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61.
Linear, temporal and angular biokinematic characteristics of the forelimb at the walk in different breeds were determined, highlighting inter-breed differences. Twenty-three healthy stallions were used: ten Andalusians (AN), seven Arabs (AR) and six Anglo-Arabs (AA). Height at the withers was significantly different between groups (P < 0.001). Six trials per horse were recorded using a levelled video camera (sampling frame rate 25 frames/s), digitized and analysed using a semi-automatic movement analysis system. No statistically significant differences in speeds were recorded between breeds (P > 0.05). The only temporal parameter which was similar in the three breeds was the moment at which the hoof reached the highest point in its trajectory. The variables presenting the most significant differences were the percentages of deceleration and propulsion within the stance phase. ANOVA for angular variables showed that the greatest difference was in the range of angular movement of the carpal joint, being higher in AN, due to a lower minimum value. In the fetlock joint, the greatest difference was observed in minimum values, which differed in all three breeds. Significant inter-breed differences were also observed for maximum limb retraction, being lowest in the AN group, followed by the AA and AR groups. This finding was reflected in the angular range of motion, despite smaller differences in the degree of limb protraction; very similar values were reported in all three breeds. As regards the elbow joint, no inter-breed differences were observed in terms of minimum values, whereas differences were recorded for maximum and angular range of motion, higher values being displayed by the AR and AN groups than by AA animals. In conclusion, inter-breed differences may be determined in equine forelimb biokinematics at the walk. This study distinguished between AN, AR and AA horses.  相似文献   
62.
N,N-Diethyl-, N,N-dipropyl-, N,N-di-isopropyl, and N,N-di-isobutylalkanamides in which the acyl moiety ranged from C8 to C21 were synthesised, and their larvicidal activity was determined against the first-instar larvae of the southern house mosquito Culex quinquefasciatus Say. The four homologous series of amides generally showed an increase in their larvicidal activity as the carbon number in the acyl moiety of the amides increased, until the activity reached a maximum. Subsequently, an increment of carbon number resulted in declining activity in the higher homologues, until the activity disappeared. N,N-Diethyltetradecanamide, N,N-dipropylundecanamide, N,N-di-isopropylundecanamide, and N,N-di-isobutlynonanamide or -dodecanamide were the most active compounds in their respective homologous series of amides; however, they were less active than their analogous N,N-dimethylalkanamides previously studied.  相似文献   
63.
The effect of breed and diet on insulin response to glucose challenge and its relation to intramuscular fat deposition was determined in 36 steers with 12 each of greater than 87% Wagyu (referred to as Wagyu), Wagyu x Limousin, and Limousin breeds. Weaned steers were blocked by weight into heavy, medium, and light calves and placed in six pens with two pens per weight type and with two steers of each breed per pen. Three pens with steers from each weightclass were fed backgrounding and finishing diets for 259 d, while the other three pens were fed the same diets where 6% of the barley grain was replaced with sunflower oil. Prior to initiation of the finishing phase of the study the intravenous glucose tolerance test (VGTIT) was conducted in all steers. Once steers were judged as carrying adequate 12th-rib fat, based on weight and days on feed, they were harvested and graded and samples of the longissimus muscle were procured for determination of fat content and fatty acid composition. Dietary oil improved (P = 0.011; 0.06) ADG and feed conversion efficiency of steers during the latter part of backgrounding and only ADG during early part ofthe finishing period. Generally percent kidney, pelvic, and heart fat was the only adiposity assessment increased (P = 0.003) by dietary oil. The IVGTT results indicated that insulin response to intravenous glucose was lower in Limousin steers than in Wagyu steers. Dietary oil decreased (P = 0.052) fasting plasma insulin concentration in Wagyu steers compared with Limousin steers. The correlation coefficients among the IVGTT measures and intramuscular fat content or marbling score were less than 0.4, and only a negative trend existed between fasting insulin and USDA marbling scores. However, the carcasses of the Wagyu steers graded US Choice, and 66% of the Wagyu carcasses graded US Prime, which were substantially better than the quality grades obtained for the carcasses from the other breed types. Dietary oil did not affect muscle fat content but increased (P = 0.01) conjugated linoleic acid (CLA) concentrations by 339%. Results indicated that IVGTT measures were not appropriate indices of marbling potential in cattle and that dietary oil can enhance CLA content of beef.  相似文献   
64.
The aim of this study was to determine the influence of a 10-month training programme on the linear, temporal and angular characteristics of the fore and hind limbs at the trot in the Andalusian horse, using standard computer-aided videography. Sixteen male Andalusian horses were observed before and after training. Six strides were randomly selected for analysis in each horse and linear, temporal and angular parameters were calculated for fore and hind limbs. The training programme used here produced significant changes in kinematic parameters, such as shortening of stride length, and increase in swing duration and a decrease in hind limb stance percentage. No significant differences were recorded in the angular values for the forelimb joints. In trained horses, the more proximal joints of the hind limb, especially the hip and stifle, had a greater flexion while the fetlock showed a smaller extension angle. At the beginning of the swing phase, hip and stifle joints presented angles that were significantly more flexed. When the hind limbs came into contact with the ground, all the joints presented greater flexion after training.  相似文献   
65.
E-octadec-7-en-5-ynoic acid from the roots of Capparis zeylanica   总被引:1,自引:0,他引:1  
A new fatty acid, E-octadec-7-en-5-ynoic acid (1), has been isolated from chloroform extract of the roots of Capparis zeylanica. The structure of this compound was established primarily by 1D and 2D-NMR spectroscopy.  相似文献   
66.
67.
The value of sunflower seed (SS) in finishing diets was assessed in two feeding trials. In Exp. 1, 60 yearling steers (479 +/- 45 kg) were fed five diets (n = 12). A basal diet (DM basis) of 84.5% steam-rolled barley, 9% barley silage, and 6.5% supplement was fed as is (control), with all the silage replaced (DM basis) with rolled SS, or with grain:silage mix replaced with 9% whole SS, 14% whole SS, or 14% rolled SS. Liver, diaphragm, and brisket samples were obtained from each carcass. In Exp. 2, 120 yearling steers (354 +/- 25 kg) were fed corn- or barley-based diets containing no SS, high-linoleic acid SS, or high-oleic acid SS (a 2 x 3 factorial arrangement, n = 20). Whole SS was included at 10.8% in the corn-based and 14% in the barley-based diets (DM basis). In Exp. 1, feeding whole SS linearly increased DMI (P = 0.02), ADG (P = 0.01), and G:F (P = 0.01). Regression of ME against level of whole SS indicated that SS contained 4.4 to 5.9 Mcal ME/kg. Substituting whole for rolled SS did not significantly alter DMI, ADG, or G:F (8.55 vs. 8.30 kg/d; 1.36 vs. 1.31 kg; and 0.157 vs. 0.158, respectively). Replacing the silage with rolled SS had no effect on DMI (P = 0.91) but marginally enhanced ADG (P = 0.10) and improved G:F (P = 0.01). Dressing percent increased linearly (P = 0.08) with level of SS in the diet. Feeding SS decreased (P < 0.05) levels of 16:0 and 18:3 in both diaphragm and subcutaneous fats, and increased (P = 0.05) the prevalence of 18:1, 18:2, cis-9,trans-11-CLA and trans-10,cis-12-CLA in subcutaneous fat. In Exp. 2, barley diets supplemented with high-linoleic SS decreased DMI (P = 0.02) and ADG (P = 0.007) by steers throughout the trial, whereas no decrease was noted with corn (interaction P = 0.06 for DMI and P = 0.01 for ADG). With barley, high-linoleic SS decreased final live weight (554 vs. 592 kg; P = 0.01), carcass weight (329 vs. 346 kg; P = 0.06), and dressing percent (58.5 vs. 59.4%; P = 0.04). Steers fed high-linoleic SS plus barley had less (P < 0.05) backfat than those fed other SS diets. No adverse effects of SS on liver abscess incidence or meat quality were detected. Although they provide protein and fiber useful in formulating finishing diets for cattle, and did improve performance in Exp. 1, no benefit from substituting SS for grain and roughage was detected in Exp. 2. Because of unexplained inconsistencies between the two experiments, additional research is warranted to confirm the feeding value of SS in diets for feedlot cattle.  相似文献   
68.
Seroprevalence of Toxoplasma gondii was tested for in 585 cats in different regions of Spain. Sera were tested by the indirect immunofluorescence antibody test (IFAT). Specific antitoxoplasma IgG (IFAT titer>or=1/80) were found in 189 of 585 (32.3%): 117 of 317 (36.9%) stray cats, 16 of 48 (33.3%) farm cats and 56 of 220 (25.5%) household cats. The overall prevalence was significantly higher in stray groups (36.4% of 365) than in household cats (25.5% of 220), higher in adult cats (>6 months old, 36.8% of 443) than in juvenile cats (<6 months old, 13.9% of 101), and higher in male stray cats (45.3% of 128) than in female stray cats (32% of 153). Prevalence of intestinal parasites was also analysed by a routine coprological method in 382 of the 585 cats. Intestinal parasites were found in 107 faecal samples (28%): 76 of 231 (32.9%) stray cats, 14 of 48 (29.2%) farm cats and 17 of 103 (16.5%) household cats. T. gondii oocysts were not found in any faecal samples analysed. The following prevalences of other intestinal parasites were found: Toxocara cati (18.3%), Toxascaris leonina (1.3%), Ancylostoma sp. (1%), Capillaria spp. (1.3%), Aelurostrongylus abstrusus (1%), Taenia like (3.7%), Dipylidium caninum (2.6%) and Cystoisospora spp. (6.3%).  相似文献   
69.
The objective was to evaluate chemical, mechanical, and sensory attributes associated with tenderness in divergent cattle breeds--Wagyu (W; n = 12), Limousin (L; n = 12) and F1-cross (WxL; n = 12)--fed two dietary treatments (0 or 6% sunflower oil (DM basis)). A randomized complete block repeated measures design in a 3 x 2 factorial arrangement of treatments was used, and effects of breed, diet, block, and associated interactions were tested. Cattle were fed barley-based diets for an average of 259 d. Twenty-four hours postmortem (PM), steaks from the longissimus muscle (LM) were sliced, vacuum-packaged, aged (1, 3, 7, 14, 28, and 56 d PM) at 2 degrees C, and frozen (-40 degrees C) until analyzed. Wagyu steaks had lower (P < 0.05) Warner-Bratzler shear force (WBSF) values than L steaks across all aging times. At 1 d PM, W steaks required slightly more (P > 0.05) force to shear than WxL or L (0.30 and 0.11 kg, respectively); however, by d 14 PM, W steaks required 0.77 kg less (P < 0.05) force to shear than L. Wagyu steaks received higher (P < 0.05) sensory panel sustained tenderness scores at d 14 PM than L. The pH decline was slower (P < 0.05), and temperature decline more (P < 0.05) rapid, in W carcasses than L or WxL carcasses. Breed and diet did not affect (P > 0.10) free calcium levels (FCL) over time (0, 1, 3, 7, and 14 d PM), 0-h calpastatin activity (CA), d-1 percent collagen (OH-PRO), or d-1 collagen cross-linking (HP). Western blot analysis for the presence of the troponin-T (TNT) 30-kDa fragment, conducted only on samples from steers fed the 0% sunflower oil diet, demonstrated more proteolysis by d 3 PM in L than W or WxL. Overall, breed differences in mechanical and sensory measures of tenderness were not explained by FCL, CA, OH-Pro, and HP. Even though the initial appearance of the TNT 30-kDa fragment was greater in L, linear slopes for appearance of TNT degradation product across aging time were greater for W and WxL (P < 0.01 and P = 0.056, respectively) than for L, suggesting that tenderness differences due to breed may have been facilitated by more-rapid proteolytic degradation over time.  相似文献   
70.
In this study, Neospora caninum seroprevalence and some associated risk factors were investigated in four different dog populations in Spain. N. caninum seropositivity was significantly higher in farm dogs (51%, 51/100) (P<0.001) and lower in household dogs (2.9%, 3/102) (P<0.0001). The seroprevalence in hunting (23%, 23/100) and stray (24.5%, 23/94) dogs was moderate, and no significant differences were observed between these two populations (P>0.05). A significantly higher number of dogs showed titres of 1:50-1:100 (68%, 68/100) than >or=1:200 (33%, 33/100) titres (P<0.0001). N. caninum antibodies were more often detected in mixed breed than pure breed dogs (P<0.01), but when data were stratified by dog type a significant association was not found (P>0.05). A significantly higher prevalence of N. caninum was observed in dogs over 1 year old (P<0.01), indicating that horizontal transmission may be the most important route of infection. The presence of N. caninum antibodies was significantly more frequent in Leishmania infantum-seropositive hunting (P<0.05) and stray dogs (P<0.00001). This study confirms that farm, stray and hunting dogs can be considered at-risk dog populations for N. caninum infection in Spain.  相似文献   
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