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A model was developed to explain the influence of different local and regional factors on the prevalence of foot-pad dermatitis in broilers at the time of slaughter. Data from a recent two-year study of broiler foot-health in Sweden were used to construct the model. The model was based on regression analysis, using a Tobit model for censored data. This type of Tobit regression model has been used for several decades in econometrics and can also be found in the medical-scientific literature. It has, however, reportedly not been used in veterinary medicine although there appears to be several situations where it should be considered useful. Week of slaughter was significantly (p<0.001) associated with total foot-pad score, which decreased over time. The birds' age at slaughter was also significantly (p<0.01) associated with total foot-pad score. Five out of the 11 slaughterhouses included in the study were included as significant (p<0.01) variables in the final model. Three feed suppliers (p<0.05) and four regions (p<0.01) were also included as significant variables in the model. There were also significant (p<0.001) interactions between several of these factors (mainly, between the time variable and specific slaughterhouses, feed suppliers or regions, respectively).

The information gathered in this study regarding the influence of a number of risk factors for the development of foot-pad dermatitis and their reciprocal interactions will enable us to modify the Swedish broiler foot-health programme.  相似文献   

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基于AIP公司的生产实践,对中小型制造企业生产异常情况的成因、分类及影响进行了归纳、分析和探究。针对由中小型制造企业生产中的诸多因素所导致的生产异常情况不能及时反馈和处理这一难题,以及生产效率和交货期等难以管控的现状,设计了一套对生产过程异常情况进行控制的可行性方案,构建了一种用于车间生产异常事件信息实时采集、快速分析、趋势预判和综合查询信息管理系统。该异常管理系统已被AIP公司成功应用,实践证明它可以全面提高中小型制造企业对生产异常情况处理的及时性、有效性,使生产异常问题的处理实现了规范化、标准化和信息化。这不仅为AIP公司创造了良好的经济效益,而且也为其他中小型制造企业解决此类问题提供了有益参考。  相似文献   
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以华南某1 500头规模种猪场2009年到2010年1 502窝长白猪分娩信息进行优化、选配减少近交畸形的研究,结果显示血缘选配优化时将近交系数控制在1%比3%效果明显,平均产活仔数从10.39头/窝提高到10.46头/窝(P>0.05),畸形率从10.30%下降到4.79%(P<0.01);对其中402窝出现畸形仔猪...  相似文献   
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OBJECTIVES: To evaluate the tear film qualitatively and conjunctival goblet cell numbers in cats with and without corneal sequestra. ANIMALS STUDIED AND PROCEDURES: This was a prospective evaluation of 11 cats with corneal sequestra and 14 control eyes that were either the contralateral normal eye when the sequestrum was unilateral or from control cats of similar age with no ocular disease. All cats in this study were examined by a veterinary ophthalmologist. The ophthalmic examinations included a neuro-ophthalmic evaluation, Schirmer tear tests, fluorescein staining, tear film break-up times, applanation tonometry, biomicroscopy, and indirect ophthalmoscopy. The palpebral conjunctiva at the dorsal nasal, ventral nasal, dorsal temporal and ventral temporal fornices were biopsied after topical anesthetic was applied to the cornea and conjunctiva. The conjunctival biopsies were fixed in formalin and sectioned routinely and stained with hematoxylin and eosin, and periodic acid-Schiff. These slides were examined by light microscopy by a blinded examiner. Goblet cell numbers were compared to conjunctival basal epithelial cell numbers by region. The goblet cell numbers by region from the eyes with sequestra was statistically compared to those from eyes without sequestra, with a student's paired t-test. Conjunctival swabs were collected from the cats with corneal sequestra and submitted for polymerase chain reaction for Herpes felis, Chlamydia psiitticia, and Mycoplasma felis. The corneal sequestra were removed by surgical keratectomy and fixed and stained routinely, and examined by light microscopy. RESULTS: No neurologic abnormalities were detected in any of the cats. The Schirmer tear tests (eyes with sequestra 14+/-5.1 mm/min; normal eyes 15+/-6.8 mm/min) and intraocular pressures (eyes with sequestra 21+/-6.6; normal eyes 22+/-5.8) were within normal reference ranges for cats. Biomicroscopic examinations revealed varied sizes and depths of brown- and amber-colored corneal sequestra. No abnormalities were noted on indirect ophthalmoscopic examinations. The tear film break-up time was 21 s (+/-12) for the normal eyes (n=14) and 14 s (+/-13) in eyes with corneal sequestra (n=11). The average goblet/epithelial cell ratios by region for the normal eyes and the eyes with sequestra respectively were 0.66, 0.56 for the dorsal nasal fornix, 0.68, 0.57 for the ventral nasal fornix, 0.63, 0.48 for the temporal dorsal fornix, and 0.55, 0.49 for the temporal ventral fornix. There were no significant differences in tear film break-up times and goblet cell numbers in eyes with corneal sequestra and those without sequestra. Three conjunctival swabs from two of 11 cats with sequestra were positive with PCR for Herpes felis virus. These included one cat with bilateral sequestra and one cat with unilateral corneal sequestrum. CONCLUSIONS: The pathogenesis of feline corneal sequestra does not appear to be linked primarily to abnormal goblet cell numbers, qualitative tear film abnormalities, and accelerated tear film break-up time.  相似文献   
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A four-year-old female-like Quarter Horse was admitted for clinical evaluation because of masculinized-aggressive behavior and lack of estrous signs. On external inspection, a hypertrophied clitoris and prominent muscles were observed. On gynecological examination, apparently normal mammary glands, vulva, vagina, and cervix were noted. On the other hand, the uterus had no tone and was smaller than normal. The left gonad was very soft on palpation and the right gonad was mostly firm, irregular, and wider than the left gonad. On ultrasound examination, there were no signs of regular ovarian structure or follicular activity. Because of the different shapes and consistencies of the gonads and a suspicion of increased testosterone production, a bilateral gonadectomy was recommended. Blood was collected for testosterone levels quantification and for cytogenetic and molecular investigations. After removal, gonads were analyzed macroscopically and sections were sent for histopathological examination. A final diagnosis of benign adult teratoma associated with seminiferous tubules and Leydig cells was made. On cytogenetic and molecular analyses, a normal diploid number of 64 chromosomes and the presence of the XY sex chromosomes were seen in all cells, as well as the SRY gene. Testosterone levels were higher than normal before surgery and were reduced after gonads removal. In conclusion, the masculinized behavior was probably caused by increased testosterone levels produced by testicular tissue, in a female-like horse with 64,XY SRY-positive disorder of sex development, which was associated with a teratoma.  相似文献   
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笔者拟探讨疏肝益阳胶囊(SGYY)对炔雌醚(QES)诱导大鼠生精紊乱和氧化应激的缓解作用及机制。将20只8周龄雄性SD大鼠随机分为4组,适应饲养1周后,进行药物灌胃处理,对照组:0.1mL生理盐水+0.1mL橄榄油;SGYY组:100 mg·kg-1 SGYY;QES组:0.1 mg·kg-1 QES;QES+SGYY组:0.1 mg·kg-1 QES+100mg·kg-1 SGYY。QES溶于橄榄油;SGYY溶于生理盐水;每天1次,连续2周。处理结束后,取睾丸、附睾、精囊腺和前列腺称重、测量长径与短径,并制备睾丸组织切片,通过HE染色,观察睾丸生精小管组织结构、生精细胞比例的变化;通过免疫组织化学方法检测睾丸生精细胞PCNA表达,Tunel法检测细胞凋亡;分离血浆,检测睾酮含量变化。取睾丸匀浆检测抗氧化酶活性。结果显示,QES处理后大鼠生殖器官的质量显著下降,附睾的精子数量显著减少;生精小管的面积、直径、生精上皮的高度和生精细胞数量均显著减少。而且,生精细胞的PCNA表达和血浆睾酮含量明显下降,Tunel阳性细胞数明显增加。睾丸SOD、GSH-Px和T-AOC活性显著下降,MDA含量显著升高。SGYY增加生殖器官质量、精子数量、睾丸睾酮含量、增殖的生精细胞数量和抗氧化酶活性,降低了MDA含量和Tunel的表达。结果表明,SGYY通过改善抗氧化功能、抑制氧化应激及促进睾酮分泌等途径增加了生精细胞数量并提高睾丸的生精功能。  相似文献   
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Seriolella violacea, a new species to be potentially farmed in Chile and Peru, has shown cranial malformations during farming that could adversely affect its commercial development. This study seeks to generate early knowledge of the osteological development and type of cranial abnormalities that this species presents under culture conditions. Larvae from wild caught broodstock were reared from 1 to 60 days post hatching (DPH) (4.8 ± 0.1 mm TL and 11.8 ± 1.0 mm TL respectively). Larvae samples were collected throughout the experimental trial for recording cranial osteological development and abnormalities in cartilage and bone. At 5.7 ± 0.1 mm TL, coraco‐scapular, sclerotic, ethmoid plate and quadrate cartilages were present. At 8.0 ± 0.6 mm TL, early ossification was observed in the jaw, premaxilla and maxilla. At 11.8 ± 1.0 mm TL, the branchiostegal rays, jaw, maxilla and opercular complex were ossified. The first cartilaginous structures observed were the Meckel's cartilage, the branchial arches and the suspensory ligament. The first cranial malformations were detected at 5.7 ± 0.1 mm TL, coinciding with mouth opening. The most frequent malformations were a curvature of the lower jaw (23.1%), abnormal separation between branchial arches and the Meckel's cartilage (19.4%) and bulging jaws (15.7%).  相似文献   
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