Study on The Isozyme of Wild Yak

We have adopted PAGE method to isolate lactic dehydrogenase(LDH)and α-amylase(α-Am)from wild yak's serum and measure the physical-chemical properties of the two components respectively. The results showed that the yak LDH isozyme distributed into five bands. The sequence according to their activity reads as LDH1 ＞ LDH2＞ LDH3 ＞ LDH4 ＞ LDH5. The subunit B is relatively occupied a dominant position. It got a wide operating pH range, high thermal stability,well denature resistance and a fairly large adaptability threshold on the physical-chemical change of surrounding environment. α-Am isozyme distributed into seven bands and also got a wide operating pH range. α-Am isozyme is high sensitivity to environmental temperature.     

Absence of effects of dietary α‐tocopherol on egg yolk pigmentation

1. Three experiments were carried out in which yolk colour and carotenoid content were measured in hens fed diets containing soyabean oil or tallow and supplemented with 0, 10, 20, 40, 80, 160 or 320 mg tocopheryl acetate.

2. Fat type had no consistent effect on yolk carotenoid content but yolk α‐tocopherol concentrations were lower with the soyabean oil diet.

3. Yolk concentrations of all carotenoids measured and yolk colour were unaffected by dietary α‐tocopherol concentration.     

Effect of beta‐aminoproprionitrile on eggshell formation

1. Eggshells are bioceramic‐biopolymer composites made by a cell‐mediated deposition of an extracellular matrix which drives the organisation of the inorganic phase. Ultrastructurally, eggshells are composed of shell membranes, mammillary knobs, palisade, and cuticle. Shell membranes are two nets of type X collagen‐containing fibrils. On to these membranes, the mammillary knobs, that is, the crystal nucleation sites, are deposited. Type X collagen is highly cross‐linked and insoluble.

2. In order to evaluate the role of type X collagen cross‐linking on eggshell formation, hens were injected with different doses of β‐aminoproprionitrile, which specifically interferes with cross‐link formation.

3. Changes in egg size and shape were observed. Scanning electron micrographs analysis of these eggs demonstrated marked changes in crystal growth and shell membrane structure and arrangement. A dot‐blot analysis, using a monoclonal antibody against chicken type X collagen, shows a dose‐dependent increase in shell membrane collagen extractability.

4. It is concluded that the formation of β‐aminoproprionitrile‐sensitive cross‐links among the type X collagen molecules of the shell membranes play an essential role in normal eggshell formation.     

Effects of avgard™ treatment on the microbiological flora of poultry carcases

1. The efficiency of the AvGard? (or Assur‐Rince? in the USA) trisodium phosphate poultry carcase decontamination process was evaluated during both manual and industrial trials against total aerobic mesophilic count (TAMC), thermotolerant coliforms, Pseudomonas, Enterobacteriaceae, Campylobacter, Listeria monocytogenes and Salmonella.

2. The TSP treatment proved to have significant effects on the bacterial decontamination of poultry neck skin, lowering the contamination by a factor of about 10 for TAMC and of 100 for Coliform and Pseudomonas.

3. Numeration of Salmonella with an innovative miniaturised most probable number method has proved that the effect upon these micro‐organisms was also close to 2 log₁₀ reduction.

4. The effect of TSP treatment on the ecological balance of psychrotrophic bacterial flora was also investigated to study the origin of the shelf‐life flora of treated carcases (Pseudomonas being reduced to the limit of detection) and to ascertain whether L. monocytogenes might gain a competitive advantage. In fact AvGard? reduced the number of L. monocytogenes on poultry carcases.

5. As a consequence of the virtual elimination of the Pseudomonas usually present, Brochothrix thermosphacta became the main species responsible for putrefaction.

6. Because the growth rate of Brochothrix thermosphacta was greater than that of L. monocytogenes at refrigeration temperature, it was considered that putrefaction would occur before the emergence of large numbers of L. monocytogenes.     

Elevation of shoot‐apices of two ecotypes of Themeda triandra on the Transvaal Highveld

In a series of investigations from 1965 to 1970 on the Transvaal Highveld it was found that trie elevation of shoot apices of two ecotypes of Themeda triandra was affected by season, ecotype and treatment. The absence of defoliation increased the susceptibility of the ecotypes to defoliation, whereas the shorter the defoliation the greater the subsequent resistance to grazing. The most important finding was that general application of earlier research findings from Natal was not possible in this case.     

Analysis of High Reproductivity on Wild Yak Bull

Sperm concentration of wild yak bull is 2. 13 billion per milliliter. Survival time at 0-4 ℃ is 57hrs. After thawing survival time at 37 ℃ is 12 hrs. Resistance coefficient is 144,000. Abnormal sperm rate and acrosomal integrated rate of post-thawing is 9.17% and 87.53% respectively. Moving viscosity is 1. 169 cp. Total nitrogen is 1 437.7 mg/100 ml. Head of sperm is significantly shorter and end piece is significantly longer than that of domestic yak and yellow cattle. Activity of hyaluronidase is highly stronger than the domestic yak,and the activity of LDH is higher than the domestic yak by 48 %. Hence,the fertility of the wild yak bull is powerful and the artificial inseminated rate with domestic yak and yellow cattle is 88.9% and 71.58% respectively.     

The effect on herd production of “free” electricity on a milking plant

Extract

Prior to the 1956–7 season, the herd investigated had a steadily rising curve of production. This levelled out at approximately 350 lb butterfat average production per cow, and was maintained for two further seasons.     

Influence of β ‐glucanase on feeding value of barley for poultry and moisture content of excreta

1. The cause of the sticky droppings and poor performance that can occur when barley is fed to poultry was investigated.

2. The problems could be overcome by water‐treatment of the barley or by addition of β‐glucanase.

3. The problems appear to be caused by a viscous factor, which is hydrolysed by β‐glucanase. Water‐treatment allows hydrolysis by enzymes in the barley.

4. Heat‐treatment of barley denatures hydrolytic enzymes and prevents reduction in viscosity.     

Assessment of test–retest reliability of animal-based measures on growing pig farms

Measures taken on animals are subject to variations and their reliability may represent one of their main limitations when used in a welfare assessment tool. Test–retest reliability refers to the likelihood that the same results will be obtained if the assessment is repeated by the same observer. This study discusses the test–retest reliability of quantitative and qualitative animal-based measures included into the Welfare Quality^® protocol on a sample of 15 intensive conventional farms of growing pigs. An average of 12 months elapsed between the two visits and no changes in management routines or housing conditions were made by the farmers during this interval. A Wilcoxon signed rank test was used to test whether the mean results obtained during the two visits were significantly different. Different methods were used to assess repeatability of mean prevalences at farm level: Spearman's correlation coefficient (rs), intra class correlation coefficient (ICC) and limits of agreement (LoA). Moderate bursitis, widespread skin discolouration and positive social behaviour presented mean results significantly different between the two visits (P<0.05). From a discriminative point of view, only moderately soiled body (rs=0.7; ICC=0.8) and the panic response (rs=0.7; ICC=0.5) were consistent the 12 month period. However, inconsistencies between Spearman's correlation and ICC were found when interpreting the reliability of several quantitative measures such as severely wounded animal and severely soiled body. The Qualitative Behaviour Assessment (QBA) was subject to a significant effect of visit, however, the two sets of scores were moderately related on the first axis of the principal component analysis (rs=0.5). A more evaluative approach such as the limits of agreement can be useful to guide the interpretation of test–retest reliability of quantitative measures based on farm averages and to detect farms that present a persistent welfare problem. Unless the assessment relates only to the relative ranking of a farm within the same visit, the QBA is not consistent over the 12 month period.     

Effects of Melatonin on Gastrointestinal Tract Physiological Function of Ruminant北大核心CSCD

褪黑素(MT)是调节胃肠道运动、免疫功能及微生物菌群结构等的胺类激素,其前体物质(色氨酸)是微生物群-肠-脑轴的信号递质。目前有关MT的研究多集中于单胃动物,鲜见MT对反刍动物的综述报道。因此,本综述将从MT对反刍动物胃肠运动、摄食行为、生产性能以及胃肠道微生物的作用机制进行阐述,以期为MT作为反刍动物治疗辅助剂、饲料添加剂的价值提供参考。     

Effects of β-alanine on intestinal development and immune performance of weaned piglets

Beta-alanine is an important amino acid involved in several metabolic reactions in the body. The study aimed to investigate the effect of β-alanine supplementation on intestinal development and the immune performance of weaned piglets. Thirty-two 21-day-old healthy weaned piglets(half female and half male; Duroc × Landrace × Yorkshire) with an initial body weight of 8.11 ± 0.21 kg were randomly divided into 4 groups with 8 replicates of 1 pig each. The control group was fed a basal diet and the ...     

Evaluation of Therapeutic Effect of Porcine β-defensin-2 on Streptococcus suis Infection

Defensin is a small cationic peptide widely distributed in animals and plants. It is an important component of the innate immune defense system of mammals. It has a broad spectrum of antibacterial, antiviral and antifungal activities. Porcine β-defensin-2 (PBD-2) is one of the natural defensins expressed in pigs and has good antibacterial activity in vitro. The purpose of this study is to evaluate the therapeutic effect of PBD-2 in the treatment of Streptococcus suis infection in animals and to provide more insights for evaluating the value of PBD-2 as a therapeutic drug. Firstly, the bactericidal activity of PBD-2 against S. suis clinical isolate SC-19 was measured in vitro, and the cytotoxicity of PBD-2 was tested on mouse-derived macrophages (RAW264.7). Subsequently, C57 female mice aged 4-6 weeks and weighing between 18-22 g infected with S. suis SC-19 were treated with PBD-2 or PBS (n ≥ 6). The survival rate of mice, and the bacteria loads, inflammatory cytokine levels, and pathological changes of tissues were determined. The results showed that PBD-2 (25-200 μg·mL^-1) could significantly inhibit the growth of S. suis SC-19 in a concentration-dependent manner (P<0.05). At the same time, PBD-2 had no significant toxic effect on RAW cells (P>0.05). The in vivo study revealed that PBD-2 treatment could effectively reduce the mortality of mice infected with S. suis SC-19. At the same time, PBD-2 treatment significantly reduced bacteria loads in brain, lung, spleen and blood of mice, and decreased the levels of inflammatory cytokines IL-6, IL-12 and TNF-α in mouse sera (P<0.05). At the same time, PBD-2 treatment also significantly alleviated the degree of pathological damages in lung and spleen tissues of mice infected with bacteria (P<0.05). These results indicate that PBD-2 confers great resilience to S. suis in vitro without significant cytotoxicity, while it also exhibits a therapeutic effect on S. suis infection in mice, suggesting that the use of PBD-2 as a therapeutic drug and substitutes for antibiotics is of an excellent prospect.     

Does meatiness of pigs depend on the level of gastro-intestinal parasites infection?

The aim of the present paper was to determine an influence of the presence and a level of intestine parasites infection on the quality of pork carcass expressed by the content of meat in carcass (meatiness) in pigs. The experimental part of the study was conducted on pigs farm produced in a closed cycle. The population in the study included 120 fattening pigs maintained in two keeping systems: group I--60 individuals kept on slatted floor, and group II--60 individuals kept on deep litter. All the experimental animals were treated in the same manner. The analysed fatteners were slaughtered in Meat Processing Plant when their body mass reached 110 kg, and the post-slaughter assessment was conducted according to the EUROP classification of pigs carcass using the Ultra-Fom 300 device. The study concerning the internal parasites were conducted basing on coproscopic quantitative McMaster method. As a results, the eggs of three nematode taxa were isolated and identified: Oesophagostomum spp., Ascaris suum and Strongyloides ransomi. Overall prevalence of infection of fatteners kept on litter was lower (25%±11.2) as compared to those kept on slatted floor (38.3%±12.6), however the differences were not statistically significant (χ(2)=2.465; df=1; P=0.116). The mean value of meatiness for pigs free from parasites was 53.68, while in the case of infected pigs the meatiness was statistically lower and was 52.12 (t=2.35; P=0.02). The analysed pigs were classified into three categories and conducted analysis of an influence of parasites on meatiness demonstrate the relationship that is statistically significant. The analysis of correlation between meatiness and an average number of helminth eggs also demonstrated the negative, statistically significant, relationship (F=5.52; P=0.020), i.e. in fatteners with higher EPG value the meatiness was lower.     

Antiproliferative effect of α-mangostin on canine osteosarcoma cells

Osteosarcoma is the most frequently diagnosed primary bone tumor in dog. Since chemotherapeutics are quite limited due to high cost and severe toxicity, therefore, the ultimate goal is to discover cost-effective therapeutics with less toxicity. We have studied the effect of α-mangostin, a xanthone derivative isolated from pericarp of mangosteen (Garcinia mangostana Linn.) in canine osteosarcoma, D-17 cells. The results showed that α-mangostin induced antiproliferation with IC(50) at 15 μg/ml. Hoechst 33342 nuclear staining and nucleosomal DNA-gel electrophoresis revealed that α-mangostin could induce nuclear condensation and fragmentation, typically seen in apoptosis. Cell cycle analysis demonstrated that α-mangostin induced sub-G1 peak. In addition, α-mangostin also induced membrane flipping of the phosphatidylserine and the loss of mitochondrial membrane potential in D-17 cells. In conclusion, α-mangostin, induced apoptotic cell death against canine osteosarcoma D-17 cells, could be a potential candidate for preventive and therapeutic application for bone cancer treatment in dogs.