Isolation and characterization of genotype VII Newcastle disease virus from NDV vaccinated farms in Malaysia

Molecular analysis, particularly sub-genotype classification, and study on the relationship of recent Malaysian NDVs with other isolates from around the world are lacking. Therefore, in the present study, a molecular epidemiological investigation was conducted to characterise six Newcastle disease viruses (NDV) isolated between 2014 and 2015 from vaccinated commercial poultry flocks. Partial Fusion (F) and Hemagglutinin-neuraminidase (HN) genes were amplified from IBS046/2014, IBS060/2014, IBS061/2014, IBS074/2014, IBS160/2015, and IBS162A/2015 isolates using one-step reverse transcription polymerase chain reaction (RT-PCR), sequenced and phylogenetically analysed. Sequence and phylogenetic analysis revealed that all the recently isolated strains of NDV belonged to sub-genotype VIIa and lineage 5a. Moreover, deduced amino acid sequence at the F protein cleavage site of the isolates revealed either 112RRQKRF117 or 112KRRKRF117 consistent with the motif found in velogenic pathotypes. The study concluded that the genotype VIIa was the causative agent of recent ND outbreaks in vaccinated broiler flocks from Malaysia. Interestingly, five out of the six isolates characterised in this study had a unique F0 protein cleavage site (112KRRKRF117). Further studies are required to determine the role of these motifs on the virulent potential of the isolates

Growth performance, intestinal morphology, and carcass traits in broiler chicken fed Conocarpus erectus leaf meal

This study evaluated the effects of adding Conocarpus erectus leaf meal to the diet on the perfor-mance, carcass traits, organ weights, and intestinal morphology of broiler chicken. A total of 396 one-day-old Ross 308 broilers were assigned to nine treatments, which included 0, 0.25%, 0.5%, 0.75%, 1%, 1.25%, 1.5%, 1.75%, and 2% C. erectus leaf meal addition to the broiler diet. Feed and bird weights were recorded weekly. On slaughter day, the weights of carcasses and organs were individual-ly reported using a digital scale as well as the intestine samples were pooled for tissue analysis. High levels of C. erectus leaf meal reduced (P<0.01) body weight, body weight gain, and feed conversion ratio. The basal diet and 0.25% C. erectus leaf meal diet reported higher (P<0.01) body weight and body weight gain than did the other treatments. Birds fed 0.25% C. erectus leaf meal supplementation performed similarly to those fed the basal diet. Significantly, with increasing amounts of C. erectus leaf meal in the diets, there was a linear slope decrease in live weight and body weight gain as well as a linear slope rise in the values of feed intake and feed conversion ratio. Carcass trait and relative organ weights were not altered among the dietary treatments. Feeding 1% C. erectus leaf meal diet decreased (P<0.01) relative abdominal fat weight compared to birds fed the control diet. Birds fed dietary C. erectus treatments had higher (P<0.01) villus height, villus width, crypt depth, and lower villus height/crypt depth ratio than did birds fed the control diet. In conclusion, the study indicated that feeding 0.25% C. erectus leaf meal showed no deleterious effects on the growth performance of the broiler. Growth performance and intestinal morphology were linearly reduced when broilers were fed up 2% of C. erectus meal