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1.
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.  相似文献   

2.
In keeping of pets accessories play an important role. They serve to improve the conditions of pet keeping or even help to make it possible at all. Beyond that, accessories enrich activity of the animals and thus may increase their well-being. But accessories can endanger health and life of the pets due to deficient quality or due to inadequate use. This paper demonstrates the sources of danger potentially arising from accessories by pointing out examples. On the other hand exemplary paraphernalia and ways of pet keeping are presented which are qualified to increase well-being of the pets and to avoid physical impairment.  相似文献   

3.
The effect of different rates of induction of carbon dioxide anaesthesia on the time to loss of consciousness was investigated in broilers and hens. In experiment 1, 24 and 17 broilers, respectively, were exposed to 45 per cent carbon dioxide within 8 or 18 seconds (accession time). In experiment 2, 18 to 20 broilers and hens were exposed to either 35, 45, 55 or 65 per cent carbon dioxide within 8 seconds. The results indicated that, in general, the rate of accession is more critical than the final concentration of carbon dioxide; however, in 35 per cent carbon dioxide an exposure time of longer than 5 minutes is required to kill the birds. The time to sustained eye closure, time to onset of clonic and tonic convulsions and the duration of convulsive episodes were shorter in broilers than in hens. It is suggested that under commercial situations a final concentration of 55 per cent carbon dioxide would be suitable for killing broilers and hens.  相似文献   

4.
Cats with induced sterile abscesses developed a hematologic disorder consistent with anemia of inflammation. Serum iron concentrations decreased while the abscess was present, but erythropoietin concentrations did not change significantly. Cobalt administration to control (healthy) cats resulted in polycythemia, reticulocytosis, and hyperferremia. Cats with abscesses responded to cobalt similarly; however, magnitudes of the polycythemia and reticulocytosis were less. Constant infusion of ferric citrate (IV) into cats with sterile abscesses maintained serum iron concentration in the normal to high range. The iron infusion did not prevent the anemia, but did enable the bone marrow to respond to the anemia.  相似文献   

5.
REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.  相似文献   

6.
The aims of this study were to assess the precision of the estimates of the time of ovulation derived by various methods, and to define the most appropriate methods for the determination of the optimal time for insemination of bitches with fresh semen (artificial insemination or natural mating), or with frozen-thawed semen. In 11 Labrador bitches, ovulation was estimated (plasma LH surge + 48 h) to occur 9 to 20 d after the start of the cycle, 0 to +4 d after the onset of positive postural reflexes (2 bitches showed no positive postural reflexes), -4 to +7 d after reaching a vaginal cytological eosinophilic index (EI) of 100%, over a range of 2.5 to 5.5 d based on plasma progesterone concentrations of 4 to 10 ng/ml, over a range of 2 to 3 or 4 d based on 2 indirect methods of estimating the time of the plasma LH surge from plasma progesterone concentrations. Assuming fertilisation occurs 2 to 3 d after ovulation, these findings indicate that for fresh semen (with an estimated lifespan of greater than 4 days) an appropriate procedure would be to inseminate/mate on the day after the onset of positive postural reflexes; then 3 days later. For bitches not showing positive postural reflexes, insemination should occur when the vaginal EI = 90% and then each 3 d until day 1 of dioestrus (D1). For frozen-thawed semen (with a lifespan of less than 24 h) insemination should occur 4 to 5 d after the plasma LH surge.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Background: Owners' perceptions and priorities regarding quality of life (QoL) are important considerations given the unknown efficacy of many commonly administered medications, stress of hospital visits, difficulties providing home care, and personal choices including euthanasia. Objective: To describe the relative importance of quality versus quantity of life to owners of cats with heart disease. Animals: Two hundred and thirty‐nine cats with heart disease. Methods: Prospective questionnaire‐based clinical study. Cat owners completed a questionnaire to identify important parameters when assessing their cat's QoL, the relative importance of quality versus quantity of life, and willingness to trade survival time for QoL. Variables associated with these parameters were evaluated with multivariate analyses. Results: Appetite, owner interaction, sleep patterns, and litterbox habits were deemed important to QoL. Concern over pet suffering was significantly greater than concern over life expectancy. Ninety‐three percent of owners were willing to trade survival time for good QoL; 57% of these were willing to trade up to 6 months. On multivariate analysis, the only factor significantly (P= .002) associated with willingness to trade 6 months was study site. Owner concern regarding stress of administering medications at home increased with number and frequency of medications. Conclusions and Clinical Relevance: These results indicated that QoL is more important to owners of cats with heart disease than longevity. The various priorities and concerns of cat owners should be taken into account in order to provide optimal care.  相似文献   

8.
莱克多巴胺属于β-兴奋剂,在动物性产品中残留量过高会危害人类健康。本试验采用酶联免疫法来检测甘肃部分地区猪肉中莱克多巴胺的残留量,根据酶联免疫试剂盒检测出猪肉中莱克多巴胺的检出限为24 μg/kg,以莱克多巴胺的6种标准品测得莱克多巴胺的标准曲线,以此检测甘肃部分地区猪肉中莱克多巴胺的残留量是否超出检出限,并分析不同地方莱克多巴胺残留量存在差异性的原因。  相似文献   

9.
Lungs from 48 feedlot cattle that had died from bacterial pneumonia were examined grossly and microscopically. Criteria based on microscopic lesions were adopted to age these pneumonias. In 38 cases, pneumonic lesions were of relatively uniform age throughout the affected tissue. In eight other cases, the presence of older lesions confined to one or two lobes suggested a previous episode of pneumonia. The aging criteria adopted were in agreement with the duration of the observed clinical signs in 26 cases. In 13 other cases, the pneumonia was estimated to be of longer duration than suggested by the history, whereas in the remaining nine cases, it was estimated to be more recent. Areas of tan discoloration of the parenchyma surrounded by white or yellow borders were considered the best areas to examine microscopically since they offered the best chances of revealing necrosis and fibrosis, the main lesions used to age the pneumonia.  相似文献   

10.
国家新品种药物研究开发的核心内容是生物技术制药和药物现代化。而《生物技术制药》课程在生物专业类大学本科人才培养方案中开设的目的是为培养制药理论与生产实践相结合的高素质的技能型人才。由于该课程开设的时间相对较晚,又是一门新兴学科,以往传统的教育模式直接应用到该课程上就显得有一定的滞后性,所以有必要针对《生物技术制药》课程的特色及其学科特点进行教学方法与教学手段改革的探索。  相似文献   

11.
Mulesing is traditionally performed on approximately 80% of Merino wool-producing sheep in Australia. Mulesing produces a stress response that persists for 24 to 48 hours. Behavioural changes indicative of pain and discomfort resolve within 24 and 48 hours, respectively. Reductions in weight gain may persist for 14 days. The acute stress response to mulesing has been shown to be similar to that produced by shearing, castration and mild flystrike, but mulesing has a longer duration of response (24 to 48 hours) than shearing (1 hour) or knife castration (8 to 24 hours), whereas flystrike response persists for the duration of infection. Theoretically, if mulesing were not used, with Merino sheep of existing genetics, increased chemical use and flock inspections could keep flystrike rates to approximately equivalent to present levels in some production systems. Increased handling events for chemical preventative application would represent a mild stressor for sheep, but cumulatively not more than that of mulesing. If producers were able and prepared to sufficiently increase resources into alternative anti-flystrike methods, then the welfare of Merino sheep would probably be equivalent or better to that of today. If constraints such as property size or finances dictate a sub-optimal level of flystrike prevention and treatment, then animal welfare will unquestionably be worse. The result of that equation would depend on individual flock managers, the physical characteristics of their production system, the profitability of their business, and seasonal variations in flystrike risk. It is likely that there would be some occasions when flystrike would increase. This highlights the need for alternative strategies, such as genetic selection, to reduce the susceptibility of Australian Merino sheep to flystrike.  相似文献   

12.
Employing the turnover of a dairy-cow herd with primiparas to control infectious mastitis is beneficial because young dairy cows, as a rule free of inflammations of the mammary gland, are not included among dairy cows already infected or suspected of being infected and so it is possible to form groups of dairy cows free of mastitis. For this intention an agricultural enterprise was chosen in potato production region I. In the given period 316 to 336 dairy cows of Bohemian Spotted breed were followed. To express the impact of the infection on the milk efficiency and to draw economic conclusions on the efficiency of treating infectious mastitis we observed the total milk yield of the different dairy cows in one lactation. In the given enterprise unsuccessful treatment of an infected dairy cow in three lactations resulted in a total loss of 4,648 Kcs. Therefore from the economic aspect it appears to be profitable to replace productive, but ill, older dairy cows by healthy first-calvers because the negative effect of the mastitis on the production of milk increases with every successive lactation.  相似文献   

13.
The use of an electric collar for training dogs is fundamentally forbidden. The verdict of the Federal German Administrative Court dated February 23, 2006 (ref. 3 C 14.05) provides legal clarity and indicates the approach to be taken to enable exceptions from the fundamental ban on electric collars. It is particularly to prevent the misuse of electric collars in the interests of animal welfare that federal legislation should further develop the approach specified in 1998 by including Article 3, No. 11 of the German act on the prevention of cruelty to animals (TierSchG). In this context, it is recommended to continue intensive specialist debate on the question of whether and, where applicable, to what extent the use of electric collars may be permitted, e.g. within the context of training dogs.  相似文献   

14.
首先进行了李斯特氏菌因子血清的研制,制备出了可对所有李斯特氏菌分型的 15 个 O 抗原因子和4 个 H 抗原因子的因子血清。利用复合因子血清的多克隆抗体包被磁性球,对食品中的单核细胞增多性李斯特氏菌进行免疫磁性分离,并与 P C R 方法相结合,建立了检测食品中单核细胞增多性李斯特氏菌的 M I P A方法(免疫磁性分离—聚合酶链反应方法,m agn etic im m unopolym erase chain reaction assay)。对菌液、模拟样品的检测表明,本方法能够有效地克服食品基质、培养基成分和杂菌对 P C R 检验的干扰作用。食品样品在 E B增菌液中增菌 12 h 后,检测的敏感度达 5 C F U/m L,可以在 20 h 内完成检测。本方法对实际食品样品的检测结果,与国家标准检验方法检测的结果一致。  相似文献   

15.
We investigated the influence of age of exposure to a specific forage on its consumption by young sheep both during and after that exposure. Prior exposure to the shrub Cercocarpus montanus enhanced subsequent consumption (P less than or equal to .05) of that shrub by lambs and yearlings during two experiments in consecutive years. Effects of prior exposure persisted as long as 9 mo without intervening exposure. Age of exposure influenced consumption in lambs both during the period of exposure (P less than or equal to .0001) and during feeding trials following exposure (P less than or equal to .07) in Exp. 1. Lambs exposed at 1 to 5 wk of age, when they are nonruminant and normally are dependent on the dam, browsed less of the time while at the shrub (P less than or equal to .02) and consumed less of the shrub (P less than .02) at a slower rate (P less than or equal to .03) than did lambs exposed at older ages. Lambs exposed at 4 to 8 wk of age, a period corresponding to the transition from nonruminant to ruminant digestion, consumed more shrub following exposure than did lambs exposed at younger or older ages (P less than equal to .05, unprotected least significant differences test). In Exp. 2, which compared naive yearlings with the experienced yearlings exposed as lambs in Exp. 1 the previous year, age of exposure did not influence consumption by yearling sheep following exposure; however, the number of months that had elapsed from the period of exposure varied from 0 to 13 among experimental groups and may have confounded results. Learning of forages appeared poor among nonruminant lambs; data were inconclusive concerning the efficiency of learning of lambs in the transition to ruminant digestion.  相似文献   

16.
杀虫剂溴氰菊酯对野桑蚕和家蚕的毒力比较   总被引:12,自引:8,他引:4  
基于了解野桑蚕(Bombyxmandarina)和家蚕(Bombyxmori)对农用杀虫剂溴氰菊酯的抗药性差异,采用点滴法和浸叶法测定了溴氰菊酯对野桑蚕和家蚕的毒力,结果其毒力基本一致。野桑蚕和家蚕对溴氰菊酯的敏感度均较高,LD50在0.027~0.429 ng/头之间,但吴江野桑蚕、启东野桑蚕和苏大野桑蚕的抗药性较相对敏感的家蚕品种大造、菁松、皓月强10.11~15.89倍,较家蚕品种L11强4.37倍。  相似文献   

17.
Light-microscope and electron-microscope studies of a coccidial organism found in the bursa of Fabricius from 3 chickens clearly established the parasite as belonging to the family Cryptosporiidae. Hyperplasia and heterophil infiltration were associated with the presence of organisms attached to the microvillus border of epithelial cells lining the plicae of the bursa of Fabricius. Although there were no clinical signs or gross lesions common to the 3 cases described, all had similar histologic lesions in the epithelium lining the bursa of Fabricius.  相似文献   

18.
The Society of Friends of the University of Veterinary Medicine Hannover was established in 1926, in times of severe economical distress. According to its statutes its main purpose from the beginning was to complement the governmental budget of the University. During its 80 years of existence the so called "Friendly Society" has contributed to overcome many financial shortages in research, clinics and institutes. In addition it supported veterinary students in need. Some aspects of the Society's history and activities will be communicated.  相似文献   

19.
The high level of the cultural confidence is essential to instruct college students to integrate individual dream into Chinese dream,which is also the spirit source to transmit positive social energy.However,the current part of college students lack of cultural self-confidence,the loss display mainly that they are cognitive deficiencies on the national traditional culture,they blind recognition of western culture,they do not pay attention to contemporary Chinese advanced culture.  相似文献   

20.
In a set of mares of English Thoroughbred horse of the Napajedla stock the gravidity length in the time period from 1880 to 1972 was evaluated. The variability of the gravidity length was evaluated in sets which were put together by combination of two age groups with a division of the studied time period into ten-year stages. Variance and sample means of the gravidity lengths in these sub-groups are significantly different in the period under study. In order to eliminate the action of non-genetic influences qualifying the variability of the gravidity length, and to increase the objectivity of their evaluation it is proposed not to calculate with absolute values of the gravidity length, but on the contrary with transformed values: (xi - x) divided by s which would be computed for corresponding year of the foaling period. Another methodical approach to exclude the variability of the gravidity length depending on seasonal influences was based on the use of correction factors which were determined for individual months of foaling, on the basis of the sinusoid form of the curve of the gravidity length in the course of the calendar year. When observing the influence of the age of sires on the gravidity length, the shortening of the gravidity length in dependence on their higher age has been suggested, however this relation was significant only sporadically. The submitted work is a part of a larger theme referring, to the reproduction of horses.  相似文献   

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