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991.
R Manjarin JC Dominguez MJ Castro DJ Sprecher G Cassar RM Friendship RN Kirkwood 《Reproduction in domestic animals》2009,44(3):432-434
To ensure sufficient numbers of pregnant females, particularly at hotter times of the year, hormonal induction of gilt oestrus may be necessary. However, the gilt oestrus and ovulation responses to gonadotrophin treatment have often proven unpredictable. The objective of this study was to examine possible reasons for this unpredictability. Prepubertal gilts (approximately 150 days of age, n = 63) were assigned to one of three treatments: injection of 300 IU hCG (n = 15); pre-treatment with 100 mg FSH in polyvinylpyrrolidinone administered as 2 × 50 mg injections 24 h apart, followed by 600 IU eCG at 24 h after the second FSH injection (n = 23); or FSH pre-treatment as above followed by 300 IU hCG at 24 h after the second FSH injection (n = 25). To facilitate oestrus detection, gilts were exposed to a mature boar for 15 min daily for 7 days. Blood samples were obtained on the day of eCG or hCG injection and again 10 days later and gilt ovulation responses determined based on elevated progesterone concentrations. The oestrus responses by 7 days were 6.7%, 17.5% and 64.0% for gilts treated with hCG, FSH + eCG and FSH + hCG, respectively (p < 0.001). The oestrous gilt receiving hCG alone and one oestrous FSH + hCG gilt did not ovulate, all other oestrous gilts ovulated. A further two anoestrous FSH + eCG-treated gilts ovulated. These data suggest that FSH pre-treatment facilitated the development of ovarian follicles to the point where they became responsive to hCG, but had little effect on the response to eCG. 相似文献
992.
Comparison of transcutaneous ultrasound over the right flank with transrectal ultrasound for pregnancy diagnosis in the dairy cow 总被引:1,自引:1,他引:0
JC Hunnam TJ Parkinson N Lopez-Villalobos S McDougall 《Australian veterinary journal》2009,87(8):318-322
Objective Evaluate the sensitivity and specificity of transrectal ultrasound and transcutaneous ultrasonography across the right flank between days 31 and 196 of pregnancy in the dairy cow.
Procedure Pregnancy status and stage of gestation at date of pregnancy diagnosis by transcutaneous and transrectal ultrasonography were determined for 1570 dairy cattle. Sensitivity and specificity values and probabilities of a correct diagnosis for both techniques were determined and compared. Possible effects of gestational age, herd, method of transcutaneous ultrasound diagnosis, cow age, cow and bull breed, and calf sex on the determination of a correct diagnosis of pregnancy status were evaluated for both techniques.
Results The overall sensitivity and probability of a correct diagnosis of pregnancy status from days 31 to 196 of gestation were significantly higher when using transrectal ultrasound relative to transcutaneous ultrasound over the right flank. However, the sensitivity of transcutaneous ultrasound changed over the course of pregnancy: it was low (7–8%) before day 84, increased to 89% between days 141 and 154, and was close to 100% thereafter. The specificity of both methods did not differ significantly. Herd and gestational age at date of pregnancy diagnosis were significantly associated with making a correct test result using transcutaneous ultrasound, although only the latter predictor was significantly associated with making a correct test result using transrectal ultrasound.
Conclusion Transcutaneous ultrasound can not be recommended as an accurate method for early pregnancy diagnosis in the dairy cow, particularly on a whole-herd basis. However, if pregnancy testing is undertaken in mid to late gestation, this technique could provide an accurate and rapid alternative to transrectal ultrasound or manual palpation per rectum. 相似文献
Procedure Pregnancy status and stage of gestation at date of pregnancy diagnosis by transcutaneous and transrectal ultrasonography were determined for 1570 dairy cattle. Sensitivity and specificity values and probabilities of a correct diagnosis for both techniques were determined and compared. Possible effects of gestational age, herd, method of transcutaneous ultrasound diagnosis, cow age, cow and bull breed, and calf sex on the determination of a correct diagnosis of pregnancy status were evaluated for both techniques.
Results The overall sensitivity and probability of a correct diagnosis of pregnancy status from days 31 to 196 of gestation were significantly higher when using transrectal ultrasound relative to transcutaneous ultrasound over the right flank. However, the sensitivity of transcutaneous ultrasound changed over the course of pregnancy: it was low (7–8%) before day 84, increased to 89% between days 141 and 154, and was close to 100% thereafter. The specificity of both methods did not differ significantly. Herd and gestational age at date of pregnancy diagnosis were significantly associated with making a correct test result using transcutaneous ultrasound, although only the latter predictor was significantly associated with making a correct test result using transrectal ultrasound.
Conclusion Transcutaneous ultrasound can not be recommended as an accurate method for early pregnancy diagnosis in the dairy cow, particularly on a whole-herd basis. However, if pregnancy testing is undertaken in mid to late gestation, this technique could provide an accurate and rapid alternative to transrectal ultrasound or manual palpation per rectum. 相似文献
993.
JC Hunnam TJ Parkinson N Lopez-Villalobos S McDougall 《Australian veterinary journal》2009,87(9):379-383
Objective To determine bovine fetal characteristics significantly associated with increasing gestational age as measured via transcutaneous ultrasonography over the right flank.
Methods The length of gestation at date of pregnancy diagnosis via transcutaneous and transrectal ultrasonography was determined for 224 dairy cattle by estimation from subsequent calving dates. A separate dataset was created for each measurable fetal characteristic (i.e. thoracic diameter, abdominal diameter, umbilical diameter, placentome length and placentome height) and risk factors significantly associated with gestational age at pregnancy diagnosis within each dataset, including the fetal characteristic, were identified.
Results Abdominal diameter was the most frequently observed fetal characteristic and thoracic diameter was the least. Gestational age at pregnancy diagnosis (d) was significantly associated with fetal thoracic diameter (P < 0.01), abdominal diameter (P < 0.01) and umbilical diameter (P = 0.02) when measured via transcutaneous ultrasound. Within each model, sire breed, dam breed, dam age and/or calf sex were also significantly associated with gestational age. Gestational age at pregnancy diagnosis was not significantly associated with either placentome height or length (P > 0.05).
Conclusion Fetal thoracic diameter, abdominal diameter and umbilical diameter were found to be significantly associated with gestational age between approximate days 73 to 190 of gestation. Transcutaneous ultrasonography may prove a useful method of estimating gestational age in the absence of accurate breeding records. 相似文献
Methods The length of gestation at date of pregnancy diagnosis via transcutaneous and transrectal ultrasonography was determined for 224 dairy cattle by estimation from subsequent calving dates. A separate dataset was created for each measurable fetal characteristic (i.e. thoracic diameter, abdominal diameter, umbilical diameter, placentome length and placentome height) and risk factors significantly associated with gestational age at pregnancy diagnosis within each dataset, including the fetal characteristic, were identified.
Results Abdominal diameter was the most frequently observed fetal characteristic and thoracic diameter was the least. Gestational age at pregnancy diagnosis (d) was significantly associated with fetal thoracic diameter (P < 0.01), abdominal diameter (P < 0.01) and umbilical diameter (P = 0.02) when measured via transcutaneous ultrasound. Within each model, sire breed, dam breed, dam age and/or calf sex were also significantly associated with gestational age. Gestational age at pregnancy diagnosis was not significantly associated with either placentome height or length (P > 0.05).
Conclusion Fetal thoracic diameter, abdominal diameter and umbilical diameter were found to be significantly associated with gestational age between approximate days 73 to 190 of gestation. Transcutaneous ultrasonography may prove a useful method of estimating gestational age in the absence of accurate breeding records. 相似文献
994.
Napoleón Vargas Jurado Kent M. Eskridge Stephen D. Kachman Ronald M. Lewis 《Journal of Agricultural, Biological & Environmental Statistics》2018,23(2):190-207
In grazing systems, estimating the dietary choices of animals is challenging but can be achieved using plant-wax markers, natural compounds that provide a signature of individual plants. If sufficiently distinct, these signatures can be used to characterize the makeup of a botanical mixture or diet. Bayesian hierarchical models for linear unmixing (BHLU) have been widely used for hyperspectral image analysis and geochemistry, but not diet mixtures. The aim of this study was to assess the efficiency of BHLU to estimate botanical mixtures. Plant-wax marker concentrations from eight forages found in Nebraska were used for simulating combinations of two, three, five and eight species. Also, actual forage mixtures were constructed in laboratory and evaluated. Analyses were performed using BHLU with 2 prior choices for forage proportions (uniform and Gaussian), 2 covariance structures (independent and correlated markers), stable isotope mixing models (SIMM), and nonnegative least squares (NNLS). Accounting for correlations between markers increased efficiency. Estimation error increased when Gaussian priors were used to model forage proportions. Performance of BHLU, SIMM, and NNLS was reduced with the more complex botanical mixtures and the limited number of markers. For simple mixtures, BHLU is a reliable alternative to NNLS for estimation of forage proportions. Supplementary materials accompanying this paper appear online. 相似文献
995.
Merging pedigree databases to describe and compare mating practices and gene flow between pedigree dogs in France,Sweden and the UK
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S. Wang G. Leroy S. Malm T. Lewis E. Strandberg W.F. Fikse 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2017,134(2):152-161
Merging pedigree databases across countries may improve the ability of kennel organizations to monitor genetic variability and health‐related issues of pedigree dogs. We used data provided by the Société Centrale Canine (France), Svenska Kennelklubben (Sweden) and the Kennel Club (UK) to study the feasibility of merging pedigree databases across countries and describe breeding practices and international gene flow within the following four breeds: Bullmastiff (BMA), English setter (ESE), Bernese mountain dog (BMD) and Labrador retriever (LBR). After merging the databases, genealogical parameters and founder contributions were calculated according to the birth period, breed and registration country of the dogs. Throughout the investigated period, mating between close relatives, measured as the proportion of inbred individuals (considering only two generations of pedigree), decreased or remained stable, with the exception of LBR in France. Gene flow between countries became more frequent, and the origins of populations within countries became more diverse over time. In conclusion, the potential to reduce inbreeding within purebred dog populations through exchanging breeding animals across countries was confirmed by an improved effective population size when merging populations from different countries. 相似文献
996.
JC Dockweiler B Cossic CG Donnelly RO Gilbert E Buckles SH Cheong 《Reproduction in domestic animals》2017,52(1):174-178
A three‐year‐old intact female Old English sheepdog was presented for evaluation of infertility. A uterine biopsy was performed during dioestrus, and the microscopic appearance was inconsistent with progesterone stimulation; the glands were sparse, simple and failed to show coiling, while the glandular epithelium was cuboidal instead of columnar. There was very little evidence of glandular activity. Due to the inappropriate appearance of the glands for the stage of the cycle, immunohistochemistry for progesterone receptors was performed. No progesterone receptor‐positive immunoreactivity was identified in the endometrial luminal epithelium, glandular epithelium or stroma. Weak intranuclear immunoreactivity was identified within the smooth muscle cells of the myometrium. The absence of progesterone receptors within the endometrial glands is the most likely explanation for the abnormal appearance of the endometrium and for this bitch's infertility. To our knowledge, this is the first report of endometrial progesterone receptor absence in a bitch. 相似文献
997.
Adjunct fixation with a Kirschner wire or a plate for lateral unicondylar humeral fracture stabilization
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998.
Dutelle AL Bulman-Fleming JC Lewis CA Rosenberg MP 《Journal of Feline Medicine and Surgery》2012,14(10):694-700
This retrospective study evaluated the use of lomustine as a rescue agent for 39 cases of resistant feline lymphoma. Parameters assessed included lymphocyte cell size, number of previous chemotherapy drugs and number of previous chemotherapy protocols received, time from lymphoma diagnosis to initiation of lomustine therapy, body weight and anatomic location of lymphoma. Cell size, number of previous chemotherapy drugs, number of previous chemotherapy protocols and anatomic location were all significant prognostic factors for the progression-free interval. Twenty-one cats (54%) received more than one dose of lomustine. The overall median progression-free interval (MPFI) was 39 days (range 7-708 days). The MPFI for large versus small and intermediate cell lymphomas was 21 versus 169 days, respectively. The MPFI for gastrointestinal versus non-gastrointestinal lymphomas was 180 versus 25.5 days, respectively. Lomustine has an acceptable efficacy and safety for use as a rescue agent in feline lymphoma. 相似文献
999.
1000.
Medical records of cats with high-rise trauma were reviewed to document the prevalence and clinical manifestations of orofacial injury. Cats were presented over a 10-year period from January 2000 to December 2009. Signalment, weight, number of stories fallen, and survival data were recorded in 84 cats and physical examination findings were obtained from 83 cats. Fourteen of these cats were examined by veterinarians of the Dentistry and Oral Surgery Service. Mean age was 37-months. Mean distance fallen was 2.65 stories, and in the majority of cases the substrate the cat fell on was not recorded Overall, survival was 94.0% when including euthanasia as a cause of death and 98.8% when excluding euthanized patients. Orofacial findings included bilateral epistaxis, hard palate fracture +/- tear of palatal soft tissue, palatal soft tissue bruising, mandibular fracture, mandibular symphyseal separation, tongue injury, facial soft tissue injury, dental trauma, and other oral soft tissue injury. Sixty-six percent of cats suffered some degree of orofacial injury. The population was analyzed for the prevalence of each type of injury. An oronasal fistula was seen in one cat as a complication of an untreated hard palate fracture. Possible etiology of the injuries and treatment options are discussed. 相似文献