BACKGROUND:  Among infectious diseases, Newcastle disease, due to being highly contagious and its rapid spread among poultry and other bird species, is a deadly viral disease and is considered a global threat to the poultry industry. Objectives: To determine the occurrence of Newcastle disease in poultry broiler farms reported to the Iranian veterinary organization during the study period. Methods: This is a cross-sectional study from September 2013 to March 2015. During this study, from 185 farms and a total of 3700 bird sera, cloacal and tracheal swabs were sampled and tested using a haemagglutination inhibition test and reverse transcriptase polymerase chain reaction respectively. Results: In this study, of a total of 185 farms reported to the Iranian Veterinary Organization, 115 farms (62.16%, 95%CI: 55.17-69.14) were positive for Newcastle disease viruses and then using specific primers, 69 farms (37.3%, 95%CI: 30.33-44.26) had vaccinal pathotype (non-acute) and 46 farms (25%, 95%CI: 18.76-31.23) had acute pathotype (field virus). The mean±SD age of infected poultry was 24.63±5.38 days and antibodies titer against Newcastle disease virus was 5.97±1.21. The highest mortality rates were observed in the spring (32.34%) and winter (26.9%), respectively. Mazandaran (37%) and Isfahan (22%) province had the highest percentage of farms with Newcastle disease. Conclusions: The findings of this study suggested virulent Newcastle virus strains are circulating in the Iranian commercial broiler farms in the mentioned time and with high occurrence. Therefore, the relevant authorities need to make correct decisions to reduce the risk of Newcastle disease in the Iranian poultry industry and its control.

This study was planned to evaluate the extracts of Aloe vera (AV) at three different pH as a growth promoter, immunostimulant and coccidiostat agent in broiler production. This experiment was undertaken for a period of 35 days in the Institute of Animal Sciences, Faculty of Animal Husbandry, University of Agriculture Faisalabad, Pakistan. A total of 150 dayold broiler birds (Cobb) were randomly assigned to 5 treatments with 3 replicates of 10 chicks each. Birds were offered commercial broiler starter and finisher diets supplemented with 100 mg/kg enramycin (ANT), 50 ml/liter AV of pH 3 (AV1), 50 ml/liter AV of pH 7 (AV2), 50 ml/liter AV of pH 12 (AV3) and only fresh clean water (CON).