Cows at Grass

Isn’t it strange how things go around in cycles? Some years ago there was a tendency on some of the smaller dairy farms to get the cows out to grass as early as possible in the winter so it was not unusual to find cows at grass in late February or early March whatever the weather. Dairies did not seem to be so interested in clean milk then and sometimes it was done to economise on limited stocks of available fodder and to save on bedding straw.

Adequate Access

Things are very much different now that we expect so much more from the cows and it is not acceptable to milk animals that have been lying out in a muddy field all afternoon because try as you will it is not possible to get the teats clean enough for milking during a wet spell. Our winters have changed and it is not unusual to have prolonged mild spells and short cold snaps when the grass will get a chance to grow. If you do not graze sheep over the winter and house the cows in the autumn before there have been too much damage to the pastures you might find that there is significant grass growth by the beginning of March. Often it is the medium and low yielding cows that will benefit most from the winter grass. It only really works if the ground is reasonably dry and you have a network of tracks to get them to the paddocks without causing too much damage to the ground. It is better to keep a close eye on what is going on during the day. If they are lying down or grazing that is fine. As soon as they start to roam around it is better to bring them back in and not risk damage to the ground as it will be slow to recover if conditions turn muddy or cold. It is never a good idea to keep swapping and changing the diet, but it will be inevitable if there is a wet spell that you might need to bring the cows back in again and give the fields a chance to recover.

Problems with Staggers

Early grazing does not suit all of the cows. We have already had problems with staggers on a dairy farm. At this time of the year most of the feed suppliers add extra magnesium to the ration, but there is still a danger that low yielding animals may not get sufficient to meet their daily needs. If you are mixing your own ration it is better to calculate the daily intake for animals that are on the lowest rates as they are the ones that are the most vulnerable to the disease. Cattle have an instinct to find magnesium when their blood levels are low so they will lick at the ground and drink urine if they get the opportunity. This is why the magnesium buckets work so well. Sometimes you might have a job to keep up with their initial requirements, but once they have satisfied their needs intake will level off and they will only occasionally lick at the mineral. The buckets are most useful for suckler cows with a variable feed intake and as an insurance policy to make sure milking cows have every opportunity to find the mineral.

Poor Weather

Staggers can sometimes be triggered by a period of rough weather and it might be possible to house the animals at the most vulnerable times. Some individuals seem to be particularly susceptible to staggers what ever you do. It might be that they do not eat enough concentrate even though it is offered or they will not take magnesium from the buckets. I like to use the Rumbul Rumen Bullets on any cows that have survived staggers in the past particularly if the rest of the herd have sufficient supplements. These slowly release magnesium into the rumen whatever the feeding activities of the cow.

Laboratory Opening House

We have had a message from the Veterinary Laboratories Agency in Shrewsbury to inform us that they are restricting their opening hours from 8.30am to 10.30am on Saturdays. This does not give very much time to get organized if you have any animals that need a post mortem at the week ends as a delay of 48hrs may make it difficult to get a comprehensive diagnosis.

Shortage of Copper

You will be familiar with swayback and the way that a shortage of copper in the second part of pregnancy can affect the development of the spinal chord of lambs. It is lambs born on hill farms that are the most likely to show symptoms of swayback. Affected animals loose control of their back legs and tend to move with an uncertain gait. There is no effective treatments once symptoms are seen although mildly affected lambs with often fatten provided they are kept on smaller fields and are given generous amounts of creep feed.

Copper Toxicity Vulnerable Animals

The other, in some ways more serious problem, which we have with copper, is over supplementation. Where there is too much copper in the ration the liver tries to mop up the excess and can become irreversibly damaged. Affected animals will look full and will often continue to feed. If you take a closer look the membranes of the eye will seem to be pale and tinged with yellow. Animals that we see with copper poisoning tend to be Texels, Blue Faced Leicesters or Charollais. Ram lambs are the most vulnerable if they have been kept in all winter and have prolonged periods of concentrate feeding. There is no effective treatment for copper poisoning in sheep. You may be able to identify the early symptoms comparing the colour of the membranes of the eye of susceptible indivuals with some of the ewes. Blood samples can be used to confirm your suspicions at an early stage withdrawing the concentrate ration may help to avert complete liver failure. Poisoned animals will not grow to their full potential and may be affected for the rest of their lives.

Itchy Sheep

The end of the winter is the time that sheep scab mites and sucking lice are at their most active. When the ewes are closely housed for feeding and lambing there are more opportunities for parasites to spread and for the ewes to rub.

Scab rapidly spreads at this time of the year. Affected animals will stand for long periods by any firm surface and rub until they have large areas of exposed skin. There is an acute inflammatory reaction to the mites that live in the skin and there will be crusty lesions on the edges of areas where the wool has been lost. Some animals seem to spend their entire time rubbing and will rapidly loose weight as they stop feeding.

Sheep with lice tend to do less damage to themselves as the parasite lives in the wool rather than on the skin. The will not normally rub enough to cause significant wool loss and sometimes only a small percentage of the flock will be affected.It is important to distinguish these two conditions. Take wool samples from the edge of the lesions. Sometimes if there is only a low grade louse infection the rubbing will subside anyway as the weather warms up so you might not need to do any specific treatments.