Planning and Sampling: The Key to Healthy Stock This Winter
Chris Gregory MRCVS discusses…
There is no shortage of helpful advice when it comes to stock management and housing through winter, though in reality every holding is likely to have a slightly different approach. This article summarises some of the considerations from a Veterinary perspective.
Housing vs. Out-wintering:
The decision to house or out-winter will always be farm dependent based on factors like building availability, grazing strategy, calving pattern, stock type, pasture suitability, prevailing weather and often a bit of trial and error! Clearly there is no template approach but both have their advantages and disadvantages with regards to practically and cattle health.
Having a solid feeding strategy for winter is essential to ease transition onto majority conserved forage. Knowing the quality of your forage via analysis is useful in determining the level of supplementary feed required and hence budgeting bought in feed against home produced feed.
Feed space can often be limiting, especially if feeding restricted quantities. The standard advice is that all cattle should be able to feed at the same time. Suggested trough space allowances are 50cm/head for store cattle, 75cm/head for sucklers.
Water. It is the most important nutrient and cattle can drink up to 5-7 litres of water per kg dry matter consumed, often drinking together after feeding. Drinkers should be able to cope with peak demand. Continuous access, fresh, clean water is essential so troughs should be inspected daily and cleaned out if contaminated with straw/dung.
The major diseases associated with the winter period can be roughly broken down into three categories: parasites, pneumonias and scours.
Parasites: Winter can be an opportunity to break the cycle of infection with internal parasites accumulated over the grazing season. Worm and Fluke lifecycles become interrupted during the winter allowing the varied arsenal of wormers and flukicides to clear burdens before the following spring grazing season. The timing and choice of product(s) will depend on when/if cattle are housed, grazing strategy and experience.
Likewise when cattle come in to prolonged close quarters the external parasites also become more common. Mite and lice infestations often occur up at housing. Itching, hair loss and skin reactions are the common signs. Problems can range from mild to extreme, but will always have some form of production impact (e.g. reduced feed intakes, decreased lying times, irritability). Early intervention is key as the infestations can be rapidly contagious.
In all cases it is essential that the correct products are used at the correct time, not just to ensure maximum effect but also to reduce the chance of resistance to the product on farm. This is usually an area where a well thought out health plan or a discussion with the vet/SQP can be very valuable.
Pneumonia: Whether you’re bovine or human, cold winter winds and predictably wet weather are the perfect conditions to challenge the immune system. There are too many factors contributing to the causes of pneumonia to cover in one paragraph, but there are three aspects that help illustrate the issues.
- The animal – Develops it’s own immunity. Initially based on good quality & quantity of colostrum, then over time relies on either natural exposure (and hopefully recovery!) to disease or controlled exposure via vaccination. Good nutritional status is also very important.
- The environment – Is the central factor. Ventilation, hygiene, humidity, stocking density and biosecurity all need to be controlled to reduce the accumulation and spread of pathogens and respiratory irritants.
- The bugs present – Can be farm-dependent, but knowing what bugs are around gives an idea of what control measures/vaccinations are most likely to work. Some routine blood sampling can establish who has been exposed to what.
Preventing pneumonia therefore relies on knowing what bugs you are dealing with, then manipulating your environment to make it as antisocial as possible for the bugs you do have. Finally you may have to consider additional protection in the form of various vaccination strategies. The key message is that all three factors need to be addressed equally. Relying on vaccination alone is not enough; I often use the analogy of a dam wall holding the water back. The vaccine will build a dam wall so high, but if the challenge is too extreme the wall is overcome.
Scours: There are multiple causes of scours from nutritional to parasitic, viral and bacterial. The emphasis on prevention relates similarly to the above advice on pneumonia. As with pneumonia, the knock-on effects of clinical cases can be devastating to growth rates and productivity.
Regardless of the cause of the scours re-hydration therapy will play the central role in nursing protocols. There are a multitude of rehydration products available, some very good, some equivocal, some useless. My advice would be to work out a protocol with your vet that anyone on the farm can follow easily. Additional medicines can then be added to the basic protocol as required per-diagnosis.
As with pneumonia it is important to know what bugs you are dealing with, both in terms of current treatment protocols but also for future reference. Getting a diagnosis from some group dung samples can help target preventative treatments, especially where problems with ‘cocci’ and ‘crypto’ are encountered.
In summary the key message of this article is that some simple health planning and sampling can hopefully go a long way in preventing some of the major winter health problems.