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991.
Tracheal collapse is an uncommon clinical disorder in horses but when present can be difficult to correct. Various medical and surgical procedures to correct tracheal collapse have been described in horses with variable success. Recently, the use of an intraluminal stent has been described as a treatment for tracheal collapse in a miniature horse. The long‐term management, utilising intraluminal stents, in 2 miniature horses with tracheal collapse is presented here. In particular, various complications as a result of intraluminal stent placement are described, the most persistent being the formation of granulation tissue at various regions of the stents. Multiple methods of combating granulation tissue in this situation also are discussed.  相似文献   
992.

This study aimed to determine the trends in milk production, fertility, temperature-humidity index (THI), and herd size in dairy herds from the Laguna region in northern Mexico. Records of 16 dairy herds of Holstein cows from January 2002 to December 2016 were used. Milk production was categorized in low and high levels. Milk production and fertility were analyzed using generalized equation estimation procedures by a model of repeated measures that included the effect of year, month, and productive level, an interaction for month × productive level, and herd effect was nested in productive level. For THI, a generalized linear model that included the effects of year and month was used. Dairy herds with high levels of milk production yielded more milk than those with low levels (P?<?0.001). Milk production in 2002 and 2016 was 27.4?±?0.6 and 32.3?±?0.7 L/cow/day, respectively. Fertility fluctuated throughout the study. Dairy herds with high levels of milk production recorded higher fertility than those with low levels (P?<?0.001). From October to April, THI was <?70, whereas it was >?73 from May to September, indicating that cows were in heat stress (20 h/day). The median herd size was 995 and 2569 cows in 2002 and 2016, respectively. In conclusion, in large herds, milk production increased over the years of study, whereas fertility showed a wave cycle; nonetheless, when THI was >?73, both milk production and fertility decreased.

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993.

The objective of the present study was to evaluate the accuracy of six different equations for weight estimation of camels using body measurements as chest girth, height at withers, and hump girth in order to identify the most reliable equation for use in the field. The prediction equations that were compared were those of Boué Revue d’Élevage et de Médecine vétérinaire des Pays tropicaux 3 (1), 13–16, 1949; Graber Revue d’Élevage et de Médecine vétérinaire des Pays tropicaux, 19, 527–543, 1966; Wilson Tropical Animal Health and Production, 10, 19–25, 1978; Field Proceedings of the Khartoum workshop on camels V1, 209–230, 1979; Bucci et al. Indian Veterinary Journal, 61, 26–30, 1984; and Yagil A Handbook for Camel Breeding, 1994 noticed as BW1, BW2, BW3, BW4, BW5, and BW6, respectively. The dataset used for this evaluation is the one published by Boué Revue d’Élevage et de Médecine vétérinaire des Pays tropicaux 3 (1), 13–16, 1949. Range observed in predicted weight, mean prediction error (MPE), residual mean square (MSE), mean square prediction error (MSPE), coefficient of determination (CD), and concordance correlation coefficient (CCC) were used to assess the different body weight prediction equations. Moreover, paired t tests were applied to compare the true weight and each of the six predicted weights. From the six prediction equations, range observed in predicted weights varied from 193 to 237 kg, MSE from 335.5 to 806.1, MPE from ??129.8 to 24.7 kg, MSPE from 329.4 to 17,617.1, CD from 0.753 to 0.867, and CCC from 0.162 to 0.928. BW4 presented the best prediction results, showing a low MSE, high CD and CCC, whereas BW3 yielded the least accurate estimate of body weight and had weak statistics. The study concluded that BW4 is the most reliable of all equations to estimate camel’s body weight, whereas BW3 is less reliable and its use must be discontinued.

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994.
Dogs have undergone an intensive artificial selection process ever since the beginning of their relationship with humans. As a consequence, a wide variety of well‐defined breeds exist today. Due to the enormous variation in dog phenotypes and the unlikely chance of gene exchange between them, the question arises as to whether they should still be regarded as a single species or, perhaps, they be considered as different taxa that possess different reproductive traits. The aim of this study was therefore to characterize some male reproductive traits, focusing on kinematic characteristics of dog spermatozoa from several breeds. Thirty‐seven dogs from the following breeds were used: Staffordshire Bull Terrier, Labrador Retriever, Spanish Mastiff, Valencian Rat Hunting Dog, British Bulldog and Chihuahua. Semen samples were obtained via manual stimulation and diluted to a final sperm concentration of 50 million/ml, and they were subsequently analysed by the computer assisted semen analysis (CASA‐Mot) ISAS®v1 system. Eight kinematic parameters were evaluated automatically. All parameters showed significant different values among breeds and among individuals within each breed. The fastest sperm cells were those of Staffordshire Bull Terriers and the slowest were recorded in Chihuahuas. The intra‐male coefficient of variation (CV) was higher than the inter‐male CV for all breeds with the Staffordshire Bull Terrier showing the lowest values. When taking into consideration the cells by animal and breed, discriminant analyses showed a high capability to predict the breed. Cluster analyses showed a hierarchical classification very close to that obtained after phylogenetic studies with genome markers. In conclusion, future workers on dog spermatozoa should bear in mind major differences between breeds and realize that results cannot be extrapolated from one to another. Because sperm characteristics are associated with breed diversity, dogs may represent a good model to examine changes in reproductive parameters associated with selection processes.  相似文献   
995.
Actinobacillosis usually is a sporadic infection that affects the tongue in cattle (“wooden tongue”) with possible spread to the digestive tract. Two 4‐year‐old Rouge‐des‐Prés cows from a single French beef herd were referred for chronic (2‐6 months) swelling and cutaneous nodules in the distal hind limbs. In addition to cutaneous signs, physical examination disclosed cachexia, lameness, lymphadenitis of the hind limbs, and pneumonia in both cows. Cytologic examination of direct skin smears was inconclusive, and no parasites were observed in examination of multiple skin scrapings. Histopathological examination of skin and lung biopsy specimens identified chronic, diffuse, severe pyogranulomatous dermatitis, associated with Splendore‐Hoeppli phenomenon and intralesional Gram‐negative bacteria. Cultures from skin, lymph nodes, and lungs (both cows were euthanized for welfare reasons) identified a Pasteurellaceae organism, confirmed as Actinobacillus lignieresii by partial sequencing of the rpoB gene. This report emphasizes that actinobacillosis can appear as a small outbreak in cattle with cutaneous and respiratory signs.  相似文献   
996.
In the pork industry, artificial insemination and the storage of boar semen in liquid at 17°C are routinely applied to optimize the ejaculate and bring about rapid genetic changes that are reflected in the animal protein. Although the results are satisfactory, they are below what occurs with natural mating. It is currently possible to preserve boar semen with storage at 17°C and slow freezing, since to date there is only one study on vitrification, with negative results applicable only in the case of implementing an intracytoplasmic sperm injection. In both methods and due to the sensitivity of boar sperm to osmotic and temperature changes, there is a loss in the quality of the initial sample; however, slow freezing in boar semen has greater deleterious effects on the sample that are reflected in the pregnancy rates and number of live births. Therefore, only 1% of all inseminations are done with frozen semen. The aim of this review is to provide advances and results of studies conducted on the preservation of boar semen, delving more deeply into the critical points that each of the preservation techniques presents, including bacterial contamination, extender components, temperature, ice nucleation, use of additives in extenders and the main deleterious effects on sperm quality.  相似文献   
997.
This research aims to make an analysis of significant parameters in wine grape from Czech Republic. It was evaluated pH, content of sugar, ascorbic acid, titratable acidity, total phenolic content and texture properties. For analyzes 5 samples of wine grape were used, harvested during the three periods. The results show that during the ripening of wine grapes there were changes of selected qualitative parameters, particularly of total polyphenols, sugar and some varieties of wine grape also ascorbic acid (significantly in the variety ’Grüner Veltliner’, ’Chardonnay’, ’Pinot Blanc’). Pronounced changes qualitative parameters were among wine grapes harvested the 1st and 2nd seasons. Changes in textural properties also occurred during the harvest and for most varieties between 2nd and 3rd period of harvest. The PCA grouped chemical parameters of wine grape in independent sets and can be used as assessment tool of wine cultivars.  相似文献   
998.
中草药饲料添加剂是一种兼具营养价值和药用价值的新型绿色饲料添加剂,可以促进动物机体生长发育,提高动物生产性能,增强动物机体抗病能力,同时还具有毒副作用小、无残留、无耐药性等优点。阐述了中草药饲料添加剂的特点及其在反刍动物生产中的应用,以期为中草药饲料添加剂的科学、合理利用提供参考。  相似文献   
999.
1000.
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