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Wikse SE McGrann JM Herd DB Falconer LL Holland PS Abello FJ Rogers GM Richardson DC Yoder DR Ramachandran S 《Journal of the American Veterinary Medical Association》2004,225(2):210-220
OBJECTIVE: To determine whether beef herds could increase profitability by reducing production cost per 100 lb (hundredweight [CWTI; ie, 45.4 kg) of calf through implementation of advice from teams of veterinarians and county extension agents supported by university specialists. DESIGN: Longitudinal study. SAMPLE POPULATION: 6 commercial cow-calf herds comprising 1,927 cows. PROCEDURE: Teams of veterinarians and county extension agents provided advice on 25 profitable ranch management practices to herd owners for 3 years. Use of each practice in herds was measured on a scale of 1 to 5 for baseline year 1999. Similar measurements were made at the end of each year for comparison with baseline values. Outcomes were measured by standardized performance analysis. RESULTS: Mean weaning weight of calves per exposed cow of the 6 herds increased significantly from 1999 (2000, 26.8 kg [59 lb; 17%]; 2001, 49.1 kg [108 lb; 31%]; and 2002, 43.2 kg [95 lb; 27%]). Mean cost per CWT of calf decreased significantly from the 1999 value (2000, -$20.04 [-18%]; 2001, -$33.40 [-29%]; and 2002, -$22.52 [-20%]). Additional profits for the 6 herds were $54,407 in 2000, $135,695 in 2001, and $116,089 in 2002 (3-year total of $306,191). Mean increase in management score of herds was positively correlated with increase in net income and accounted for > 60% of increased profits. CONCLUSIONS AND CLINICAL RELEVANCE: Profitability of beef cow-calf operations can be substantially increased through a team approach by identifying opportunities for improvements in management and helping ranch managers implement profitable practices. 相似文献
104.
Kapatkin AS Gregor TP Hearon K Richardson RW McKelvie PJ Fordyce HH Smith GK 《Journal of the American Veterinary Medical Association》2004,224(4):542-546
OBJECTIVE: To evaluate hip joint laxity in 10 breeds of dogs via 2 radiographic techniques. ANIMALS: 500 clinically normal dogs. DESIGN: Prospective study. PROCEDURE: Radiographs obtained via routine hip joint evaluations performed in sedated dogs of 10 popular breeds were randomly selected from a database. Measurements of distraction index (DI) and hip-extended index (HEI) on 1 hip joint radiograph randomly chosen from each dog were made. RESULTS: Mean age of dogs was 20.7 months. Mean HEI was 0.17 (range, 0.0 to 0.72) and mean DI was 0.44 (range, 0.07 to 0.96). Borzois had uniformly tight hip joints as judged by use of both methods and were considered the gold standard by which hip joint laxity was judged (all Borzois had DI < or = 0.32). Overall, DI was significantly greater than HEI. Within each breed, mean DI was always greater than mean HEI. Significant differences were detected among breeds for HEI; however, compared with DI, the magnitude of differences among breeds was less. CONCLUSIONS AND CLINICAL RELEVANCE: Distraction radiography detected the greatest range and magnitude of passive hip laxity in the 10 breeds of dogs. The difference in values between breeds known to have high prevalence of canine hip dysplasia and those in Borzois was greater for DI than for HEI. Breeds must be evaluated individually because of inherent differences in hip joint laxity. 相似文献
105.
The clinical, radiographic and echocardiographic features of two cases of pulmonic stenosis in cats are presented. A rarely reported combination of pulmonic stenosis and tricuspid valve dysplasia is described. 相似文献
106.
Serum and urinary markers of bone turnover may be of value in animals as noninvasive tools for determining the response of the skeleton to disease and injury. Although normal values for bone markers have been reported for the Beagle, concerns remain that breed to breed differences will complicate the interpretation of bone marker data in dogs. To explore this, we examined serum bone markers in two breeds of vastly different size, Pomeranians and Irish Wolfhounds. Our hypothesis was that serum concentrations of bone markers are similar in toy and giant dog breeds and fall within the same range as those reported for Beagles. Bone alkaline phosphatase (BALP) and carboxy-terminal telopeptide of type I collagen (ICTP), respectively markers of bone formation and bone resorption, were measured in age matched Pomeranians (n=14) and Irish Wolfhounds (n=14). No statistically significant differences between the mean BALP and mean ICTP serum concentrations from Pomeranians and Irish Wolfhounds were found. All BALP and ICTP concentrations were within the reference range reported for Beagles. The results of this study suggest that serum BALP and ICTP concentrations in giant and toy breeds are the same as in Beagles and that these assays may be used for dogs of all sizes. 相似文献
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Richardson F Osborne D 《The Canadian veterinary journal. La revue veterinaire canadienne》2006,47(3):277-8, 280, 282
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