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AIMS: To determine if abdominal insufflation with medical air will improve oxygenation and ventilation parameters when compared to insufflation with CO2 in xylazine-sedated sheep undergoing laparoscopic artificial insemination (AI).

METHODS: Forty-seven sheep underwent oestrus synchronisation and were fasted for 24 hours prior to laparoscopic AI. Each animal was randomised to receive either CO2 or medical air for abdominal insufflation. An auricular arterial catheter was placed and utilised for serial blood sampling. Respiratory rates (RR) and arterial blood samples were collected at baseline, after xylazine (0.1?mg/kg I/V) sedation, 2 minutes after Trendelenburg positioning, 5 minutes after abdominal insufflation, and 10 minutes after being returned to a standing position. Blood samples were collected in heparinised syringes, stored on ice, and analysed for arterial pH, partial pressure of arterial O2 (PaO2), and CO2 (PaCO2). The number of ewes conceiving to AI was also determined.

RESULTS: Repeated measures ANOVA demonstrated temporal effects on RR, PaO2, PaCO2 and arterial pH during the laparoscopic AI procedure (p<0.001), but no difference between insufflation groups (p>0.01). No sheep experienced hypercapnia (PaCO2>50?mmHg) or acidaemia (pH<7.35). Hypoxaemia (PaO2<70?mmHg) was diagnosed during the procedure in 14/22 (64%) ewes in the CO2 group compared with 8/23 (35%) ewes in the medical air group (p=0.053). Overall, 15/20 (75%) ewes in the CO2 group conceived to AI compared with 16/22 (72.7%) in the medical air group (p=0.867).

CONCLUSIONS AND CLINICAL RELEVANCE: There were no statistical or clinical differences in RR, PaO2, PaCO2, pH, or conception to AI when comparing the effects of CO2 and medical air as abdominal insufflation gases. None of the sheep experienced hypercapnia or acidaemic, yet 42% (19/45) of sheep developed clinical hypoxaemia, with a higher percentage of ewes in the CO2 group developing hypoxaemia than in the medical air group. Based on the overall analysis, medical air could be utilised as a comparable alternative for abdominal insufflation during laparoscopic AI procedures.  相似文献   
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Upland, intermediate and lowland sites in northeastern Ontario were planted between May 28 and June 8 with three types of black spruce (Picea mariana (Mill.) BSP) nursery stock: (1) spring-lifted, 1.5 + 1.5 bareroot plants (BR); (2) 24-week-old, winter-sown, container stock (CWS); and (3) spring-sown, overwintered, container stock (CO). At the beginning of the growing season, the BR stock had the lowest xylem pressure potentials (Psi(x)), stomatal conductances (g(wv)), and net photosynthetic (P(n)) rates. By the end of the growing season, the BR stock still had lower g(wv)s than the container stock types, but had higher shoot Psi(x) values. In August, the turgor loss points for the BR, CO and CWS stock types were -2.8, -1.93 and -1.6 MPa, respectively, while the minimum observed shoot Psi(x) values were -1.4, -1.7 and -1.9 MPa, respectively. The BR stock produced the greatest dry weight of new shoots and unsuberized roots. No new shoots were produced by the CWS stock, but they produced a greater dry weight of unsuberized roots than the CO stock. As a percent of the dry weight of suberized roots, the greatest production of unsuberized roots was by the CWS stock, the least by the BR trees.  相似文献   
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Abstract Extract A 15-year-old pony mare developed firm irregular bony swellings on all four legs. These were most severe around the carpal and fetlock joints of the forelegs, restricting both flexion and extension. Over about 6 months the horse had periodic bouts of coughing. She showed moderate weight loss and a depressed demeanour.  相似文献   
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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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Veterinary students completed an online survey regarding personal and academic concerns they experienced during their first year of veterinary school. Quantitative results showed a high degree of stress and anxiety among the study participants as well as concerns about time management and study skills. Quantitative analysis using chi-square tests revealed significant associations between concerns about study skills and the independent variables of relationship status and time since obtaining an undergraduate degree. Results of a thematic analysis undertaken with the qualitative data provide further insight into first-year experiences, indicating concerns about the intensity of the program and especially about time commitment, the amount of information students were expected to learn, and the amount of material they were expected to memorize. Another theme revealed that students did not feel academically prepared for some of their first-year courses, which led to their not liking those courses for which they lacked appropriate groundwork. Other themes highlighted the students' desire for more clinically relevant experiences during their first year as well as surprises regarding the maturity level of classmates and the level of support offered by professors. Given the results of this study, suggestions for counselors and others who work with veterinary students are provided.  相似文献   
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