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1.
Retrospective management and owner-reported injury data, and measurement of forelimb hoof conformation, were collected via a cross-sectional survey from a convenience sample of 96 registered show jumping (n = 67) and dressage (n = 29) horses. Most of the horses were medium- to upper-level performers, aged 9 (interquartile range [IQR] 7–12) years, and in the current rider's ownership for 28 (IQR 12–60) months. The horses were trained 45 (IQR 35–60) minutes, 6 days per week, on a sand or sand mix arena. Failure to train for ≥7 days was reported in 26 of 96 horses, generally associated with lameness diagnosed by a veterinarian (16/29), with a median time-off of 26 (IQR 14–93) days. During the preceding 12 months, 33% of the riders had been working with the farrier on hoof-related issues, 30% of which had involved ≤2 issues. This remedial work often involved a veterinarian (14/30) or allied health practitioner (6/30). Most horses were hot shod (67/89) with conventional fullered shoes. Uneven feet were identified in 16 of 89 horses but were not positively associated with inability to train, possibly reflecting the minor variation between feet. Uneven feet were associated with variation in heel length and angle measurements and a greater sole length and reduced sole width, rather than smaller and boxy. Multiple correspondence plots identified an association of uneven feet with the dressage horses rather than show jumping horses.  相似文献   
2.
本文对引进的30头摩本杂交水牛进行了跟踪检测,对其在近3年多来的生长性能、泌乳性能、适应性、抗病性等的资料统计分析,结果表明:在示范牧场驯化饲养的杂交水牛的成功率100%,其体形外貌、生产性能、体尺体重等方面均比本地水牛有明显的改善,具有很好的开发前景.  相似文献   
3.
Genetic correlations for body measurements and conformation and functional traits in foals and studbook horses with racing traits were estimated in the Finnhorse and Standardbred. Genetic response and accuracy were estimated using records of animal, half‐sibs and parents in selection scenarios for racing traits, for foal and racing traits, for studbook and racing traits, and using records of animal, half‐sibs and parents for foal traits and racing traits of parents. Racing time and earnings were the breeding objective. Low‐to‐moderate genetic correlations for body measurements and racing traits indicated that selection favours bigger horses at all ages. Being mainly favourable for the breeding objective, genetic correlations for conformation and functional traits with racing traits were highest for the foal traits of type, trot and overall grade and for the studbook traits of character and movements. Genetic correlations for foal and studbook conformation with racing traits were low in the Finnhorse and moderate to high in the Standardbred. In foals, the highest genetic correlations were for trot with racing time (?0.54) and with earnings (0.52) in the Finnhorse, and for overall grade with racing time (?0.54) and with earnings (0.54) in the Standardbred. In studbook horses, genetic correlations were high for character with racing time and earnings in the Finnhorse (?0.68, 0.61) and in the Standardbred (?0.63, 0.70), and for movements with racing time and earnings in the Finnhorse (?0.70, 0.69) and in the Standardbred (?0.90, 0.88). To increase accuracy of conformation and functional traits, foal traits would be more useful in the index with racing traits, as being less preselected than studbook traits. The foal traits (type, trot, overall grade) having moderate heritability and genetic correlations with racing traits would be useful in multi‐trait index before a racing career, where the greatest gain is because of a shorter generation interval. It would be feasible to implement for AI stallions.  相似文献   
4.
The long-term effects of gestational immaturity in the premature (defined as < 320 days gestation) and dysmature (normal term but showing some signs of prematurity) foal have not been thoroughly investigated. Studies have reported that a high percentage of gestationally immature foals with related orthopedic issues such as incomplete ossification may fail to fulfill their intended athletic purpose, particularly in Thoroughbred racing. In humans, premature birth is associated with shorter stature at maturity and variations in anatomical ratios, linked to alterations in metabolism and timing of physeal closure in the long bones. We hypothesized that gestational immaturity in horses might similarly be associated with reduced height and different anatomical ratios at maturity. In this preliminary study, the skeletal ratios of horses with a history of gestational immaturity, identified through veterinary and breeder records, were compared with those of unaffected, closely related horses (i.e., sire, dam, sibling). External measurements were taken from conformation photographs of cases (n = 19) and related horses (n = 28), and these were then combined into indices to evaluate and compare metric properties of conformation. A principal component analysis showed that the first two principal components account for 43.8% of the total conformational variation of the horses’ external features, separating horses with a rectangular conformation (body length > height at the withers), from those that are more square (body length = height at the withers). Varimax rotation of PC1 and analysis of different gestational groups showed a significant effect of gestational immaturity (P = .001), with the premature group being more affected than the dysmature group (P = .009, P = .012). Mean values for the four dominant indices showed that these groups have significantly lower distal limb to body length relationships than controls. The observed differences suggest that gestational immaturity may affect anatomical ratios at maturity, which, in combination with orthopedic issues arising from incomplete ossification, may have a further impact on long-term athletic potential.  相似文献   
5.
陈树思 《安徽农业科学》2006,34(15):3613-3615,3624
运用细胞图像分析系统及显微照相的方法,观察研究鳄梨次生木质部导管分子。结果发现,鳄梨次生木质部导管分子中存在着许多不同的样式,并且导管分子穿孔板存在着6种类型:①两端均为一个单穿孔板;②一端为一个单穿孔板,另一端为梯状穿孔板;③两端均为梯状穿孔板;④一端为梯状穿孔板,另一端为奇特样式穿孔板;⑤两梯状穿孔板分别位于同一导管分子相对的侧壁互相对应;⑥一单穿孔板和一梯状穿孔板分别位于同一导管分子相对的侧壁互相对应;还存在一些过渡类型。管间纹孔式为互列纹孔式,导管射线间纹孔式为横列、纵列刻痕状纹孔式。部分导管分子侧壁具有纹饰。分别对其进行了描述,并从导管分子个体发育与系统发育的角度进行了讨论。  相似文献   
6.
To determine associations between carpal and fetlock conformation and later performance, 292 two-year-old (2YO) Thoroughbred horses were examined at a public auction. Two observers graded carpal and fetlock conformation in the frontal view, and subject weights were estimated (weight tape), and height was measured. Subject age, gender, and workout distance and time were retrieved from sales data. Lifetime racing data was retrieved from the Jockey Club database. Mild to moderate deviations from straight forelimb conformation at the carpus or fetlock occurred in 85% of 2YO Thoroughbreds and had no substantive effect on lifetime racing performance. Carpal and fetlock conformation are associated. Greater age, female gender and faster workout were associated with better short and long-term racing outcomes. The ability to start a race at 2YO was associated with improvements in several measures of racing success. The lack of an association of forelimb conformation with most measures of racing performance will assist producers and consumers of young racing stock in the determination of the need for corrective procedures in young horses and the importance of deviations at purchase. Speed of workout and the ability to start at 2YO were associated with each other and with an improvement in several racing outcomes.  相似文献   
7.
奶牛外貌评分与产奶量相关性研究   总被引:1,自引:0,他引:1  
某奶牛场随机取30头奶牛,测定其305d产奶量及10个体型外貌评分性状,计算产奶量与体型性状之间的相关系数,求得产奶量的各自通径系数,研究奶牛10个体型性状与生产效率性状之间的关系。结果表明,整体评分与305d产奶量之间存在弱正相关(P〉0.05);10个评分性状中,后乳房高度和宽度与305d产奶量呈极显著相关(P〈0.01)。乳房中隔和乳房深度与305d产奶量呈显著相关(P〈0.05)。整体外貌评分、后乳房宽度、乳房中隔越高则产奶量也越高,后乳房高度和乳房中隔是对产奶量起主要作用的性状。  相似文献   
8.
黄浩  张鲲 《安徽农业科学》2012,40(11):6622-6625
以成都市锦里古街(Ⅰ期)为例,从锦里古街的项目背景入手,介绍了项目区位环境以及设计构思。从街道类型、空间序列、比例尺度、节点景观4个方面分析了锦里古街的街道空间形态,并通过分析建筑特征、建筑与街道的组合方式来解析锦里古街的建筑形象和空间层次。归纳出锦里古街空间形态设计特征,以期为城市特色步行街的保护和开发提供参考。  相似文献   
9.
The aim of this study was to estimate the genetic parameters of conformation traits in Iranian Thoroughbred race horses. The data set included the conformation records of 607 Thoroughbred horses. In this study, 10 conformation traits were recorded. The effect of sex was significant for length of back line (P < 0.05), withers height (P < 0.05), circumference of front cannon (P < 0.001), and circumference of hind cannon (P < 0.001). The effect of age was significant for all traits (P < 0.01). The genetic parameters were estimated by the restricted maximum likelihood (REML) method using DFREML program. The heritability estimates were for head length 0.39, length of back line 0.41, length of shoulder 0.24, heart girth 0.49, chest width 0.22, withers height 0.38, front cannon height 0.27, circumference of front cannon 0.30, hind cannon height 0.29 and circumference of hind cannon 0.34. The estimates of genetic correlation ranged from 0.18 to 0.96 and those of phenotypic correlation varied from 0.16 to 0.83.  相似文献   
10.
[目的]研究苎麻(Boehmeria nivea L.Guad)韧皮纤维的超微结构。[方法]对苎麻茎韧皮纤维进行光学显微镜和透射电子显微镜观察;并对苎麻单纤维进行组织离解,用光学显微镜进行观察。茎韧皮纤维显微观察结果表明:苎麻韧皮纤维细胞壁横切面分为胞间层、初生壁和次生壁3个层次和细胞腔;次生壁大多为1层,即次生壁外层(S1),并且具有许多同心层次;少数纤维具有2~3层,即次生壁外层、中层(S2)和内层(S3);茎基部纤维次生壁多为2~3层,中部纤维次生壁多为1层,苎麻纤维次生壁层次存在位置差异;苎麻纤维是由若干个纤维细胞相互连接而成,纤维细胞之间部分纤维细胞端壁溶解,部分具细胞膜和初生壁,部分具次生壁。苎麻单纤维光学显微镜结果表明:苎麻单纤维细丝状,纤维细胞壁(次生壁)由Z型微纤丝和S型微纤丝组成,具节和节间,少数纤维具有明显的节状加厚现象;中央略大,两端尖削,或钝圆形、二叉状、火炬状等各种形状。[结论]该研究可为生产高品质的苎麻产品奠定基础。  相似文献   
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