep are also taking up a fair amount of the time, whether it’s giving advice on vaccines and wormers, checking ewes’ mineral status prior to tupping, or making sure the rams are fertile before they go to work. We test a large number for fertility and often treat them with micotilto control lameness prior to use.

Housing of cattle is approaching rapidly and a plan to prevent pneumonia should be in place. Lung worm infections have been exacerbating pneumonia outbreaks so treatment prior to housing is advised. Vaccinating and worming prior to housing, plus weaning three weeks after housing is the safest policy, but not always possible. A careful watch on housed calves is needed especially as the weather now seems to have changed to soft and wet.