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81.
Retrospective analysis of records, from July 1987 to June 1991, of 1140 inspections of slaughtered pigs from 154 swine herds in the Pig Health Monitoring Scheme of South Australia was conducted to evaluate patterns of variation in the prevalence and severity of skin lesions typical of sarcoptic mange. An increase in the severity of sarcoptic mange in winter and spring was observed. There was a substantial reduction in the severity of mange over the period of monitoring. These observations support the role of monitoring at slaughter in the management of endemic disease. They provide some basis for refining control programs for mange to improve cost-effectiveness.  相似文献   
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Many strains of enterotoxigenic Escherichia coli (ETEC) that cause diarrhoea in young piglets secrete a heat-labile enterotoxin (LTp) that binds to specific glycoconjugates on porcine intestinal epithelial cells. Binding of LTp to an appropriate glycoconjugate facilitates the uptake and trafficking of the toxin into the cell, where it stimulates intracellular changes that promote fluid secretion and diarrhoea. The objective of the current study was to identify the LTp-binding glycoconjugates on porcine intestinal epithelial cells, the natural target cells for LTp. We found that LTp binds, in an age-correlated manner, to an acidic glycosphingolipid (GSL) that co-migrated with GM1 on thin-layer chromatography (TLC), a small acidic GSL that appears to be a sulphatide, a neutral GSL that co-migrated with neolactotetraglycosylceramide (nLc4) on TLC, and two glycoproteins (36 and 205 kDa). Of these potential LTp receptors, the GM1-co-migrating GSL was detected most intensely in young animals, while the other four LTp-binding glycoconjugates were detected most intensely in older pigs (54 weeks). Since ETEC primarily cause disease in young piglets, the GM1-co-migrating GSL is the most likely candidate for a functional LTp receptor.  相似文献   
85.
A non-pharmaceutical, dietary option may be useful to manage clinical pseudopregnancy (PSP). To describe the effect of short-term food restriction on canine PSP, 16 privately owned, overtly pseudopregnant bitches were randomly assigned to one of the following groups: Limit-fed (increasing amounts of a restricted maintenance: 50%, 40%, 30% restriction for 2, 3 and 2 days respectively) during 7 days (n = 8) or Maintenance-fed of the same food and period (n = 8). The bitches were physically examined and blood samples were taken for prolactin and progesterone determinations on days 2, 5 and 8. By day 8, none of the bitches had completely regressed the condition although all (8/8) the animals of the Limit-fed and two (25%) of the Maintenance-fed group improved in condition decreasing mammary size and secretion (p < 0.05). No day or group effects were observed for serum prolactin and progesterone concentrations (>0.05). It is concluded that although an 8-day food restriction did not cure PSP, it seemed to hasten PSP signs involution in these bitches. No endocrine change was related to these clinical findings.  相似文献   
86.

Background

Demodex gatoi is unique among demodectic mites. It possesses a distinct stubby appearance, and, instead of residing in the hair follicles, it dwells in the keratin layer of the epidermis, causing a pruritic and contagious skin disease in cats. Little is known of the occurrence of D. gatoi in Europe or control of D. gatoi infestation.

Case presentation

We describe D. gatoi in 10 cats, including five Cornish Rex, two Burmese, one Exotic, one Persian and one Siamese, living in six multi-cat households in different locations in Finland containing 21 cats in total. Intense pruritus was the main clinical sign. Scaling, broken hairs, alopecia and self-inflicted excoriations were also observed.Diagnosis was based on finding typical short-bodied demodectic mites in skin scrapings, skin biopsies or on tape strips. Other pruritic skin diseases, such as allergies and dermatophytoses, were ruled out. In one household, despite finding several mites on one cat, all six cats of the household remained symptomless.Amitraz used weekly at a concentration of 125-250 ppm for 2-3 months, proved successful in three households, 2% lime sulphur weekly dips applied for six weeks in one household and peroral ivermectin (1 mg every other day for 10 weeks) in one household. Previous trials in four households with imidacloprid-moxidectin, selamectin or injected ivermectin given once or twice a month appeared ineffective.

Conclusion

D. gatoi-associated dermatitis is an emerging contagious skin disease in cats in Finland. Although pruritus is common, some cats may harbour the mites without clinical signs. In addition, due to translucency of the mites and fastidious feline grooming habits, the diagnosis may be challenging. An effective and convenient way to treat D. gatoi infestations has yet to emerge.  相似文献   
87.
Puberty is a stage of sexual development determined by the interaction of environmental factors and genetic mechanisms. Among them, thyroid function plays a key role in sexual development and spermatogenic function and is under the control of several genes, including the well‐described thyroglobulin gene (TG). Previous reports have shown genetic association between thyroid function and selected single nucleotide polymorphisms (SNPs) in taurine cattle. Therefore, the identification of genetic mechanisms involved in the regulation of this trait can assist with the selection for early pubertal bulls, thus improving genetic progress in livestock breeding. The aim of this study was to validate the association between TG SNPs and age at puberty in zebuine bulls. Three SNPs (rs110406764, rs109662686, rs109057985) were genotyped in 159 Guzerat animals using SEQUENOM technology. Results showed a significant association (< .05) between the studied SNPs and puberty age, in agreement with our previous reports in a taurine breed. Interestingly, allele frequencies were different from those already reported, being GAT the most favourable allele for age at puberty in Guzerat (94.4 days lower). Overall, our findings corroborate previous reports and reinforce the importance of genetic influence in the regulation of sexual development and puberty through a thyroid pathway in zebuine cattle.  相似文献   
88.
Regucalcin (RGN) is a calcium‐regulating, anti‐apoptotic, antioxidative and antiproliferative multifunctional protein predominantly seen in liver and kidney. All these functions are very crucial during spermatogenesis and sperm maturation process until fertilization of the ovum. Although many studies have reported the wide distribution of regucalcin in the male reproductive tract of the rat, human and bovine, its presence in spermatozoa is yet to be demonstrated wherein calcium has a pivotal role in the transport, capacitation, acrosomal reaction and further fusion with ova. Here, we detected the expression of regucalcin mRNA and protein in buffalo spermatozoa using real‐time PCR and Western blot, respectively. The study detected two new regucalcin isoforms of 44 kDa and 48 kDa size along with the reported 34‐kDa, 28‐kDa and 24‐kDa isoforms, wherein the 34‐kDa isoform was found to be membrane associated in spermatozoa. Further, immunocytochemistry study localized the regucalcin protein in the acrosomal region of the caudal and ejaculated buffalo spermatozoa while it was detected in both cytoplasm and acrosomal region of testicular spermatozoa. This discovery of RGN in spermatozoa and localization in the acrosomal region will help to focus researchers to see its role in calcium‐related functions like capacitation, acrosomal reaction and membrane fusion. Overall, regucalcin may be a new fertility marker in buffalo and can be utilized for infertility treatments.  相似文献   
89.
Heat shock proteins (HSPs) act as molecular chaperones with important regulatory functions. HSPs are considered to be essential factors in animal reproduction. In view of seasonal variations in the secretory activity of the reproductive tract of mature roe deer (Capreolus capreolus), the aims of this study were to identify HSPs in the epididymides and compare the expression of the identified proteins in three periods of the reproductive season. Two‐dimensional polyacrylamide gel electrophoresis revealed the highest number of polypeptides in homogenates of epididymal tissues and in caput, corpus and cauda epididymal fluids throughout the reproductive season. Epididymal tissue homogenates and epididymal fluids were analysed by tandem mass spectrometry (MS/MS) to reveal 31 polypeptides with enzymatic activity, including polypeptides with antioxidant properties, structural and cell signalling functions. Moreover, among the identified polypeptides, five of them were similar to heat shock proteins: endoplasmin (Grp94); heat shock protein 90 kDa (HSP90); 78‐kDa glucose‐regulated protein (Grp78); chain A, the crystal structure of the human HSP70 ATPase domain and heat shock protein beta‐1 isoform X. The concentrations of the analysed polypeptides, expressed in optical density units (ODU), differed significantly (p ≤ .05) across the examined periods of the reproductive season. The highest ODU values for almost all analysed proteins were observed during the rutting period. The presence of HSPs in the epididymal tissues and fluids of roe deer in different periods of the reproductive season could indicate that those proteins play an important role in sperm maturation in the epididymis.  相似文献   
90.
本着遵照标准,结合实际的原则,阐述了动物用防疫耳标强度指标和字迹附着力指标等主要质量指标的检测方法,并通过大量试验证实其具有简单、科学、有效等特点,在实际检测过程中具有一定的推广应用价值。  相似文献   
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