As most of you will be aware TB testing has been keeping us busy over the last few months, but we have almost completed the radial testing around the breakdown herd. We were asked to test all cattle over 6 weeks old on 110 different holdings, some of which gained an exemption from testing as cattle did not graze the land within the 3 km zone from the breakdown. We have nevertheless tested 10 624 animals so far. There are 2 farms left to test of about 420 animals and these will be done in the first week of February (one being a client of a neighbouring practice). We have found 1 reactor animal that has been slaughtered and the farm has been placed on movement restrictions whilst awaiting further results. There have been no inconclusive reactors found so no animals to re test. We have now started pre-movement testing of cattle intended for sale—this is required for all animals over 6 weeks of age moving off a TB1 holding unless they are going direct to slaughter. Please try and give us a couple of weeks notice to get these done, especially as we are now approaching the busy spring season. The test is valid for 60 days from the 1st day of the test.
As lambing time approaches have you given any thought to the successes and failures of last year? Antibiotic usage continues to be one of the predominant issues facing farmers, with an emphasis being placed in reducing prophylactic use. This is determined as using antibiotics in case a problem develops, such as using ‘Spectam’ or ‘Orojet’ to prevent watery mouth in newborn lambs. Over the past few years, it has been increasingly common for all lambs to be given a dose at birth whether there has been a problem on the farm or not.
Last year we had a number of farmers who were much more selective in which lambs were dosed with no increase in disease levels being seen. They decided not to treat lambs born in the first couple of weeks when pens were still clean and had not had a large throughput, and also not to treat single lambs or twin lambs where the mother had a good supply of colostrum.
As you will have heard before the most important thing in rearing lambs is ensuring that they all receive an adequate supply of colostrum—50mls per kg bodywt in one feed as soon as possible after birth and then 200mls per kg in the first 24 hours. It is that first feed that is vital, it encourages the development of the lamb’s own immune system. If it doesn’t get enough in that first feed then it doesn’t matter how much you give it later it will not absorb any more antibodies and so its immune system will not be fully developed leaving it more susceptible to watery mouth and joint ill.
You may notice the national #colostrumisgold campaign running in some of the papers where you will find more information.
As well as lambs, colostrum is essential for newborn calves—they should be getting 6 pints at the first feed, or be seen to suck continuously for 20 minutes. We have a number of farms in the last 12 months where calf health has been poor, especially in the first couple of weeks of life. Blood samples have been tested and have shown poor levels of antibody which means that they have not received enough colostrum. Making a concerted effort to either feed every calf or ensure it has sucked has seen a dramatic improvement in calf health, reducing the need for treating calves with either antibiotics or replacement oral fluids.
Cattle herds will soon be needing booster vaccinations to protect against BVD and leptospira, but unfortunately, there is a problem. BOVIDEC to protect against BVD is no longer being made by Novartis, although we have been informed that another company, Benchmark, hope to start production so we will have to wait and see if that happens. The alternative is BOVELA, a single dose injection which protects against both type 1 and 2, and should be done at least 3 weeks before service to protect the unborn calf.
Leptospira vaccine is currently unavailable due to a global shortage of one of the components of the vaccine. We have no date as to when the vaccine will become available again but will let you know when we find out.
We do however have HUSKVAC available to protect your replacement heifers against lungworm. Calves need to be 8 weeks old when they receive the first dose, with a second dose being given 4 weeks later. They can then be turned out 2 weeks after that.