ABSTRACT Most of the neoplastic diseases affecting poultry have a viral etiology, such as Marek’s disease, avian leukosis/sarcoma and reticuloendotheliosis. In the present paper, histopathology and molecular methods were performed, in addition of necropsy and gross morphology evaluation, for the differential diagnosis of these diseases in two green peafowls (Pavo muticus). The affected birds showed non-specific signs, such as depression, anorexia, and diarrhea. At necropsy, diffuse enlargement by several times the normal size of the liver and the spleen was observed. In one of the birds, the liver presented white to grayish discoloration was present, and focal and nodular growths in the other bird. Grossly, the other visceral organs and the peripheral nerves were normal. Microscopically, most of the tumor cells were large and uniform with pleomorphic nuclei. The PCR analysis for Marek’s disease virus (MDV), avian leukosis virus (ALV), lymphoproliferative disease virus (LPDV), and reticuloendotheliosis virus (REV)based on their specific sequences showed the presence of ALV subgroups A-E and REV. According to these results, definitive diagnosis was co-infection of ALV and REV in naturally-infected green peafowls.

SUMMARY This experiment was carried out to evaluate the effects of four levels of dietary threonine (Thr) supplementations on growth performance, gut size and histomorphometric alterations of small intestines in broiler chicks in 1-14 days. Two hundred eighty-eight Ross 308 one-day-old male broiler chicks were randomly assigned to four treatments with six replicates (12 birds per replication) received a common diet based on corn, wheat and soybean meal that met nutrients requirement of Ross 308. Birds were fed dietary treatments consisting of four levels of standardized digestible (SD) Thr: control diets (Basal diets) containing 0.65% SD Thr, 0.89% SD Thr (nutrients requirement of Ross 308), 0.93% and 0.97% SD Thr. Body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) were measured at 1, 7 and 14 days old. Morphometric analysis of small intestine was carried out to investigate the effect of Thr levels on development of small intestines in starter period of broiler chicks. Results indicated that Thr levels improved FCR (quadratic effect, p=0.044) and BWG (quadratic effect, p=0.0009) for broilers given the diets containing 0.89% SD Thr in the starter period compared to other treatments (p<0.05). Furthermore, villus height and muscular thickness in duodenumand muscular thickness in jejunum were increased by this treatment (p<0.05). Villus width was increased by Thr treatments comparing to control group, as well. In conclusion, broiler performance and intestinal morphometry were improved by Thr supplementation which were efficiently obtained by 0.89% SD Thr in the first two weeks of the broiler´s diet.