Granuloma disease in flocks of productive layers caused by Tetratrichomonas gallinarum.

Granuloma disease in flocks of productive layers caused by Tetratrichomonas gallinarum. Avian Pathol. 2016 Mar 7;:1-44 Authors: Landman WJ, Molenaar RJ, Cian A, van der Heijden HM, Viscogliosi E Abstract In 2013, seven outbreaks of granuloma disease in Dutch flocks of laying chickens occurred. These outbreaks were characterized by increased mortality and high incidence of granulomas, mainly in ceca (340/408 hens = 83%) and livers (69/408 hens = 17%). Mortality started to increase between 21 and 35 weeks of age and reached 9.2% to 12.4% in periods ranging from nine to 48 weeks. Some flocks also showed decreased egg production and/or loss of mean egg weight. All affected flocks were linked to one rearing farm, which therefore seemed to be the source of the disease. However, no signs of disease had been observed at this rearing farm. Sentinel hens placed in one of the affected flocks to determine whether the disease had an infectious nature developed granulomas identical to those seen in the outbreaks. Next, by fulfilling Koch's postulates it was shown that Tetratrichomonas gallinarum was the etiological agent of the granuloma disease. The condition was reproduced in mature SPF White Leghorn hens by inoculation via both, an artificial and a natural route with a well-defined axenic T. gallinarum isolate obtained from one of the affected flocks. Other causes of granuloma disease were excluded. PMID: 26950827 [PubMed - as supplied ...
Source: Avian Pathology - Category: Pathology Authors: Tags: Avian Pathol Source Type: research