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81.
The present study was conducted to evaluate two Indian native chicken breeds, namely, Aseel and Kadaknath for fertility, hatchability, genetic parameters of juvenile growth traits, and semen quality traits at the onset of sexual maturity. The fertility was similar in Aseel (86.96%) and Kadaknath (85.15%); however, a relatively higher hatchability was observed in Kadaknath (77.94%) than Aseel (70.74%). Heritability estimates of body weights at 4 weeks of age were almost similar in Aseel (0.37) and Kadaknath (0.39), while the estimate of body weight at 6 weeks of age was higher in Aseel (0.42) than Kadaknath (0.31). The heritability estimate of shank length at 6 weeks of age was lower in Aseel (0.16) compared to Kadaknath (0.35). The age at first egg in the flock was comparable in Aseel (148 days) and Kadaknath (150 days). Aseel breed with significantly (P ≤ 0.001) higher body weight, absolute and relative testes weights had significantly higher semen volume (P ≤ 0.05) and sperm motility (P ≤ 0.01) but had lower seminal plasma cholesterol level (P ≤ 0.05) as compared to Kadaknath. It can be concluded that there is a scope for genetic improvement of these two native breeds for juvenile growth traits since heritability estimates of these traits were relatively high.  相似文献   
82.
Despite the importance of small ruminants breeding in developing countries, milk/meat productivity remains unsatisfactory. Infectious diseases, such as leptospirosis, brucellosis, and small ruminant lentiviruses (SRLVs), contribute to this scenario. The objective of the present study was to determine the role of each of these diseases in the productivity of small ruminants breeding in Rio de Janeiro, Brazil. In goats, 343 samples were tested for leptospirosis, 560 for Brucella abortus, and 506 for caprine arthritis-encephalitis (CAE), whereas in sheep, 308 samples were tested for leptospirosis, 319 for B. abortus, 374 for Brucella ovis, and 278 for Maedi-Visna (MV). Regarding leptospirosis, 25.9% of goats and 47.4% sheep were seroreactive, with serovar Hardjo the most prevalent in both species. Anti-B. abortus agglutinins were found in 0.7% of all samples, exclusively in goats. In relation to SRLVs, 8.6% of goats and 3.2% of sheep samples were positive for CAE and MV, respectively. Leptospirosis was the major infectious problem in the small ruminants sampled and may contribute to impaired productivity of these animals.  相似文献   
83.
84.
PRACTICAL RELEVANCE: Calcium oxalate (CaOx) containing stones are among the most common of the urinary tract stones identified in cats. RISK FACTORS: Risk factors for CaOx stone formation include such things as breed, gender and diet; stress and obesity have also been hypothesized to be risk factors for this disease. MANAGEMENT APPROACH: A tailored, individual management strategy for preventing CaOx stone recurrence is important and should include addressing the diet, environment and any other comorbid conditions present. Increasing the cat's moisture intake is one of the key mechanisms for preventing recurrence. CLINICAL CHALLENGES: CaOx ureterolithiasis has emerged as a difficult and sometimes life-threatening problem for cats. In those cats where stones are found incidentally, periodic monitoring may be required to assess for disease progression. Interventional procedures such as ureteral stent placements are now increasingly being performed for recurrent cases or those with larger stone burdens. Periodic radiographs for more severe cases and frequent client communication can help ensure successful outcomes for cats with lower and upper CaOx stone disease. EVIDENCE BASE: Limited evidence-based studies are published regarding management of feline upper and lower urinary tract CaOx stone disease, making this a difficult condition to manage in some cats. Studies designed to evaluate the relationship to dietary modifications, medical management, stress, obesity and surgical techniques are warranted in cats with upper and lower urinary tract CaOx stones.  相似文献   
85.
OBJECTIVE: To determine the effect of oral administration of dantrolene sodium on serum creatine kinase (CK) activity after exercise in horses with recurrent exertional rhabdomyolysis (RER). ANIMALS: 2 healthy horses and 5 Thoroughbreds with RER. PROCEDURE: 3 horses received 2 doses of dantrolene (4, 6, or 8 mg/kg, p.o., with and without withdrawal of food) 2 days apart; 90 minutes after dosing, plasma dantrolene concentration was measured spectrofluorometrically. On the basis of these results, 5 Thoroughbreds with RER from which food was withheld received dantrolene (4 mg/kg) or an inert treatment (water [20 mL]) orally 90 minutes before treadmill exercise (30 minutes, 5 d/wk) during two 3-week periods. Serum CK activity was determined 4 hours after exercise. Plasma dantrolene concentration was measured before and 90 minutes after dosing on the first and last days of dantrolene treatment and before dosing on the first day of the inert treatment period, RESULTS: 90 minutes after dosing, mean +/- SEM plasma dantrolene concentration was 0.62 +/- 0.13 and 0 microg/mL in the dantrolene and inert treatment groups, respectively. Serum CK activity was lower in dantrolene-treated horses (264 +/- 13 U/L), compared with activity in water-treated horses (1,088 +/- 264 U/L). Two horses displayed marked muscle stiffness on the inert treatment. CONCLUSIONS AND CLINICAL RELEVANCE: In 5 horses with RER from which food had been withheld, 4 mg of dantrolene/kg administered orally provided measurable, though variable, plasma concentrations and significantly decreased serum CK activity after exercise in 4 of those horses.  相似文献   
86.
A modified AACC 45‐g flour cookie procedure using asymmetrical centrifuge mixing as a replacement for conventional mixing has been developed. Ingredients are added to a pin cup in the same proportion as in the Approved Method 10‐50D (AACC 2000) sugar‐snap cookie test and mixed in a single step for 15 sec at 2,500 rpm. The dough is then processed and the resulting cookies are scored according to the AACC Approved Method 10–52 40‐g flour micro cookie test method. Cookies produced from a control cookie flour and four commercial soft wheat flours with the new mixing method did not show the characteristic surface cracking patterns normally obtained with conventional three‐stage mixing. However, with the exception of one spread value, no significant differences in spread, thickness, or the ratio of spread to thickness were evident when results were compared with those obtained with the AACC Approved Method 10‐50D 225‐g flour test method using a Hobart mixer equipped with a paddle. Cookies produced from two sets of advanced soft white spring wheat breeder lines, including control cultivars, using the asymmetrical centrifuge mixing procedure were also very comparable in spread, thickness, and ratio compared with those produced using 225 g of flour in the AACC Approved Method. Reproducibility of test results for all cookie parameters for both commercial and advanced plant breeder samples were comparable to the AACC Approved Method 10‐50D 225‐g flour test method. The very short mixing time and the ability to quickly clean or use multiple pin cups should allow very high throughput of flour samples relative to the use of conventional mixers for cookie testing.  相似文献   
87.
88.
The objective of this study was to evaluate and compare physical parameters in groups of sheep with different phenotypic characteristics in the Centre-west region of Brazil. Five groups of sheep, with nine animals per group, were selected, three groups of Santa Inês animals with different coat colours (white, brown and black), one group with crossbred animals (Santa Inês × Bergamasca) and one group with animals of the Bergamasca breed. The following traits were evaluated: coat thickness, number and length of hair, pigmentation level in the coat and the skin as well as the percentage area of sweats glands in the skin tissue, carried out by histological analysis. The number of hairs and the area of sweats glands were not significantly different between the evaluated groups. The Bergamasca breed showed low pigmentation of the skin and long hairs. The levels of pigmentation of the hair and of the skin were highly correlated. Between the Santa Inês groups, the group with white hair showed the better parameters for heat adaptation, while the brown hair group showed the lower heat adaptation when compared with another hair breed groups.  相似文献   
89.
The aim of this study was to determine the fattening performance and the slaughter and carcass characteristics of Akkeçi (Saanen × Kilis (B1) crossbred) male kids raised in individual crates (IC) or in group pen housing (GP). In both GP and IC groups, total 13 heads of male kids, whose initial body weights were 21.43 ± 1.03 kg and 20.61 ± 0.98 kg, respectively, evaluated for their fattening performances. After 56 days of the fattening period, the final body weights and average daily weight gains of the GP and IC kids were recorded as 30.84 ± 0.82 kg and 25.84 ± 0.76 kg; 182.42 ± 14.77 g and 92.09 ± 13.76 g, respectively (P < 0.001). Adrenal gland weights of the GP and IC groups were similar as 1.66 ± 0.25 g and 1.77 ± 0.22 g, respectively. Although, the carcass conformation of kids was similar between groups, there were significant differences between GP and IC groups for some slaughter and carcass characteristics. In general, although housing kids reared in individual crates provides opportunity to individually feed and monitor a kid, the results obtained from the individual crates in the present study were not satisfactorily from the ethological and production points of view.  相似文献   
90.
The objective of this study was to determine the effect of some factors on the length of productive life (LPL), the number of parities (NP), and the culling interval (CI) of sows. The information from 2003 to 2009 of 3,746 sows with LPL and NP records and 5,819 sows with CI records from the four farms of Yucatan, Mexico was used. LPL was defined as the number of days between the first farrowing and culling or death and CI as the number of days between the last farrowing and culling. To determine the effects of farm, litter size at first farrowing (LSF1) and age at first farrowing (AF1) on LPL and NP, and of farm, LSF1 and culling reason on CI general linear models were used. Means and standard errors for LPL, NP, and CI were 496.4 ± 8.42 days, 3.35 ± 0.04 parities, and 48.3 ± 0.52 days, respectively. All factors had significant effects (P < 0.05) on LPL, NP, and CI. The sows from farm 2 stayed longer (806.0 days) and had more parities (5.25) than the sows from the other farms. Sows with the smallest litters (≤8 piglets) at first farrowing stayed the least time in the farm (675.1 days) and had the fewest parities (4.49). Gilts farrowing the first time before 331 days of age stayed longer time in the farm (726.4 days) and had more parities (4.81) in comparison with 331–348 and more than 348 days age groups. With respect to CI, the sows in farm 3 stayed the longest time in the farm. Sows with more than five parities were culled sooner after their last farrowing. In conclusion, differences between farms for LPL, PN, and CI were found. Females that farrowed at a short age and those with large litters stayed longer in the herd. Old sows and those culled for reproductive reasons stayed the least time in the herd after their last farrowing.  相似文献   
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