John Alexander is a vet with Ark Vets in Lockerbie where 80% of his workload revolves around dairy cattle. He covers a wide area throughout the North England and the South of Scotland from Selkirk to Longtown, Abington to Dumfries. The SF caught up with him to get his intel on the potential health risks to dairy cattle.

What are the most common ailments in dairy herds at present?

“Last year a lot of people made problematic forages, particularly later cut silages that were maybe cut when it was wet. We are seeing issues in cows in what I suspect is mainly acidosis or mycotoxins. We were seeing quite a lot of loose dung and also animals exhibiting fertility issues as well such as cows not getting in calve as quickly as you would expect them to.”

Do you have any advice regarding preventing the above? Is it mostly down to the poor forage?

“I suppose, there’s not a lot you can do if you have to feed them what you have. If you can, feed the poorer forage to your youngstock as they aren’t under as much pressure as your milking cows. Also try and manage other stressors as much as you can. If you can balance the forages out better, for example if you have made a few cuts of silage, you can take feed from other pits or feed with an alternative source like maize silage. It depends what’s available for different systems and on farm, but buffer forages as much as you can with different sources of forage. Regarding other stressors, try and make sure cows aren’t too tightly stocked, and make sure other infectious diseases such as IBR, BVD, salmonella are managed by vaccinating.”

Any advice on Q Fever?

“Q Fever is a funny one. How clinically important Q Fever is we still don’t really know. It is more common in sheep and goats, but I haven’t personally seen it in cattle. I have never identified it in abortions, or as a definite cause of infertility. The symptoms for it are generally quite vague in cows, it causes an increase in abortion, infertility, stillbirth, weak born calves. There are multiple causes for that which don’t necessarily link to Q Fever.

Infertility is such a multi-factorial thing, and the causes of it can vary – nutrition would be well up on my list of causes ahead of Q Fever alongside infectious diseases such as BVD, IBR, Leptospirosis. So Q Fever, I honestly wouldn’t be pinning too much on it at this point in time. I think there will be more work done on it in the future and there is a commercially available vaccine for it but we are not seeing a lot of issues with it in cows up here.”

Advice on laminitis and lameness?

“Lameness is a major issue in cattle but laminitis is a specific condition that is a bit niche for dairy cattle. You are mainly seeing sore ulcers, sore bruising, digital dermatitis, and white line disease in dairy cows and that’s all to do with the amount of time they spend on their feet and walking about.

Causes of lameness are either infectious or mechanical and the most common issue is digital dermatitis. It’s prevented mainly through regular foot bathing with copper sulphate or 3% formalin and also managing slurry. A regular milking herd should be foot bathed at least four or five times a week but everyday if possible. All stock need to be done on the farm to include youngstock and dry cows even if is only once a week. Another measure is reducing standing time for cows, especially when they are waiting to be milked. Also make areas where they do stand more comfortable – some farms have put rubber down so cows are standing on a more shock absorbent surface.

We also recommend farmers get their cows’ feet trimmed routinely at around 70 to 80 days in milk and do a pre-dry off trim as well. Hoof trimmers should be in at an absolute minimum once a month and with bigger herds they should be in every week or every two weeks.

The other thing about lameness I recommend is getting cows’ mobility scored and then get the lame cows’ feet lifted as quickly as possible so that the score twos don’t end up as score threes.”

How would you prevent scour?

“With scour it is always important to identify whether it is infectious or nutritional. We have seen a lot of scour early this year due to the poor quality silages. If it is nutritional it can be resolved by including more dietary fibre like straw in the herd diet. Others ways to solve it include a mycotoxin binder because I think there might have been some heavily mycotoxin contaminated silages this year.

When it comes to infectious causes, Johnes is obviously a big one but everyone should be testing for the disease and dealing with the recurring infected cows as they are perpetuating the problem. In south-west Scotland we see a lot of Salmonella and people should be vaccinating but it is one to always be aware of.

BVD is pretty well controlled through the vaccination schemes which means we probably don’t see as much of it anymore.

In grazing dairy herds, worms are still a possibility and will cause milk drop and potentially scour in cows.

In youngstock, scour tends to be caused by worms and Coccidiosis, with the latter usually sticking it’s head up in most dairy units between four weeks and two months in line with a stressful period. For example we see it a lot during weaning time or sometimes during a busy calving period. At an even younger age we see a lot of Cryptosporidium and Rotavirus although they are nothing new – they are always kicking about. There are various vaccines for Rotavirus you can give cows which gives the calves protection through their mothers’ colostrum. Ultimately with young calves it is about getting them a good quantity of quality colostrum as quickly as possible ideally in the first six hours of life, as well keeping calving pens as clean as possible. Try and use disinfectants that are known to kill Coccidian and Cryptosporidia or use steam cleaners between batches of calves.”

What are your thoughts on transition cow management?

“You have got to feed dry cows right and feed fresh cows right. Make sure dry cows aren’t getting too fat and are being fed an appropriate diet. They need to be fed the right amount of energy and dietary fibre and both need good intakes. If you run into an issue, you could end up with fertility problems for the next 90 days.

The eggs that are ovulating by the time you want to serve a cow are developing within the ovary three months prior to that so it is crucial to get your transition cow nutrition right. In terms of future milk yields, if a cow doesn’t transition well she will adjust her yield down to survive and she will never really recover from that. So a cow that could be giving 50 litres could go through a bad transition allowing her to give only 30 and she will not be able to increase that amount no matter how much you try and feed her.

In terms of managing transition cows, speak to your nutritionist to make sure you are feeding the cows what they need. You don’t want them too fat before calving but you want them to get the energy they require so they don’t go into survival mode. You want their condition score to sit at about 3 and once they calve you don’t want their condition score to go down more than half a point so 2.5.”

What is the one thing dairy farmers could be doing to improve their herd health?

“What you get out of cows is what you put into them. Just make sure you are feeding them right. Nutrition is the key to everything. It’s the key to fertility, it’s the key to health. By making good quality forages and adjusting appropriately, you can mitigate poorer quality forages by buffering them out with other forages, or compensating with other components of the diet, or buying in forage from elsewhere.”