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991.
The Lanyu pig is an indigenous breed from the Lanyu Islet, which is southeast of Taiwan. Two herds of Lanyu pigs were introduced from the Lanyu Islet into Taiwan in 1975 and 1980. The current population of conserved Lanyu pigs consists of only 44 animals with unknown genetic lineage. The Lanyu pig possesses a distinct maternal genetic lineage remote from Asian and European pigs. The present study aimed to understand the phylogenetic relationship among conserved Lanyu, Asian, and European type pigs based on the cytochrome b coding gene, to ascertain the maternal lineage and genetic diversity within the conserved Lanyu pigs, and to address whether genetic introgression from exotic or Formosan wild pigs had occurred in the conserved Lanyu pigs. Entire mitochondrial genomes of both types of Lanyu pig comprised 2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes. Only 2 haplotypes of the mitochondrial DNA (mtDNA) control region and cytochrome b were identified in the conserved Lanyu pig herds. When maximum likelihood trees were constructed, the Type I Lanyu mitochondrial genes formed a unique clade with a large pairwise distance of both cytochrome b and the control region from Asian and European type breeds, Formosan wild pigs, and exotic breeds. Significant loss of genetic diversity of mtDNA within the conserved Lanyu pigs was demonstrated by low haplotype and nucleotide diversities, supported by Fu and Li's D* neutrality test (1.44055; P < 0.05). The mtDNA control region sequences of extant pigs in the Lanyu Islet, however, showed high haplotype and nucleotide diversity, and clustered with exotic pigs. These results indicate no maternal lineage mtD-NA gene introgression from Formosan wild pigs and introduced exotic pigs to conserved Type I Lanyu pigs, and a severe loss of heterozygosity of mtDNA in conserved Lanyu pigs. The remaining extant pigs on the Lanyu Islet have been introgressed with exotic breeds. Strategies for future conservation of native Lanyu pigs are now even more urgent and important.  相似文献   
992.
A 2-yr study was conducted to confirm that managed pastures can provide Holstein steers adequate P to meet their daily requirement. Treatments offered were trace mineralized salt with or without additional P. In the first year, 80 Holstein steers (248 kg of BW) were assigned to 4 grazing groups. Treatments were trace mineralized salt only or a 67:33 mixture of trace mineralized salt and dicalcium phosphate. Steers rotationally grazed a cool-season grass/legume mixture for 137 d. Fecal bags were placed on 3 steers from each grazing group (n = 12) over a 4-d period for estimation of forage DMI and forage contribution to daily P intake twice during the grazing season. Analyzed pasture samples contained 3.28 mg of P/g of DM. During the second year, 72 Holstein steers (297 kg of BW) were blocked into 2 BW groups and subsequently assigned to 1 of 4 pasture groups. Steers rotationally grazed the same forage base as the first year for 126 d. Pasture samples contained 3.27 mg of P/g of DM. No significant differences (P > 0.10) were detected for BW, ADG, or free-choice supplemental mineral intake. Forage provided 126% of the recommended NRC P requirement. Thus, supplemental phosphorous was not required for Holstein steers grazing mixed, cool-season, grass/legume pastures.  相似文献   
993.
Reasons for performing study: Rigorous evaluation of practicable methods for the objective assessment of foot conformation has not been performed. Objectives: To assess the practicability, precision and accuracy of the process of obtaining measurements of horses' feet using photography and image processing software. Methods: Precision study: Lateral photographs of horses' feet were obtained twice by 2 veterinary surgeons (image acquisition ‐ IAc). Photographs were analysed by 2 masked veterinary surgeons on 2 occasions (image analysis ‐ IAn). Measurements were compared within and between operators for self and non‐self acquired photographs. Agreement indices (AIs) and 95% limits of agreement (LOA) were calculated for the IAn process alone and for the combined IAc + IAn processes. Accuracy study: Measurements obtained from lateral photographs were compared with those obtained from lateromedial radiographs. AIs and 95% LOA were calculated for each measurement. Results: Precision study: Mean intra‐ and interoperator AIs for the IAn process alone were ≥0.90 while those for the combined IAc + IAn processes were ≥0.89 for all measurements. Similar mean AIs and 95% LOA were calculated regardless of image origin. The 95% LOA for hoof angle, heel height/toe height% and coronary band angle for all comparisons were within target values. Accuracy study: Mean AIs were ≥0.89 for all measurements. The 95% LOA for heel height/toe height% and coronary band angle were within target values. Conclusions: Excellent precision was identified within and between operators regardless of image origin. High levels of accuracy were also identified, especially for heel height/toe height% and coronary band angle, indicating that photography and radiography may be used interchangeably. Potential relevance: Acquisition and analysis of photographic images is an appropriate method for the objective measurement of foot conformation, both in clinical and research settings.  相似文献   
994.
Hay samples from 29 horse farms in Southern Upper Bavaria and 31 horse farms in Switzerland were taken and analysed for minerals such as calcium, magnesium, phosphorus and potassium. The content of herbs and legumes in the hay was determined and the Weende analysis was performed. Comparison between Bavaria and Switzerland resulted in comparable calcium contents of approximately 4 g Ca/kg dry matter (DM) in grass hay. Hay with more than 10% of herbs and legumes found only in Switzerland showed higher Ca contents of >7 g Ca/kg DM in hay. The mineral contents of phosphorus and potassium were lower in hay from Switzerland (P: 1.8 ± 0.7 g/kg DM, K: 15.4 ± 5.1 g/kg DM) than from Bavaria (P: 3.8 ± 0.6 g/kg DM, K: 20.0 ± 6.0 DM), whereas the magnesium content of the hay showed no difference between the regions (∼1.5 g Mg/kg DM). Very late first grass hay cuts showed low magnesium and calcium (<4 g/kg DM) contents. Further minerals in the hay for horses differed from those in dairy cattle in the same region. Fertilization showed only small effects on the mineral contents of the hay produced for horses. Therefore, in calculation of ration and production of supplements for horses, these differences should be taken into account.  相似文献   
995.
Genetic parameters of piglet survival traits and birth weight were estimated on the first generation data of a selection experiment aimed at improving piglet survival using a multiple trait linear and threshold model. Data on 5293 piglets for survival at birth, at day one after birth and during the entire nursing period, as well as individual birth weight and litter size, were recorded in an outdoor production system. Genetic effects of piglet survival traits and birth weight were estimated based on threshold and Gaussian models, respectively, using a Bayesian approach. The statistical model included as fixed effects selection group, parity, gender, fostering, gestation length and month of farrowing and, alternatively, an adjustment for litter size. Direct genetic effects (i.e. the piglet's genetic potential) for piglet survival and birth weight were estimated separately, whereas maternal genetic and environmental effects could only be estimated for the given data structure in a combined litter effect. Posterior means of heritabilities for direct genetic effects of survival at birth, at first day after birth and the entire nursing period, as well as birth weight, were 0.08, 0.07, 0.08 and 0.20, respectively. Genetic correlations among survival traits were in the range of 0.29 to 0.40 and indicate that these traits were mainly attributable to different genetic effects. Genetic correlations between direct effects of survival traits and birth weight ranged between 0.18 and 0.23 and were reduced when weights of stillborn piglets were omitted in the analysis or the traits were adjusted for litter size. The magnitudes of direct genetic effects of survival traits are substantially higher than estimates in the literature, which may indicate that these traits have a higher genetic influence under outdoor conditions. The use of birth weight in the multiple trait estimation provided important information for the estimation of survival traits due to its favourable genetic correlations with survival, its high heritability and its high information content as a continuously measured trait.  相似文献   
996.
Most studies on lactation curves only consider milk yield and describe a standard lactation curve of dairy cows, showing a peak or maximum daily yield occurring between 4 and 8 weeks after calving, followed by a daily decrease in milk yield until the cow is dried off. Wood's model is a widely used lactation curve function. Wood's model was fitted to test-day records of 95,405 lactations of parities lower than 5. Milk traits were milk yield (MY), fat percentage (F%), protein percentage (P%), fat yield (FY) and protein yield (PY), and the lactation curve was individually considered as a cluster of five linked curves. Milk trait and parity influence the goodness of fit of Wood's model. In 19.3% of the lactations, the shape of the MY, FY and PY curves follows the standard lactation curve while F% and P% have the reversed standard shape. The initial phase of lactation with the FY and PY curves contributes to the high variability of shapes.  相似文献   
997.
Human patients with atopic dermatitis (AD) commonly exhibit IgE reactivity to cutaneous self-antigens. The presence of serum IgE autoantibodies appears to correlate with disease severity, and it is suspected to reflect or contribute to tissue damage. The objective of this study was to determine whether IgE autoantibodies specific for cutaneous antigens could be detected in the serum of dogs with AD. Serum was collected from 19 dogs with untreated moderate to severe AD and four specific-pathogen free (SPF) dogs. Indirect immunofluorescence was performed using normal canine skin collected at four different locations (concave ear, nose, medial thigh and lateral thorax), while Western immunoblotting was done using normal canine ear pinna epidermal and dermal extracts and reducing conditions. In both methods, IgE was detected using a monoclonal antibody specific for heat stable epitopes of canine IgE. At 1:10 dilution, specific IgE autoantibodies against cutaneous autoantigens were not detected, with either method, in AD and SPF canine sera. Either IgE autoreactivity is not associated with moderate to severe AD in dogs, or the methods employed herein were not sensitive enough to permit IgE autoantibody detection.  相似文献   
998.
999.
BACKGROUND: Urea and creatinine are the most frequently used indirect markers in plasma and serum of glomerular filtration rate in dogs. Both have been shown to lack sensitivity but their diagnostic efficiency for the diagnosis of kidney disease has been minimally investigated. OBJECTIVE: The purpose of this retrospective study was to investigate the influence of possible factors of variation on both analytes and to determine whether specific decision rules should be drawn up for subpopulations of dogs. METHODS: The results of urea and creatinine measurements, breed, sex, age, and health status (healthy, renal disease, or nonrenal disease) of 3822 dogs were collected from the archives of 5 veterinary clinics. Data were analyzed with univariate and multivariate decision rules with and without adjustment. RESULTS: There were significant effects and interactions of almost all of the sources of variation. Slight improvements in diagnostic efficiency were obtained by adjusting the decision rules to these sources of variations. Univariate decision rules gave approximately the same diagnostic efficiency for urea and creatinine concentrations, with sensitivity and specificity in the range of 70% and 90%, respectively, using the upper limit of the reference interval as the threshold value. Multivariate decision rules provided only minor improvements in diagnostic efficiency. CONCLUSION: Simultaneous measurement of both urea and creatinine is of limited diagnostic value over the analysis of a single variable. Creatinine is the preferred analyte as it is affected by fewer extrarenal factors of variation.  相似文献   
1000.
In January 2007, six veterinary students became infected with Cryptosporidium species, and records indicated that another student had been diagnosed in November 2006. It was established that the seven students had worked with cattle from the same farm. Microbiological tests indicated that they were infected with Cryptosporidium parvum. Subtyping by sequence analysis indicated a common source of infection for five of the students, but there was insufficient material to type the other two samples. Investigations indicated that the outbreak was caused by a lapse in hygiene, particularly handwashing, on a farm with enzootic C parvum in calves.  相似文献   
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