Utilization of Frozen Semen of Wild Yak

After domestication of wild yak and utilization of its frozen semen was successful in 1983, frozen semen of wild yak was used to improve domestic yak and local yellow cattle by artificial insemination(AI). Hybrid vigor of their F1 was obvious, i. e. , productive performance of F1 was significantly increased. Their offspring did not only have significant heterosis in performance but also can rejuvenate effectively their adaptability and survival, and can use alpine grassland more efficiently. This resulted in significant social and economic benefits.Compared with dairy cattle, beef cattle and yellow cattle, AI of yak was more difficult. Using AI to improve yak performance was difficult and significant in yak production areas of our country. It is necessary to invest more technique and fund to extend AI.     

Isolation and Identification of One Strain of Pigeon Paramyxovirus SerotypeⅠ

A pigeon paramyxovirus serotypeⅠ(PPMV-1) isolate was recovered from samples collected from dead pigeons and initial isolation of the virus was performed in 9-day-old specific-pathogen-free (SPF) chicken embryos.The isolate was identified by the hemagglutination (HA) test,hemagglutination-inhibition (HI) assays,RT-PCR,sequencing and analysis of partial of F gene of the virus.The virulence and pathogenicity of the isolate were determined by mean death time (MDT),intracerebral pathogenicity index (ICPI) in 1-day-old chicks and animal regression experiment.The results indicated that one PPMV-1 was isolated from dead pigeon and named as GXP120012.The F gene sequence analysis of PPMV-1 GXP120012 strain showed that the cleavage sites of the virus was ¹¹²R-R-Q-K-R-F¹¹⁷ motif in accordance with characteristic of velogenic strains;The nucleotide sequence homologies of F gene between strain GXP120012 and PPMV-1 reference strain pi/CH/LLN/110713 were high and reached 98.9%.They located the same branch on phylogenetic tree and fell into genotype Ⅵ.The MDT and ICPI values of isolate were 102 h and 0,respectively.The results of animal regression experiment showed that GXP120012 isolate was virulent for pigeons and avirulent for chickens.The present study provided useful material and theoretical basis for the study of molecular epidemiology and prevention and control of Newcastle disease in pigeon in future.     

The microstructure of the cuticle‐less shell of the eggs of the domestic hen

1. Open pores were a notable feature of the shell of hens' eggs which were naturally devoid of cuticle.

2. In contrast with normal eggs, the surface of the cuticle‐less shell was irregularly contoured and, in many instances, deeply fissured.     

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.     

Effect of Different Ratios of Food to Water of Dry Powder Feed on Growth Performance，Nutrient Digestibility and Nitrogen Metabolism of Growing Wusuli Raccoon Dogs

This experiment was aimed to explore the effect of different ratios of food to water of dry powder feed on growth performance,nutrient digestibility and nitrogen metabolism of growing Wusuli raccoon dogs.Thirty 11-week-old healthy Wusuli raccoon dogs with average body weight of （3.47±0.20） kg were randomly assigned into 3 groups.The Wusuli raccoon dogs were fed experimental diets with dry powder feed of ratio of food to water of 1∶2.5 （group Ⅰ）,1∶3.5（group Ⅱ）,1∶4.5 （group Ⅲ）,respectively.The pre-test period lasted for 7 days and the trial period lasted for 67 days.The results showed that the average daily feed intake of each week from 11,12 to 13 weeks in groupⅠ was significantly less than that in groups Ⅱ and Ⅲ （P＜0.05）,the average daily feed intake of each week from 14,15 to 20 weeks was no significant difference among all groups （P＞0.05）.The total intake in group Ⅰ was significantly less than that in group Ⅱ （P＜0.05）.The average daily gain of each week from 15 to 17 weeks in group Ⅲ was significantly higher than that in group Ⅰ （P＜0.05）,while the average daily gain,total weight and the rate of feed intake to body gain in other week-old were no significant differences among all groups （P＞0.05）.The protein digestibility,fat digestibility and dry matter digestibility were no significant differences among all groups （P＞0.05）.The amount of urine in group Ⅲ was extremely significantly higher than that in groups Ⅰ and Ⅱ （P＜0.01）.The nitrogen intake,fecal nitrogen,urine nitrogen,nitrogen deposition,net protein utilization and biological value of protein were no significant differences among all groups （P＞0.05）.In conclusion,the appropriate ratios of food to water of dry powder feed of growing Wusuli raccoon dogs was 1∶3.5 to 1∶4.5.     

Effect of Supplement of Lysine on the Nutrients Arriving at the Abomasum of Polled Dorset譙mall-tail Han Lambs

将8只40日龄安装永久性皱胃瘘管的无角陶赛特与小尾寒羊杂交F1代母羔(平均体重为8.90 kg±0.38 kg)根据体重分为2组,每组4只,在60~80、81~120和121~240日龄分别饲喂日粮1、2和3,并分别添喂1.2%、0.8%和0.4%的赖氨酸,以研究添喂赖氨酸对到达羔羊皱胃营养物质的影响。结果表明,与对照组相比,在日粮1、2和3中添喂不同水平的赖氨酸,使羔羊到达皱胃的干物质分别增加了7.01%(P＞0.05)、11.59%(P＜0.01)和10.65%(P＜0.05),有机物分别增加了8.48%(P＞0.05)、13.01%(P＜0.05)和12.14%(P＜0.01),粗蛋白质分别增加了11.12%(P＞0.05)、21.73%(P＜0.01)和12.44%(P＜0.05),微生物蛋白分别增加了13.46%(P＜0.05)、26.85%(P＜0.01)和15.08%(P＜0.05),总氨基酸分别增加了39.22%(P＜0.01)、35.52%(P＜0.01)和28.27%(P＜0.05),总必需氨基酸分别增加了49.21%(P＜0.01)、34.40%(P＜0.01)和28.11%(P＜0.05),赖氨酸分别增加43.77%(P＜0.01)、37.25%(P＜0.01)和34.38%(P＜0.05)。在对照组和试验组中,到达皱胃的赖氨酸主要为结合赖氨酸,而游离赖氨酸一般低于总赖氨酸量的1%。添喂赖氨酸使羔羊的干物质自由采食量分别比对照组提高了12.57%(P＞0.05)、19.38%(P＜0.01)和16.29%(P＜0.01),前胃干物质消化量分别增加了20.81%(P＞0.05)、35.64%(P＜0.01)和19.97%(P＜0.01),日增重分别提高了17.34%(P＜0.05)、21.30 %(P＜0.01)和17.76%(P＜0.05)。因此,给60~240日龄羔羊添喂赖氨酸可增加到达皱胃的营养物质的量和前胃有机物的消化量,从而增加羔羊的营养供应。     

Growth and Development of The Kunlun Type of Wild Yak

The observation of body height and weight of 10 captured wild yak shows the body height and weight of the wild yak at three and four months old were similar with that of domestic yak. At their 24 months old, the body height and weight were higher by 26.9 % and 62.5 % than that of the domestic ones. The results indicate that, once adapted to the half-shed and half-grazing conditions, the tamed Kunlun type of wild yak with superior genetics would grow and develop faster than the domestic yak at elder ages.     

Comprehensive Analysis of Mixed Soda Saline-Alkali Resistance of Germplasm Resources of Longmu Alfalfa北大核心CSCD

The effects of mixed soda saline-alkali (NaHCO3:Na2CO3=9:1) at different concentrations (10,20,30,40 and 50 mmol·L-1) on the germination of five Longmu alfalfa seeds were studied. The results showed that the germination rate,germination potential,germination index,vigor index,dry weight,fresh weight,water content,embryo length,radicle length of alfalfa seeds showed different trends under different mixed soda saline-alkali concentrations. Through principal component analysis of nine indicators,GR,GP,GI,VI,FW,WC and EL indicators were screened out to be related to salt and alkali tolerance of Longmu alfalfa varieties. According to the analysis of membership function,weight coefficient and D value of comprehensive evaluation,the salt and alkali tolerance of five longmu alfalfa varieties were in the order of LM 807 > LM 808 > LM 806 > LM 803 > LM 801. © 2019 Ｊｏｕｒｎａｌ ｏｆ Ｒｅｆｒｉｇｅｒａｔｉｏｎ. All rights reserved.     

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.     

Is breed-specific legislation justified? Study of the results of the temperament test of Lower Saxony

Beginning in July 2000 legislation in Lower Saxony restricted the keeping of bull terriers, American Staffordshire terriers, pit bull terriers, and 11 other breeds. Exemption was possible after attending an especially developed test. The tests analyzed for breed predisposition for excessively aggressive signaling or aggressive behavior in inappropriate situations, differences in behavior between breeds, and factors differentiating biting from nonbiting dogs.The test results of 415 dogs were analyzed. The test consisted of a veterinary examination; a learning test; situations of dog-human, dog-environment, and dog-dog contact; and obedience. Escalation in aggressive behavior was scored using a scale of 1-7. No aggressive behavior (1 on the scale) was shown by 38.07% of the dogs, 61.69% showed aggressive behavior scored as 2 to 5 on the scale, and 0.24% bit without previous threatening signals (6 on the scale).Concerning a score of 1 on the scale, pairwise comparison (chi-square test) showed significant differences between bull terriers and American Staffordshire terriers (P = 0.004), pit bull terriers (P = 0.01), Doberman pinschers (P = 0.003), and rottweilers (P = 0.009). Concerning scores of 2 to 7 on the scale,, no significant differences were found.Ninety-five percent of the animals reacted appropriately in the test situation. Five percent displayed excessive aggressive signaling or aggressive behavior in inappropriate situations. These displays were associated with unusual movements and the dogs' apparent apprehension. Correlation between test results and owners jerking on the leash or misinterpreting their dogs' behavior and dogs trying to elude physical manipulation was found. No significant difference in behavior between breeds was detected.The results show no indication of dangerousness in specific breeds. Justification for specific breed lists in the legislation was not shown.     

Effect of Discontinuous Administration of β -glucan and Glycyrrhizin on the Growth and Immunity of Pacific White Shrimp Litopenaeus Vannamei

A six-week growth trial was conducted to compare the effects of different feeding strate- gies of dietary immunostimulants on the growth and immunity of white shrimp Litopenaeus vannamei （4.70 ±0.20g）. Shrimps were fed with diet containing glycyrrhizin continuously, containing β -glucan continuously, discontinuously （seven days with diet containing β -gluseven days with diet without -glucan; two days with diet containing β-glucan following five days with diet without -glucan）,     

What kind of formation in the multiethnic culture of the European Union of the third millennium?

Even though occidental food production and control systems guarantee a reasonable level of safety for consumers, western countries are facing a growing phenomenon of immigration from all over the world. With this enrichment and the shuffling of cultures and customs in the same places, even alimentary habits undergo an unavoidable evolution, also influencing the commercial trends of society. The growing demand for ethnic products, often of uncertain provenance, composition and manufacturing, has motivated the appearance of illegal trade and markets or improper local productions besides the legal ones, implying a rise in hygienic risks for the consumers. These underground realities, together with the unfilled gap that still exists between different cultures and customs cause significant difficulties in carrying out efficient controls to guarantee sanitary safety for consumers. For this reason, the risks associated with this increasing globalization must be faced with proper information and a decisive formative strategy must be divided, in order to allow the operator of the whole system and control employees to be acquainted about different raw materials, manufacturing systems, alimentary habits, languages for communication and commercial dynamics which stand beyond the new alimentary trends.     

Chronic non-progressive pneumonia of sheep in New Zealand – a review of the role of Mycoplasma ovipneumoniae

Chronic non-progressive pneumonia (CNP) is a common disease which affects lambs in New Zealand during late summer and autumn. Mycoplasma ovipneumoniae can be recovered from a high proportion of lesions but it is also present in some normal lungs. Bacteria, especially Pasteurella haemolytica, can also be recovered from more than half the lungs of affected animals.

Isolates of M. ovipneumoniae are genetically heterogeneous, as demonstrated by examination of their DNA or total cellular proteins, and are serologically heterogeneous as shown by metabolic inhibition tests. The number of strains present in New Zealand is large and several distinguishable strains can be recovered from each affected lung. Mycoplasma ovipneumoniae has pathogenic potential as indicated by its ability to produce hydrogen peroxide, cause ciliostasis and by its possession of a capsule.

Chronic non-progressive pneumonia can be transmitted consistently to over 50% of lambs by inoculation of pooled pneumonic lung homogenate and transmission can be suppressed by broad spectrum antibiotics. In contrast, penicillin does not prevent the development of lesions but diminishes their severity. Pooled lung homogenate treated with digitonin, which inactivates mycoplasmas, has failed to transmit CNP. Pure cultures of M. ovipneumoniae produce only mild lesions in some animals, whereas inoculation with pooled lung homogenate (from which no viruses were isolated) containing mixed strains of M. ovipneumoniae and free from bacteria, is more effective in producing lesions.

Research work to date suggests that CNP may be initiated by colonisation of the lung by M. ovipneumoniae which causes ciliostasis and elicits an exudate allowing colonisation of the lungs by bacteria especially P. haemolytica and by other strains of M. ovipneumoniae. The immune response to the initial strain of M. ovipneumoniae may inhibit its replication but would be less effective in inhibiting heterologous strains of the organism allowing their sequential replication. Eventually production of a broad immune response to M. ovipneumoniae would lead to its elimination which in turn would facilitate the elimination of other microorganisms and the resolution of lesions. As natural immunity to CNP occurs within the first year, it may be possible to develop an effective and useful vaccine. Such a vaccine may need to include multiple strains of M. ovipneumoniae.     

Evaluation of Virulence and Immune Effect of a Duck Paramyxovirus Type Ⅰ Strain

In this study,the biological and genetic characterization of a paramyxovirus type Ⅰ strain (GSFY strain) which was obtained from Muscovy duck were determined. Afterward,GSFY strain was developed as an inactivated oil emulsion vaccine. The protective evaluation of this new vaccine candidate was conducted on the Muscovy duck. The results showed that the mean death time (MDT) of chicken embryo,the intracerebral pathogenicity index (ICPI) of 1-day-old chicken and the intravenous pathogenicity index (IVPI) in 6-week-old chicken were 71 h,1.75 and 2.49, respectively. Homologous comparison of F gene nucleotide sequence showed that the GSFY strain shared 97.1% with Chicken/China/Guangxi 9/2003,which was the highest homology,and they all belonged to type Ⅶ. The results suggested that this newly isolated strain was the type Ⅶ high virulent paramyxovirus. The immunize protective evaluation results suggested that the mean antibody titer of 7 and 21 days after the third immunization were 6log2 and 8log2,respectively. When the immunized duck were attacked with GSFY strain,100% protective rate could be expected when the mean antibody titer was above 5log2. This study provided the basic data for vaccine development of avian type Ⅰ paramyxovirus.     

Characteristics of Nutrient Contents and Evaluation of Nutritional Value of the Alpine Grassland Plants in the Source Area of the Yellow River北大核心CSCD

In order to explore the characteristics of nutrient contents and scientifically evaluate the nutritional value of the alpine grassland plants in the source area of the Yellow River, the plants of the five different alpine grasslands were selected as the research objects, and the content of crude protein (CP), ether extract (EE), crude fiber (CF), crude ash (CA), total phosphorus (TP) of the plants were determined. At the same time, the principal component analysis method was used for quantitative comprehensive evaluation of the plants nutritional value. The results showed that the CP content of the plants in all alpine grasslands was between 12.78%~15.35%, the EE content was between 2.63%~3.38%, the CF content was between 17.56%~25.16%, the CA content was between 5.52%~11.53% and the TP content was between 0.11%~0.27%. The order of nutrient value of plants in different alpine grassland from high to low was: degraded alpine meadow > native alpine meadow > swamp meadow > degraded alpine steppe> native alpine steppe;The order of yield per unit area of the total nutrients of plants in different alpine grasslands from high to low was: swamp meadow > native alpine meadow > native alpine steppe> degraded alpine steppe> degraded alpine meadow;The order of nutrient value of different plant species from high to low was: Leguminosae>Forbs >Cyperaceae>Gramineae. © 2019 Authors. All rights reserved.     

Study on Intensity of Tissue Respiratory Metabolism in The Calves of Domestic Tak and Filial-generation of Wild Yak

The ITRM of liver, one of the important indexes of tissue respiratory metabolism in yak, is higher than other tissues. The relationship of ITRM and time belongs to the equation y = aebt. The ITRM of each tissue in reciprocal yaks were significant(P＜0.05) lower than that of the domestic yaks which showed that the adaptability to hypoxia of the reciprocal yaks were more powerful than the domestic yaks.