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排序方式: 共有66条查询结果,搜索用时 31 毫秒
1.
RO Pinho BS Camilo DMA Lima FAC Villadiego JCM Vergara HH Shiomi RE Cardoso PS Lopes JD Guimarães 《Reproduction in domestic animals》2018,53(2):393-400
The objective was to study the use of ultrasound as a complementary test in the breeding soundness evaluation in male pigs and study the pattern of echogenicity of the testicular parenchyma in boars of different racial groups. Twenty‐six adult boars from four different racial groups were used, 10 from the Piau breed (group 1), four from the commercial and finishing group (group 2), six Pietrain breed (group 3) and six from the Duroc breed (group 4). All animals were evaluated for breeding soundness evaluation and the ultrasound examination of the testicles. The groups of animals that were evaluated showed no difference in the main semen parameters that were evaluated, except for the sperm volume, concentration of the ejaculated sperm and the supravital staining; the lowest figures were for the animals from the Piau breed (group 1). In relation to the testicular biometrics, Duroc animals (group 4) had a greater scrotal width compared to the other groups. But when we assessed the intensity of pixels of the testicles, there was a difference between groups. The groups 2 (finishing animals), 3 (Pietrain) and 4 had no difference between themselves. Group 3 had greater pixel intensity in relation to group 1. Of the 26 animals studied, five showed an abnormality during ultrasound evaluation, like hydrocele, hyperechoic mass in the testicular parenchyma, cyst in the head of the epididymis and the presence of fluid in the head and tail of the epididymis. The various animal groups studied did not differ in the principal reproductive parameters evaluated, showing that despite the great variability of reproductive traits between breeds and within the same breed, the breeding soundness evaluation, the more complete it is, is essential for the selection of breeders and the ultrasonography of the reproductive system becomes an important addition in this examination. 相似文献
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Penetration resistance, bulk density, soil water content and root growth of oats were intensively studied in a tilled and an untilled grey brown podzolic loess soil. Bulk density and penetration resistance were higher in the top layer of the untilled soil compared with the tilled soil. In the latter, however, a traffic pan existed in the 25–30 cm soil layer which had higher bulk density and penetration resistance than any layer of the untilled soil. Above the traffic pan, rooting density (cm root length per cm3 of soil) was higher but below the pan it was lower than at the same depth in the untilled soil. Root growth was linearly related to penetration resistance. The limiting penetration resistance for root growth was 3.6 MPa in the tilled Ap-horizon but 4.6-5.1 MPa in the untilled Ap-horizon and in the subsoil of both tillage treatments. This difference in the soil strength-root growth relationship is explained by the build up of a continuous pore system in untilled soil, created by earthworms and the roots from preceding crops. These biopores, which occupy < 1% of the soil volume, can be utilized by roots of subsequent crops as passages of comparatively low soil strength. The channeling of bulk soil may counteract the possible root restricting effect of an increased soil strength which is frequently observed in the zero tillage system. 相似文献
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Cryopreservation of Piau‐Breed Wild Boar Sperm: Assessment of Cooling Curves and Centrifugation Regimes 下载免费PDF全文
HH Shiomi RO Pinho DMA Lima JB Siqueira MCR Santos EV Costa PS Lopes SEF Guimarães JD Guimarães 《Reproduction in domestic animals》2015,50(4):545-553
This study aimed to assess the effects of different cooling curves and centrifugation regimes used in cryopreservation protocols on the post‐thaw viability of Piau‐breed wild boar (Sus scrofa) sperm using in vitro assessment tests. Two centrifugations (800 g for 10 min and 2400 g for 3 min) and two cooling curves (conventional cooling using nitrogen vapour – freezing 1 and automated cooling using a programmed freezing machine – freezing 2) were tested. Therefore, the treatments were divided into M3 – centrifugation at 2400 g for 3 min and freezing 2; M10 – centrifugation at 800 g for 10 min and freezing 2; R3 – centrifugation at 2400 g for 3 min and freezing 1; and R10 – centrifugation at 800 g for 10 min and freezing 1. No significant differences (p > 0.05) between treatments occurred post‐thawing regarding the total sperm motility means recorded. The mean values of the different treatments were not different from each other regarding the supravital staining (SV), hypo‐osmotic test (HO), sperm–egg binding assay or sperm morphology. This study showed that both the cooling curve and the centrifugation regime affected the quality of post‐thaw sperm, and centrifugation for shorter times and cooling curves using automated cooling are the most suitable for minimizing sperm injury. 相似文献
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A. Hesse 《The Journal of small animal practice》1990,31(12):599-604
The incidence of canine urolithiasis was found to lie between 0–5 to 1 per cent of the canine population. Epidemiological and analytical data were collected for 1731 urinary stones, and causal relationships investigated. Calculi were found in 72 breeds. While they were relatively common among dachshunds, dalmatians, cocker spaniels, Pekingese, bassets, poodles, schnauzers and small terrier breeds, urinary stones were relatively rare among German shepherd dogs, boxers, collies, chow chows, old English sheepdogs, spitz and rottweiler breeds. Struvite, which was found in 55-6 per cent of all calculi, proved to be the most common constituent, followed by cystine (22-5 per cent) and ammonium urate (6-6 per cent). Xanthine calculi were rare (six cases), while silicium dioxide calculi were present in only one case. The likelihood of calculi in male animals was twice that of bitches, although the latter were found to be more prone to infection of the urinary tract. Adiposity was present in 29 per cent of all dogs with calculi. The average age of the animals was seven years. In 98-7 per cent of all cases the calculi were found in the lower urinary tract, and surgical removal of the stones was required in 87-5 per cent of cases. The main types of calculi appear among specific breeds, which indicates that a careful breeding programme may help to reduce the frequency of urinary calculi. 相似文献
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Effects of bovine parainfluenza-3 virus on phagocytosis and phagosome-lysosome fusion of cultured bovine alveolar macrophages 总被引:1,自引:0,他引:1
Bovine parainfluenza-3 virus (PI-3V) replicated in cultured bovine alveolar macrophages (BAM) in vitro. Cytopathic changes included spindle cell and giant cell formation, diffuse cell lysis, and cellular detachment progressing to total destruction of the monolayer. Direct immunofluorescent microscopy revealed viral antigen in greater than 90% of BAM on post-inoculation day (PID) 3. Virus titers in culture supernatants increased by a factor of 1.6 X 10(6) TCID50 by PID 6. Candida glabrata was phagocytized by a similar proportion of glass-adherent PI-3V-infected and sham-inoculated control BAM. However, when the number of glass-adherent cells available for assay was taken into account (normalization), the percentage of phagocytic PI-3V-infected BAM was significantly lower than that of the control cells at PID 5 and 7 (P less than 0.01). Phagosome-lysosome fusion assays had a marked reduction of fusion activity in PI-3V-infected BAM as compared with that of control BAM. Proportions of infected cells that showed fusion were approximately 50% of that of the control cells at PID 4 and 6 (P less than 0.05). Normalization of these values reduced the fusion rate of PI-3V-infected BAM to 34% of that of control BAM (P less than 0.01). 相似文献
9.
Onion bulbs of 3 inbred lines were stored during the winter in 4 different storage temperature regimes. Traits directly and indirectly associated with seed production were studied the following summers. The inbred lines differed in their responses and many traits were affected by the storage treatments. The storage treatment of 10°C for 12 weeks followed by 2° C for 12 weeks resulted in a significantly higher seed yield than did storage at 2° C throughout the entire period. Inbred 2399 had a higher seed yield than the other inbreds. Associated with high seed yields of 2399 was early flowering, a high number of leaves/bulb, tall seed stalks and a high number of florets/bulb. 相似文献
10.
Timely onset of postpartum ovarian activity is vital for optimal reproductive performance of dairy cows. Much depends upon genetic constitution of an animal although several factors interplay to govern the onset of postpartum ovarian activity. South Asian zebu cattle have much longer service period when compared with other exotic or crossbred cattle reared in the same Asian environment, which suggests differences in their genetic makeup. However, the cows with same genetic configuration expressed better reproductive potential when reared under different environment, such as in Brazil and Mexico, which suggests the role of extrinsic factors such as management, nutrition, environment and disease conditions. Better management of animals (provision of proper shade, water and housing, efficient oestrous detection and timely insemination), good quality nutrition supplemented with appropriate minerals and vitamins, prevention of diseases (vaccination, deworming, suitable therapeutic interventions) and application of biotechnology have helped in improving postpartum ovarian activity and, therefore, reproductive performance of zebu cattle in Asia. No comprehensive study appears to have been carried out on the various aspects of reproduction in zebu cattle reared under South Asian socio-agro-climatic conditions. This paper is a modest effort to collect what ever information available and to critically review the postpartum ovarian activity in zebu cattle with special reference to the effect of the various managemental practices and pharmacological interventions. 相似文献