July 2012

Helping your Horse Beat the Heat

Summer time brings trail riding, horse shows and hot, humid days. Heat stress is a concern for both riders and their horses. If your horse becomes overheated while you are exercising it, you may notice him feeling weak, tired or listless. If you examine your horse, you will also find your horse's heart rate, respiratory rate and temperature will likely be elevated and in most cases they will be sweating. Your horse's vital parameters will normally be increased after exercise, especially if it is hot out, but they should come down to normal within 15 minutes or so if you are cooling him out appropriately. If they do not, your horse may be experiencing heat stress. If you suspect your horse is having trouble dealing with the heat, move him to a shaded area, offer water to drink, use cool-cold water to hose him, and call your veterinarian if your actions do not seem to be resolving the problem or immediately if your horse seems distressed.

To prevent heat stress, it is recommended that you avoid exercising your horse during the heat of the day, allow your horse to have breaks and cool them out well by walking afterwards. After exercise, allow your horse to have water (small amounts frequently) and bathe him with cool water especially over areas with large muscle like the back and rump, scrape off excess water and repeat as necessary to cool him down. It is important to scrape off the water as it can act as an insulator, preventing heat from dissipating. Do not apply cold towels to the body because they also can act as insulators.

Heat stress can progress to heat stroke. Heat stroke is a dangerous and potentially life threatening condition associated with severe dehydration, depression, elevated respiratory rate, elevated pulse and elevated temperature, shock and possibly coma or death. Veterinary intervention is necessary in cases of heat stroke to prevent death, and includes administration of IV fluids and electrolytes.

Bovine Somatic Cell Count & its Impact

This August marks the start of a lowered Somatic Cell Count (SCC) tolerable threshold. Currently, penalties are being issued when dairy weighted herd average SCC monthly level is above 500,000. The new Penalty level beginning August 1st, 2012 is 400,000. This ensures Canadian producers are keeping up to and possibly surpassing world top standards as Europe also has this penalty level. The 1st penalty will be given to a producer if the weighted average 3 out of 4 consecutive months is greater than 400,000.

During June the dairy task force made up of representatives from DFO, CanWest DHI, OMAFRA, Ontario Veterinary College, SSG solutions and AHL went to 6 different Ontario locations to educate veterinarians and milking equipment service representatives on the fast approaching SCC regulation changes and how to help producers succeed with it. Dairy farms should strive to obtain on average a monthly SCC of 200,000 to ensure that most typical fluctuations will not put them into the penalty range. Smaller herds will fluctuate more month to month as one mastitic cow has a bigger impact on SCC than in a larger herd.

With the penalty level change, producers should take the opportunity to seek areas they can improve within their daily operations. Milking equipment function and cleanliness are an area to investigate. This can be broken down into vacuum function/fluctuation, claw size, milk flow sensor calibration, pulsation, liner replacement interval, and teat dip cup cleaning between milkings. Other areas to consider are lighting in the parlour, cleanliness of udders, teat end health, bucket milker use and cleaning , bedding, cleanliness of calving pen and decreasing heat stress in holding areas. Also, the task force suggested producers should look into monitoring for mastitis in any fresh cows and new additions to the herd.

For more information producers can go to www.scc200.ca or the DFO website for the publications on SCC. Veterinarians have also now been equipped with a Risk assessment checklist similar to the Johne's checklist. This will help producers identify areas of greatest risk within their herd for changes in SCC.

Coccidiosis in Sheep & Goat

Coccidiosis is a very common parasitic disease of young lambs and kids. These organisms survive very well in high moisture conditions and crowding can lead to high burdens in the animals' environment. Infection results in diarrhea, poor growth and potentially death in severe cases. Lambs and kids are susceptible because their immune systems are immature and they become infected by fecal-oral route.

Signs: Signs of disease include depression, diarrhea or runny manure, weight loss, and poor growth. Disease is most often seen at 5 to 8 weeks of age, however can be as early as 3 weeks. Contamination of the environment increases over the lambing/kidding season, which may result in more severe clinical signs and increased mortality later on in the season.

Diagnosis: Coccidiosis can be diagnosed based on clinical signs and from a microscopic fecal exam.

Treatment: Drugs such as sulfonamindes and amprolium are used in the treatment of animals with clinical signs. Preventative medications, called coccidiostats, can be included in the feed, and include lasalocid (Bovatec), monensin (Rumensin) and decoquinate (Deccox).

Prevention: Keeping the environment clean and free of manure, especially the nursing pens and creep feeding areas is very important in the prevention of coccidiosis. Coccidiostats are commonly used in the feed from 2 weeks of age up to 2 to 3 months to allow for immunity to develop. Treating the ewes and does with coccidiostats 30 days pre-partum and avoiding overcrowding can reduce the likelihood of lambs and kids developing illness.