Putative human and avian risk factors for avian influenza virus infections in backyard poultry in Egypt

Highly pathogenic influenza A virus subtype H5N1 causes significant poultry mortality in the six countries where it is endemic and can also infect humans. Egypt has reported the third highest number of poultry outbreaks (n = 1084) globally. The objective of this cross-sectional study was to identify putative risk factors for H5N1 infections in backyard poultry in 16 villages in Damietta, El Gharbia, Fayoum, and Menofia governorates from 2010–2012. Cloacal and tracheal swabs and serum samples from domestic (n = 1242) and wild birds (n = 807) were tested for H5N1 via RT-PCR and hemagglutination inhibition, respectively. We measured poultry rearing practices with questionnaires (n = 306 households) and contact rates among domestic and wild bird species with scan sampling. Domestic birds (chickens, ducks, and geese, n = 51) in three governorates tested positive for H5N1 by PCR or serology. A regression model identified a significant correlation between H5N1 in poultry and the practice of disposing of dead poultry and poultry feces in the garbage (F = 15.7, p < 0.0001). In addition, contact between domestic and wild birds was more frequent in villages where we detected H5N1 in backyard flocks (F = 29.5, p < 0.0001).     

A comparative study of pigeons and chickens experimentally infected with PPMV-1 to determine antigenic relationships between PPMV-1 and NDV strains

To compare the pathogenicity of PPMV-1 in pigeons and chickens, both species of birds were experimentally infected with strain pi/CH/LHLJ/110822, which was isolated from a pigeon in China. The clinical signs, gross lesions, and histopathological changes were observed in pigeons inoculated with pi/CH/LHLJ/110822. The morbidity and mortality rates were 80% and 70% in pigeons, respectively, whereas there were no clinical signs or gross lesions in chickens inoculated with the same strain. The viral loads in tissue samples were detected by real-time RT-PCR, indicating that six tissue samples (i.e., kidney, lung, brain, trachea, Harderian glands, and proventriculus) had detectable viral RNA in all dead pigeons, and significant differences in viral loads between pigeons and chickens were observed in several tissue samples (i.e., Harderian glands, proventriculus, duodenum, pancreas, small intestine, and large intestine) on 3 days post-inoculation (dpi) and in brain tissue on 7 dpi. In general, viral loads in pigeons were higher than those in chickens, whereas antibody titers in pigeons were lower than those in chickens. These results showed differences in pathogenicity, efficiency of viral RNA replication, and humoral immunity, indicating different susceptibilities between the host species. Additionally, the cross hemagglutination inhibition assay and cross virus neutralization tests demonstrated that pi/CH/LHLJ/110822 antigenicity was different from those of strains La Sota and F48E9.     

桑1-脱氧野尻霉素降血糖作用的研究进展

1-脱氧野尻霉素是桑树中的一种生物碱,是哺乳动物α-葡萄糖苷酶的有效抑制剂,具有降糖、降脂、抗病毒、抗肿瘤等药理作用。本文针对已报道的1-脱氧野尻霉素功能,综述了近年来1-脱氧野尻霉素降糖作用研究的最新进展,为更好利用和开发桑叶1-脱氧野尻霉素提供参考。     

Comparative Analysis of mRNA Expression of Surface Antigens between Histiocytic and Nonhistiocytic Sarcoma in Dogs

Background

Definitive diagnosis of histiocytic sarcoma (HS) in dogs is relatively difficult by conventional histopathological examination because objective features of HS are not well defined.

Hypothesis

Quantitative analysis of mRNA expression of selected cellular surface antigens (SAs) specific to HS in dogs can facilitate objective and rapid diagnosis.

Animals

Dogs with HS (n = 30) and dogs without HS (n = 36), including those with other forms of lymphoma (n = 4), inflammatory diseases (n = 6), and other malignant neoplasias (n = 26).

Methods

Retrospective clinical observational study. Specimens were collected by excisional biopsy, needle core biopsy, or fine needle aspiration. To determine HS detection efficacy, mRNA expression levels of selected SAs specific to HS in dogs, including MHC class IIα, CD11b, CD11c, and CD86, were quantitatively analyzed using real‐time quantitative polymerase chain reaction.

Results

Each SA mRNA expression level was significantly higher in HS dogs than in non‐HS dogs (P = .0082). Cutoff values for discriminating between HS and non‐HS dogs based on these expression levels were calculated on the basis of receiver‐operating characteristic analysis. Accuracy of the cutoff values, including MHC class IIα, CD11b, CD11c, and CD86, was 87.9, 86.4, 86.4, and 84.8%, respectively.

Conclusions and Clinical Importance

Our results suggest that quantitative analysis of mRNA expression of the selected SAs could be an adjunctive diagnostic technique with high diagnostic accuracy for HS in dogs. Substantial investigation is required for exclusion of diseases with similar cell types of origin to lymphoma.     

Effects of pre‐partum milking of dairy cows on calcium metabolism at start of milking and at calving

This experiment studied the effect of pre‐partal milk removal on calcium metabolism at start of milking and at calving. Nine cows of the Swedish Red breed were milked for 1–7 days pre‐partum. The average milk yield at the first milking was 4.8 l, and the average yield the last day prior to calving was 13.4 l. Five cows were used as control cows and were only milked post‐partum. Samples of plasma and urine were taken to determine the effect of pre‐partum milking and calving on levels of calcium, magnesium, parathyroid hormone and plasma C‐terminal crosslinked telopeptide of type 1‐collagen (CTx), used as a marker of bone resorption. Pre‐partum milking resulted in a decrease in plasma calcium that was evident 2 days after the first milking. Parathyroid hormone increased at the same time, and CTx started to increase from 24 h after the first milking. There were no effects on plasma magnesium or urinary output of calcium or magnesium. The first week after calving, there were no differences between pre‐partum milked cows and control cows in plasma or urine variables, or in milk yield. In conclusion, pre‐partum milking activated the calcium‐restoring mechanisms but did not improve calcium status at calving.     

Relationship of Progesterone,Bovine Pregnancy-Associated Glycoprotein-1 and Nitric Oxide with Late Embryonic and Early Fetal Mortalities in Dairy Cows

The aim of the present study was to determine the relationship of progesterone (P4), bovine pregnancy-associated glycoprotein-1 (bPAG-1) and nitric oxide (NO) levels with late embryonic (LEM; day 28 to day 42) and early fetal mortalities (EFM; > day 42 to day 56) in dairy cows. Transrectal ultrasonography (6–8 MHz) was performed in 100 Holstein-Friesian cows at days 28, 42 and 56 after artificial insemination (AI; day 0) to diagnose pregnancy and to monitor the fate of the embryo. After ultrasound scanning of each cow, a milk sample was collected for assessment of P4 by an ELISA test and a blood sample was collected for assessment of bPAG-1, by using a double-antibody radioimmunoassay, and serum NO metabolites (nitrate + nitrite). Based on ultrasonographic examinations and bPAG-1-RIA, 41 of 100 inseminated cows were confirmed pregnant at day 28 after AI. Nine cows suffered of LEM, and 6 cows suffered of EFM and the overall pregnancy loss rate was 36.6% (15/41) between days 28 and 56 of pregnancy. By logistic regression analysis, there were no significant relationships between the level of P4 and bPAG-1 at day 28 after AI and the occurrence of LEM and EFM. Also, there were no significant relationships between the levels of P4 and bPAG-1 at day 42 and the occurrence of EFM. On the other hand, a significant relationship (P<0.05) was found between NO level at day 28 and the occurrence of LEM. In conclusion, measurement of the serum NO concentration at day 28 of pregnancy might help to predict the outcome of pregnancy by day 42 in dairy cows but further studies are needed to confirm this.     

Genetic variation in the ovine uncoupling protein 1 gene: association with carcass traits in New Zealand (NZ) Romney sheep,but no association with growth traits in either NZ Romney or NZ Suffolk sheep

The uncoupling protein 1 (UCP1) plays an important role in the regulation of lipolysis and thermogenesis in adipose tissues. Genetic variation within three regions (the promoter, intron 2 and exon 5) of the ovine UCP1 gene (UCP1) was investigated using polymerase chain reaction‐single‐strand conformational polymorphism (PCR‐SSCP) analyses. These revealed three promoter variants (designated A, B and C) and two intron 2 variants (a and b). The association of this genetic variation with variation in lamb carcass traits and postweaning growth was investigated in New Zealand (NZ) Romney and Suffolk sheep. The presence of B in a lamb's genotype was associated with decreased subcutaneous carcass fat depth (V‐GR) (p = 0.004) and proportion of total lean meat yield of loin meat (p = 0.005), and an increased proportion of total lean meat yield of hind‐leg meat (p = 0.018). In contrast, having two copies of C was associated with increased V‐GR (p < 0.001) and proportion of total lean meat yield of shoulder meat (p = 0.009), and a decreased hind‐leg yield (p = 0.032). No associations were found with postweaning growth. These results suggest that ovine UCP1 is a potential gene marker for carcass traits.     

Volatile fatty acid profile for grass hay or alfalfa hay fed to alpacas (Vicugna pacos)

The purpose of this study was to determine the diurnal composition and concentration of volatile fatty acids (VFA) and to determine VFA composition and concentration differences between stomach compartment 1 (C1) and caecum of alpacas fed grass and alfalfa hay. The study was divided into two experiments. In Experiment 1 (EXP 1), 10 male alpacas (3+ years old, 65 kg BW) were divided into two groups, housed in drylot pens, provided ad libitum water and fed alfalfa (AH) or grass hay (GH) for 30 days. The alpacas were slaughtered and the digestive tract collected, divided into sub‐tract sections, weighed and digesta sampled for pH, dry matter (DM) and NDF. Volatile fatty acid composition and concentration were determined on C1 and caecal material. Four adult male (3+ years old, 60 kg BW), C1 fistulated alpacas were housed in metabolism crates and divided into two forage groups for Experiment 2 (EXP 2). Alpacas were fed the forages as in EXP 1. Diurnal C1 VFA samples were drawn at 1, 3, 6, 9, 12, 18 and 24 h post‐feeding. There were no differences between forages for tract weight, C1 and caecum digesta DM or NDF. Differences were noted (p < 0.05) for pH between forages and sub‐tract site. Volatile fatty acids concentrations were different (p < 0.05) for forage and site, and total VFA was higher for AH than GH (110.6 and 79.1 mm ) and C1 than caecum (40.7 and 27.6 mm ). Proportion of VFA was significant (p < 0.05) for forage and site, C1 acetate highest for GH (84.8 vs. 74.0 mm ) and caecum acetate 83.7 and 76.2 mm for GH and AH respectively. These data demonstrate the level of VFA produced in C1 and the caecum of alpacas and the diurnal VFA patterns. Composition of VFA is similar to other ruminant species.     

布鲁菌感染小鼠RAW264．7细胞对IRGl基因的表达调控作用

针对小鼠RAW264．7细胞IRGl基N设计4个RNA干扰靶位,筛选出最佳干扰序列构建shRNA慢病毒载体质粒并包装获得慢病毒颗粒,进而经嘌呤霉素筛选获得稳转细胞系,实现IRGl基因在RAW264．7细胞基因表达的沉默。并通过布鲁菌l6M株及M5株感染基因沉默细胞对IRGl基因在布鲁菌感染中的作用进行研究。结果表明,慢病毒介导的shRNA高效、稳定地沉默了IRGl基因的表达,布鲁菌侵染RAW264．7细胞后IRGl基因表达上调。未试验为1RG1基因及相美调控基因抗布鲁菌病作用研究奠定了基础。