A growing problem amongst backyard hens, most commonly attributable to the over-feeding of scraps and mixed corn. As a rule, the average adult hybrid hen should be fed 125g layers pellets/day, with 200ml water/day (fresh water should be accessible throughout the day), with a little grit provided and a small amount of mixed corn. Corn is best fed in the afternoon to ensure that the birds do not gorge and fill themselves on it first thing in the morning, which leads to a decreased intake of layers mash/pellets. Obesity in chickens can lead to a decline or even cease in egg production, as well as putting the birds at a higher risk of egg binding.
Egg Yolk Peritonitis (EYP)
It is rare for backyard hybrid hens to suffer actual egg binding, especially if an adult laying bird. What is far more common is a condition known as ‘Egg Yolk Peritonitis’ or ‘EYP.’
This condition arises when the egg produced and released from the hen’s ovary fails to reach the oviduct, where the egg would normally then travel down and develop until being laid. In EYP, the early-stage egg ends up within the abdominal cavity (called the ‘coelom’ in birds) and sets up an infection thought to be most often caused by E.coli, leading to peritonitis which is often fatal. Fluids, nursing support and antibiotics are considered the current best therapy.
May be attributable to a number of factors, including:
- Lack of space
- Lack of necessary nutritional components (eg protein) Lack of dust bath availability
- Sudden introduction of new birds to the flock
This common condition, also known as plantar pododermatitis, is a condition seen in most species of kept birds, including poultry. The condition manifests itself in initially small, nodular, inflammed sores on the underside of the chicken’s feet. If left untreated, these can quickly progress to more aggressive lesions, being of great discomfort to the bird and potentially risking systemic infection and even, in the most extreme cases, death. Although diet has a very important role to play in the maintenance of healthy feet, the other main factor that has been readily identified as a major contributor to bumblefoot is perching quality. Recent studies have indicated that thinner cylindrical perches only provide a rather narrow point of contact between the perch and the bird, leading to high contact pressure on the undersides of the feet and on the bird’s keel (breastbone). The current advise for the provision of perching to your hens is flatter, more cuboidal perches (with rounded corners) or much wider cylindrical perches – tree branches being optimal due to the non-uniformity of them allowing a range of perching stances.
Marek’s disease is caused by a herpes virus, and was the first virus to be associated with cancer development in animals. Usually affecting younger birds (up to six months of age), with a mortality rate of up to 100%, this disease has a strong breed predisposition, including the following:
There are two forms in which the virus manifests itself:
- Acute – causing cancerous change to the liver and spleen, leading to diarrhoea and stunted growth
- Classic – causing a ‘drunken’ unstable gait, affecting both the legs and wings.
There is not yet a successful treatment available for the disease, and diagnosis of Marek’s is usually reached upon post mortem examination of the affected bird(s).
Red Mite (dermanyssus gallinae)
A very common problem amongst backyard poultry; red mite infestations can be incredibly challenging to eliminate. At only the size of a pinhead, these parasites are just visible to the naked eye, more so when clumped into a mass, often seen during the day in the corners of the coop when they are not feeding on the chickens.
The most important factor to remember about red mites is that they do not live on the hosts themselves, unlike lice and the Northern Fowl Mite Ornithonysuss sylviarum, which live on the host birds for all stages of the life cycle. This means that if faced with a red mite infestation, examining the birds themselves will not uncover the mites. They spend the day hidden in the crevices of the coops, waiting to feed on the hens at night as they roost. If the infestation is severe enough, the hens may even become anaemic (loss of red blood cells).
The mites themselves may survive for up to 36 weeks in the coop without feeding, and as such treatment regimens can be complex, and must be tailored to each individual flock. As a general rule, plastic coops provide less opportunity for the mites to hide and a better chance of ridding an infestation, but each situation must be approached with tailored veterinary advice.