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1.
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   

2.
OBJECTIVES: To evaluate whether dogs with megaoesophagus due to myasthenia gravis display less oesophageal dilatation radiographically than dogs with other causes of megaoesophagus. METHODS: Thoracic radiographs of 66 dogs with megaoesophagus in which concurrent acetylcholine receptor antibody titre was known were analysed retrospectively. Maximum oesophageal diameter was transformed to a "relative oesophageal diameter" using a ratio with thoracic inlet diameter. Dogs were divided into two groups according to "MG" or "non-MG" antibody status and median relative oesophageal diameter values were compared between groups and with age, weight and sex. A receiver operating characteristic plot was used to evaluate a suitable relative oesophageal diameter cut-off. RESULTS: Twenty dogs were diagnosed with myasthenia gravis and 46 with other causes of megaoesophagus. Thoracic inlet size correlated significantly with bodyweight and surface area (r(2)=0.627 and 0.669, respectively). Median values of relative oesophageal diameter for the MG group and non-MG group were 0.58 and 0.66, respectively, and these showed a small, but significant, difference (P=0.029), although there was complete overlap in the range of relative oesophageal diameter values between groups. There was no significant association between relative oesophageal diameter and sex, age or weight or significant difference in age, sex or weight between the two groups. An increased odds ratio for myasthenia gravis existed in golden retrievers and German shepherd dogs. CLINICAL SIGNIFICANCE: Relative oesophageal diameter appears to be of limited diagnostic utility in distinguishing dogs with megaoesophagus due to myasthenia gravis from those with megaoesophagus due to other causes.  相似文献   

3.
In humans, pancreatic hyperechogenicity and duct dilation are reported as normal aging changes. Similar changes have been reported with pancreatitis in the cat. We attempted to determine if aging changes occur in the ultrasound appearance of the normal feline pancreas. The pancreas of 84 normal (based on history, physical exam, biochemical profile, and feline trypsin-like immunoreactivity and pancreatic lipase immunoreactivity concentrations) cats of varying ages was scanned. Pancreatic width at the left limb and body, pancreatic duct diameter at left limb and body, and pancreatic echogenicity compared with liver and surrounding fat were noted and compared with age and body weight. Lower and upper limits of the 95% reference intervals for pancreatic left limb width were 2.6 and 9.5 mm, and 3.5 and 8.5 mm for the pancreatic body width. There was no significant difference in pancreatic width between the left limb and body. Lower and upper limits of the 95% reference interval for the diameter of the pancreatic duct at the left limb and body were similar, and were 0.65 and 2.5 mm. There was a weak but significant linear correlation between pancreatic duct diameter and age, with increasing pancreatic duct diameter with increasing age. There was no correlation of pancreatic width with age, and no correlation of pancreatic echogenicity with age or body weight. Based on this study, feline pancreatic size and echogenicity do not change with age. Pancreatic duct diameter increases slightly with age and should not be used as a sole indicator of pancreatitis in the geriatric cat.  相似文献   

4.
本试验旨在研究筛片孔径、调质温度、模孔直径的不同工艺参数组合对肉鸡颗粒饲料加工质量、生长性能和养分表观消化率的影响。以玉米-豆粕型全价配合饲料为肉鸡试验饲粮,在相同配方及模孔长径比一致的条件下,设计3因素2水平(筛片孔径:2.0和2.5 mm;调质温度:70和80℃;模孔直径:3和4 mm)的肉鸡颗粒饲料加工试验,选用864只1日龄爱拔益加(AA)肉仔鸡,随机分为8个处理,每个处理6个重复,每个重复18只鸡。饲养试验共42 d,分1~21日龄和22~42日龄2个阶段。结果表明:1)筛片孔径和模孔直径的交互作用以及调质温度和模孔直径的交互作用对颗粒硬度有极显著影响(P0.01),调质温度和模孔直径的交互作用、筛片孔径和调质温度的交互作用以及筛片孔径、调质温度和模孔直径的交互作用对颗粒耐久性有极显著影响(P0.01),筛片孔径和模孔直径的交互作用对颗粒耐久性有显著影响(P0.05)。2)调质温度对1~21日龄肉鸡末重、平均日增重和平均日采食量有极显著影响(P0.01),对22~42日龄肉鸡末重有极显著影响(P0.01)。3)肉鸡1~21日龄,筛片孔径、调质温度以及2因素的交互作用对肉鸡养分表观消化率的影响不显著(P0.05);肉鸡22~42日龄,筛片孔径、调质温度和模孔直径的交互作用对肉鸡干物质、能量和粗蛋白质表观消化率有极显著影响(P0.01)。综合得出:相同筛片孔径和模孔直径下,颗粒硬度和耐久性随调质温度升高有增大趋势;相同筛片孔径和调质温度下,颗粒硬度和耐久性随模孔直径的增大有降低趋势;肉鸡1~21日龄,筛片孔径选择2.0和2.5 mm均可,调质温度为70℃时肉鸡的生长性能极显著高于80℃时,且料重比显著低于80℃时;肉鸡22~42日龄,当筛片孔径为2.0或2.5 mm、调质温度为70℃、模孔直径为4.0 mm时肉鸡生长性能较高、料重比较低;肉鸡1~42日龄,当筛片孔径为2.0或2.5 mm、调质温度为70℃、模孔直径为4.0 mm时肉鸡的生长性能较高、料重比较低;当筛片孔径为2.5 mm、调质温度为80℃时,1~21日龄肉鸡干物质、能量和粗蛋白质表观消化率较高;当筛片孔径为2.5 mm、调质温度为70℃、模孔直径为4.0 mm时,22~42日龄肉鸡干物质、能量和粗蛋白质表观消化率最高。  相似文献   

5.
Sixteen pregnant red deer hinds were scanned using real-time ultra sound at regular intervals during the first 150 days of pregnancy. In the early stages of pregnancy, an intra-rectal linear array transducer was used but later in pregnancy the hinds were scanned externally with a sector scanner. Pregnancy was determined from 30 days of gestation by intra-rectal scanning, and from 50 days by external scanning. With advancing age the size of the fetus increased, and linear regressions of size on age gave residual standard deviations of 0.508 days for head diameter and 0.506 days for trunk diameter. It is concluded that this technique can be used to determine pregnancy with a high degree of accuracy from 30 days of gestation and to predict calving date from fetal measurements within the range 1.5 cm to 7 cm for head diameter or 0.5 cm to 8 cm for trunk diameter, corresponding to a fetal age range of 35 to 150 days.  相似文献   

6.
The testicles of 14 Landrace boars (7 at 9 months of age and 7 at 15 months of age) were measured and examined by routine physical examination. Semen analysis was done. The testicles were then examined and measured by B-mode ultrasonography. The ultrasonographic appearance and measurements were compared with the physical measurements and the semen analysis. Seminiferous epithelial area (SEA) data were obtained after the testicles were surgically removed. These data were compared with the ultrasonographic data and the other physical data. A correlation could not be found between semen analysis and either physical or ultrasonographic data or between SEA data and semen analysis. Significant differences were found between the 9-month-old and the 15-month-old boars relative to 5 measurements: SEA, tunica albuginea thickness, testicular diameter, testicular length, and epididymal diameter. A ratio of 4:1 was found between each of the average physical measurements (scrotal diameter, testicular-epididymal circumference, testicular-epididymal length) and ultrasonographic measurements of testicular diameter. A ratio of 2.6:1 was found between testicular diameter and epididymal tail diameter (cranial to caudal).  相似文献   

7.
OBJECTIVE: To compare corneal thickness, intraocular pressure, and optical corneal diameter in Rocky Mountain Horses with cornea globosa and those with clinically normal corneas. ANIMALS: 129 Rocky Mountain Horses. PROCEDURE: Ultrasonic pachymetry was used to measure corneal thickness. Applanation tonometry was used to measure intraocular pressure. A Jameson caliper was used to measure optical corneal diameter. RESULTS: The central and temporal peripheral portions of the cornea were significantly thicker in horses with cornea globosa than in horses with clinically normal corneas, but corneal thicknesses in the dorsal, ventral, and medial peripheral portions of the cornea were not significantly different between groups. There were no differences in corneal thickness between male and female horses or between right and left eyes. However, there was a positive correlation between age and corneal thickness. Intraocular pressure was not significantly different between horses with cornea globosa and those with clinically normal corneas, or between right and left eyes, or male and female horses. Optical corneal diameter for horses with cornea globosa was not significantly different from diameter for horses with clinically normal corneas, but optical corneal diameter was positively correlated with age. CONCLUSIONS AND CLINICAL RELEVANCE: Cornea globosa in Rocky Mountain Horses is not associated with increased intraocular pressure. Corneal thickness and optical corneal diameter increase with age in Rocky Mountain Horses.  相似文献   

8.
妊娠早期绵羊子宫和胎儿实测与超声探查比较   总被引:2,自引:0,他引:2  
用B超跟踪探查的9头妊娠母羊,分别于妊娠57、58、59、60、86、87、88、96和100d剖检,实测其于叶直径、胎儿冠一臀长、头长和胎儿主要内脏。结果发现,直径最大的子叶在妊娠86d,说明以测子叶直径来预测胎龄,只适用于妊娠86d以前;妊娠59d观察到有胃液,妊娠86、96d先后在直肠和结肠观察到有胎粪蓄积,96和100d在羊水和胃内发现有小粪球,说明此时已有排粪和吞咽反射;妊娠87和88d观察到膀胱有尿蓄积和睾丸降入阴囊。  相似文献   

9.
正阳三黄鸡产蛋初期蛋重、蛋形指数变化规律研究   总被引:1,自引:0,他引:1       下载免费PDF全文
 对正阳三黄鸡开产后70 d内的蛋重、蛋纵径、蛋横径进行了测量,研究正阳三黄鸡的蛋重、蛋纵径、蛋横径在开产初期的变化规律,并对产蛋初期蛋重、蛋纵径、蛋横径、蛋形指数进行相关分析,以及连产周期对蛋形指数的影响进行分析。结果表明:蛋重、蛋纵径、蛋横径在产蛋初期随着日龄的增加而增加,蛋形指数却随着日龄的增加而减小,且四者之间均存在着极显著的相关,而连产周期对蛋形指数的影响不显著.  相似文献   

10.
The diameter and area of the seminiferous tubules and the thickness of the germinal epithelium was measured in testes removed from clinically normal dogs of different breeds and mixed ages over a 24 month period which were presented for elective castration or euthanasia. Peripheral plasma testosterone concentrations were determined at the same time. There was no effect of the season of the year on the tubular diameter, thickness of germinal epithelium or tubular area. There was evidence of an effect of age upon tubular diameter and thickness of the germinal epithelium. Peripheral plasma testosterone concentrations were significantly higher in summer and autumn than in winter and spring, but age appeared to have no effect.  相似文献   

11.
本文系统分析了环境因素对辽宁绒山羊绒直径的影响、绒直径的遗传特点及其群体绒直径的分布情况。羊绒自根部至尖部逐渐变粗,尖部与根部绒直径相差3.31μm;体躯绒直径最小部位与最大部位差异为2.09μm;3周岁时绒直径最大,公羊平均绒直径比母羊高1.0μm;同一公羊雄性后代的绒直径比雌性后代平均高0.51μm;公羊年龄对后代具有显著的影响(P<0.05);绒直径的遗传力为0.421,与产绒量、体重的遗传相关分别为0.658和0.112。部分公羊的后代具有产绒量高、体重大而绒直径小的理想组合。在整个群体中26.40%的母羊和53.51%的公羊生产14.5μm以下的羊绒,9.6%的3周岁母羊和5.9%的3周岁公羊生产14.5μm以下的羊绒  相似文献   

12.
An experiment was conducted to describe the characteristics of Angora rabbit fiber using optical fiber diameter analyzer (OFDA). A total of 349 fleece samples were collected from 60 French Angora rabbits. Recorded measurements of OFDA were as follows: mean fiber diameter, CV of fiber diameter, comfort factor, spinning fineness, mean fiber curvature, SD of fiber curvature, mean opacity of fibers, percentage of medullated fibers, mean fiber diameter along the length, and SD of fiber diameter along the length. Comfort factor is the percentage of fibers less than or equal to 30 microns. The main effects included in the mixed model were fixed effects of group, harvest season, and age and a random effect of animal. Correlations among total fleece weight, compression, and OFDA measurements were calculated. Mean fiber diameter was lower than the fiber diameter along the length. Mean percentage of medullated fibers was very low and ranged from 0.1 to 7.3%. The mean comfort factor was 97.5% and ranged from 93.3 to 99.8%. The mean fiber curvature was 40.1 degrees/mm. The major changes in Angora fleece characteristics from 8 to 105 wk of age were an increase in fiber diameter, CV of fiber diameter, mean fiber diameter along the length and curvature, and a decrease in compression and comfort factor. The effect of harvest season was significant on some fiber characteristics. Mean fiber diameter and the mean fiber diameter along the length had a positive correlation with total fleece weight. The OFDA methodology is a method to evaluate fiber diameter, CV of fiber diameter, and bristle content through measuring of the comfort factor. However, OFDA is not adapted for measuring opacity or size of the medulla, or both, in Angora wool and needs a new definition or a special calibration. The spinning fineness should be redefined and adapted for Angora rabbits.  相似文献   

13.
Thirty-five young cats were studied by echocardiography from the 2nd to 12th weeks of life to analyze correlation between body weight, body surface area, age and heart rate with fourteen echocardiographic parameters. There was a positive linear correlation (r = 0.49-0.78) between the independent variables (body weight, body surface area, age) and left ventricular wall thickness and diameter, aortic diameter and left atrial diameter, whereas there was a negative correlation (r = -0.39 and r = -0.43) between the heart rate and left ventricular diameter during systole and diastole. No linear dependence of the fractional shortening, ejection fraction, percentage thickening of the interventricular septum and left ventricular posterior wall, LA/AO ratio, and the ratio IVSED/LVWED to the independent variables was observed.  相似文献   

14.
The different segments of the aorta were studied quantitatively in five age groups of chicken. It was observed that the widest diameter and the thickest media occur on the 56th day in each segment, except for the thoracic aorta, which had the widest diameter on the 42nd day and the thickest media on the 70th day. The percentage of the intima, media and the adventitia, as compared with the total wall thickness, was determined and it was found that this value was quite similar in age group, but the differences were significant from one segment to another. The ratio between the total wall thickness and the lumen diameter was also calculated in each segment.  相似文献   

15.
Two recombinant luteinizing hormone releasing hormone (LHRH) fusion proteins were evaluated for their effectiveness in suppression of testicular development and histology by injecting together. Recombinant fusion proteins, ovalbumin-LHRH-7 and thioredoxin-LHRH-7, were generated using recombinant DNA technology and expressed in E. Coli. Eleven ram lambs ranked by age and body weight were randomly assigned to receive either ovalbumin and thioredoxin recombinant protein mixture (control group, n = 5) or ovalbumin-LHRH-7 and thioredoxin-LHRH-7 recombinant fusion protein mixture, anti-LHRH vaccine, (immunization group, n = 6). Animals in each group were weaned at 17 wk of age and were injected (primary immunization) with either mixture at 18 wk of age. Both groups received a booster immunization 8 wks later (26 wk of age). Scrotal circumference, scrotal length, testicular diameter and testicular length were measured in both groups every other week. All animals were slaughtered at 36 wk of age. Immediately after slaughter, a small testicular tissue was taken and processed for histological examination. In the ram lambs in immunization group scrotal circumference and testicular diameter increased steadily until second booster and then remained as a plateau until the end of the experiment. The differences in scrotal circumferences and testicular diameter were significant between the two groups during the last three weeks of the study (p < 0.05). There were no differences in testicular and scrotal length throughout the study (p > 0.05). Seminiferous tubules lost their regular shape and were decreased in diameter in immunization group. Although a few spermatozoa were seen in some tubules, in general, there were atrophy of the seminiferous tubules and loss of spermatogenesis, nevertheless, it seemed that animals in this group were potentially fertile.  相似文献   

16.
五指山猪是中国特有的小型猪种,是作为人类实验模型的首选动物之一.为给五指山猪的品种保护和合理开发利用提供基础资料,试验采用解剖学和统计学方法,对不同日龄雌性五指山猪卵巢、输卵管和子宫进行了解剖测量,并对其数据进行了分析处理,探讨了其生长发育特点.结果表明,五指山猪卵巢长径、短径及厚度增长与日龄呈线性相关,其重量增长与日龄呈指数相关,而其指数随日龄增加呈先减后增的趋势;五指山猪输卵管长度和管径的增长与日龄呈线性相关,重量增长与日龄呈指数生长;五指山猪子宫体长度的生长与日龄呈线性生长模式,子宫体生长发育强度在70~110 d之间,其长度在1.093~11.557 cm之间.  相似文献   

17.
Single teased fibre studies were made on samples of the lateral palmar nerve from 16 horses of mixed age and size which had no evidence of neuromuscular disease. Significant proportions of abnormal fibres indicative of axonal degeneration/regeneration and demyelination/remyelination were identified. Measurements of internodal length and fibre diameter were made. Internodal length was shown to be related to fibre diameter, changes in this relationship being mainly influenced by the incidence of abnormal fibres rather than by the age of the horse. Information about the incidence of abnormal fibres in normal horses is required if findings in biopsy material are to be interpreted correctly.  相似文献   

18.
This study was designed to examine the effects of age and developmental stage of in vitro‐produced bovine embryos on the cell number of the embryos and to investigate the correlation between the cell number and diameter in the embryos. The diameter and cell number in blastocysts and expanded blastocysts collected on days 7–9 after in vitro fertilization (IVF) were examined. Although the diameters of the blastocysts collected on days 7 and 8 after IVF were smaller than those of the expanded blastocysts collected on day 9, the cell number in both types of embryos was similar. The cell numbers of the blastocysts and expanded blastocysts decreased with increasing embryo age. There were positive correlations between the cell number and diameter in bovine embryos at each stage collected on each day after IVF. However, the value of the correlation coefficient in the day‐9 expanded blastocyst group tended to be higher than that in the other groups. These results indicate that the cell number of in vitro‐produced embryos is affected by the embryonic stage and age. The diameter of the embryo may be potentially used for the viability testing of the expanded blastocysts collected on day 9 after IVF.  相似文献   

19.
为了研究蛋形指数对拉萨白鸡种蛋孵化效果的影响,在相同孵化条件下,选用3世代47周龄拉萨白鸡种蛋,按蛋形指数分组进行孵化,并对蛋形指数与孵化效果的相关性进行了分析。结果表明,蛋形指数(横径/纵径)在0.68~0.72时,0胚龄蛋重、纵径均值、头照(第11日胚龄)蛋重、二照(第20日胚龄)蛋重最大,分别为:(51.92±5.27)g、(57.71±1.97)mm、(48.95±4.67)g、(45.47±3.97)g;蛋形指数(横径/纵径)在0.73~0.77时,入孵蛋孵化率、受精蛋孵化率和雏鸡的初生重最大,分别为:82.65%、86.60%、(36.31±4.71)g;蛋形指数(横径/纵径)在0.78~0.82时,头照(第11日胚龄)失重、头照(第11日胚龄)失重率、二照(第20日胚龄)失重、二照(第20日胚龄)失重率最大,分别为:(3.35±0.93)g、(6.64±1.54)%、(6.70±1.47)g、(13.47±2.56)%;蛋形指数(横径/纵径)在0.83~0.87时,橫径均值、受精率、健雏率、雏鸡初生重占入孵蛋重的百分比最大,分别为:(42.82±1.23)mm、97.26%、95.96%、(70.23±3.58)%;雏鸡初生重与雏鸡初生重占入孵蛋重的百分比呈极显著正相关(P<0.01)。该研究为拉萨白鸡今后的选育提供了理论依据。  相似文献   

20.
In the present study, the relationship of normal adrenal dimensions with weight, aortic diameter, age and sex was evaluated. Moreover, a formula for estimating the normal dimensions of adrenal gland was provided. Thirty‐two intact adult dogs that were considered healthy based on history, physical examination, routine blood works and specific adrenal tests as well as absence of any abnormal ultrasonographic findings were included. Adrenal glands and abdominal aorta were imaged in the sagittal plane by ultrasound. Length, maximal height of the cranial and caudal poles, area and circumference of the left and right adrenal glands and also the internal diameter of the abdominal aorta were measured. Analysis showed that there is a positive correlation between the adrenal gland dimensions and weight and aortic diameter. The ratio of adrenal gland dimensions and the aortic diameter was calculated, but this ratio showed a great amount of variability in tandem with a significant correlation to the weight; Meaning that the ratio of the adrenal gland dimensions to the aortic diameter was not a reliable index for evaluating the size of the normal adrenal gland in animals with different weights. Therefore, we used the weight along with adrenal measurements in a linear regression model, and then, we were able to estimate the adrenal gland dimensions in different weights. Knowing the relationship of normal adrenal dimensions with the indices such as weight, age, sex and diameter of abdominal aorta can help the clinicians to diagnose the adrenal gland diseases.  相似文献   

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