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361.
At 11 to 13 d after insemination, 1028 dairy cows on 19 farms were given an intramuscular injection of 10 micrograms of the GnRH analogue buserelin. Their reproductive performance was compared to 1022 control cows receiving a placebo. The GnRH analogue-treated cows had fewer short interoestrous intervals compared to the control cows, but there were no significant differences in pregnancy rates to either the insemination preceding or following treatment, in calving to conception interval, or to percent pregnant by the end of mating. There were no differences between treatments in herds of high, average or low pregnancy rate, in 2-year-old cows or cows greater than 2-years-old and in cows calved 40 d or less, or greater than 40 d. The use of 10 micrograms of the GnRH analogue, buserelin, 11 to 13 d after insemination, cannot be recommended as a method of improving reproductive performance in dairy herds. 相似文献
362.
The records of 1630 mare years from 6 Thoroughbred stud farms in south eastern Australia were analysed for the years 1981 to 1986. Overall pregnancy and foaling rates were 83.9% and 69.3%, respectively. When calculated per served oestrous cycle, pregnancy and foaling rates were 54.7% and 43.1%, respectively. Pregnancy and foaling rates were higher (P < 0.001) for mares 3 to 10 years of age than for older mares. There was no difference in the pregnancy rates of maiden, barren and foaling mares. The foaling rate was significantly higher (P < 0.001) in mares that became pregnant during the first served oestrous cycle (77.8%) than in mares that needed two served oestrous cycles to become pregnant (65.4%). Of all diagnosed pregnancies, 19.5% were not completed. Pregnancy loss was lower (P < 0.05) in maiden (12.4%) than in barren (19.7%) or foaling (20.9%) mares. Twins were diagnosed in 7.8% of all pregnancies. If one conceptus was lost without external interference, 84.1% of pregnancies went to term. If one conceptus was manually crushed, 55.9% of pregnancies were maintained. If prostaglandin was used to terminate twin pregnancies, 60% of mares so treated produced foals the following year. 相似文献
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365.
A 19-month-old cat investigated because of depression, anorexia, polyuria, and polydipsia was found to have hepatomegaly, retinal haemorrhages, and distended tortuous retinal veins. Prolonged bleeding occurred after venipuncture, and serum was hyperviscous due to an immunoglobulin M monoclonal gammopathy. Prothrombin and activated partial thromboplastin times were prolonged, thrombin clotting time was only slightly prolonged and the activities of coagulation factors VII, VIII and IX were normal. The cat died suddenly before the origin of the immunoglobulin could be determined. Hepatic plasmacytoid lymphosarcoma was found at post-mortem examination. The pathophysiology of hyperviscosity syndrome is discussed and the observations in this cat are compared with those reported in the dog. 相似文献
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367.
A radioimmunoassay for canine serum trypsin-like immunoreactivity (TLI) has been developed and evaluated for use in the diagnosis of exocrine pancreatic insufficiency (EPI). The maximum fasting TLI concentration in 14 dogs with EPI was 1.8 μg/l, compared with a minimum value of 7.0 μg/l in a control group of 75 dogs. The measurement of serum TLI therefore provides a sensitive test for the diagnosis of EPI in the dog. 相似文献
368.
E. D. WILLIAMS 《Weed Research》1973,13(1):24-41
Summary. The growth of Agropyron repens seedlings, or of clones derived from them, raised from seeds collected from different areas was compared; the growth of seedlings raised from seeds from single spikes and from seeds of a cross of two clones was also compared.
The number and length of shoots and the amount of rhizome produced differed between seedlings from different areas. Seedlings with a large weight of rhizomes often had a small weight of shoots. Many of the differences found between seedlings from different areas were confirmed by comparing clones established from some of them. Comparisons of both seedlings and clones showed that the percentage of shoots that developed spikes differed between genotypes; clones with the least weight of rhizome tended to have most weight of spikes. Large variations also occurred between clones established from seedlings from a given area, particularly in the way their dry weight was partitioned between primary and secondary shoots and in the time the spikes emerged.
The amount of rhizome per seedling varied greatly between seedlings from seeds from single spikes and from seeds from a cross of two clones. There was some evidence of a negative correlation between per cent shoot and per cent rhizome dry weight with seedlings from single spikes and between number of shoots and number of rhizomes per seedling with seedlings from a cross of two clones.
Variation en croissance de plantules issues de semences et de clones d' Agropyron repens (L) Beauv. 相似文献
The number and length of shoots and the amount of rhizome produced differed between seedlings from different areas. Seedlings with a large weight of rhizomes often had a small weight of shoots. Many of the differences found between seedlings from different areas were confirmed by comparing clones established from some of them. Comparisons of both seedlings and clones showed that the percentage of shoots that developed spikes differed between genotypes; clones with the least weight of rhizome tended to have most weight of spikes. Large variations also occurred between clones established from seedlings from a given area, particularly in the way their dry weight was partitioned between primary and secondary shoots and in the time the spikes emerged.
The amount of rhizome per seedling varied greatly between seedlings from seeds from single spikes and from seeds from a cross of two clones. There was some evidence of a negative correlation between per cent shoot and per cent rhizome dry weight with seedlings from single spikes and between number of shoots and number of rhizomes per seedling with seedlings from a cross of two clones.
Variation en croissance de plantules issues de semences et de clones d' Agropyron repens (L) Beauv. 相似文献
369.
An ultrasound assessment of follicle turnover following two different protocols for synchronization of oestrus and ovulation, as well as an assessment of achieved synchronization between ovulation and AI and conception rates in nulliparous and pluriparous buffaloes were carried out during months of increasing day length. Nulliparous buffaloes (n = 30) were subjected only to Ovsynch protocol whereas pluriparous buffaloes (n = 31) were assigned to Ovsynch (n = 14) or to PRID-pregnant mare serum gonadotrophin (PMSG) (n = 17) protocol according to the presence of functional CL confirming cyclic and acyclic conditions. Ultrasound examination of ovarian follicular dynamics at critical days in the course of synchronization treatments was employed to monitor the fate of the largest available follicles at the beginning of treatments. Such available dominant follicle would persist throughout the protocol as ovulating follicle (no-follicle shift) or would regress giving way to a new follicle to become dominant and ovulate (follicle shift). Furthermore, ultrasound monitoring would determine the degree of synchronization of ovulation and final outcome represented by pregnancy rates. Pregnancy rate following Ovsynch protocol was 40% (12/30) and 42.8% (6/14) in nulliparous and pluriparous buffaloes respectively (p = 0.8575). Most ovulations were synchronized and recorded at AI and the following day in nulliparous (24/30; 80%) and pluriparous (12/14; 85.7%) buffaloes respectively (p = 1.000). A follicle shift was recorded in 14 of 30 (46.6%) and 11 of 14 (78.5%) in nulliparous and pluriparous buffaloes respectively (p = 0.0466). Among established pregnancies: eight derived from follicle shift (66.6%) and four from no-follicle shift (33.3%) in nulliparous buffaloes, p = 0.0729 whereas in pluriparous buffaloes five (83.3%) derived from follicle shift and one from no-follicle shift (16.6%), p = 0.6154. Collectively, from 18 pregnancies in nulliparous and pluriparous buffaloes following Ovsynch protocol, 13 derived from follicle shift (72.2%) and five from no-follicle shift (27.7%), p = 0.0860. Pregnancy rate in pluriparous buffaloes following PRID-PMSG protocol was 70.5% (12/17). The majority of ovulations were synchronized and recorded at first, second AI and following day (13/17; 76.4%). A follicle shift occurred in 15/17 buffaloes (88.2%) and among the 12 recorded pregnancies, 11 derived from follicle shift (91.6%), p = 0.5147. In conclusion, pregnancy rates following Ovsynch protocol were similar in nulliparous and pluriparous cyclic buffaloes. A progestagen treatment on acyclic buffaloes but still displaying some ovarian follicular dynamics, resulted in significantly higher pregnancy rate compared with Ovsynch (p = 0.0376). According to the time of scheduled AI, a high degree of synchronized ovulations were recorded following the implementation of both protocols. 相似文献
370.