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71.
Ketamine (0.3 mg/kg) administered intravenously to 12 halothane anesthetized horses caused a significant respiratory depression during ten minutes when respiration was spontaneous. Significant hemodynamic effects were not observed except for cardiac index. Clinical application was also discussed.  相似文献   
72.
73.
SUMMARY Eighty-five unsuckled newborn calves, were fed 1.5 L of colostrum of known IgG concentration at either 2, 4, 6 or 8 hours after birth with no additional colostrum feeding. Another group of 11 calves were left with their dam for 16 hours after birth, before separation. Blood samples were taken from all calves 24 hours after colostrum feeding or separation from the dam and serum Ig concentrations were measured by electrophoresis. There were no significant differences in mean serum Ig concentrations between calves fed at the different times after birth. Three of the 11 calves left to suckle were hypogamma-globulinaemic. Other calves in this group had higher serum Ig concentrations than the means of all other groups. All groups had mean serum Ig concentrations higher than the suggested minimum concentration required for adequate calf health. There were a number of calves that did not reach the suggested minimum serum concentration after feeding, but calf mortality was low and all calves were healthy apart from a slight scour for a few weeks after birth. There was no significant relationship between serum Ig concentration 24 to 48 hours after birth and either calf mortality or average growth rate over an 8- to 10-month period.  相似文献   
74.
2557 chicory roots from 13 cultivars were analysed individually for root weight, root shape, total fructose, total glucose, potassium and amino-N contents. Fructose yield is highly correlated with root weight and slightly with fructose content, both at the inter- and intra-varietal levels. The comparison of total-sample correlations to between- and within-variation correlations suggests an important genetic variation within varieties.  相似文献   
75.
Cerebellar abiotrophy in crossbred cattle   总被引:1,自引:0,他引:1  
Cerebellar abiotrophy affected 9 of 74 calves sired by a Poll Hereford bull over 2 successive calving seasons. The disease was characterised by episodes of recumbency and ataxia, with hypermetria and wide base stance. Clinical signs commenced between birth and 8 months of age. Two calves which were affected first at 8 months of age recovered clinically 9 months later. Histological lesions were found in the cerebellar cortex of 7 calves and consisted of segmental degeneration and loss of Purkinje cells, and axonal swellings. The clinical signs and pathological findings were consistent with bovine familial convulsions and ataxia, which has not been described previously in Australia. The clinical signs were not attributable to the lesions observed in the cerebellum and an underlying electrophysiological abnormality is proposed. The aetiology of the condition is probably genetic and appears to have a multifactorial basis.  相似文献   
76.
SUMMARY The prevalence of uterine disease was established during desexing of 175 bitches in the Torres Strait and Cape York, 42 of which had been treated with injectable medroxyprogesterone acetate (MPA) for oestrus postponement. The prevalence of uterine lesions was 45% for treated bitches, 5% for untreated bitches, and 14.9% for the sample population. A highly significant relationship (P<0.01) between MPA treatment and uterine lesions was established. A significant association (P<0.05) between age (>2 years old) and uterine lesions was found, most likely attributable to a significantly higher proportion (P<0.01) of MPA-treated bitches in the older population. There was no significant difference in the effect of MPA on the prevalence of uterine lesions between older and younger bitches. There was no effect of parity on the prevalence of uterine lesions.  相似文献   
77.
The objective of this study was to determine a value of serum progesterone (P4) concentration, assessed using an enzymeimmunoassay (EIA), for the early distinction between pregnant and non‐pregnant ewes and goats. Adult, non‐lactating ewes of Chios (n=53), Berrichon (n=30) and Sfakia (n=45) breeds were synchronized during the breeding season with progestagens and gonadotrophins and mated to fertile rams (Experiment I). Adult, lactating goats of Swiss breeds (Alpine and Saanen, n=104) and indigenous Greek breed (n=45) were synchronized during the transitional season with progestagens, PGF2α and gonadotrophins. Cervical artificial insemination (AI) with fresh semen was applied once, 42–44 h after sponge removal (Experiment II). Jugular blood samples were collected on day 19 after sponge removal (ewes) or on day 21 after AI (goats) and serum P4 concentration was determined by EIA. Progesterone concentrations ≥1.0, ≥1.5, ≥2.5 and ≥4.0 ng/ml were tested as indicative of pregnancy. Pregnancy diagnosis was verified on birth. In the case of sheep, using a discriminatory level of 2.5 ng/ml, overall accuracy of pregnancy diagnosis was 91.4% and predictive value of negative and positive diagnoses were 98.3 and 85.3%, respectively. In the case of goats, predictive value of negative diagnosis was 95.8 and 94.0% and predictive value of positive diagnosis 71.3 and 71.7%, for 1.5 and 2.5 ng/ml, respectively; overall accuracy was 79.2% using either level. The other discriminatory levels tested did not improve these results. A significant positive correlation was observed between P4 concentration and the number of lambs or kids born, and further analysis indicated that this relationship is not a simple linear function. Based on the results of this study, P4 concentrations of 2.5 ng/ml in the case of ewes and 1.5–2.5 ng/ml in the case of goats, determined with EIA, are proposed as discriminatory levels between pregnant and non‐pregnant animals, at an interval of one oestrous cycle after service.  相似文献   
78.
This study investigated whether Dalmatian puppies with normal hearing bilaterally had the same click-evoked brainstem auditory potential characteristics as age-matched dogs of another breed. Short-latency brainstem auditory potentials evoked by condensation and rarefaction clicks were recorded in 23 1.5- to 2-month-old Dalmatian puppies with normal hearing bilaterally by a qualitative brainstem auditory evoked potential test and in 16 Beagle dogs of the same age. For each stimulus intensity, from 90 dB normal hearing level down to the wave V threshold, the sum of the potentials evoked by the 2 kinds of stimuli were added, giving an equivalent to the alternate click polarity stimulation. The slope of the L segment of the wave V latency-intensity curve was steeper in Dalmatian (-40 +/- 10 micros/dB) than in Beagles (-28 +/- 5 micros/dB, P < .001) puppies. The hearing threshold was lower in the Beagle puppies (P < .05). These results suggest that interbreed differences may exist at the level of cochlear function in this age class. The wave V latency and wave V-wave I latencies differences at high stimulus intensity were different between the groups of puppies (4.3 +/- 0.2 and 2.5 +/- 0.2 milliseconds, respectively, for Beagles; and 4.1 +/- 0.2 and 2.3 +/- 0.2 milliseconds for Dalmatians, P < .05). A different maturation speed of the neural pathways is one possible explanation of this observation.  相似文献   
79.
A new monoclonal antibody (mAb), CCV2-2, was compared with the widely used FIPV3-70 mAb, both directed against canine coronavirus (CCoV), as a diagnostic and research tool. Western blot showed that both anti-CCoV mAbs only reacted with a protein of 50 kD, a weight consistent with the feline coronavirus (FCoV) viral nucleocapsid. A competitive inhibition enzyme-linked immunosorbent assay showed that the 2 recognized epitopes are distinct. Preincubation of CCV2-2 mAb with FCoV antigen suppressed the immunostaining. Formalin-fixed, paraffin-embedded sections from brains of 15 cats with the dry form of feline infectious peritonitis (FIP) were examined by immunohistochemistry. Immunohistochemistry was performed with both anti-CCoV mAbs, either on consecutive or on the same sections. A myeloid-histiocytic marker, MAC 387, was also used to identify FIP virus-infected cells. In all regions where MAC 387-positive cells were present, positive staining with the CCV2-2 mAb was systematically detected, except at some levels in 1 cat. In contrast, none or only a few cells were positive for the FIPV3-70 mAb. Double immunostaining showed macrophages that were immunopositive for either CCV2-2 alone or alternatively for CCV2-2 and FIPV3-70 mAbs. This reveals the coexistence of 2 cohorts of phagocytes whose FIP viral contents differed by the presence or absence of the FIPV3-70-recognized epitope. These findings provide evidence for antigenic heterogeneity in coronavirus nucleocapsid protein in FIP lesions, a result that is in line with molecular observations. In addition, we provide for the first time morphologic depiction of viral variants distribution in these lesions.  相似文献   
80.
OBJECTIVE-To evaluate a laparoscopic technique for implantation of a urinary catheter in the right paramedian area in male sheep and to determine feasibility, benefits, and risks for this technique. DESIGN-Evaluation study. ANIMALS-6 Healthy male sheep (mean +/- SD body weight, 42.16 +/- 11.95 kg [92.75 +/- 26.29 lb]). PROCEDURES-Each sheep was anesthetized and positioned in dorsal recumbency. A 10-mm laparoscope was inserted in the right paramedian area between the xiphoid and preputial orifice. After creation of capnoperitoneum, grasping forceps were inserted in the left paramedian area at the level of the teats and used to immobilize the urinary bladder. A pigtail balloon catheter was implanted transcutaneously in the right paramedian area between the preputial orifice and teats and directed into the urinary bladder by use of laparoscopic guidance. The catheter was removed 10 days after implantation. Fourteen days after initial surgery, a second laparoscopy was performed to evaluate pathologic changes. RESULTS-Inadvertent insertion of the first trocar into the rumen of 1 sheep was the only intraoperative complication encountered. Laparoscopic-assisted implantation of the urinary catheter was successfully performed in all sheep. No postoperative complications were detected. CONCLUSIONS AND CLINICAL RELEVANCE-Laparoscopic-assisted implantation of a urinary catheter in the right paramedian area was successfully performed and may be a feasible method for use in sheep. This method can be considered as an alternative to tube cystotomy performed by laparotomy.  相似文献   
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