排序方式： 共有84条查询结果，搜索用时 15 毫秒
61.
近年来,不同家畜饲料原料最佳粉碎粒度的研究引起了畜牧业工作者的极大关注.目前,关于准确调换心烦意乱原料的粉碎粒度以使家畜生产怀能达到最佳的问题,在科技刊物上已有许多报道. 相似文献
62.
Abstract CASE HISTORY: In 2008, six lambs within a flock of Dorpercross sheep were born with musculoskeletal and neurological disease. Clinical signs included hindlimb weakness, and urinary incontinence. CLINICAL FINDINGS: All lambs had focal, inverted areas of alopecic skin over the caudal sacrum, and short, often kinked tails. Four affected lambs were subject to euthanasia, and necropsied. On gross examination, the arches of sacral vertebrae were absent, and spinal nerves and meninges were adherent to the overlying subcutis. Other gross lesions included narrow, elongated skulls, herniation of the occipital lobes into the caudal fossas, hydrocephalus, and syringomyelia. One lamb had coning of the cerebellar vermis, but cerebellar herniation through the foramen magnum was not identified. DIAGNOSIS: Spina bifida, with associated malformations of the central nervous system. CLINICAL RELEVANCE: Examination of breeding records suggested either an autosomal recessive or partially penetrant autosomal dominant pattern of inheritance. Because of the associated tail lesions it is proposed that the pathogenesis of this syndrome involves a defect in development of the tail bud (secondary neurulation), that tethering of the spinal cord resulted in the clinical signs, and abnormal pressure of the cerebral spinal fluid resulted in the defects in the skull and brain. 相似文献
63.
MJ Voorhorst JC van Brederode CHJ Albers‐Wolthers J de Gier AC Schaefers‐Okkens 《Reproduction in domestic animals》2013,48(5):840-843
Subinvolution of placental sites (SIPS) is the major cause of persistent sanguineous vaginal discharge after parturition in the bitch. Spontaneous remission is common but may take several months, and hence, medical therapy to end the discharge is often requested. In this retrospective study, we evaluated the effect of treatment for SIPS with low oral doses of a progestagen. Nine bitches with SIPS, but otherwise clinically healthy, were found in the computer database of the Department of Clinical Sciences of Companion Animals. Seven of these bitches were treated with low oral doses of a progestagen (megestrol acetate, 0.1 mg/kg body weight (bw) once daily for the 1st week, then 0.05 mg/kg bw once daily for the 2nd week). The other two bitches were untreated. Treatment results were evaluated by a telephone questionnaire. Progestagen treatment was successful in all of the treated dogs; sanguineous vaginal discharge stopped within the treatment period. One of the two untreated dogs remained symptomatic until the next oestrus, approximately 120 days after parturition, and the other remained symptomatic until 6 weeks before the start of the next pro‐oestrus, 270 days after parturition. No side effects of the progestagen treatment were observed. Subsequent gestations, parturitions and puerperal periods of 5 mated bitches were uneventful. One bitch did not become pregnant after mating. In conclusion, the results of this study indicate that oral administration of low doses of progestagen for 2 weeks is effective in stopping persistent sanguineous vaginal discharge in bitches with SIPS, with neither side effects nor reduced subsequent fertility. 相似文献
64.
Determining the bioavailability of contaminants and assessing the quality of sediments 总被引：1，自引：1，他引：0
Stephen AC Marklevitz Elizabete Almeida Joanna Flemming Jocelyne Hellou 《Journal of Soils and Sediments》2008,8(2):86-91
Background, Aims and Scope Our study determined the role of light, aeration, grain size, amount of sediments and of water, density of animals and presence
of additional food on the movement of Ilyanassa obsoleta. Spiked relative to reference sediments were also tested for avoidance or preference by the mud snails. Our goal was to develop
exposure conditions to be used in future assessment studies of the environmental quality of sediments inhabited by mud snails.
The behavioural response of the snails towards different concentrations of contaminated Halifax Harbour sediments placed in
one half of a tank relative to reference sediments in the other half is examined in Part 2 and a chemical link investigated.
Methods Animals were exposed in 7 L aquaria at 12°C to their native sediments placed in one or two halves of a tank and the effect
due to the presence of a light source, air bubbles, sediment grain size, added algae examined relative to the snails’ behaviour.
Preference or avoidance of one half of a tank relative to the second half, the immersed or dry glass surface represented the
various media to be chosen by snails. After choosing the optimum set up, exposures were performed in triplicate, under slightly
differing initial placement of the snails to compare means and variability in the results. Three specific biogenic chemicals,
cholesterol, coprostanol and a fatty acid methyl ester (FAME) were spiked at 0.002, 0.01, 0.05, 0.25 and 1.2 mg/g, dry weight
of sediment. A hexane, dichloromethane and methanol extract of harbour sediment were also spiked in reference sediments. In
all cases, the location of the snails was recorded over a period extending up to 96 hrs.
Results Twenty snails exposed during a 72 hrs period in commercial 7 L tanks containing 50 g of sediments (wet weight) in the bottom
half of a tank filled half way with seawater represented the chosen conditions to test the avoidance/preference behaviour
of snails for part of a tank. The presence of additional food on sediments attracted snails within 24 hrs of exposure.
Discussion A general lack of preference was indicated in exposures to three biologically derived compounds spiked in reference sediments,
i.e. a C-18 FAME, cholesterol and coprostanol. The repelling properties of a harbour sediment extract pointed to a role for
non polar chemicals.
Conclusions It is proposed that behaviour reflects a balance between the repelling effects of contaminants and the attractive value of
food. The present study provides a robust green assessment tool that is easy to set up to assess the quality of sediments.
Recommendations and Perspectives The interpretation of field observations regarding the abundance of animals during environmental assessments must consider
both nutritional and toxicological causes. Additional laboratory exposures are needed to determine which chemicals play a
role in the field. 相似文献
65.
WL Vianna DG Bruno A Namindome AC de Campos Rosseto RC Barnabé A de Sant'' Anna Moretti 《Reproduction in domestic animals》2007,42(5):466-470
The correct measurement of spermatic concentration in boar semen is one of the basic tasks routinely performed at the Swine Artificial Insemination Center (CIAS). This article explains two experiments whose objectives were: Experiment 1: This trial had two objectives: (1) to evaluate the precision of the spermdensimeter (SPM) with relation to the Neubauer count chamber (CN) which is considered the standard technique in the field and (2) to correct the scale on the SPM table. Experiment 2: This trial also had two objectives: (1) to evaluate the time and repetitions required in the SPM and (2) to compare the SPM adjusted table produced in Expt 1 with the SPM standard table. The methods in Expt 1 were used to measure total spermatic concentration in 141 boar ejaculates. The average spermatic concentrations (10(6) spermatozoids/ml) and average dose number were 229.1 and 22.6 for CN, and 283.6 and 28.0 for SPM. These results indicate that the SPM has a tendency to overestimate spermatic concentration with relation to the CN. The SPM produced a smaller coefficient of variation and needed lesser examination time than the CN (p < 0.05). The SPM adjusted table created in Expt 1 produced similar results as the SPM and CN standard tables (2.96 billion live spermatozoids/dose vs 2.36 billion live spermatozoids/dose). Incorporation and evaluation of supplemental data from other CIAS regarding the use of the SPM adjusted table in the field entitled 'Adjusted Table for Karras Spermdensimeter LPS-FMVZ-USP' would be valuable to prove its efficiency. 相似文献
66.
In the bitch, progression from early to late anoestrus is characterized by a higher amplitude and a larger number of gonadotrophin-releasing hormone (GnRH) pulses generated by the hypothalamus, an increase in the sensitivity of the pituitary to GnRH, and an increase in ovarian responsiveness to gonadotrophins. An increase in basal plasma follicle-stimulating hormone (FSH) concentration is a critical event required for initiation of folliculogenesis. A period of increased luteinizing hormone pulsatility has been reported shortly before the onset of pro-oestrus. Apart from these changes in the hypothalamic-pituitary-ovarian axis, there is also involvement of dopaminergic influences in the initiation of a new follicular phase in the bitch. Administration of the dopamine-agonists bromocriptine and cabergoline shortens the anoestrus and is associated with a decrease in the plasma prolactin concentration, suggesting that the shortened anoestrus is the result of suppression of prolactin secretion. Yet, the anoestrus is not shortened in bitches treated with metergoline, a drug, which in a low dosage lowers the plasma prolactin concentration via a serotonin-antagonistic pathway. In addition, under physiological conditions low plasma prolactin concentrations are found during the entire anoestrus. Furthermore, a low dosage of bromocriptine, insufficient to cause a decrease in the plasma prolactin concentration, prematurely induces folliculogenesis. These observations indicate that not the decrease in the plasma prolactin concentration, but another dopamine-agonistic influence plays a critical role in the transition to a new follicular phase. The dopamine-agonist induced shortening of the anoestrus is associated with a rapid rise in the basal plasma FSH concentration, similar to what is observed during the physiological late anoestrus. This observation underlines the importance of an increase in the circulating plasma FSH concentration in the initiation of folliculogenesis in the bitch. 相似文献
67.
The ability of fallow does to rear fawns to weaning age was examined in a group of 243 adult does of known age (Group 1) and 509 adult does of unknown age (Group 2). All does had between 1 and 8 opportunities to rear fawns. There was an increasing proportion of does that failed to rear a fawn to weaning age as the number of rearing opportunities increased, although most does (93.6%) only failed on one occasion. A small percentage of does in groups 1 and 2 failed repeatedly to rear fawns to weaning. At slaughter, the presumed causes of failure in chronic non-breeders included pyometron, cystic ovaries, cervical cysts, a vulval neoplasm and salpingitis. The overall rearing success of both groups of deer was 82.4% and there was no consistent pattern of rearing failure relating to parity or previous rearing history. 相似文献
68.
AIMS: To assess the attitude of dairy farm consultants to the role of veterinarians on dairy farms and whether they viewed veterinary advice as impartial, free from commercial bias and central to farm productivity and profitability.
METHODS: A telephone survey was commissioned in September 2014 of 36 full-time farm consultants in the Canterbury and Otago region of New Zealand using a pre-prepared questionnaire to explore their attitudes towards the veterinary profession. Of those approached, 25 completed the survey.
RESULTS: The consultants surveyed agreed or strongly agreed (21/23) that they were the custodians of animal health expenditure on farms, which was seen as an expense to be controlled (19/25 agreed or strongly agreed). This view was held more strongly (9/9 agreed or strongly agreed) by consultants with >5 years’ professional experience, compared to 10/16 consultants with ≤5 years’ experience. Most consultants (24/25) disagreed that they did not respect veterinary advice, but agreed (24/25) that veterinarians almost always had a vested interest in the advice that they gave. The role of veterinarians was seen by respondents to be mainly treatment of sick animals (22/25) and provision of animal health products (24/25), but not in maximising farm profitability (selected by 8/25 respondents). Consultants viewed their own roles as providing advice on the influence of animal health on farm profitability (21/25), nutrition (22/25) and reproduction (20/25). Most respondents (21/25) stated that reducing disease and animal health issues was important, but they (21/25) also identified a reduction in farm animal health expenditure as a measure of success. Only 7/25 consultants felt that they should work in partnership with veterinarians.
CONCLUSIONS: This was a small scale study from one region of New Zealand but it indicates that consultants are ambivalent about the role and value of working more closely with veterinarians, and about the benefit that veterinary intervention may bring to a farm’s profitability.
CLINICAL RELEVANCE: More successful veterinary involvement on dairy farms will follow from a better understanding of how other rural professionals are involved in the farm’s management and in meeting the individual farmer’s goals and motivations. 相似文献
69.
AC Morini NCG Pieri KCS Roballo DS Martins CE Ambrósio JC Morini Junior PO Favaron AHH Minervino FVT Pereira MA Miglino 《Reproduction in domestic animals》2016,51(4):509-514
Many researches describe the embryonic developmental features in domestic animals; however, in farm animals, they are scarce. Most farm animal studies are related to assisted reproduction and embryos transfer techniques. But, morphological features and size measure to estimate the age gestation are rarely reported in literature. Thus, in this study, we described the developmental changes in the bubaline (Bubalus bubali) concepts from 21 to 60 days of gestation. Our results revealed that buffalo embryos similar morphological characteristics similar to other mammalian species. Also, similarities between bovine and bubaline persist; except on foetal stages when buffalos have a faster development than bovine. Therefore, buffalo's gestation period exhibits some varieties and accurate embryo age is more difficult. Yet, when we use a combination of the crown–rump, macroscopic analysis and alizarin red, it is possible to describe better the whole embryogenesis stages of the buffalo and which can contribute for future reproduction researches and applications in veterinary practice. 相似文献
70.