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1.
At the time of AI following Ovsynch protocol, a total of 51 buffaloes were randomly divided in a first group (n = 30) subjected to conventional AI into the uterine body with 20 million non-sex sorted frozen-thawed spermatozoa, while a second group (n = 21) was inseminated near the utero-tubal junction (UTJ) ipsilateral to the ovary carrying the preovulatory follicle with 2.5 million live (4 million total) sex-sorted frozen-thawed spermatozoa. The semen used for flowcytometric sorting was collected and processed on a farm in Italy, and then shipped to a laboratory in Germany. Eleven buffaloes were inseminated with X-chromosome bearing spermatozoa and 10 with Y-chromosome bearing spermatozoa. Conception rates after conventional and UTJ inseminations were 43.3% (n = 13) and 42.8% (n = 9) respectively (p = 0.97). Eight of the nine foetuses obtained after insemination with sexed spermatozoa corresponded to the sex as predicted by the cell sorting procedure (five male and four female foetuses by ultrasound vs six male and three female foetuses by cell sorting). In conclusion, for the first time buffalo semen has been successfully subjected to procedures for flowcytometric sperm sorting and freezing. Low doses of sexed spermatozoa have been deposited near the UTJ giving conception rates similar to those of conventional AI with full dose.  相似文献   
2.
Nutraceuticals have gained immense importance in poultry science recently considering the nutritional and beneficial health effects of their constituents. Besides providing nutritional requirements to birds, nutraceuticals have beneficial pharmacological effects, for example, they help in establishing normal physiological health status, prevent diseases and thereby improve production performance. Nutraceuticals include amino acids, vitamins, minerals, enzymes, etc. which are important for preventing oxidative stress, regulating the immune response and maintaining normal physiological, biochemical and homeostatic mechanisms. Nutraceuticals help in supplying nutrients in balanced amounts for supporting the optimal growth performance in modern poultry flocks, and as a dietary supplement can reduce the use of antibiotics. The application of antibiotic growth enhancers in poultry leads to the propagation of antibiotic-resistant microbes and drug residues; therefore, they have been restricted in many countries. Thus, there is a demand for natural feed additives that lead to the same growth enhancement without affecting the health. Nutraceuticals substances have an essential role in the development of the animals’ normal physiological functions and in protecting them against infectious diseases. In this review, the uses of amino acids, vitamins and minerals as well as their mode of action in growth promotion and elevation of immune system are discussed.  相似文献   
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Foot and mouth disease (FMD) is a highly transmissible viral infection of cloven hooved animals associated with severe economic losses when introduced into FMD-free countries. Information on the impact of the disease in FMDV-endemic countries is poorly characterised yet essential for the prioritisation of scarce resources for disease control programmes. A FMD (virus serotype SAT2) outbreak on a large-scale dairy farm in Nakuru County, Kenya provided an opportunity to evaluate the impact of FMD on clinical mastitis and culling rate. A cohort approach followed animals over a 12-month period after the commencement of the outbreak. For culling, all animals were included; for mastitis, those over 18 months of age. FMD was recorded in 400/644 cattle over a 29-day period. During the follow-up period 76 animals were culled or died whilst in the over 18 month old cohort 63 developed clinical mastitis. Hazard ratios (HR) were generated using Cox regression accounting for non-proportional hazards by inclusion of time-varying effects. Univariable analysis showed FMD cases were culled sooner but there was no effect on clinical mastitis. After adjusting for possible confounders and inclusion of time-varying effects there was weak evidence to support an effect of FMD on culling (HR = 1.7, 95% confidence intervals [CI] 0.88-3.1, P = 0.12). For mastitis, there was stronger evidence of an increased rate in the first month after the onset of the outbreak (HR = 2.9, 95%CI 0.97-8.9, P = 0.057).

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-015-0173-4) contains supplementary material, which is available to authorized users.  相似文献   
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A physical map of the 1-gigabase bread wheat chromosome 3B   总被引:2,自引:0,他引:2  
As the staple food for 35% of the world's population, wheat is one of the most important crop species. To date, sequence-based tools to accelerate wheat improvement are lacking. As part of the international effort to sequence the 17-billion-base-pair hexaploid bread wheat genome (2n = 6x = 42 chromosomes), we constructed a bacterial artificial chromosome (BAC)-based integrated physical map of the largest chromosome, 3B, that alone is 995 megabases. A chromosome-specific BAC library was used to assemble 82% of the chromosome into 1036 contigs that were anchored with 1443 molecular markers, providing a major resource for genetic and genomic studies. This physical map establishes a template for the remaining wheat chromosomes and demonstrates the feasibility of constructing physical maps in large, complex, polyploid genomes with a chromosome-based approach.  相似文献   
8.
Woodchucks (Marmota monax) infected with woodchuck hepatitis virus (WHV) represent a highly valuable laboratory model of hepatitis B virus (HBV) infection, in which molecular, immunological and pathological events occurring in infected humans are adequately reflected. To advance studies on T cell immune responses and propagation of hepadnavirus in T lymphocytes in this animal model, we determined the complete sequence of woodchuck interleukin-2 (wIL-2) cDNA by utilizing RNA ligase-mediated rapid amplification of cDNA ends (RLM-RACE) reaction. The wIL-2 sequence revealed a single open reading frame encoding for the predicted precursor protein comprised of a signal peptide and a 134 amino acid-long mature protein. The mature wIL-2 protein produced in the Escherichia coli expression system, designated as ec-rwIL-2, was found to be immunogenic but not biologically active. In contrast, precursor wIL-2 protein cloned into baculovirus transfer vector and expressed in Sf9 cells, designated as bac-rwIL-2, demonstrated functional competence. Further, bac-rwIL-2 was able to stimulate proliferation and to induce multiple daughter cell generations in woodchuck T cells, as well as facilitated the survival of standard IL-2-dependent mouse CTLL-2 cells in culture. Western blot analysis of bac-rwIL-2 using antibodies generated against ec-rwIL-2 revealed a single protein band of 15.5kDa. The availability of biologically active recombinant wIL-2 should facilitate ex vivo studies on functional competence of woodchuck T lymphocytes derived from different stages of hepadnaviral hepatitis and assist in recognizing their contribution to the pathogenesis of liver injury in the woodchuck model of hepatitis B.  相似文献   
9.
AIMS: To assess the sensitivity of non-angiographic contrast-enhanced computed tomography (CT) to determine the presence of vascular invasion of cranial mediastinal masses in dogs and a cat, and to evaluate the association between vascular invasion and peri-operative mortality.

METHODS: A retrospective study was conducted on 25 dogs and one cat. CT scans were completed with slices ranging from 2 to 10 mm. CT images were evaluated by a board-certifi ed radiologist blinded to previous diagnoses and surgical fi ndings. Each CT study was evaluated for vascular invasion, defi ned as disruption of the vessel wall and extension of the mass into the vessel lumen. Data retrieved from the surgery reports included surgical approach, whether vascular invasion was present, the surgeon's decision on operability, and post-operative complications.

RESULTS: Computed tomographic evaluation revealed 25/26 masses had no evidence of vascular invasion. During surgical exploration, 10/26 masses were found to invade major regional vasculature; the cranial vena cava (CVC) was the vessel most commonly invaded (7/10 animals), and 4/7 (57%) patients with invasion of the CVC were euthanised or died in the perioperative period, from surgical or disease-related problems, which was signifi cantly higher than patients without vascular invasion (p=0.045).

CONCLUSIONS: Non-angiographic contrast-enhanced CT was signifi cantly less sensitive for detecting vascular invasion of cranial mediastinal masses when compared with surgical evaluation. If the CVC was invaded by a tumour there was a signifi cant risk of death peri-operatively when compared with non-invasive cases.

CLINICAL RELEVANCE: Due to the signifi cantly higher mortality risk associated with invasion of the CVC, a more sensitive method than CT should be investigated to determine vascular invasion of mediastinal masses pre-operatively.  相似文献   
10.
Abstract

CASE HISTORY: A 5-year-old entire female Huntaway from a sheep and beef farm was one of four dogs that developed clinical signs including hypersalivation, depression, blindness and ataxia after the death of another dog. A 4-year-old female Huntaway farm dog from a second farm was observed to be sitting down more often than usual on the day after being fed part of a calf carcass that had been treated with an abamectin pour-on.

CLINICAL FINDINGS: The first dog was ataxic and depressed but did respond to sound. The second dog presented with an acute onset of blindness, mydriasis, absence of a menace response, hypersalivation, gait abnormalities (e.g. high stepping gait and ataxia), and depression. Other presenting signs included muscle tremors, dehydration and difficulty eating. No abnormalities were detected from routine haematology and biochemistry. Analysis of samples of plasma from both dogs revealed concentrations of abamectin of 0.149 mg/L and 0.260 mg/L for the first and second dogs, respectively. Buccal swabs taken from the first dog for DNA testing for the ABCB1 gene mutation, gave a negative result.

DIAGNOSIS: In addition to the presenting signs which suggested a toxicosis, both dogs had measurable concentrations of abamectin in plasma confirming exposure.

CLINICAL RELEVANCE: Farm dogs exposed to concentrated pour-on products containing abamectin have been poisoned and recover or die. The product labels do not carry any warnings as to the risk of poisoning to dogs. This paper discusses two incidents affecting six farm dogs, but the authors are aware of more toxicoses in farm dogs exposed to abamectin.  相似文献   
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