Sequential histopathologic changes of type I, pre-type II and type II ostertagiasis in cattle

Yearling cattle in Louisiana were examined at monthly intervals for abomasal nematode burdens and histological lesions over a year. Tracer calves were grazed for 3 to 4 weeks and removed from pasture for 2 to 3 weeks, then slaughtered; a few animals were killed in extremis shortly after removal from pasture. Histological changes were correlated with worm burdens and characterized according to the type of Ostertagia ostertagi infection present. In cattle with acute Type I ostertagiasis, changes varied from eosinophil infiltration to glandular dilation and slight mucous cell hyperplasia with submucosal edema. During the summer months the cattle had worm burdens that were primarily early 4th stage larvae (EL4), with changes characterized by minimal glandular dilation and mucous cell metaplasia and moderate lymphoid cell proliferation and with intramucosal migration of EL4. In the autumn, the maturation of EL4 produced the Type II syndrome with severe glandular changes, prominent mucosal hyperplasia and marked lymphoid cell accumulation. With increased duration of the pre-Type II interval, there was greater development of the subepithelial lymphoid tissue and increased frequency of epithelial globule leukocytes. The lymphoproliferation which occurred during the prolonged pre-Type II interval appeared to be related to the increased severity and mortality seen with the Type II ostertagiasis syndrome.     

Comparison of type I and type II bovine viral diarrhea virus infection in swine.

Some isolates of type II bovine viral diarrhea virus (BVDV) are capable of causing severe clinical disease in cattle. Bovine viral diarrhea virus infection has been reported in pigs, but the ability of these more virulent isolates of type II BVDV to induce severe clinical disease in pigs is unknown. It was our objective to compare clinical, virologic, and pathologic findings between type I and type II BVDV infection in pigs. Noninfected control and BVDV-infected 2-month-old pigs were used. A noncytopathic type I and a noncytopathic type II BVDV isolate were chosen for evaluation in feeder age swine based upon preliminary in vitro and in vivo experiments. A dose titration study was performed using 4 groups of 4 pigs for each viral isolate. The groups were inoculated intranasally with either sham (control), 10(3), 10(5), or 10(7) TCID50 of virus. The pigs were examined daily and clinical findings were recorded. Antemortem and postmortem samples were collected for virus isolation. Neither the type I nor type II BVDV isolates resulted in clinical signs of disease in pigs. Bovine viral diarrhea virus was isolated from antemortem and postmortem samples from groups of pigs receiving the 10(5) and the 10(7) TCID50 dose of the type I BVDV isolate. In contrast, BVDV was only isolated from postmortem samples in the group of pigs receiving the 10(7) TCID50 dose of the type II BVDV isolate. Type I BVDV was able to establish infection in pigs at lower doses by intranasal instillation than type II BVDV. Infection of pigs with a type II isolate of BVDV known to cause severe disease in calves did not result in clinically apparent disease in pigs.     

生产计件工资新模式探索

随着《新劳动合同法》的实施，人力资源成本逐步上升，劳动用工风险随之放大。南方希望饲料企业传统的生产作息时间存在着一定的劳务纠纷隐患，本着以人为本，和谐劳资关系为目的，南方希望开始做好生产计件员工工时管理，调整传统计酬方式，并在分子公司进行试点，取得一定成效，现将此模式与大，家分享，希望大家批评指正。     

Niacin supplementation induces type II to type I muscle fiber transition in skeletal muscle of sheep

Background

It was recently shown that niacin supplementation counteracts the obesity-induced muscle fiber transition from oxidative type I to glycolytic type II and increases the number of type I fibers in skeletal muscle of obese Zucker rats. These effects were likely mediated by the induction of key regulators of fiber transition, PPARδ (encoded by PPARD), PGC-1α (encoded by PPARGC1A) and PGC-1β (encoded by PPARGC1B), leading to type II to type I fiber transition and upregulation of genes involved in oxidative metabolism. The aim of the present study was to investigate whether niacin administration also influences fiber distribution and the metabolic phenotype of different muscles [M. longissimus dorsi (LD), M. semimembranosus (SM), M. semitendinosus (ST)] in sheep as a model for ruminants. For this purpose, 16 male, 11 wk old Rhoen sheep were randomly allocated to two groups of 8 sheep each administered either no (control group) or 1 g niacin per day (niacin group) for 4 wk.

Results

After 4 wk, the percentage number of type I fibers in LD, SM and ST muscles was greater in the niacin group, whereas the percentage number of type II fibers was less in niacin group than in the control group (P < 0.05). The mRNA levels of PPARGC1A, PPARGC1B, and PPARD and the relative mRNA levels of genes involved in mitochondrial fatty acid uptake (CPT1B, SLC25A20), tricarboxylic acid cycle (SDHA), mitochondrial respiratory chain (COX5A, COX6A1), and angiogenesis (VEGFA) in LD, SM and ST muscles were greater (P < 0.05) or tended to be greater (P < 0.15) in the niacin group than in the control group.

Conclusions

The study shows that niacin supplementation induces muscle fiber transition from type II to type I, and thereby an oxidative metabolic phenotype of skeletal muscle in sheep as a model for ruminants. The enhanced capacity of skeletal muscle to utilize fatty acids in ruminants might be particularly useful during metabolic states in which fatty acids are excessively mobilized from adipose tissue, such as during the early lactating period in high producing cows.     

Genotyping glycogen storage disease type II and type V in cattle reared in the Czech Republic

Genotyping was carried out for glycogen storage disease type II and type V in seven cattle breeds. The analysis was carried out using the polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) method. In the breeds analysed [Charolais, Czech Spotted (Czech Simmental), Belgian Blue, Limousine, Blonde d'Aquitaine, Aberdeen Angus, and Beef Simmental sires reared in the Czech Republic], the recessive allele was not found in the PYGM (phosphorylase glycogen, muscle) responsible for the glycogen storage disease type V. In the same panel, the recessive allele in exon 7, exon 9 and exon 13 of the GAA (glucosidase alpha, acid), causing the glycogen storage disease type II was not found. Therefore, we have not revealed the recessives outside previous reported breeds. The knowledge of the breed-specific occurrence of inherited disorders facilitates focusing and reduces the costs of detecting the heterozygous carriers of recessive inherited disorders.     

Isolation of caprine herpesvirus type 1 in Spain

Two strains of caprine herpesvirus type 1 (CpHV-1) were isolated after the experimental reactivation of two seropositive goats in Spain. Viral DNA from these isolates was compared with DNA from bovine herpesvirus type 1 and CpHV-1 reference strains by restriction endonuclease analysis. The two Spanish isolates were closely related but could easily be distinguished from each other and from the reference strains.     

湖北省蛋鸡『153』标准化养殖模式

为了推动我省蛋鸡业的可持续发展,改变目前落后的养殖方式,促进蛋鸡产业的升级和整体素质提高,实现蛋鸡生产的优质、高产、高效、安全,湖北省畜牧技术推广总站组织编印并推广了“蛋鸡’153’标准化养殖模式”。     

Characterization of porcine circovirus type 2 in Taiwan

In an effort to understand the genetic diversity of porcine circovirus type 2 (PCV2) and the prevalence of PCV2 infection in Taiwanese herds, we have sequenced the complete genomes from PCV2-infected specimens and individually measured the antibody titer against PCV2 from pigs reared in Taiwan between the years 2000 and 2002. A total of 623 specimens originating from pigs displaying varied clinical signs were screened with the polymerase chain reaction (PCR). Results showed that 309 pigs (49.6%) tested positive for PCV2. Eight of the positive specimens were used for the amplification of the complete viral genome. Sequence comparison of the complete genomes indicated that the 8 Taiwanese PCV2 isolates shared 95-99% similarity. Phylogenetic analysis of all 40 PCV2 isolates from North America, Europe, Asia and Taiwan revealed that those isolates were grouped together in one large group containing two minor subgroups. The Taiwanese PCV2 isolates were classified into the two minor subgroups. The prevalence of serum antibodies to PCV2 in pigs was investigated, and results showed that approximately 83.5% of the pigs in Taiwan were seropositive. Finishing pigs possess the highest titers of antibodies, while 9-week-old pigs contained the lowest titers for specific antibodies. Our results suggest that PCV2 infections have become common in Taiwanese pig farms.     

禽流感新型疫苗研究进展

禽流感(AvianInfluenza,AI)是由A型流感病毒引起的禽类(家禽和野禽)的一种从呼吸系统到严重全身性败血症等的多种疾病综合症,该病毒属于正黏病毒科。该病被世界动物卫生组织(OIE)规定为A类传染病,也被我国列为一类动物疾病。自本病1878年在意大利的鸡群中首次暴发,其后在世界各地,包括北美、南美、北非、中东、远东、英国和前苏联等地都有暴发流行的报导,尤其是2003年底至2004年2月,H5N1亚型高致病力禽流感病毒引起的禽流感先后在亚洲的越南、泰国、韩国、日本、中国等国家的禽类中出现大面积流行,造成重大的经济损失,并且在此次暴发流…     

荷斯坦奶牛体型线性评定及其性状与产奶量的相关性分析

采用9分制线性评定法对湖北宜昌地区饲养的荷斯坦奶牛进行体型线性评定，9分制奶牛体型外貌评定系统分为5大块，即结构／容量、尻部、肢蹄、泌乳系统和乳用特征，共24个性状，对每一性状给予1．9分的评分，最终根据此评分，选育高产、健康、优秀、长寿的优质牛群以获得最好的经济效益。     

Molecular cloning of type I collagen cDNA and nutritional regulation of type I collagen mRNA expression in grass carp

Grass carp (Ctenopharyngodon idellus) are important Chinese freshwater fish, and in China, the faba bean has been used as the sole food source for grass carp to transform them into crisp grass carp. Because of this, crisp grass carp has become an economically important fish because of its increased muscle hardness. To study the nutritional regulation of type I collagen in faba bean‐fed grass carp, we isolated type I collagen alpha 2 (COL1A2) on the basis of our isolation of COL1A1. The COL1A2 cDNA was found to be 4899 bp in length and included a 4059‐bp coding sequence (CDS) and encoded a polypeptide of 1352 AA. The protein peptide molecular weight was 127.39 kD, and the theoretical isoelectric point was 9.37. The COL1A2 protein possessed five α‐helixes, eight β‐sheets, 16 regions of triple helical repeats, 21 low‐complexity regions, 10 function domains and two zinc‐binding sites; however, no calcium‐binding sites were observed. The mRNA expression of COL1A1 and COL1A2 was assessed in eight tissues (muscle, hepatopancreas, intestine, gills, skin, fin, kidney and spleen) from grass carp and crisp grass carp by semi‐quantitative RT‐PCR. Expression of COL1A1 in the muscle, intestines and skin of crisp grass carp was higher than that in grass carp, and expression of COL1A2 in the muscle, gills, fin and skin of crisp grass carp was higher than that in grass carp. In the muscle of crisp grass carp, expression of COL1A1 and COL1A2 was higher than that in grass carp, which was further confirmed by real‐time PCR, and collagen content also was enhanced. These results demonstrated that type I collagen was closely related to the increased muscle hardness of faba bean‐fed grass carp.     

Evaluation of heat-labile enterotoxins type IIa and type IIb in the pathogenicity of enterotoxigenic Escherichia coli for neonatal pigs

Type II heat-labile enterotoxins (LT-II) have been reported in Escherichia coli isolates from humans, animals, food and water samples. The goal here was to determine the specific roles of the antigenically distinguishable LT-IIa and LT-IIb subtypes in pathogenesis and virulence of enterotoxigenic E. coli (ETEC) which has not been previously reported. The prevalence of genes encoding for LT-II was determined by colony blot hybridization in a collection of 1648 E. coli isolates from calves and pigs with diarrhea or other diseases and from healthy animals. Only five isolates hybridized with the LT-II probe and none of these isolates contained genes for other enterotoxins or adhesins associated with porcine or bovine ETEC. Ligated intestinal loops in calves, pigs, and rabbits were used to determine the potential of purified LT-IIa and LT-IIb to cause intestinal secretion. LT-IIa and LT-IIb caused significant secretion in the intestinal loops in calves but not in the intestinal loops of rabbits or pigs. In contrast, neonatal pigs inoculated with isogenic adherent E. coli containing the cloned genes for LT-I, LT-IIa or LT-IIb developed severe watery diarrhea with weight loss that was significantly greater than pigs inoculated with the adherent, non-toxigenic parental or vector only control strains. The results demonstrate that the incidence of LT-II appeared to be very low in porcine and bovine E. coli. However, a potential role for these enterotoxins in E. coli-mediated diarrhea in animals was confirmed because purified LT-IIa and LT-IIb caused fluid secretion in bovine intestinal loops and adherent isogenic strains containing cloned genes encoding for LT-IIa or LT-IIb caused severe diarrhea in neonatal pigs.     

Immune response phenotype induced by controlled immunization of neonatal pigs varies in type 1:type 2 bias

Immune response (IR) of pigs varies by litter and by individual such that ratios of type-1 and type-2 IR differ. Estimates of heritability for antibody and cell-mediated IR suggest that genotype and the environment contribute approximately 20% and 80% to this variation. It is hypothesized that the IR phenotype of outbred neonatal pigs is immature and variable progressing with age from type-2 bias to a more balanced phenotype. To test this, pigs were IR phenotyped by a standardized protocol using two intramuscular injections of the combined type-1 and type-2 antigens (Ag) Candida albicans (CA) and hen egg white lysozyme (HEWL). Immune response was measured by wheal and flare reaction to HEWL and double skin fold thickness (DSFT) response to each Ag injected intradermally at 35 days of age. Blood was collected at 14 and 35 days of age to measure immunoglobulin IgG(1), IgG(2) and IgE isotype-relatedness of antibody (Ab) to CA and HEWL. Comparison was made between two different groups of pigs (A) and (B), from the same herd tested separately at an interval of two and a half years. An unexpected group difference in IR bias was observed. Bias in IR was not consistently toward type-2. Increase in DSFT to CA, an indicator of type-1 IR, was greater in A while frequency of wheal and flare to injection of HEWL, a type-2 IR correlate, was greater in B. Frequency of individuals with positive serum Ab activity to both Ags was greater in B than A for most isotypes. Ratios of Ab activity by type-1 and 2 isotypes and DSFT to type-1 and 2 Ags indicate diminished type-1 relative to type-2 biased IR response in B. We conclude that in normal neonatal pigs under standard husbandry IR bias is not invariably toward type-2. Phenotype varied between groups in type-1:type-2 bias with implications for protective and immunopathogenic IR. While the etiology was not pursued it is possible that unidentified environmental variables may have induced this change in IR phenotype.