THE TWO-DAY TOTAL DAIRY SEMINAR in Gloucestershire, formerly the Large Herd Conference, attracts veterinary surgeons, farmers and a broad swathe of the dairy industry.
Four parallel sessions operate throughout with speakers from the 14 lectures also leading workshop sessions. The
programme offers delegates presentations within workshops or a more formal lecture setting. There is a strong international flavour with speakers from America, Australia, Spain and the UK.
Zinpro and Zoetis are platinum sponsors with an impressive list of “gold and silver” supporting sponsors. A comprehensive exhibition accompanies the seminar. The quality of support is high and the exhibitors recognise that the emphasis is on dairying with relevant support staff and displays. Some of the conversations were clearly progressing over more than one visit to a stand.
Professor Ian Lean (University of Sydney), managing director of research-based consultancy Scibus, has a particular interest in the factors influencing farm pro t from a biological and economic perspective and he addressed the incidence and technical details of sub-acute ruminal acidosis.
His opening point for clinicians is to “reject pH as a definition of acidosis” as it is far too simplistic. In individual cattle pH is a poor predictor of acidosis, considered to be an accumulation of organic acids that reduces microbial protein yield and fibre digestion. Acidosis is of concern, with trials indicating that around 10% of all cows are sub-clinically acidotic on a single day in Australia and Ireland with more in the US.
Herds with a high incidence have been shown to have an increased number of lame cows. There are challenges to the historical understanding of the effects of acidosis and past definitions need to be reviewed with consideration of current feeding programmes.
Rapid changes in feed type are to be avoided. Studies have shown the condition is not just a problem of feeding grains, with lush pastures, clovers, wheat and corn silage all considered as risk factors. The bacteria involved need to be de ned but there is a possible role for Streptococcus bovis.
Total mixed rations of protein meals can reduce the herd risk. As with all conditions related to the food of dairy cows, an awareness of the actual consumption and the correct formulation of the ration, rather than the intended feed and volume, is a major consideration when investigating clinical cases.
Professor Temple Grandin (Colorado State University) has developed handling facilities for cattle that are utilised worldwide. Her books include Thinking in Pictures, Livestock Handling and Transport, Animals in Translation, Improving Animal Welfare, Reducing Stress During Handling and The Autistic Brain.
Addressing the importance of good stockmanship, Professor Grandin emphasised that “fear is a proper scientific word” and that stress equals fear. The best stockman has been shown to be the con dent introvert, not necessarily the easiest person to work with or manage but who relates to the stock and provides the right atmosphere for the animals.
Excitable cattle have been shown from many studies to have lower weight gains. Heifers will not forget a bad experience and trying to force young animals by shouting and waving sticks is a bad idea. Breeding for temperament has resulted in easier-to handle cattle. With cows and calves it is important to avoid reductions in mothering and foraging ability.
Cattle that are handled in a low-stress way return to feeding more quickly, but it is important not to handle feedyard cattle during the period that is their preferred mealtime.
Recognised stressors are fear during handling, separation anxiety at weaning, pain from surgical procedures and physical stress from heat, cold and fatigue. The signs of fear and anxiety are tail-swishing (the speed increases as fear increases), head- up posture indicating vigilance and looking around, sweating when there has been little exertion, ears pointing towards things that concern the animal (ear radar) with the ears pinned back when scared or acting aggressively, skin quivering and showing the whites of the eyes.
Keep things simple
The speaker emphasised that on the farm it pays to keep things simple. Animals think in pictures and their fears are very specific. The example of a horse reacting badly to a black hat but calmly to a white hat indicates a bad past experience with someone in a black hat. A blue umbrella is not the same as a blue tarpaulin. New things are attractive when an animal is allowed to voluntarily approach and scary when they are suddenly introduced.
Cows need to become used to different people and the advice is not to vary the time of feeding. Overwork and understaffing leads to people being too tired to bother with stockmanship.
Professor Grandin strongly emphasised that “stockmanship and management matters – it is really, really important”. In consideration of the transparency of cattle handling at abattoirs, with the availability of video phones, she advises “do a good job and do things that you can defend”.
Professor Pamela Ruegg (University of Wisconsin) presented an overview of environmental opportunistic mastitis pathogens with emphasis on the need to recognise the dynamic changes in the nature of mastitis on modern dairy farms.
A simple way of defining the types of mastitis is to consider the exposure from infected milk or exposure from moisture, mud and manure. Two take-home points are that the prevention of subclinical mastitis reduces the number of clinical cases and that the prevention of the first clinical case for a cow is very important.
The bulk tank milk cell count can be very misleading and the incidence of clinical mastitis must be monitored. Different bacteria infect different parts of the udder, have different reservoirs, require different treatments and have different rates of spontaneous cure.
The farmer is encouraged to adopt practices that reduce the new infection rate. As herd size increases, more mastitis cases are likely to be caused by opportunistic organisms comprising many diverse strains.
The speaker emphasised that mastitis remains the most frequent and costly disease of dairy cows, but that solving mastitis problems is technically easy: keep bacteria away from the teats, find the infected cows (treat them or eat them), determine why they get infected, from other cows or the environment and decide how to stop new infections. The management changes that need to occur will be indicated following this approach.
Dr Chris Hudson (University of Nottingham) appeared slightly disappointed that cattle fertility has not been shown to have a similar economic impact as mastitis. However, the decreases in milk production from infertility, loss of calves, increased culling and the direct costs including labour, insemination and veterinary time were well-recognised by the delegates.
Work is ongoing to update a fertility cost calculator to allow for the various current herd factors, including milk price. Knowing the cost of increasing the calving index can be related, for example, to the margin over purchased feed and in turn related to the feed cost in pence per litre of milk.
The cost of a missed heat and the value of synchronisation can be evaluated from existing herd records so that management developments and proposed changes can be supported economically. Access to the latest developments is available from Dairyworks UK (firstname.lastname@example.org).
The 12th Total Dairy Seminar, in 2017, will be focusing on youngstock, fertility and nutrition. Further details via www.totaldairy.com