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991.
Three studies were conducted to evaluate the feasibility of field peas as a protein source in diets for beef cattle. In the first study, 4 cultivars of field pea were incubated in situ to determine rate and extent of CP disappearance. Results indicate that field pea cultivars vary in CP content (22.6, 26.1, 22.6, and 19.4%, DM basis for Profi, Arvika, Carneval, and Trapper, respectively). Soluble protein fraction ranged from 34.9% for Trapper to 54.9% for Profi. Degradable CP fraction was greater (P = 0.01) for Trapper compared with the other cultivars, and no differences (P ≥ 0.25) were observed among Profi, Arvika, and Carneval. Rate of CP degradation differed (P ≤ 0.03) for all cultivars, with Profi being the greatest and Trapper the smallest (10.8, 10.0, 8.1, and 6.3 ± 1.4%/h for Profi, Carneval, Arvika, and Trapper, respectively). Estimated RDP was not different (P = 0.21) for all 4 cultivars. In the second study, 30 crossbred beef steers (301 ± 15 kg) were individually fed and used to evaluate effects of field pea processing (whole, rolled, or ground) on steer performance. Diets contained 40% field pea grain. Growing steers consuming whole field pea had greater ADG (P = 0.08) than those consuming processed field pea (1.69, 1.52, and 1.63 ± 0.05 kg/d, for whole, rolled, and ground, respectively). However, DMI (kg/d and as % of BW) and G:F were not different (P ≥ 0.24). In the third study, 35 individually fed gestating beef cows (694 ± 17 kg) were used to evaluate the use of field pea as a protein supplement for medium quality grass hay (9.3% CP). Treatments consisted of whole field peas at 1) 0 g (CON), 2) 680 g (FP680), 3) 1,360 g (FP1360), and 4) 2,040 g (FP2040), and 5) 1,360 g of 74% barley and 26% canola meal (BCM). Total intake (forage + supplement) of gestating beef cows increased with increasing field pea level (linear, P = 0.01; supplemented vs. nonsupplemented, P = 0.01). In summary, protein quantity and rate of ruminal protein degradation vary across sources of field peas used in this study. Additionally, because of source variability, nutrient analysis and animal requirements should be considered when field pea is incorporated into beef cattle diets. Processing field pea does not improve performance of growing steers. Supplementation of field pea to gestating cows consuming medium-quality grass hay increased total DMI. Overall, our data indicate field pea can be used in a wide variety of beef cattle diets.  相似文献   
992.
The Nc-Spain 7 isolate of Neospora caninum, which was newly obtained from an asymptomatic congenitally infected calf, demonstrated a similar virulence as Nc-1 strain in mouse models. The aim of this study was to characterize the pathogenesis of Nc-Spain 7 isolate in cattle after experimental infection at 65 days of gestation. For this purpose, thirteen pregnant heifers were divided into three groups as follows: group A: 7 heifers inoculated with 1×10(8) tachyzoites of Nc-Spain 7 isolate; group B: 4 heifers inoculated with 1×10(8) tachyzoites of Nc 1 strain; and group C: 2 heifers received PBS. Serum samples were collected weekly and heparinized blood samples were collected three times (0, 28 and 42 days after inoculation) by jugular venipuncture. Placenta and fetal tissue samples were collected at time of necropsy. Specific antibody response in the dams was tested by IFAT, indirect ELISA, and rNcGRA7 and rNcSAG4 based-ELISA. Specific antibody response in fetal fluids was tested by IFAT. IFN-γ production was measured after in vitro culture of PBMC and the supernatant was assessed using a commercial kit (BOVIGAM). A significant increase in N. caninum antibody responses was detected in groups A and B by IFAT and by i-ELISA from day 14 after inoculation onwards. Besides, antibody response against rNCGra7 protein was also detected in all inoculated heifers by rNcGra7-based ELISA. Four fetuses from group A and one from group B were aborted between 3 and 5 weeks after infection. In the recovered fetuses, only 3 out of 4 fetal fluids from fetuses of group A and 1 out of 3 of group B were seropositive by IFAT, but all of them were positive by PCR. Transplacental transmission could be determined in all fetuses from groups A and B by PCR and/or IHC. Heifers of group C and their fetuses remained negative by all techniques. The results of this study demonstrate that the NC-Spain 7 isolate could be transmitted transplacentally, and produced fetal death and abortion in cattle.  相似文献   
993.
994.
A survey to document tick control methods used by resource-limited farmers in the control of cattle ticks in the Eastern Cape Province of South Africa was conducted by interviewing 59 cattle farmers using structured questionnaires and general conversation. Information collected was on external parasites of cattle, their effects and their control methods. Ticks were reported to be a major problem causing diseases like anaplasmosis (89.8%), babesiosis (55.9%) and ehrlichiosis (16.9%), as well as wounds that predispose to screwworm infestation, tick worry and teat damage to cows troubling farmers in their farming enterprises. The main tick control methods were; acaricides provided by government, however 94.9% of the farmers interviewed were of the opinion that the dip wash is not effective in killing the ticks. As a result, farmers complement the government dipping service with their own initiatives like spraying with conventional acaricides (22%), household disinfectants such as Jeyes fluid (18.6%), used engine oil (10.2%), chickens (5.1%), manual removal (5.1%), and pouricides (1.7%). In addition, some farmers also use plants (6.8%), mainly the leaf of Aloe ferox and the bark of Ptaeroxylon obliquum. The study revealed ticks to be a major problem in the study area.  相似文献   
995.
The handled trot of three Lusitano Purebred stallions was analyzed by using 2D and 3D kinematical analysis methods. Using the same capture and analysis system, 2D and 3D data of some linear (stride length, maximal height of the hoof trajectories) and angular (angular range of motion, inclination of bone segments) variables were obtained. A paired Student T-test was performed in order to detect statistically significant differences between data resulting from the two methodologies With respect to the angular variables, there were significant differences in scapula inclination, shoulder angle, cannon inclination and protraction-retraction angle in the forelimb variables, but none of them were statistically different in the hind limb. Differences between the two methods were found in most of the linear variables analyzed.  相似文献   
996.
The hemolytic activity of 22 Trichomonas gallinae isolates was investigated using an 18 h erythrocyte hemolysis assay which has been shown to correlate with the clinical virulence of T. vaginalis. Absorbance of the assay supernatants was measured at 540 nm and expressed as percentage of complete hemolysis. Mean hemolytic activity of the T. gallinae isolates ranged from 3.5% to 53.4% and did not correspond with clinical virulence. The results of this investigation suggest hemolytic activity is not a useful in vitro virulence assay for T. gallinae.  相似文献   
997.
Objective— To report arthroscopic diagnosis and treatment of synovial hemangioma in a dog.
Study Design— Case report.
Animal— Standard Poodle (8-year-old neutered male).
Methods— A soft tissue density mass observed radiographically in the left stifle joint of a dog with a 2-month history of recurrent lameness, hemarthrosis, and a slight cranial drawer sign, was located by diagnostic arthroscopy and surgically excised via arthrotomy.
Results— Histologic evaluation revealed tissue composed of variably sized cavernous vascular spaces filled with erythrocytes that were considered compatible with synovial hemangioma.
Conclusions— In this dog, synovial hemangioma evident as a soft tissue mass on radiographs was associated with chronic lameness and hemarthrosis, and resolved with surgical excision.
Clinical Relevance— Synovial hemangioma, although seemingly rare in dogs, should be considered in the differential diagnosis for nontraumatic, recurrent lameness, and unresponsive to anti-inflammatory therapy when there is a circumscribed intracapsular soft tissue mass evident radiographically together with hemarthrosis.  相似文献   
998.
Objective— To describe the signalment, history, clinical signs, surgical technique, and outcome for cats with laryngeal paralysis that had arytenoid lateralization.
Study Design— Case series.
Animals— Cats with laryngeal paralysis (n=10).
Methods— Medical records (1996–2002) for cats with laryngeal paralysis that had arytenoid lateralization were reviewed for signalment, history, clinical signs, degree of paralysis, cause, concurrent medical conditions, surgical technique, and outcome. Follow-up information was obtained from owners or referring veterinarians.
Results— Of 10 cats, 9 had bilateral and 1 had unilateral laryngeal paralysis. Arytenoid lateralization were unilateral (n=7), bilateral (1), and staged bilateral procedures (2), 10 days and 3 years apart, respectively. Postoperatively, 1 cat had persistent inspiratory noise because of minimal enlargement of the rima glottidis and 2 cats required a temporary tracheostomy for management of laryngeal swelling. Three cats developed aspiration pneumonia and died 4, 7, and 150 days after surgery; all 3 had bilateral (simultaneous or staged) procedures. Of the 7 remaining cats, 4 were alive at follow-up and 3 had died of causes unrelated to arytenoid lateralization. The calculated mean survival time for all 10 cats was 406 days (median, 150 days; range, 4–1825 days).
Conclusions— Arytenoid lateralization was effective at enlarging the rima glottidis and reducing signs of airway obstruction in most cats.
Clinical Relevance— Unilateral arytenoid lateralization is a feasible option for the surgical management of cats with marked clinical signs; however, bilateral procedures should be avoided or at least performed with considerable caution because of the apparent risk for aspiration pneumonia.  相似文献   
999.
Thirty dogs with atopic dermatitis were given tepoxalin (Zubrin®, Intervet/Schering-Plough Animal Health, Boxmeer, the Netherlands) or placebo once daily for 4 weeks, followed by a wash-out period of 1 week before reversing the treatments. Pruritus was scored by the owners using the Edinburgh Pruritus Scale and one investigator employed a modification of the Canine Atopic Dermatitis Extent and Severity Index-01 (mCADESI-01) to score the physical lesions. After administration of tepoxalin there was a ≥ 50% reduction in pruritus and mCADESI-01 scores in 36% and 25% of the dogs, respectively, whereas following administration of the placebo there was a ≥ 50% reduction in pruritus and mCADESI-01 scores in only 25% and 16% of the dogs, respectively. Analysis of pooled data indicated that tepoxalin resulted in a significant reduction in pruritus ( P  = 0.012) and mCADESI-01 ( P  = 0.002) scores but there was no significant change after placebo. The median pruritus scores before and after tepoxalin were 2 (range 1–5) and 1 (range 0–5), respectively, and before and after placebo were 2 (range 0–4) and 2 (range 0–4), respectively. The median mCADESI scores before and after tepoxalin were 23 (range 0–68) and 16 (range 0–72), respectively, and before and after placebo were 18 (range 3–79) and 24 (range 0–65), respectively. At the dose used in this study (10.0–19.1 mg kg−1), tepoxalin was well-tolerated and no adverse effects were noted.  相似文献   
1000.
Acrosin is an acrosomal protease synthesized as an inactive precursor, proacrosin, which is processed via autoproteolysis into active forms alpha- and beta-acrosin. In this paper, a comparative study on the immunoreactivity of acrosin during in vitro capacitation of frozen and fresh (control) canine sperm using Western blot analysis is reported. Semen samples were obtained by digital stimulation and ejaculates processed as fresh and frozen samples and then capacitated for 0, 30, 60 and 90 min. At each time period, samples were analyzed with monoclonal antibody C5F10 by Western blot. The antibody specifically recognized, in fresh and frozen/thawed spermatozoa, a 40-, 32- and 27-kDa bands corresponding to proacrosin, alpha- and beta-acrosin, respectively, during capacitation. Western immunoblots showed that the beta-acrosin reactivity in fresh sperm was directly proportional to the time of capacitation, whereas a decreased reactivity of active form of acrosin was observed with frozen-thawed sperm (p   < 0.05). These results suggest that proacrosin is activated to beta-acrosin earlier in frozen/thawed dog spermatozoa than in fresh dog spermatozoa.  相似文献   
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