Characterisation of gastrointestinal helminths and their impact in commercial small-scale chicken flocks in the Mekong Delta of Vietnam

Tropical Animal Health and Production - Commercial small-scale chicken farms managed as all-in-all-out but operating with low standards of hygiene/biosecurity are increasingly common in Vietnam....     

Selection based on morphological features of porcine embryos produced by in vitro fertilization: Timing of early cleavages and the effect of polyspermy

The aim of this study was to examine whether a morphological approach is efficient for selecting high‐quality porcine embryos produced by in vitro fertilization (IVF) under high polyspermy conditions. Frozen‐thawed Meishan epididymal spermatozoa showing moderate and high polyspermy were subjected to IVF (1 × 10⁵ sperms/ml). Under conditions of moderate polyspermy, 4‐cell embryos selected at 48 hr after IVF (single selection) and 8‐cell embryos selected at 79 hr after IVF from the collected 4‐cell embryos (double selection) showed high developmental competence. Likewise, 4‐ and 8‐cell embryos produced by IVF under high polyspermy conditions also showed high competence for development to blastocysts. However, blastocysts derived from high polyspermy conditions had significantly fewer cells than those produced under moderate polyspermy conditions. Furthermore, the frequency of nuclear and chromosomal abnormalities in 4‐ and 8‐cell embryos produced under conditions of high polyspermy was significantly (p < .05) higher in comparison to moderate polyspermy conditions. These findings suggest that although high polyspermy affects the frequency of nuclear and chromosomal anomalies in porcine IVF embryos, subsequent selection based on morphological features of 4‐ and 8‐cell embryos even under high polyspermy conditions, could be an alternative option for selecting porcine IVF embryos with high development ability.     

Characteristic features of porcine endogenous retroviruses in Vietnamese native pigs

We aimed to clarify the genomic characteristics of porcine endogenous retroviruses (PERVs) in Vietnamese native pig (VnP) breeds. First, we investigated genetic polymorphisms in β‐ and γ‐like PERVs, and we then measured the copy numbers of infectious γ‐like PERVs (PERV‐A, B, and C). We purified genomic DNA from 15 VnP breeds from 12 regions all over the country and three Western pig breeds as controls, and investigated genetic polymorphisms in all known PERVs, including the beta (β)1–4 and gamma (γ)1–5 groups. PERVs of β1, β2, β3, and γ4 were highly polymorphic with VnP‐specific haplotypes. We did not identify genetic polymorphisms in β4, γ1, or γ2 PERVs. We then applied a real‐time polymerase chain reaction–based method to estimate copy numbers of the gag, pol, and env genes of γ1 PERVs (defined as A, B, and C). VnP breeds showed significantly lower copy number of the PERV genes compared with the Western pig breeds (on average, 16.2 and 35.7 copies, respectively, p < .05). Two VnP breeds showed significantly higher copy number compared with the other VnPs (p < .05). Our results elucidated that VnPs have specific haplotypes and a low copy number of PERV genes.     

Examination of milk microbiota,fecal microbiota,and blood metabolites of Jersey cows in cool and hot seasons

Microbiota of individual cow milk, bulk tank milk, and feces of Jersey cows were examined. Samples were collected from two farms (F1 and F2) in cool (November, Nov) and hot (July, Jul) seasons. Milk yield and milk composition were similar between the two farms and between the two seasons. Prevalent taxa of the fecal microbiota, i.e. Ruminococcaceae, Bacteroidaceae, Lachnospiraceae, Rikenellaceae, and Clostridiaceae, were unaffected by the farm and season. Relative abundance of milk microbiota for Pseudomonadaceae, Enterobacteriaceae, and Streptococcaceae (F1 > F2) and Lactobacillaceae, Bifidobacteriaceae, and Cellulomonadaceae (F1 < F2) were different between the two farms, and those for Staphylococcaceae, Bacillaceae, Ruminococcaceae, and Veillonellaceae (Nov < Jul) and Methylobacteriaceae and Moraxellaceae (Nov > Jul) were different between the two seasons. The microbiota of bulk tank milk was numerically different from that of individual cow milk. Principal coordinate analysis indicated that the milk microbiota was unrelated to the fecal microbiota. The finding that relative abundance of Pseudomonadaceae and Moraxellaceae appeared greater than those reported for Holstein milk suggested that higher protein and fat content may result in a greater abundance of proteolytic and lipolytic taxa in Jersey cow milk.     

Surveillance of swine influenza viruses in sentinel familial farms in Hung Yen province in Northern Vietnam in 2013–2014

From May 2013 to April 2014, 15 swine family‐run farms (17 pig litters) in two districts in Hung Yen province, near Hanoi, were virologically and epizootiologically monitored for swine influenza viruses (SIV) monthly. No SIV was isolated from nasal swabs. Maternal antibodies were detected in 10 litters, and seroconversion against SIV was detected in six litters. There was a marked difference in patterns of SIV transmission in the two districts. Van Lam district which has low density of swine with mainly smallholder farms had low intensity of SIV, with much of the infection caused by H1N1 2009 pandemic‐like viruses A(H1N1)pdm09, likely originated from humans. In contrast, Van Giang district, which has high swine density and larger farms, had high levels of typical SIV (triple reassortants H3N2 and H3N2 Binh Duong lineage viruses) circulating within swine. With one exception, the SIV lineages detected were those we concurrently isolated from studies in a large central abattoir in Hanoi. Influenza‐like illness symptoms reported by farmers were poorly correlated with serological evidence of SIV infection.     

Influence of SHIP on the NK repertoire and allogeneic bone marrow transplantation

Natural killer cell (NK) receptors for major histocompatibility complex (MHC) class I influence engraftment and graft-versus-tumor effects after allogeneic bone marrow transplantation. We find that SH2-containing inositol phosphatase (SHIP) influences the repertoire of NK receptors. In adult SHIP-/- mice, the NK compartment is dominated by cells that express two inhibitory receptors capable of binding either self or allogeneic MHC ligands. This promiscuous repertoire has significant functional consequences, because SHIP-/- mice fail to reject fully mismatched allogeneic marrow grafts and show enhanced survival after such transplants. Thus, SHIP plays an important role in two processes that limit the success of allogeneic marrow transplantation: graft rejection and graft-versus-host disease.     

A comparative efficacy test of 1 versus 2 doses of CIRCOQ PCV2 subunit vaccine against naturally occurring PCV2-type d in piglets with high maternally derived antibodies (MDAs) on a Vietnamese swine farm

The aim of this study was to evaluate the protective efficacy of the CIRCOQ porcine circovirus type 2 (PCV2) subunit vaccine in piglets with high maternally derived antibodies (MDAs) against disease caused by natural infection with PCV2d. A total of 130 weaned, 21-day-old healthy pigs was allocated into 3 trial groups. The signs of respiratory disorder were higher in unvaccinated pigs than in vaccinated pigs at 13 to 17 weeks old (P < 0.05), 18 to 22 weeks old (P < 0.001), and 23 to 27 weeks old (P < 0.01). The unvaccinated pigs had an early rate of dermatitis at 8 to 12 weeks old (10.0%), 13 to 17 weeks old (30.0%), 18 to 22 weeks old (46.7%), and 23 to 27 weeks old (33.3%), while there were no cases of dermatitis in vaccinated pigs. There was a significant difference (P < 0.05) in the mortality of pigs in the unvaccinated group and the 2-dosed vaccinated group. PCV2 viremia was detected in the blood and peaked at 105 days old in both unvaccinated pigs (Ct-adj = 8.40) and pigs vaccinated with 1 dose (Ct-adj = 6.37), while no detectable PCV2 virus was found in the blood of pigs vaccinated with 2 doses. At 77 and 105 days old, the PCV2 viremia load (Ct-adj) of unvaccinated pigs and those vaccinated with 1 dose was significantly higher (P < 0.05) than that of the 2-dosed vaccinated pigs. The body weight (BW), average weight gain (AWG), and average daily gain (ADG) in both groups of vaccinated pigs were significantly higher (P < 0.05) than those of unvaccinated pigs. The study vaccine was significantly efficacious in protecting vaccinated pigs against clinical symptoms, blood viral load, and mortality, as well as improving productivity, compared with unvaccinated pigs.     

Ethanol-soluble components in soybean meal influence the digestive physiology,hepatic and intestinal morphologies,and growth performance of the marine fish pompano (Trachinotus blochii)

This study aimed to examine the effects of ethanol-soluble components (Es) in soybean meal (SBM) on gut content transit, bile acid (BA) and pancreatic digestive enzyme secretions, nutrient apparent digestibility coefficients (ADC), liver and intestinal morphologies, and growth performance of pompano (Trachinotus blochii). The SBM was extracted with aqueous ethanol, then the supernatant and residue were separated and dried to produce ethanol-extracted SBM (ESBM) and the Es. Four experimental diets were formulated with fish meal (FM), ESBM and SBM as main dietary protein sources. The diets were denoted as follows: FMD (FM diet), SBMD (SBM diet), ESBMD (ESBM diet) and ESBM + EsD (ESBM plus Es diet). Thirty-five fingerling pompano with an initial body weight (BW) of 18.3 g were allocated to each of 12 polyvinyl chloride tanks (1000-L holding capacity), resulting in triplicate tanks per dietary treatment. For 10 weeks, the fish were hand-fed the experimental diets to apparent satiation twice daily. The results showed that the final BW, weight gain and specific growth rate were significantly lower, while the feed conversion ratio was higher in the SBMD and ESBM + EsD groups than in the ESBMD and FMD groups (p < 0.05). Fish fed SBMD and ESBM + EsD showed accelerated gastric transit, slowed intestinal mobility, and lowered secretions of BAs and pancreatic digestive enzymes as compared to those fed ESBMD and FMD. Morphological abnormalities in mucosal folds of the posterior intestine, but not the liver, were clearly observed in the SBMD and ESBM + EsD groups. These results indicated that the Es in SBM inhibited the digestive system, leading to decreased nutrient digestibility and growth performance in pompano. The findings of the present study suggested that removal of the Es would effectively improve the nutritional quality of SBM and enhance growth performance of pompano fed a SBM-based diet.     

Evaluation of non-linear growth curve models in the Vietnamese indigenous Mia chicken

Understanding of animal growth is important for the improvement of management and feeding practices; however, little is known about the growth curve in Vietnamese indigenous chicken. This study was performed to determine the most appropriate models for describing the growth curve of Vietnamese Mia chicken. The study evaluated the performances of the Logistic, Gompertz, Richards, and Bridges models of body weights in 224 Mia chickens. Models were fitted using minpack.lm package in R software and Akaike’s information criterion and Bayesian information criterion were used for model comparison. Based on these criteria, the Gompertz and Bridges were the best models for males and females, respectively. Estimated asymmetric weights (α) were ranged from 2,241.91 ± 14.74 (g) (Logistic) to 2,623.86 ± 30.23 (g) (Gompertz) for males and from 1,537.36 ± 10.97 (g) (Logistic) and 1,958.36 ± 72.92 (g) (Bridges) for females, respectively. The age at the inflection point was estimated from 9.32 to 10.5 weeks and from 8.51 to 9.86 weeks for males and females, respectively. In conclusion, the Gompertz model is the most suitable model for describing the growth curve of Mia chicken. The parameters obtained from growth models could help define feeding programs to meet nutritional needs from hatching to the age of maximum growth, reproduction programs, and marketing strategies.     

Transgenic wheats with elevated levels of Dx5 and/or Dy10 high-molecular-weight glutenin subunits yield doughs with increased mixing strength and tolerance

To test the effects of independently increasing the in vivo levels of high-molecular-weight glutenin subunits (HMW-GS) Dx5 and Dy10 on wheat flour properties, we increased the copy numbers of their corresponding genes by genetic transformation. Thirteen transformants with increases in one or both subunits were chosen for biochemical and functional characterization by solvent fractionation, RP-HPLC, SDS-sedimentation, and micro-mixing. Increases in Dx5 and Dy10 contents ranged from 1.4- to 3.5-fold and 1.2- to 5.4-fold, respectively, and generally resulted in increased polymeric protein, increased mixing times and tolerances, and lower peak resistances. Increases in Dx5 content had larger effects on most parameters than comparable increases in Dy10. Flours with more than 2.6-times the native levels of Dx5 could not be mixed under standard 2-g mixograph conditions, while flours with 5.4 times the native levels of Dy10 could be mixed if sufficient time was allowed. Increases in Dx5 and Dy10 had additive effects on mixing behavior. These experiments demonstrate that dough mixing strength and tolerance can be increased by raising the levels of native HMW-GS Dx5 or Dy10, but that the effects of the two subunits are quantitatively and qualitatively different.