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Pregnancy Loss in Dairy Cattle: Relationship of Ultrasound,Blood Pregnancy‐Specific Protein B,Progesterone and Production Variables 下载免费PDF全文
G Gábor JP Kastelic Z Abonyi‐Tóth P Gábor T Endrődi OG Balogh 《Reproduction in domestic animals》2016,51(4):467-473
Objectives were to determine associations between percentage pregnancy loss (PPL) in dairy cattle and: (i) pregnancy diagnosis by ultrasonography; (ii) pregnancy diagnosis by serum pregnancy‐specific protein B (PSPB) concentrations, with or without serum progesterone concentrations; and (iii) production and environmental factors. This study included 149 822 pregnancy diagnoses conducted over 13 years in Holstein‐Friesian cows in Hungarian dairy herds. The following were determined: PPL in cows diagnosed pregnant by transrectal ultrasonography 29–42 days after artificial insemination (AI; n = 11 457); PPL in cows diagnosed pregnant by serum PSPB 29–35 days after AI (n = 138 365); and PPL and its association with serum progesterone concentrations, PSPB and production/environmental variables. The definition of PPL was percentage of cows initially diagnosed pregnant based on ultrasonography or PSPB, but not pregnant when examined by transrectal palpation 60 –70 days after AI. The PPL was lower (p < 0.001) in cows following ultrasonographic vs PSPB diagnosis of pregnancy at 29–35 days (8.1 vs 19.3%, respectively), but was higher in cows following ultrasonographic pregnancy diagnosis on 29–35 vs 36–42 days (8.1 vs 7.1%, respectively, P < 0.05). Furthermore, 72.9% of pregnancies with ultrasound‐detected morphological abnormalities resulted in pregnancy loss. As a subset of PSPB data, a fully quantitative PSPB assay was used for 20 430 samples; PPL in cows with a high PSPB concentration (>1.1 ng/ml) was lowest (15.0%), whereas cows with low concentrations of both PSPB and progesterone (0.6–1.1 and <2 ng/ml, respectively) had the highest PPL (76.3%; p < 0.0001). Furthermore, PPL was higher in cows with advanced parity and with high milk production, when ambient temperatures were high, although body condition score (BCS) had no effect on PPL. Finally, there were no significant associations between serum PSPB and environmental temperatures or number of post‐partum uterine treatments. 相似文献
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This investigation records initial callus development within the graft union and the formation of vascular tissues during the first year's growth of two strains of spur types of ‘Red Delicious’ when combined with the M.26 rootstock. The differing components of stock and scion initiated a meristem at the union of tissues. This was accompanied by swirling of vascular elements continuing from a horizontal into a longitudinal orientation from the original disorganized cambium.Areas within the graft union have been designated as to callus formation, starch-grain accumulation and xylem-ray proliferation by light and scanning electron microscopy. 相似文献
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Encapsulated Stuphylococcus aureus from bovine mastitis 总被引:1,自引:0,他引:1
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Nineteen does (female goats) were dosed with 500,000 oocytes of Hammondia hammondi prior to breeding. At about 90 days of gestation these, and 18 uninoculated does were challenged with 25,000 Toxoplasma gondii oocysts. The 19 H. hammondi--inoculated does produced 26 live and one dead kid (newborn goat). The 18 does not given H. hammondi produced 12 live and 19 dead kids. However, examination of all of the kids by isolation of T. gondii in mice, serology and histology revealed that they were all infected with T. gondii. Thus, while H. hammondi "vaccination" is protective against the deleterious effects of T. gondii on pregnant does, perhaps by reducing the severity of placental lesions, it does not prevent foetal infection. 相似文献
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Liliana Mutascio Federico Vilaplana Grosso Jos Ramos‐Vara Micha Simons 《Veterinary radiology & ultrasound》2019,60(2):E10-E14
A 10‐month‐old German Shepherd Dog presented for evaluation of intermittent vomiting. Abdominal radiographs revealed a marked right cranial mass effect. Initial differentials included abscess/cyst or less likely neoplasia from undetermined origin. On abdominal ultrasound the mass appeared cystic and thin walled. Computed tomography revealed a large cystic lesion originating from the pyloroduodenal junction causing pyloric outflow obstruction. A noncommunicating duodenal duplication cyst was found on exploratory laparotomy and further confirmed with histopathology and immunohistochemistry. Enteric duplication cyst should be considered as a differential in young dogs with gastrointestinal signs and a cystic abdominal mass detected with different imaging modalities. 相似文献