Serological and phylogenetic analysis indicating prevalence of fowl adenovirus in China
Fowl adenoviruses (FAdVs), which belong to the genus  Aviadenovirus  in the Adenoviridae family, are grouped into five species named Fowl adenovirus A–E ( FAdV-A to FAdV - E ) and 12 serotypes (1–11, 8a, 8b) based on genome sequencing and virus neutralisation, respectively. FAdVs are responsible for a wide range of clinical signs, including hydropericardium-hepatitis syndrome (HHS), inclusion body hepatitis (IBH) and gizzard erosion (GE).1 HHS is primarily caused by the FAdV-4 serotype and causes more than 30 per cent mortality.2 3 IBH is related to the multiserotype of FAdVs and leads to 10–30 per cent mortality in chickens. Some FAdV-1 strains are responsible for GE.1 3

Cases of IBH or HHS have been increasing rapidly, resulting in great economic losses worldwide.3–8 In the present study, we determined the prevalence of FAdV infections in chicken flocks in China by serological analysis and characterised the genotypic distribution among the FAdV strains previously reported in China in GenBank database by phylogenetic analysis. Our findings could provide implications for a promising control measure and vaccination strategy for FAdV infection in the poultry industry.

To evaluate the prevalence of FAdV infections in China, a total of 4544 serum samples were collected from 119 different non-vaccinated chicken flocks in 2014–2016. These samples were localised in 13 provinces or cities in …
Fowl Adenovirus Serotype 4 Influences Arginine Metabolism to Benefit Replication
SUMMARY. Hydropericardium syndrome (HPS) is caused by fowl adenovirus serotype 4 (FAdV-4). HPS has caused outbreaks in Chinese populations of broiler chickens since 2015. However, little is known about the molecular mechanisms underlying HPS. In this study, we used transcriptomic analysis to screen differentially expressed genes (DEGs) in the livers of FAdV-4–infected and noninfected chicks. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the gene network associated with the arginine metabolism pathway was enriched in livers infected by FAdV-4; 10 genes were downregulated and 8 genes were upregulated in these livers when compared to noninfected livers. The DEGs identified in livers were reanalyzed by real-time fluorescence quantitative PCR (qPCR); results indicated that the mRNA levels of the DEGs concurred with the data derived from KEGG analysis. Next, we used qPCR to detect the DEGs of the arginine metabolism pathway in a hepatocellular carcinoma cell line (LMH) after infection with FAdV-4 for 24 hr; this also indicated that the mRNA levels of the DEGs concurred with that seen in the liver. We also used si-RNA oligonucleotides to knock down the mRNA levels of iNOS in LMH cells infected with FAdV-4 and found that the viral load of FAdV-4 was increased. Further investigation revealed that the addition of 240 µg/ml of arginine into the culture medium of LMH cells infected with FAdV-4 for 24 hr led to a significant increase in the mRNA levels of iNOS but a significant reduction in the viral load of FAdV-4. Therefore, our data indicated that when broiler chickens become infected with FAdV-4, the arginine metabolic pathway in the liver becomes dysfunctional and the iNOS mRNA level decreases. This will add benefit to the replication of FAdV-4 but can be inhibited by the addition of an appropriate amount of arginine.
Hill country sheep production. I. The influence of age, flock, and year on some components of reproduction rate in Romney and Border Leicester × Romney ewes.
Data from 7,091 straightbred Romney and Border Leicester × Romney ewes grazed at the Whatawhata Hill Country Research Station over the period 1959 to 1967 have been used to obtain estimates of flock and age-of-ewe effects on reproduction rate and its components and of year-to-year variation. The ewes were from six groups: a Romney control (RCR) flock, a Romney flock in which ewes were mated either to Romney (RER) or to Border Leicester rams (REB), and flocks of first-cross (F1), second-cross (F2), and third-cross (F3) Border Leicester × Romney ewes mated to first-cross Border Leicester × Romney rams. The ewes' ages at lambing varied from 2 to 5 years and no selection was practised. The ratio of number of lambs weaned per ewe present at lambing increased from the RCR (0.84) to the F1 (1.07), then declined with interbreeding to the F2 (0.92) and further to the F3 (0.87) ewes. Similar changes were evident for the percentage of ewes lambing, of multiple births, and of lambs surviving to weaning. Over...