Ovarian Cysts in Chickens
*K.Merina Devi1, T. Gyaneshori Devi2 and N. Bhumapati3
1*Assistant Professor, Department of Livestock Farm Complex
2Assistant Professor, Department of Livestock Production Management
3Assistant Professor, Department of Veterinary Gyanecology & Obstetrics
COVSc & AH, Central Agricultural University (I), Imphal, Manipur, India
A healthy layer bird normally attains sexual maturity at the age of 18-20 weeks and continue producing eggs economically till they attain 72 weeks of age. During this period, there are many reproductive abnormalities which adversely affect the egg production and mortality of birds, leading to severe economic loss to the farm. One of such reproductive anomalies is ovarian cyst. An ovarian cyst is basically a fluid filled nearly round structure with whitish coloured wall which appears on the surface of ovary. Most ovarian cysts are harmless in nature and can be formed as a result of ovulation. The incidence of ovarian cyst in domestic chicken is very rare, only 10-20 % of aged hens may develop.
The cystic contents may vary from clear watery to mucus in nature. In poultry, cystic condition of right and left oviduct (Goldhaft, 1956) and follicular cysts of ovary (Krishnan, 1967) have been reported, however, the incidence of parovarian cyst in domestic chicken is very rare. In certain case, the cyst may be noticed along with a small cystic dilatation of the right oviduct. The size of the cysts may ranges from a size of a pea to 15 cm or more in diameter. When the size of the cyst is small, the problem is minimal and can be neglected, however, in large size cyst, there may be compression of the nearby abdominal organs leading to distended large abdomen as similar to other cystic conditions of ovary and oviduct (Riddel, 1997).
Also, in large size cyst, the ovary and oviduct may be in quiescent condition that is no signs for the presence of ovarian follicles. On the other hand, in small size cyst, the problem is minimal and can be neglected. The ovarian follicles and left oviduct appears to be apparently healthy and normal, signifying that the egg production of the bird has not been affected.
Causes of ovarian cyst:
The cause of ovarian cyst is not clear, however, there are many predisposed factors to the development of ovarian cyst which may include endocrine disorder, chronic inflammation, metabolic imbalance, anatomical abnormalities and pathological conditions of ovary etc. (Poultry DVM.com)
Signs and symptoms:
Clinical signs may include difficulty in breathing, abdominal distension leading to increase body weight, increase broodiness (nest sitting), inconsistency in egg production followed by complete cessation, depression, avoid to take feed and ultimately death of birds.
Tentative diagnosis can be made by clinical signs as mentioned above. Radiography and ultrasonography will often reveal the fluid-filled cyst close to ovary.
Supportive treatment can be given in the form of providing less stress to the affected bird, easy access to feed and water and isolation of the sick bird. Transabdominal aspiration via ultrasound, celiotomy or endoscopy can be performed. For treatment of a bird, such complicated and cost effective approach is not advisable, the best is to cull (remove) the affected bird from the flock.
Appearance of ovarian cyst in chicken is a rare incidence and there is very few literatures available so far. However, ovarian cyst, in some or other ways, not only leads to decline in egg production but also causes mortality in layer bird.
- Goldhaft, T.M. 1956. Cystic oviducts in domestic fowls. Cornell Vet., 46: 223 – 227
- Krishnan, R. 1967. Follicular cysts (ovarian cysts) in Fowls. Indain Vet. J., 44: 651- 661.
- P.Srinivasan and G.A. Balasubramaniam, 2012. Parovarian cyst in layer chicken. Tamilnadu J. Veterinary & Animal Sciences 8 (1) 26-28.
- Riddel, C.1997. Diseases of Poultry. 10th Edn., Edited by B.W. Calnek, Iowa State University Press. Ames. Iowa, USA, pp: 940.
- www.Poultry DVM.com. Ovarian cyst in chicken.