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31.
A 12-week-old female alpaca cria weighing 10 kg presented with a 2-month history of left hindlimb lameness associated with osteomyelitis and sequestration of the shaft and wing of the left ilium. The affected segment of the ilium was surgically removed. Bacteriological culture revealed a small number of mixed aerobic and anaerobic bacteria. The cria recovered well, was discharged from the hospital 8 days after surgery and was paddock sound without complications 8 months later. Osteomyelitis and sequestration of long bones has been reported in alpacas, but further investigation is necessary to define the prevalence and pathogenesis and to develop specific recommendations for prevention and treatment.  相似文献   
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Obesity is a serious international health problem that increases the risk of several common diseases. The genetic factors predisposing to obesity are poorly understood. A genome-wide search for type 2 diabetes-susceptibility genes identified a common variant in the FTO (fat mass and obesity associated) gene that predisposes to diabetes through an effect on body mass index (BMI). An additive association of the variant with BMI was replicated in 13 cohorts with 38,759 participants. The 16% of adults who are homozygous for the risk allele weighed about 3 kilograms more and had 1.67-fold increased odds of obesity when compared with those not inheriting a risk allele. This association was observed from age 7 years upward and reflects a specific increase in fat mass.  相似文献   
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The purpose of this study was to validate a technique for simultaneous evaluation of the plasma, acrosomal and mitochondrial membranes in boar spermatozoa, using an association of fluorescent probes: Propidium iodide (PI), fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA) and JC-1. Three ejaculates from each of four different boars, all showing motility >or=80% and abnormal morphology 相似文献   
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Soon after ovulation, the newly formed corpus luteum (CL) starts secreting progesterone (P(4)), necessary for implantation. The CL, an ovarian transient endocrine organ, undergoes growth and regression throughout its life span. The objective of this study was to evaluate if caspase-3 mediates cell death in the equine cyclic luteal structures and relate it to luteal endocrine function. Blood and luteal tissue were collected during the breeding season after slaughter from 38 randomly assigned cycling mares. Luteal tissues were classified as corpora haemorrhagica (CH; n = 7); mid luteal phase corpora lutea (Mid-CL; n = 17); late or regressing corpora lutea (Late-CL; n = 9) and corpora albicans (CA; n = 5). Plasma P(4) concentration, determined by radioimmunoassay, showed a significant increase from CH to Mid-CL (p < 0.001), followed by a decrease to Late-CL (p < 0.001) and CA (p < 0.001). Caspase-3 processing and poly (ADP) ribose polymerase (PARP) degradation were assessed by western blotting. Active caspase-3 was twofold increased in Mid-CL, Late-CL and CA as compared with CH (p < 0.05). Immunocytochemistry also showed a significant increase in caspase-3 expression in large luteal cells in all structures when compared with CH (p < 0.05). Consistently, the endogenous caspase-3 substrate, PARP, was markedly degraded from CH to CA (p < 0.05). In fact, the ratio of full-length to degraded PARP showed a significant decrease from CH to Mid-CL, Late-CL and CA (p < 0.05). Finally, the decrease in P(4) from Mid- to Late-CL coincided with no further increases in apoptosis. In conclusion, these results suggest that the effector caspase-3 of apoptosis, might play an important role during luteal tissue involution in the mare, even though its relationship with P(4) remains to be elucidated.  相似文献   
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The objective of this study was to examine the follicular dynamics of five-eighths Girolando cows by observing the number of follicular development waves, days of emergence of those waves, diameters of the dominant and largest subordinate follicles and the processes of follicular selection and dominance. Ovarian follicle dynamics were monitored for 24 oestrous cycles in 12 cows, of 4 to 10 years of age, presenting regular oestrous cycles and with body scores between 3 and 4. Ovaries were observed daily for two consecutive oestrous cycles and follicles were measured with ultrasonographic equipment. The dominant follicle was considered to be that which presented a diameter ≥ 10 mm for three consecutive days and on the day of wave emergence, when a group of follicles measuring 3–5 mm in diameter would appear. Of the 24 cycles monitored, 62.5% presented two waves of follicular development and 37.5% presented three waves. The cycles presenting two waves had an average duration of 20 days, with the emergence of the waves on days 1 and 9, whereas the cycles presenting three waves had an average duration of 22 days, with emergences on days 1, 10 and 16. For cycles with two waves, both the first and second dominant follicles reached an average size of 13.8 mm, with the first regressing on day 10 and the second ovulating around day 20. For cycles with three waves, the dominant follicles of the first and second waves reached maximum diameters of 11.8 and 12 mm, respectively, with the first regressing on day 11 and the second regressing on day 17. The third dominant follicle reached a maximum diameter of 12.4 mm on day 20, and ovulated on day 22. These results lead to the conclusion that the follicular dynamics of five-eighths Girolando cows are characterized by the presence of two to three waves of follicular growth.  相似文献   
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Lizards have been reported as important pollinators on several oceanic islands. Here we evaluate the potential role of Galápagos lava lizards (Microlophus spp.) as pollinators across their radiation. Over 3 years, we sampled pollen transport by 9 lava lizard species on the 10 islands where they are present, including 7 single‐island endemics. Overall, only 25 of 296 individuals sampled (8.4%) transported pollen of 10 plant species, the most common being Prosopis juliflora, Exodeconus miersii, Sesuvium sp. and Cordia leucophlyctis. At least 8 of these plant species were native, and none were confirmed as introduced to the archipelago. Despite the low overall proportion of individuals carrying pollen, this was observed in 7 of the nine lizard species, and on 8 of the ten main islands (Española, Fernandina, Floreana, Isabela, Marchena, Pinta, Santa Cruz and Santiago), suggesting that this is a widespread interaction. The results reported here support the potential role of lava lizards as pollinators across their radiation, although they may represent a relatively modest contribution when compared with birds and insects. However, we cannot discard that lizards may be ecologically significant for particular plant species and ecosystems given the specific climatic condition and functional diversity of each island.  相似文献   
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