Three key poultry diseases have resulted in losses of chickens and turkeys destined for the Christmas market, according to the latest Veterinary Laboratories Agency monthly surveillance report.
Any serious escalation of these losses from erysipelas, Blackhead and Mycoplasma could affect the cost of turkeys at Christmas, said the Agency.
In the first case, the Royal Veterinary College, Hertfordshire, diagnosed septicaemia caused by erysipelas, as the cause of death in five turkeys out of 520 that were due to be slaughtered at the beginning of December.
It is a sudden onset bacterial infection seen in turkeys and increasingly in free-range chickens. The bacterium is fairly resistant to environmental effects or disinfectants and may persist in alkaline soil for years. There is likely to be an increased risk if housing or land has been previously used by pigs or sheep.
The Langford office, near Bristol, of the VLA reported four separate outbreaks of Blackhead affecting growing poults. Blackhead is a disease caused by protozoan Histomonas meleagridis which affects the lower digestive tract, said the Agency.
Clinical signs are non-specific and birds may exhibit some or all of the following: A stilted gait when walking, loss of interest in food, wasting, and yellow droppings, occasionally darkening of the skin and wattles, and death. The darkening of skin and wattles on the head provides the common name of “blackhead”.
Currently, there are no authorised treatments available to prevent the disease, but good biosecurity is a key factor in preventing the spread of this disease.
And finally, the Shrewsbury office investigated the deaths of 10 birds from a group of 120 broilers, which had been on the farm for 2-3 weeks. They were eight-week-old birds for the Christmas market and were diagnosed with Mycoplasma gallisepticum.
Mycoplasma are easily killed by disinfectants, heat, sunlight, and only remain viable in the environment, outside the bird, for up to three days. For this reason, it is fairly easy to eliminate on single-age, all-in all-out poultry units.