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31.
The aim of this study was to evaluate luteal dynamics in the Santa Inês ewes using colour Doppler (CD) ultrasonography. Oestrus was synchronized in nulliparous females (n = 18), and subsequently, they were only teased (n = 6) or teased and mated (n = 12). Blood samples were collected daily for plasma progesterone (P4) concentrations. Ultrasonographic images of corpora lutea (CL) in CD mode were obtained for further analysis in its largest diameter. The CD mode allowed an early sequential monitoring of CL that was visualized by the first time 0.77 ± 0.62 days after ovulation, with luteal area 29.68 ± 13.21 mm2. During the luteogenesis, a progressive increase was observed, followed by a plateau of luteal area, vascularization area and plasma concentrations of P4 reaching maximum values in D11 (124.0 ± 38.0 mm2, 52.78 ± 24.08 mm2 and 11.23 ± 4.89 ng/ml, respectively). In the luteolysis, the plasma concentrations of P4 decreased sharply, whereas luteal and vascularization area gradually. The vascularization area was positively correlated with plasma concentrations of P4 during the luteogenesis (r = 0.22) and luteolysis (r = 0.48). The luteal dynamics of Santa Inês ewes showed patterns similar to those observed in other sheep breeds studied. The CD ultrasonography has the potential to be used as a tool to assess luteal function in sheep.  相似文献   
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Lectins have been widely used to study the pattern of cellular glycoconjugates in numerous species. In the process of cellular apoptosis, it has been observed that changes occur in the membrane sugar sequences of these apoptotic cells. The aim of our work was to identify which lectins, out of an extensive battery of the same (PNA, SBA, HPA, LTA, Con‐A, UEA‐I, WGA, DBA, MAA, GNA, AAA, SNA), show affinity for germinal cells in apoptosis, at what stage of cell death they do so and in which germinal cell types they can be detected. For this, we studied testis sections during testicular regression in Syrian hamster (Mesocricetus auratus) subjected to short photoperiod. Several lectins showed an affinity for the glycoconjugate residues of germ cells in apoptosis: Gal β1,3‐GalNAcα1, α‐d ‐mannose, N‐acetylgalactosamine and l ‐fucose. Furthermore, lectin specificity was observed for some specific germinal cells and in certain stages of apoptosis. It was also observed that one of these lectins (PNA) showed affinity for Sertoli cells undergoing apoptosis. Therefore, we conclude that the use of lectin histochemistry could be a very useful tool for studying apoptosis in the seminiferous epithelium because of the specificity shown towards germinal cells in pathological or experimentally induced epithelial depletion models.  相似文献   
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Abstract

CASE HISTORY: A 2-year-old Hereford bull was lame for one week before becoming recumbent.

CLINICAL AND PATHOLOGICAL FINDINGS: The scrotum and ventral perineal region were cold and blackened caudally. The semimembranosus and semitendinosus muscles were firm on palpation. The bull was subject to euthanasia, and necropsy revealed that the skin and S/C tissues of the caudal half of the scrotum were grey and necrotic. The caudal and distal aspects of the semimembranosus and semitendinosus muscles were grey and necrotic to a depth of approximately 15 cm, and these changes appeared to track along fascial planes. The tissue had an offensive smell, and large amounts of flocculent, watery, brown fluid and some gas were present. Histology of affected muscle and S/C tissues revealed coagulative necrosis, with oedema and large numbers of bacteria that were predominantly Gram-positive rods. Adjacent blood vessels contained thrombi while the epidermis overlying the affected areas appeared diffusely necrotic, suggesting infarction. Culture of the fluid yielded a pure growth of Arcanobacterium spp., which was identified as Arcanobacterium haemolyticum, using an API Coryne biochemical test strip.

DIAGNOSIS: Necrotising fasciitis and myositis due to Arcanobacterium haemolyticum.

CLINICAL RELEVANCE: Arcanobacterium haemolyticum has not previously been reported as a cause of necrotising fasciitis in any species. Necrotising fasciitis is probably an under-reported condition in cattle due to its clinical similarity to clostridial disease.  相似文献   
34.
The decline in dairy herd fertility internationally has highlighted the limited impact of traditional veterinary approaches to bovine fertility management. Three questionnaire surveys were conducted at buiatrics conferences attended by veterinary practitioners on veterinary dairy herd fertility services (HFS) in countries with a seasonal (Ireland, 47 respondents) and non-seasonal breeding model (The Netherlands, 44 respondents and Portugal, 31 respondents). Of the 122 respondents, 73 (60%) provided a HFS and 49 (40%) did not. The majority (76%) of all practitioners who responded stated that bovine fertility had declined in their practice clients' herds with inadequate cow management, inadequate nutrition and increased milk yield as the most important putative causes. The type of clients who adopted a herd fertility service were deemed more educated than average (70% of respondents), and/or had fertility problems (58%) and/or large herds (53%). The main components of this service were routine postpartum examinations (95% of respondents), fertility records analysis (75%) and ultrasound pregnancy examinations (69%). The number of planned visits per annum varied between an average of four in Ireland, where breeding is seasonal, and 23 in Portugal, where breeding is year-round. The benefits to both the practitioner and their clients from running a HFS were cited as better fertility, financial rewards and job satisfaction. For practitioners who did not run a HFS the main reasons given were no client demand (55%) and lack of fertility records (33%). Better economic evidence to convince clients of the cost-benefit of such a service was seen as a major constraint to adoption of this service by 67% of practitioners.  相似文献   
35.
This study compares diagnostic imaging tools in detecting the parasitic swimbladder nematode Anguillicoloides crassus in Anguilla anguilla (L.) and focuses on ultrasound in an attempt to develop a non‐destructive, field diagnostic test. Ultrasound use could allow the parasite to be diagnosed without decreasing the number of critically endangered European eels through post‐mortem. In the preliminary study, eels were examined with computed radiography, computed tomography, magnetic resonance imaging, 14 MHz high‐end ultrasound and 5 MHz low‐end portable ultrasound, and the results were compared with post‐mortem findings. This ultrasound scanning technique did not produce any promising results. A second batch of eels was examined using the same high‐end and low‐end ultrasounds, but employing a different scanning technique and comparing the results with post‐mortem. This second study, scanning along the midline from below, allowed for the detection of anomalies associated with moderately infected animals. None of the eels used in this study were severely infected; thus, no conclusions can be made regarding the use of ultrasound in those animals. Overall, it was found that none of the techniques were useful in diagnosing mildly infected individuals; therefore, no single diagnostic imaging tool is sensitive enough to replace post‐mortem for definite diagnosis.  相似文献   
36.
Subpolar North Atlantic proxy records document millennial-scale climate variations 500,000 to 340,000 years ago. The cycles have an approximately constant pacing that is similar to that documented for the last glacial cycle. These findings suggest that such climate variations are inherent to the late Pleistocene, regardless of glacial state. Sea surface temperature during the warm peak of Marine Isotope Stage 11 (MIS 11) varied by 0.5 degrees to 1 degrees C, less than the 4 degrees to 4.5 degrees C estimated during times of ice growth and the 3 degrees C estimated for glacial maxima. Coherent deep ocean circulation changes were associated with glacial oscillations in sea surface temperature.  相似文献   
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ABSTRACT

Aims: To investigate the seroprevalence of infection with bovine viral diarrhoea (BVD) virus among 75 beef herds and seroconversion in cattle during early pregnancy, and to determine the practices and opinions of farmers towards BVD control and their association with real and perceived herd serological status.

Methods: Blood samples were collected before mating in 75 beef herds across New Zealand from 15 unvaccinated heifers that had delivered their first calf that season. Serum samples were tested for BVD antibodies using ELISA individually, and after pooling samples for each farm. Animals that were antibody-negative were retested at either pregnancy diagnosis or weaning. Farmers were asked to complete a detailed survey about herd demographics, BVD testing and vaccination practices, and opinions towards national BVD control.

Results: Based on the pooled serum antibody ELISA results, there were 28/75 (37%) negative herds, 15/75 (20%) suspect herds, and 32/75 (43%) positive herds. Of 1,117 animals sampled 729 (65.3%) tested negative for BVD virus antibodies; when retested, 47/589 (8.0%) animals from 13/55 (24%) herds had seroconverted. Among 71 famers providing survey responses 11 (15%) believed their herd was infected with BVD, 24 (34%) were unsure and 36 (51%) did not think their herd was infected. Only 19/71 (18%) farmers had performed any BVD testing within the past 5 years and 50/70 (71%) had not vaccinated any cattle for BVD. Support for national BVD eradication programme was strong in 51/71 (56%) respondents, but the biggest challenge to BVD control was considered to be famer compliance. Compared to farmers who did not think their herd was infected, more farmers who thought BVD was present in their herds had previously tested for BVD, would consider testing all replacement calves, and would support establishing a national BVD database; fewer would consider purchasing BVD tested or vaccinated cattle only.

Conclusions and clinical relevance: Only 15% of the beef farmers in this study believed their herds were infected with BVD virus and few of them had undertaken BVD screening. Nevertheless many were supportive of implementing a national BVD control programme. It is likely that the lack of farmer awareness around BVD and the failure of farmers to recognise the potential impacts in their herds are hindering progress in controlling the disease in New Zealand. There are opportunities for New Zealand veterinarians to be more proactive in helping beef farmers explore BVD management options.  相似文献   
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