Newsletter February 2018
Treatment and Prevention of Heat Stress in Poultry
Most parts of chicken producing areas in South Africa are prone to heat stress conditions during summer months. Heat stress conditions are present when temperature around the chickens increase past 30 deg C. The production losses caused by heat stress to egg production and weight gain are underestimated by producers. It was determined in controlled layer studies that egg production drop by 13.2% and 26% respectively for heat stress periods of 8-14 days and 30-42 days. Egg weight reduced by 3.2% with poor shell and bone strength. In another study over 12 days it was found that feed intake in laying hens reduce by 28.5 grams per day with a drop in production of 36%. In broilers a reduction of 17% in weight gain and 15% in feed intake was observed at temperatures of 33% over a two week period. During heat stress conditions the birds will increase their breathing from 37 breaths per minute to 250 breaths per minute. This leads to a build up of carbon dioxide and an increase in blood plasma pH (and reduction of cell pH) with increase in urine output with resultant loss of electrolytes and bicarbonate. Stress hormones appear in blood and heat shock proteins are activated to protect heat sensitive tissues. During heat stress birds drinks more and eat less. Appetite is depressed by 1.5% for each degree of temperature rise above 20 deg C. Typical signs of heat stress is Panting, Wings Spreading, Lethargy, Convulsions, Cannibalism, Wet Droppings, Mortality Increase, Slow Growth, Drop in Egg Production and Reduced Bone Mineralization. Various studies showed that supplementation of ascorbic acid not only prevent cell oxidative damage but also reduce the increase in corticosterone and heat shock protein 70 (hsp70). These studies conclude that the addition of ascorbic acid to water will lead to a less severe response of birds to high temperatures. The Heat Stress Hydration Pack supplied by Super Agri Science not only contains Ascorbic Acid but also Sodium Bicarbonate and Potassium sulphate for the supplementation of ascorbic acid, bicarbonate and electrolytes to prevent production losses during heat stress conditions. Apply at a rate of 5 litres per 1,000 litres water for 3 – 5 days during heat stress conditions to allow a reduced heat stress response and prevent production losses.
Avian Influenza survival rate at different temperatures? – Winter is Coming!
Various studies by Kurmi et al and Lu et al showed that the influenza virus has a short life span of about 24 hours at temperatures above 28 degrees Celsius. They further showed that at temperatures of 4 deg and 24 deg C the virus will survive for 8 weeks and 5 days respectively. It can thus be concluded that at low environmental temperatures the Avian Influenza virus can survive for various days and even weeks. Vigilance and prevention strategies during winter months should thus be strengthened to prevent any access and contamination of poultry houses and sites with wild bird droppings, infected chicken manure and pests that could carry the virus into the houses.
Product Focus – Eliminator, effective site disinfectant
Eliminator is a powdered product that is not only used to treat wet and rotting
manure areas inside and outside chicken houses but is also used as a general site disinfectant to eliminate wild bird droppings outside chicken houses. This combination product will coagulate, denature an dry any organic material it has contact with and showed a 99,9% kill rate of the common pathogens.
Spread around chicken houses, ablution blocks and on walkways and use as dry footbath for an effective tool to prevent infected organic material from entering the chicken houses.