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391.
392.

Objective

To investigate the course‐related and other costs involved in obtaining a veterinary education in Australia and how these costs are met. The study also aimed to identify sociodemographic and course‐related factors associated with increased financial stress.

Methods

Students from seven Australian veterinary schools were surveyed using an online questionnaire. A total of 443 students participated (response rate 17%). Responses to survey items relating to finances, employment and course‐related costs were compared with sociodemographic factors and prior research in the area of student financial stress.

Results

Respondents reported spending a median of A$300 per week on living costs and a median of A$2,000 per year on course‐related expenses. Over half of respondents received the majority of their income from their parents or Youth Allowance (56%). A similar proportion (55%) reported that they needed to work to meet basic living expenses. Circumstances and sociodemographic factors linked to perceived financial stress included requiring additional finances to meet unexpected costs during the course; sourcing additional finances from external loans; an expected tuition debt at graduation over A$40,000; being 22 years or older; working more than 12 hours per week; living costs above A$300 per week; and being female.

Conclusion

The costs involved in obtaining a veterinary education in Australia are high and over half of respondents are reliant on parental or Government income support. Respondents with certain sociodemographic profiles are more prone to financial stress. These findings may have implications for the psychological health, diversity and career plans of veterinary students in Australia.  相似文献   
393.
AIM: To conduct an epidemiological investigation of an idiopathic myopathy, known as “Go Slow” (GSM), which was initially recognised in dogs used for pig hunting. A secondary aim was to describe the hunting activities, diet and health of dogs used for pig hunting in New Zealand.

METHODS: A retrospective cohort study was conducted between June 2014–June 2017. Cases of GSM in dogs were diagnosed by veterinarians using a combination of clinical history, physical examination findings, serum biochemistry and/or skeletal muscle histology. A telephone interview was conducted with the owner or primary veterinarian to provide information regarding the dog’s diet and exercise over the 7 days preceding the onset of clinical signs. In August 2015, a separate online survey of owners of dogs used for pig hunting was conducted to characterise the normal hunting activities, diet and health of these dogs.

RESULTS: A total of 86 cases of GSM were recruited, of which 58 (67%) were pig hunting dogs, 16 (19%) pet dogs and 12 (14%) working farm dogs. Cases were most commonly reported in the upper North Island, and 65 (76 (95% CI=67–85)%) were from the Northland region. Processed commercial dog food had been fed to 93 (95% CI=88–98)% of affected dogs. Ingestion of raw, frozen or cooked wild pig in the preceding week was reported for 76 (88 (95% CI=82–95)%) dogs with the myopathy. In the survey of owners of healthy pig hunting dogs, 203 eligible responses were received; pig hunting was reported to most commonly occur in Northland (20.2%), Waikato (22.3%) and Bay of Plenty (23.2%) regions. Commercial dog food was fed to 172 (85 (95% CI=80–90)%) of the dogs included in this survey, and 55 (27 (95% CI=20–33)%) had eaten wild pig in the preceding week. The most common reported health problem in pig hunting dogs was traumatic wounds.

CONCLUSIONS: Cases of GSM were most commonly recognised in dogs used for pig hunting, but also occurred in pet and working farm dogs. The disease was most frequently reported in the upper North Island of New Zealand and ingestion of wild pig was a consistent feature in cases of this myopathy.

CLINICAL RELEVANCE: To minimise the risk of dogs developing this myopathy, it would seem prudent to avoid feeding any tissues from wild pigs to dogs in areas where the disease is known to occur.  相似文献   

394.
This study determined the effects of feed supplementation during the postpartum period on the weight gain, milk yield, blood profiles and reproductive performance of Sanga and Friesian-Sanga cows grazing on natural pasture. 20 Sanga and 20 Friesian-Sanga cows were randomly allocated either to serve as a control on grazing only or to be supplemented with 2.5 kg of concentrate a day for 10 weeks during the dry season. Each week, all cows were weighed and scored for body condition. Partial milk yield of cows was determined daily. Plasma concentrations of blood metabolites were assessed fortnightly from weeks 1 to 10 postpartum. Resumption of postpartum ovarian activity was determined by measuring progesterone concentration in the plasma from weeks 1 to 10. Supplemented cows had a better body condition score (6.2 versus 5.8; P?<?0.05) and higher partial milk yield (1.94 versus 1.55 L/day; P?<?0.01) than non-supplemented cows. Sanga cows had a better body condition score (6.2 versus 5.8; P?<?0.05) but lower milk yield (1.58 versus 1.92 L/day; P?<?0.01) than the Friesian-Sanga crossbreds. Total protein (P?<?0.05) and albumin (P?<?0.01) concentrations were higher in the supplemented than in the non-supplemented cows. Sanga cows recorded higher globulin (P?<?0.05) and total cholesterol (P?<?0.01) but lower albumin (P?<?0.01) concentrations than Friesian-Sanga crossbred cows. Feed supplementation did not affect (P?<?0.05) the interval from calving to resumption of ovarian activity, and the days to resumption of ovarian activity in the Sanga and Friesian-Sanga cows were also similar (P?>?0.05). The results demonstrate the beneficial effects of feed supplementation in terms of improved body condition and metabolic status and increased milk yield.  相似文献   
395.
396.
Spermatogonial stem cells (SSC) have important applications in domestic animal reproduction and advanced biotechnologies. Because differential plating is one of the most common methods used for SSC enrichment, the goal of this study was to compare three differential plating methods for the enrichment of bovine SSC. To achieve this goal, testicular parenchyma from pre‐pubertal calves was minced and single cells were obtained after two enzymatic digestions. We compared three coating methods for differential plating: laminin (20 ng/ml), BSA (0.05 mg/ml) and PBS. Cells were incubated at 37°C, 5% CO2 in air for 15 min onto laminin‐coated dishes or 2 h onto BSA‐ or PBS‐coated dishes. Cell viability was assessed by trypan blue exclusion method. Recovered cells were analysed for the expression of SSC molecular markers by quantitative RT‐PCR (GFRA1, CXCR4, ITGA6, THY1) and flow cytometry (GFRA1, CXCR4 and ITGA6). Cells at time 0, adherent cells on laminin and non‐adherent cells from BSA and PBS groups had the same cell viability (p = 0.0655). GFRA1, CXCR4 and THY1 relative gene expression was higher (p = 0.0402, p = 0.0007, p = 0.0117, respectively) for non‐adherent cells selected in PBS group. Flow cytometry analysis revealed that the presence of GFRA‐positive (GFRA+) cells was higher in non‐adherent cells from BSA and PBS groups (p < 0.001). However, laminin‐adherent cells had higher number of ITGA6+ cells (p < 0.001) and lower presence of CXCR4+ cells (p = 0.0012). In conclusion, differential plating is an effective method for the enrichment of bovine undifferentiated spermatogonia and higher expression of SSC markers is obtained without laminin or BSA coating.  相似文献   
397.
The aims of this study were to assess the effects of the sex‐sorting process on post‐thaw sperm quality as well as on induced oxidative stress damage (H2O2 0 mm  = H000; H2O2 50 mm  = H050; H2O2 100 mm  = H100) and the protective action of reduced glutathione (GSH) and Trolox, when comparing sorted (BSS) and non‐sorted (NS) red deer spermatozoa incubated at 37°C. Sperm samples from three stags were collected by electroejaculation and frozen. Immediately after thawing, sperm motility was higher (p < 0.05) for NS (59% ± 3.3) than BSS (36.9% ± 5.8) sperm. Furthermore, the percentage of apoptotic sperm was higher (p < 0.05) for BSS (21.6% ± 5.0) than NS sperm (14.6% ± 1.2). The presence of H2O2 increased DNA damage in NS (H000 = 4.1% ± 0.9; H050 = 9.3% ± 0.7; and H100 = 10.9% ± 2.3), but not in BSS sperm. However, in the presence of oxidant, GSH addition improved (p < 0.05) sperm motility in both groups of sperm samples as compared to their controls (NS: 44.5 ± 4.8 vs 21.1 ± 3.9 and BSS: 33.3 ± 8.1 vs 8.9 ± 1.8). These results demonstrate that the sperm‐sorting process induces sublethal effects, albeit selecting a sperm population with a chromatin more resistant to oxidative stress than that in non‐sorted sperm. Moreover, addition of GSH at 1 mm may be a good choice for maintaining the quality of stressed sperm samples, unlike Trolox, which inhibited sperm motility.  相似文献   
398.
Antimicrobial use and resistance in animal and food production are of concern to public health. The primary aims of this study were to determine the frequency of resistance to 12 antimicrobials in Escherichia coli isolates from 39 pig farms and to identify patterns of antimicrobial use on these farms. Further aims were to determine whether a categorization of farms based on the duration of in‐feed antimicrobial use (long‐term versus short‐term) could predict the occurrence of resistance on these farms and to identify the usage of specific antimicrobial drugs associated with the occurrence of resistance. Escherichia coli were isolated from all production stages on these farms; susceptibility testing was carried out against a panel of antimicrobials. Antimicrobial prescribing data were collected, and farms were categorized as long term or short term based on these. Resistance frequencies and antimicrobial use were tabulated. Logistic regression models of resistance to each antimicrobial were constructed with stage of production, duration of antimicrobial use and the use of 5 antimicrobial classes included as explanatory variables in each model. The greatest frequencies of resistance were observed to tetracycline, trimethoprim/sulphamethoxazole and streptomycin with the highest levels of resistance observed in isolates from first‐stage weaned pigs. Differences in the types of antimicrobial drugs used were noted between long‐term and short‐term use farms. Categorization of farms as long‐ or short‐term use was sufficient to predict the likely occurrence of resistance to 3 antimicrobial classes and could provide an aid in the control of resistance in the food chain. Stage of production was a significant predictor variable in all models of resistance constructed and did not solely reflect antimicrobial use at each stage. Cross‐selection and co‐selection for resistance was evident in the models constructed, and the use of trimethoprim/sulphonamide drugs in particular was associated with the occurrence of resistance to other antimicrobials.  相似文献   
399.
400.
Today's livestock diversity originated from the wild ancestor species and was subsequently shaped through the processes of mutation, genetic drift, and natural and human selection. Only a subset of the diversity present in the ancestral species survives in the domestic counterparts. A 2007 report released by UN Food and Agriculture Organization ' The State of the World's Animal Genetic Resources ', compiled from surveys conducted in 169 countries, found that nearly 70% of the world's remaining livestock breeds live in developing countries. The UN report was presented to more than 300 policy makers, scientists, breeders, and livestock keepers at the First International Technical Conference on Animal Genetic Resources, held in September 2007 in Interlaken, Switzerland. The conference aims were to adopt a global plan of action for conserving animal genetic resources as its main outcome. In this paper, the current and potential contributions of reproductive and molecular biotechnology are considered as tools of conserving rare breeds of livestock.  相似文献   
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