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1.
During March 2001, 117 working mules, randomly chosen from four markets in Morocco, were weighed and a series of body measurements recorded; their age and body condition score were also recorded. Linear regression techniques were used to derive a 'best fit' equation for predicting liveweight from the other variables. For the working mules weighing between 131 and 391 kg the best prediction equation using two variables was: liveweight (kg) = -33 + 2.8 x heart girth (cm)+1.36 x length (cm). Other prediction equations available for estimating the liveweight of equidae were tested on the data, but in all cases they significantly overestimated the weights of the Moroccan mules.  相似文献   

2.
This review discusses the literature on B. burgdorferi infections in view of the rising incidence of this infection in general and the increasing concerns of horse owners and equine practitioners. Lyme disease, the clinical expression of Borrelia infections in man is an important health problem. The geographic distribution of B. burgdorferi infections in equidae should resemble that of human cases because the vector tick involved, Ixodes ricinus, feeds on both species and, indeed, the infection has been established many times in horses. However, a definite diagnosis of the disease "Lyme borreliosis" in human beings as well as in horses and other animals is often difficult to accomplish. Although a broad spectrum of clinical signs has been attributed to B. burgdorferi infections in horses, indisputable cases of equine Lyme borreliosis are extremely rare so far, if they exist at all.  相似文献   

3.
OBJECTIVE: To determine outcome associated with cutaneous tumors treated via intratumoral chemotherapy with cisplatin and identify risk factors affecting local tumor control and complications in equidae. DESIGN: Retrospective case series. ANIMALS: 573 equidae with 630 cutaneous tumors. PROCEDURES: Medical records of horses, mules, donkeys, and ponies with cutaneous tumors treated via intratumoral chemotherapy with cisplatin were analyzed. RESULTS: 549 horses, 13 mules, 8 donkeys, and 3 ponies with 630 histologically confirmed cutaneous tumors were included. Tumors included sarcoids (n = 409), squamous cell carcinomas (151), soft tissue sarcomas (28), cutaneous lymphomas (26), and melanomas (16). Overall cure rate, defined as local control at 4 years, was 93.3%. For all tumor stages combined, cure rates after 1 course of treatment were 96.3% for sarcoids, 96% for lymphomas, 88% for squamous cell carcinomas, 85% for soft tissue sarcomas, and 81% for melanomas. Treatment protocol, tumor stage, and prior treatment were significant prognostic factors for tumor control. Treatment efficacy was lower for large tumors, those with gross postoperative residual disease, and those that had been treated previously with other modalities. Treatment was well tolerated. Local reactions were more likely to occur and to be more severe after the third and fourth treatment sessions. CONCLUSIONS AND CLINICAL RELEVANCE: Results confirmed the value of intratumoral chemotherapy with cisplatin for treatment of cutaneous tumors in equidae.The results cannot be extrapolated to other formulations of cisplatin or other protocols that might be used.  相似文献   

4.
Summary This review discusses the literature on B. burgdorferi infections in view of the rising incidence of this infection in general and the increasing concerns of horse owners and equine practitioners. Lyme disease, the clinical expression of Borrelia infections in man is an important health problem. The geographic distribution of B. burgdorferi infections in equidae should resemble that of human cases because the vector tick involved, Ixodes ricinus, feeds on both species and, indeed, the infection has been established many times in horses. However, a definite diagnosis of the disease "Lyme borreliosis" in human beings as well as in horses and other animals is often difficult to accomplish. Although a broad spectrum of clinical signs has been attributed to B. burgdorferi infections in horses, indisputable cases of equine Lyme borreliosis are extremely rare so far, if they exist at all.  相似文献   

5.
Phylogenetic research on the teeth of equidae beginning with dagger Hyracotherium ('Eohippus') will be summarized, subdivided into its components, analysed in a new way and finally interpreted according to several theories of evolution. In this context, specific cells (ameloblasts, odontoblasts, cementoblasts) are discussed and valued according to Preuss (1987) as active carriers of the evolution of teeth.  相似文献   

6.
提高牛人工授精受胎率技术   总被引:9,自引:2,他引:9  
文章从母牛繁殖机能、冻精质量、冻精解冻的温度、时间及方法、母牛发情鉴定、黄牛和水牛繁殖的差异、输精方法、输精时间、榆精部位、技术培训和养牛综合配套技术等方面阐述了提高黄牛、水牛冻精配种受胎率的技术措施。  相似文献   

7.
卵巢组织玻璃化冷冻可替代直接冷冻卵母细胞或胚胎。玻璃化冷冻卵巢组织在辅助生殖上具有优越性。它无需控制供体的生殖周期 ,也无需取出卵泡。同样这一技术可用于保存濒危动物或受意外伤害的人或动物的卵母细胞 ;可为性成熟前失去生殖能力的动物或人提供生殖保险以及增加卵母细胞的来源 ;可用于建立生殖细胞 (卵母细胞 )的冷冻库。而传统的冷冻技术存在很多弊端。文章综述了玻璃化冷冻卵巢组织的研究背景和现状 ,并指出了其广阔的应用前景  相似文献   

8.
动物胃肠道微生物具有很强的代谢活性,对宿主的营养物质利用和生理代谢功能具有重要调控作用,可影响动物的生产性能和机体健康。为了适应胎儿的生长发育,妊娠期间母体的肠道菌群组成和代谢活性发生显著变化。笔者结合自己近年来的研究成果,对国内外母猪肠道微生态与繁殖生理方面取得的研究进展进行综述,以期为研发提高母猪繁殖性能的调控技术提供思路。  相似文献   

9.
Reproductive technologies aim at improving fertility with the ultimate result of improving genetic selection. In equidae, the respective contribution of different methods of horse management and breeding to genetic progress remain difficult to evaluate as breeding strategies affect the number of offspring per mare or stallion whereas different selection methods (based on pedigree, performance, genomics or progeny’s performance) will be applicable at different ages, leading to different accuracy in the estimation of the breeding value. Here, a mathematical model was applied to evaluate theoretical genetic progress depending on breeding conditions in horses. The model showed that for breeding systems ranging from 0.6 to 2 foals/year/mare and from 10 to 150 foals/year for stallions, when selection of the best animals is strictly made by a truncation, the genetic progress is accelerated by (1) increasing the number of offspring per year, (2) the start of reproduction as soon as the age of 2 in both sexes, and (3) reducing the number of years of use for stallions from 10 to 5 years. The calculation showed that using all ways of improvement could provide an increase in genetic progress of up to +270% and +226% in mares and stallions, respectively, above the basal reference situation of 100%. In the Selle Français breed, the observed reproductive management parameters (10 years generation interval, 10 foals/stallion and 0.55 foals/mare) are close to the worst conditions of the model. In addition, the best mares are not selected for breeding. In conclusion, new reproductive technologies, genomic selection, and breeding younger animals will increase genetic gain.  相似文献   

10.
Extract

Recent advances in reproductive physiology offer ways for exploiting superior, female cattle and for manipulating physiological events such as parturition. The techniques involved in these advances and their associated hazards are the subject of this review.  相似文献   

11.
REASONS FOR PERFORMING STUDY: The minute anatomy of the temporomandibular joint (TMJ) in horses is poorly documented in the literature. OBJECTIVES: To examine in detail the anatomy of the normal equine TMJ and the relationship of the joint to adjacent structures. METHODS: The anatomy of the TMJ was examined in 12 equidae using dissections, synovial and vascular injections and frozen and plastinated sections. Relevant structures were photographed. RESULTS: Rostral and caudal compartments were identified in the dorsal and ventral synovial pouches of the TMJ. Lateral and caudal ligaments were identified and attachments of the masticatory muscles over the TMJ were documented. Direct relationships between the TMJ and components of the ear were found, and the vascular supply described. CONCLUSIONS: This joint is related to some components of the ear as in man, and has its own peripheral vascular supply. Potential relevance: A knowledge of the detailed anatomy of the equine TMJ is a prerequisite to interpreting the imaging techniques, and will enable improved diagnosis of TMJ pathologies.  相似文献   

12.
The objective of this review is to evaluate the effectiveness of using pharmacological compounds on reproductive outcomes, particularly litter size, in North American swine. While the opportunity to improve reproduction in North American pigs exists, numerous hurdles need to be overcome in order to achieve measureable results. In the swine industry, the majority of piglet losses are incurred during pregnancy and around farrowing. Over the last 20 years, a reduction in losses has been achieved through genetic selection and nutritional management; however, these topics are the focus of other reviews. This review will evaluate attempts to improve litter size by reducing losses at various stages of the reproductive process, from the time of conception to the time of farrowing, using pharmacological compounds. Generally, these compounds are used to either alter physiological processes related to fertilization, embryonic attachment or uterine capacity, etc., or to facilitate management aspects of the breeding females such as inducing parturition. Although some of the pharmacological agents reviewed here show some positive effects on improving reproductive parameters, the inconsistent results and associated risks usually outweigh the benefits gained. Thus, at the present time, the use of pharmacological agents to enhance reproduction in North American swine may only be recommended for herds with low fertility and presents an avenue of research that could be further explored.  相似文献   

13.
Many fillies and mares are accused of behaving badly by their owners or trainers, and their reproductive hormones and ovaries are commonly blamed for this. Overt oestrus behaviour, however natural, is undesirable when a horse is being ridden, trained and competed. More subtle behaviours may be attributed to the reproductive cycle and presented as the cause of poor performance in the elite competition mare. Sometimes behaviours are complex, perhaps at odds with what one expects for normal reproductive behaviour and in many cases may not be associated with the reproductive cycle at all, rather associated with pain of musculoskeletal or soft tissue origin. The situation represents a diagnostic dilemma to positively associate undesirable behaviours with the ovarian hormones or ovarian pain, before an attempt can be made to modify the behaviour through the suppression of oestrus. This article will review the reasons for presentation, the behavioural patterns of the reproductive cycle and the diagnosis of reproductive behavioural problems. The range of techniques for oestrus suppression will be reviewed along with their clinical application and any known current regulatory issues associated with their use.  相似文献   

14.
作者对2017年国内外家兔遗传育种(传统育种、分子育种、繁殖技术)相关的研究进展进行了综述,发现国内外研究侧重不同,且与往年相比存在明显变化。国内传统育种主要包括品种选育和性状评定两方面研究,并取得了良好的进展;在分子育种领域做了较多的研究,主要涉及性状包括生长、肉质、皮毛、繁殖、抗病性能等,并筛选了与目标性状相关联的功能性基因和分子标记;繁殖技术研究少而散,包括人工授精、配种季节和光控管理等环境效应对家兔健康和生产力影响的研究。国外传统育种包括性状遗传评估、遗传与环境互作、评估方法等,在改进生长性能和肉质方面得到了提升;分子育种主要涉及生长、肉质、抗病及繁殖等性状,也进行了分子标记筛选与研究,但在皮毛性状方面研究相对欠缺;繁殖技术主要包括环境和添加物对家兔繁殖、精液冷冻等方面的影响研究,也取得了良好进展。本综述可为后期家兔育种研究和生产提供参考。  相似文献   

15.
Laparoscopic hernioplasty techniques have been developed in the recent years to avoid the recurrence of inguinal hernias and to spare the testicles for breeding purposes in stallions. However, there have been no previous comprehensive and systematic studies of the reproductive outcomes and prognoses for stallions after inguinal hernioplasty. Therefore, the objective of this study was to assess the possible effects of one of these techniques (standing laparoscopic peritoneal flap hernioplasty) on the sperm production and motility characteristics of six healthy stallions that received this procedure based on 1‐year follow‐ups. There were no significant differences in the measured sperm variables (assessments based on the DSO, MOT, PMOT, VSL, VCL and VAP) during 1‐year follow‐ups.  相似文献   

16.
生殖发育关系到一个物种的繁衍生息。哺乳动物的雌性生殖细胞,也就是卵母细胞,其生殖能力的获得需要同时经历两个过程:卵子发生和卵泡发育,而这两个相互依存的过程将为雌雄配子相互结合及新一代个体发育的起始奠定基础。随着分子生物学技术的发展,许多与卵泡发育相关的基因表达调控机制逐渐被揭示出来,新观点纷纷涌现。作者将对哺乳动物卵泡生长发育各阶段的主要分子通路研究进展进行综述,旨在为卵子干细胞的研究、治疗性克隆的发展、卵子减少不孕症等人类疾病的治疗和研究提供理论依据;此外,本综述还将对畜牧业中加快卵泡的发育进程、充分利用早期卵母细胞资源、缩短世代间隔、提高繁殖率等产生重要的指导意义。  相似文献   

17.
Reproductive development is related to the survival and thrives of one species.The female mammalian germ cell, that is oocyte, will obtain their reproductive capacity through two processes:Oogenesis and follicle development.These two interdependent processes will provide the foundations for the combination of male and female gametes, and for the starting of a new generation of ontogeny.With the development of molecular biology techniques, many regulatory mechanisms of gene expressions, which associated with follicle development, is revealed gradually.New ideas have emerged.This present review will summarize the major molecular pathways, which occurred at different mammalian follicle development stages.And these summarizations will provide theoretical basis for the studies of germ stem cells, development of therapeutic cloning, and the treatment and research of human reproductive diseases.In addition, the paper will also show the guiding significance to the acceleration of development of animal husbandry, utilization of early oocytes resources, shortening of the generation interval and improvement of reproductive rate.  相似文献   

18.
Equine reproductive technologies, such as cloning and intracytoplasmic sperm injection (ICSI) have become routine laboratory practice in many parts of the world. In this review, we will discuss novel cloning approaches that have just recently become commercial, update the latest cloning results at Crestview Genetics in Argentina and at In Vitro Clonagem in Brazil, and discuss differences in techniques and approach within the American equine ICSI market from four different laboratories commercially producing equine ICSI.  相似文献   

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