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71.
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An indirect microELISA test was performed for detection of maedi-visna antibodies in ovine and caprine species. The antigen consisted in viral particles, highly purified by successive ultracentrifugations.

By comparative testing of 934 sera in ELISA and gel immunodiffusion, we found a good correlation between these two te ts, and moreover, ELISA revealed another 11.3% of positive samples. The precocity of this ELISA was shown by experimental infection of sheep with different strains of maedi-visna: positive sera were detected 7 weeks post-infection, instead 4–5 months with gel immunodiffusion. The complement fixation test was compared with gel immunodiffusion and was found the less sensitive.

This ELISA test appeared to be satisfactory, and may be used for early diagnosis of maedi-visna infection.  相似文献   

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The study addresses the first two weeks of piglet weaning and is aimed at i) identifying new probiotic strains of Bifidobacterium spp. and non-digestible oligosaccharides (NDO) able to increase the level of autochthonous bifidobacteria in the gut, and ii) finding the best probiotic doses, and probiotic-NDO combinations for piglet growth and gut health.Initially, on a total of 60 pigs we administered 12 strains of 4 bifidobacteria species taken from our collection of strains of different ecological origin. We found the most promising probiotic candidates to be two strains of B. animalis subsp. lactis (M 354 and Ra 18) and one strain of B. choerinum (Su 891), as these led to an increase in the number of viable bifidobacteria in the caecum. In a second trial, a different set of 64 piglets were fed a diet containing a galacto-oligosaccharide (1%) from milk whey, and two fructo-oligosaccharides (4%) from chicory inulin and sugar beet (SbFOS). There was virtually no effect on the hindgut microbiota, except for SbFOS at 4% which tended to increase the endogenous bifidobacteria. Then, in a third trial employing 128 weaning pigs, the probiotic strains Ra 18 and Su 891 were tested individually, at different doses (0; 107; 109; 1011 per pig per day) and combined with 0% or 2% SbFOS supplementation. It was found that Ra 18 improved the live weight growth linearly, while the Su 891 did not. The FOS supplementation showed no interaction with the Ra 18 or Su 891 probiotics for growth performance and no effect on this response criterion.Our selection procedure has highlighted that B. animalis subsp. lactis Ra 18, at 1011 CFU per pig per day, appears to be the best probiotic choice for improved growth performance in weaning piglets.  相似文献   
75.
Computer-assisted sperm morphometry analysis (CASMA) was used in this study to identify sperm morphometric subpopulations in Iberian red deer epididymal sperm samples. Epididymal sperm samples were collected from 37 mature stags and were divided. One portion was diluted in a Tris–citrate–egg yolk medium. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours using a conventional protocol. After thawing, sperm smears were prepared as described for extended samples. All slides were air-dried and stained with Hemacolor®. The sperm-head dimensions for a minimum of 145 sperm-heads were analyzed from each sample by means of the Sperm-Class Analyser®, and the mean measurements recorded. Each sperm-head was measured for four primary sperm-head parameters, and five parameters of head shape. All sperm morphometric parameters evaluated were placed in a statistical database and a multivariate cluster analysis was performed. The clustering analyses, based on 10 867 individual spermatozoa, revealed the existence of three subpopulations (SP1, SP2, SP3) of spermatozoa with different morphometric characteristics (p  <  0.001). The proportion of spermatozoa present in any of the three subpopulations remained constant (p  >  0.05) through the cryopreservation process. Pre-freeze and post-thaw sperm quality was in vitro evaluated by microscopic assessments of individual sperm motility and of plasma membrane and acrosome integrities. In conclusion, our results show that applying the CASMA techniques and multivariate cluster analyses, it was possible to determine that three subtle subpopulations of spermatozoa with different morphometric characteristics coexist in red deer semen.  相似文献   
76.
This study was designed to evaluate the effectiveness of a luteinizing hormone releasing hormone (LHRH) fusion protein immunization on reproductive traits in ram lambs including the changes in histology and ultrasonographic appearance of testis. Thirty native ram lambs at 19 weeks of age were divided into control (C, n = 10), immunization (I, n = 10) and castration (E, n = 10) groups. Animals in immunization group were immunized against LHRH using ovalbumin‐LHRH‐7 (OL) protein generated by recombinant DNA technology as a primary and a booster injection at 19 and 23 weeks of age respectively. Animals were bled via jugular venepuncture at 2‐week intervals to determine LHRH antibody and testosterone concentrations. Bi‐weekly ultrasonographic examination of the testes was performed to determine the changes in ultrasonographic appearance as the age increased. Biopsied testicular tissues taken at 19, 29 and 41 weeks age were also evaluated. At 41 weeks of age, animals were slaughtered. Semen and epididymis were evaluated for the presence of sperm cells. Testicular development and sperm production were suppressed in the immunized animals. Semineferous tubule diameters decreased, basal membrane of the tubule was thickened and hyalinized in immunized ram lambs. While testes of control animals gained their normal ultrasonographic appearance as the age increased, immunized animals had uniform hypoechogenic testicular structure as observed at 19 weeks of age until slaughter. Simultaneous histological and ultrasonographic evaluations indicated that the changes in testicular histology could partly be monitored via ultrasonographic imaging. Nevertheless, it is difficult to claim that ultrasonographic image reflects the exact changes in such instances. In conclusion, these results indicate that recombinant OL fusion protein is effective in immunocastration in ram lambs and has a potential to be used as an alternative to physical castration. Further research studies should be conducted to help assess reproductive status of testes from ultrasound images.  相似文献   
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Prostaglandin F2α (PGF2α) is a main luteolytic factor in vivo; however, its direct luteolytic influence on steroidogenic cells of bovine corpus luteum (CL) is controversial and not fully understood. The aim of the study was to clarify PGF2α action on bovine CL in different in vivo and in vitro conditions and to examine whether the contact among all main types of CL cells is necessary for luteolytic PGF2α action. In experiment 1, the bovine CL (day 15 of the oestrous cycle) was perfused using in vivo microdialysis system with dinoprost (an analogue of PGF2α) for 0.5 h. Dinoprost caused a short‐time increase in progesterone (P4), whose concentration decreased thereafter (at 6‐, 10‐, 12‐ and 24‐h after treatment). In experiment 2, the direct effect of PGF2α on P4 accumulation in CL steroidogenic cells cultured in monolayer (day 15 of the cycle) was determined. PGF2α after 24 h of incubation increased P4 accumulation in steroidogenic CL cells. In experiment 3 steroidogenic, endothelial CL and immune cells (day 15 of the cycle) were incubated with PGF2α in cocultures for 24 h in glass tubes and the levels of P4, stable metabolites of nitric oxide (NO) and leukotriene (LT) C4 were determined. Although PGF2α treatment increased P4 secretion in homogeneous steroidogenic CL cell culture, the decrease in P4 secretion in cocultures of all types of CL cells was observed. The secretion of NO and LTC4 increased after the treatment of PGF2α both in pure cultures of CL cells and in cocultures. The interactions between endothelial and immune cells with steroidogenic CL cells are needed for luteolytic PGF2α action within the bovine CL. Our results indicate that the cell coculture model, including the main types of CL cells, is the most approximate to study PGF2α role in vitro.  相似文献   
80.
The objectives of the present study were to determine the relationship between bacteriological findings, clinical signs and histopathological changes in postpartum metritis. Evaluation of the treatment efficiency of using systemic or intra‐uterine infusion of antibiotics with some hormonal preparations for the treatment of postpartum metritis. Data were collected from 50 buffalo cows with history of calving of more than 1 month. All buffaloes were subjected to detailed clinical examination including external inspection, vaginoscopy and transrectal palpation of the cervix, uterus and ovaries. Swabs for bacteriology and biopsies for histopathology were collected from uterine lumen from each buffalo included in the present study. Bacteria identified using API systems following aerobic and anaerobic cultures. Vaginal mucus scored for character, odour and estimation of polymorphonuclear cells (PMNs). Treatment conducted using oxytetracycline in local intrauterine infusion or systemically with hormonal treatment including prostaglandinF2α (PGF2α) and oestradiol benzoate. Results revealed that the most predisposing factor for postpartum uterine infection was retained placenta and toxic puerperal metritis. The most prevalent bacteria in uterine lumen were Escherichia coli, Archanobacterium pyogenes, Bacteroides fragilis and Fusobacterium necrophorum the most prevalent bacteria in buffaloes with postpartum metritis. A. pyogenes and F. necrophorum were an important pathogens causing severe uterine inflammation as found in histopathological examinations. Buffaloes with postpartum metritis showed good clinical cure when oxytetracycline injected systemically with PGF2α. Intrauterine infusion of oxytetracycline had no advantage for the treatment of uterine infection in buffalo cows with postpartum metritis. PGF2α improved clinical cure of buffaloes with postpartum metritis.  相似文献   
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