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1.
The purpose of this study was to examine changes in myosin heavy chain (MHC) composition due to chronic clenbuterol administration with or without exercise in mares. Unfit Standardbred mares (aged 10+/-3 years) were divided into four groups: clenbuterol (2.4 micro/kg BW twice daily) plus exercise (3 days/week for 20 min at 50% VO(2max); CLENEX; n=6), clenbuterol only (CLEN; n=6), exercise only (EX; n=5), and control (CON; n=6). Muscle biopsies were obtained from gluteus medius muscle before and after the eight-week training/administration period. MHC composition was determined via SDS gel electrophoresis and quantified using a scanning and densometric system.CLENEX and CLEN exhibited significant (P<0.05) MHC changes while EX and CON did not. MHC type IIA decreased (29.8+/-6.1 to 19.3+/-4.0%, CLENEX; and 36.8+/-12.4 to 26.4+/-7.9%, CLEN) and MHC type IIX increased (59.4+/-7.2 to 71.8+/-5.8%, CLENEX; and 50.5+/-12.5 to 62.0+/-9.3%, CLEN). Chronic clenbuterol administration with and without exercise resulted in a significant shift in MHC profile in Standardbred mares.  相似文献   

2.
OBJECTIVE: To determine the growth-related changes in metabolic and anatomic properties in equine muscle fiber type, including hybrid fibers identified with immunohistochemical analysis. ANIMALS: 24 2-, 6-, 12-, and 24-month-old female Thoroughbreds. PROCEDURE: Samples were obtained from the gluteus medius muscle of all horses. Expression of myosin heavy chain (MHC) isoforms MHC-I, -IIa, -IIb, and -IIx in each muscle fiber was detected by use of 4 primary monoclonal antibodies: BA-D5, SC-71, BF-F3, and BF-35, respectively. Five muscle fiber types (types I, I/IIA, IIA, IIA/IIX, and IIX) were immunohistochemically identified. The area and activity of succinic dehydrogenase (SDH) in each fiber type were determined by use of quantitative histochemical staining and image analysis. RESULTS: Although the proportion of type I and IIX fibers did not change with age, the proportion of type IIA and IIA/IIX fibers significantly increased and decreased, respectively, from 2 months to 24 months of age. The increase in proportion of type IIA fibers with growth may have been attributable to muscle fiber-type transition from type IIA/IIX fibers but not from type IIX fibers. Values for SDH activity and fiber area in hybrid fiber types were intermediate to those for their respective pure phenotypes. CONCLUSIONS AND CLINICAL RELEVANCE: Hybrid fibers have an important role for determining the proportion of muscle fiber type in horses < 24 months old, and the metabolic and anatomic properties of the hybrid fibers are well coordinated, as in mature horses.  相似文献   

3.
Low birth weight (LBW) as a result of restricted fetal growth increases the risk for later metabolic diseases and adiposity. However the relationship between LBW and postnatal growth and adult body composition has not been fully investigated. We have used sheep to determine the effects of LBW on postnatal growth and body composition at maturity. LBW was induced by twinning and placental embolization. At birth, LBW lambs were 38% lighter than controls (2.8 +/- 0.2 vs 4.4 +/- 0.3 kg, P<0.05), but had caught up in bodyweight by 8 weeks after birth. At approximately 2.3 years, bodyweights were not different between groups, but there were reductions in absolute (-8%) and relative (-17%) brain weights of LBW sheep (P<0.05) compared to controls. X-ray absorptiometry showed that the mature LBW sheep, compared to controls, had greater amounts of lean muscle (38.1 +/- 1.3 vs 35.3 +/- 0.5 kg, P<0.05) and tended to have more body fat (12.2 +/- 1.2 vs 9.6 +/- 0.9 kg; P=0.1); at autopsy abdominal fat mass was greater in LBW sheep (3.06 +/- 0.26 vs 2.20 +/- 0.25 kg, P<0.05). Plasma leptin concentrations were not different between groups. We conclude that, in sheep, LBW is associated with early postnatal catch-up in body weight, but body composition is permanently altered such that, relative to controls, adiposity is increased and brain weight is decreased.  相似文献   

4.
Skeletal muscle constitutes the largest organ system in the mammalian body and is essential for movement and force generation. Muscle tissue has the unique ability to adapt and remodel with regular exercise. Adaptation of equine contractile apparatus to exercise training with a different character occurs at the structural to the cellular and molecular levels and depends on age, breed, and sex. In Andalusian and Arabian horses from 3 months to 24 years of age, it was found that the mean cross-sectional area occupied by IIA and IIX fibers was greater in stallions than in mares. In muscle of Dutch Warmblood foals from birth to 1 year of age, a significant number of fibers coexpress either developmental and type IIa or cardiac–alpha and type I myosin heavy chain (MyHC) isoforms. Endurance training results in increased mitochondrial density, capillary supply, changes in key metabolic enzymes, and increased maximal oxygen uptake and promotes a transition from type II to type I muscle fiber. In horses, prolonged aerobic exercise training has been shown to induce a further decline in the percentage of type IIx MyHC isoform expression and an increase of type I and IIa MyHC isoform expression. Short-duration, high-intensity exercise training stimulates type IIA and hybrid (IIA/IIX) fibers. Therefore, intensive high-speed trotting facilitates muscle fiber hypertrophy and increases the oxidative capacity of type IIX fibers.  相似文献   

5.
To consider the optimal training programme for Thoroughbred horses, we examined the recruitment pattern of muscle fibres including hybrid muscle fibres in well-trained Thoroughbred horses. The horses performed exercise at three different intensities and durations; i.e., 100% VO2max for 4 min, 80% and 60% VO2max for 8 min on a treadmill with 10% incline. Muscle samples were obtained from the middle gluteal muscle before, during (4 min at 80% and 60% VO2max), and after exercise. Four muscle fibre types (types I, IIA, IIA/IIX, and IIX) were immunohistochemically identified, and optical density of periodic acid Schiff staining (OD-PAS) in each fibre type, and the glycogen content of the muscle sample, were determined by quantitative histochemical and biochemical procedures. The changes in OD-PAS showed that the recruitment of all fibre types were identical at the final time stage of each exercise bout, i.e., 4 min running at 100% VO2max, and 8 min running at 80% and 60% VO2max. The changes in OD-PAS of type IIA/IIX fibre were very similar to those of type IIX fibre. The recruitment of these fibres were obviously more facilitated by 4 min running at 100% VO2max than by 4 min running at 80% or 60% VO2max. Short duration with high intensity exercise, such as 4 min running at 100% VO2max or 8 min running at 80% or 60% VO2max, is effective to stimulate type IIX fibre and IIA/IIX fibres that have the fastest speed of contraction.  相似文献   

6.
Mammalian skeletal muscle expresses splice variants of neuronal nitric oxide synthase (nNOS). Skeletal muscles have a metabolically heterogeneous population of myofibers, and fiber composition in equine skeletal muscle is correlated with athletic ability in endurance events. In this study, we investigated whether nNOS expression in equine skeletal muscle is related to fiber type and endurance training. Biopsy samples obtained from the gluteus medius of sedentary- (SH) and endurance-trained (TH) horses were examined for the electrophoretic mobility of myosin heavy chain (MHC) and NOS activity. Serial tissue cross-sections were stained for myosin ATPase and nicotinamide adenine dinucleotide (NADH) reductase, and also immunostained for nNOS. The gluteus medius of TH had higher levels of nNOS expression and activity when compared to muscle from SH. In SH, nNOS was restricted to the subsarcolemmal area while in TH nNOS was also present at cytoplasmic sites. A splice variant of nNOS was heterogeneously distributed among the different myofibers, its expression being higher in fast-oxidative-glycolytic type IIA fibers than in fast-glycolytic type IIX fibers and absent in slow-twitch type I fibers. Trained horses had a significantly higher relative content of type IIA fibers, a greater oxidative capacity, and a lower percentage of type IIX fibers when compared with SH. The differences in muscle fiber typing between the 2 groups of horses reflected alterations that probably resulted from the endurance-training program. Overall, these results show that nNOS is differentially expressed and localized in the gluteus medius according to the fiber type and the athletic conditioning of the horses.  相似文献   

7.
This study examined whether body composition was predictive of competitive success in elite standardbreds (STB). Rump fat and muscle thickness (MTH) (vastus lateralis/intermedius [VL], extensor carpi radialis [ECR]) were measured in vivo in male n=6; female n=8 by B-mode ultrasound. Percentage body fat (%fat) was calculated from rump fat. There were no gender differences for age, body mass (males 432+/-11 kg; females 443+/-13 kg), fat-free mass (FFM) (males 400+/-12 kg; females 400+/-11 kg), ECR MTH (males 61+/-2 cm; females 60+/-2 cm) or race time (RT) (males 113+/-3 s; females 114+/-2 s). Males had less (P<0.05) fat mass (males 32+4 kg; females 44+/-3 kg) and %fat (males 7.4+/-0.9%; females 9.9+/-0.5%) and larger (P<0.05) VL MTH (males 88+/-7 cm; females 81+/-3 cm). RT was correlated to %fat and fat mass in males (r=0.89; r=0.82, P<0.05) not females (r=0.51; r=0.14). FFM tended to relate to RT in males (r=-0.76, P=0.07) and females (r=-0.59, P=0.12). Combined %fat and FFM data were correlated to RT (%fat r=0.70, P<0.01; FFM r=-0.65, P<0.01). RT was not correlated to MTH (VL r=-0.28; ECR r=-0.31). In conclusion, FFM was related to RT in elite STB with %fat negatively related to RT in males.  相似文献   

8.
Twenty crossbred yearling steers (421 kg) were used to evaluate the effects of implanting with trenbolone acetate (TBA; 120 mg), estradiol-17β (E(2); 25.7 mg), and a combination (120 mg of TBA and 24 mg of E(2)) on adipogenic and myogenic mRNA concentrations. Animals were blocked by BW and within each block were assigned to 1 of 4 treatments. Animals were housed and fed in individual pens with 5 animals per treatment. All animals were weighed weekly, and muscle biopsy samples were taken from the LM of each steer on d 0 (before implantation), 7, 14, and 28. Total RNA was isolated from each sample and real-time quantitative PCR was used to measure the quantity of C/EBPβ, PPARγ, stearoyl CoA desaturase (SCD), myogenin, and 3 isoforms of bovine myosin heavy chain (MHC) mRNA. Total BW gain from the 28-d period was adjusted to d 0 by use of covariant analysis, and steers in the implant groups tended (P = 0.09) to have increased BW gain compared with nonimplanted control steers. Analysis of the gene expression of MHC showed that neither implant nor day (P > 0.20) had a significant effect on the expression of type I or IIX MHC mRNA There was also no treatment effect (P > 0.20) on MHC-IIA and myogenin, but increasing days on feed increased (P = 0.05) the expression of MHC-IIA mRNA. Relative mRNA abundance of C/EBPβ, PPARγ, and SCD increased (P < 0.05) during days of feed but PPARγ decreased (P < 0.05) with the treatment of combined TBA/E(2) implant. Results of this study indicate that implanting with TBA, E(2), or both increased BW gain and decreased adipogenic gene expression of finishing steers without significantly affecting the concentration of type I, IIA, or IIX MHC mRNA. Increasing days on feed increased both MHC-IIA and adipogenic gene expression in bovine skeletal muscle biopsy samples. We conclude that administration of steroidal implants had no effect on the proportion of the 3 MHC mRNA isoforms but decreased C/EBPβ, PPARγ, and SCD mRNA in bovine skeletal muscle.  相似文献   

9.
Twenty-six 6-week old female New Zealand White rabbits were divided into two groups: ad libitum (AL) and 70% restricted (RS) feeding. At the beginning of the experiment the liveweights were practically the same: 0.99 +/- 0.08 vs. 1.01 +/- 0.08 kg in group AL and RS, respectively. At 18 weeks of age the body weight of Group RS rabbits was 84.7% (3.14 +/- 0.24 kg) of the group AL (3.71 +/- 0.31 kg). The apparent digestibility of crude protein was significantly (p < 0.001) higher in Group RS than in Group AL (76.5 +/- 1.4 vs. 73.0 +/- 2.7%). The daily water consumption was significantly (p < 0.05) higher (3.5 ml/g DM intake) in Group RS as compared to Group AL (1.9 ml/g DM). Since the average body weight in Group RS at 18 weeks was the same as that of Group AL at 14 weeks of age (3.14 kg), the comparison of the live body measures and indices was based on these ages. Animals fed ad libitum or restricted show no differences at the defined age in most live body measurements except in heart girth and rump width, which were significantly (p < 0.05) shorter in Group AL than in Group RS (29.3 +/- 0.8, 5.7 +/- 0.5 and 30.7 +/- 1.0, 6.2 +/- 0.3 cm, respectively). Body capacity was significantly (p < 0.05) smaller in Group AL, as the head capacity-body capacity proportion was significantly (p < 0.05) higher in Group AL than in Group RS (1653.1 +/- 134.5, 22.0 +/- 2.5 and 1913.7 +/- 168.7, 17.7 +/- 1.9, respectively). Due to restricted feeding the growth of the head proved to be less intensive than that of the body at the same body weight. The body in these does tended to be wider. Since the head in comparison to length or capacity of the body was smaller in does fed 70% of ad libitum, it could be concluded that the development of body parts of restricted-fed does was unequal (allometric growth). The effect of feed restriction reflected in lower dry matter and fat, and a higher ash and protein content both in total body and in dry matter composition of rabbits at 18 weeks of age. Restricted feeding delayed sexual maturity (69 vs. 92% of rabbits) with later starting ovarian activity, weaker ovarian responsiveness, and a smaller number of tertiary follicles on the ovarian surface.  相似文献   

10.
A high dietary fat intake may be an important environmental factor leading to obesity in some animals. The mechanism could be either an increase in caloric intake and/or a decrease in energy expenditure. To test the hypothesis that high fat diets result in decreased resting energy expenditure (REE), we measured REE using indirect calorimetry in 10-adult intact male Labrador Retrievers, eating weight-maintenance high-fat (HF, 41% energy, average daily intake: 8018 +/- 1247 kJ/day, mean +/- SD) and low-fat (LF, 14% energy, average daily intake: 7331 +/- 771 kJ/day) diets for a 30-day period. At the end of each dietary treatment, body composition measurements were performed using dual-energy X-ray absorptiometry. The mean +/- SD REE was not different between diets (4940 +/- 361 vs. 4861 +/- 413 kJ/day on HF and LF diets respectively). Measurements of fat-free mass (FFM) and fat mass (FM) also did not differ between diets (FFM: 26.8 +/- 2.3 kg vs. 26.3 +/- 2.5 kg; FM: 3.0 +/- 2.3 vs. 3.1 +/- 1.5 kg on HF and LF diets respectively). In summary, using a whole body calorimeter, we found no evidence of a decrease in REE or a change in body composition on a HF diet compared with LF diet.  相似文献   

11.
12.
A study of the effects of conjugated linoleic acid (CLA) on the belly firmness and fatty acid composition of genetically lean pigs was conducted. From 75 to 120 kg live weight, 30 gilts were allowed ad libitum access to a corn-soybean meal diet supplemented with either 1% CLA oil (CLA-60) or 1% sunflower oil (SFO) or were fed the sunflower oil-supplemented diet restricted to the amount consumed by pigs fed the CLA-60 diet (RSFO). Conjugated linoleic acid oil consists of 60% positional and geometric isomers of CLA. Pigs fed SFO exhibited higher average daily gains (0.98 vs 0.80 kg/d, P < 0.01) than RSFO-fed pigs, but there were no effects of dietary treatment on feed intake or feed efficiency. Dietary treatment did not affect (P > 0.05) backfat thickness or longissimus muscle area. Bellies of gilts fed CLA-60 were subjectively evaluated to be firmer (2.91 vs 2.43 or 2.07 +/- 0.13, P < 0.01) than those of SFO- or RSFO-fed gilts, respectively. The longissimus muscle of gilts fed CLA-60 contained more saturated fatty acids (39.77 vs. 36.04 or 36.73 +/- 0.74%, P < 0.001) and less unsaturated fatty acids (60.23 vs 63.96 or 63.27 +/- 0.74%, P < 0.001) than that of gilts fed SFO or RSFO, respectively. The belly fat of gilts fed CLA-60 contained more saturated fatty acids (44.45 vs. 37.50 or 36.60 +/- 0.46%, P < 0.001) and less unsaturated fatty acids (54.78 vs. 61.75 or 62.47 +/- 0.46%, P < 0.001), resulting in lower iodine values (57.69 vs 66.37 or 65.62 +/- 0.91, P < 0.001) than that of gilts fed SFO or RSFO, respectively. Gilts fed CLA-60 accumulated more CLA in the longissimus muscle (0.55 vs 0.09 or 0.09 +/- 0.03%, P < 0.01) and belly fat (1.56 vs. 0.13 or 0.13 +/- 0.15%, P < 0.001) than did gilts fed SFO or RSFO, respectively. Dietary treatment did not affect (P > 0.05) 24-h pH, drip loss or subjective quality evaluations of the longissimus muscle. The effect of supplemental CLA to improve belly firmness is of practical significance and may provide a nutritional solution to carcass fat and belly firmness problems, thereby enhancing the overall value of extremely lean carcasses.  相似文献   

13.
The objective of this experiment was to determine if growth, carcass composition, and myofiber characteristics of lambs were affected by heterozygosity for a myostatin mutation (g+6723G>A) when offered differing allowances of feed administered with or without ractopamine. Heterozygote [MSTN A/G (n = 40)] and homozygote wildtype [MSTN G/G (n = 39)] castrate male lambs were individually fed ad libitum (HI; 1.8 × estimated ME(m)) or a restricted allowance (LO; 1.1 × estimated ME(m)) of a diet (191 g of CP/kg of DM and 12 MJ of ME/kg of DM), supplemented with (0.4 mg/kg of BW) or without the β-adrenergic agonist ractopamine (RAC or NO RAC) for 47 d. The lambs were scanned by computed tomography at the beginning and completion of the feeding experiment to calculate composition of lean, fat, and bone in the carcass component of the body. The MSTN A/G HI intake lambs had significantly greater total daily carcass growth (P = 0.045) and loin eye depth (P = 0.022) and tended to have a greater daily growth of lean (P = 0.09) in the carcass, compared with MSTN G/G HI intake lambs. Conversely, MSTN A/G LO intake lambs tended to have less daily lean deposition (P = 0.09), significantly less total daily carcass growth (P = 0.045), and had a greater percentage of type IIX myofibers (P < 0.01) and total myofiber area (relative area) of type IIX myofibers (P = 0.013). The inclusion of RAC increased final BW (P = 0.03) and ADG (P = 0.02), percentage of type IIC (P < 0.001) and IIA (P = 0.012) myofibers, cross-sectional area of types I (P = 0.04) and IIAX (P = 0.04) fibers, and the relative area of type IIC (P = 0.003) and IIA (P = 0.01) myofibers in the LM. The experiment demonstrated that including RAC in the diet of lambs increased final BW and ADG, but not HCW, and increased proportion of type IIC and IIA myofibers and cross-sectional area of type I and IIAX myofibers. Our data suggest that RAC and the heterozygous myostatin mutation act together to increase growth of muscle on a high plane of nutrition. The experiment also demonstrated that poor nutritional background of lambs heterozygous for the myostatin mutation may negatively influence their growth rates and myofiber characteristics.  相似文献   

14.
Eighteen pregnant mares were randomly allotted to one of two treatment groups. The control group was fed a conventional concentrate and the fat group was fed a concentrate containing 5% feed-grade rendered fat. Both concentrates had the same nutrient:calorie ratio and were fed in amounts required to maintain zero change in percent body fat of the mares. During the study, which began 60 d prior to expected foaling date and ended 60 d postpartum, mares were monitored for feed intake, body weight, rump fat thickness, ration digestibility, plasma glucose and lipid concentrations, milk composition and reproductive efficiency. Birth weight, growth rate, and plasma glucose and lipid concentrations were also measured in foals. Mares fed fat consumed less concentrate (P<.09 during the last 60 d of gestation but consumed similar amounts of concentrate over 60 d of lactation. Protein and ether extract digestion was higher (P<.05 and P<.09, respectively) in the mares fed fat during the postpartum period. Dietary treatment had no influence on plasma glucose or lipid concentrations of the mares or plasma glucose concentrations of their foals, but foals whose dams were fed fat had higher plasma lipid concentrations at birth (P<.01), d 10 and d 30 (P<.05). Percent fat was higher in milk samples from mares fed fat at d 10 (P<.09, 1.23 vs .99%) and d 60 (P<.01, .72 vs .43%) of lactation. Reproductive performance was not significantly different between treatment groups, however there was a trend for a shorter postpartum interval and fewer cycles per pregnancy in the mares fed added fat. Foals from both groups were of similar size and weight at birth and had similar weight gains over 60 d, however, foals nursing mares fed fat tended to gain more weight in the first week of life (1.85 vs 1.56 kg/d) and have more rump fat at d 60 (.53 vs .44 cm) than foals nursing control mares.  相似文献   

15.
Ractopamine-HCl (RAC) is a beta-adrenergic agonist with variable effects on cattle performance and carcass variables. Cull cows fed RAC (200 mg . head(-1) . d(-1)) demonstrate an increased size of type I and II muscle fibers that does not translate into a larger ribeye area. The objective of this study was to examine the dose-dependent effects of RAC on cull cow muscle morphometrics. Eighty-eight cull beef cows representing 2 breed types (n = 44 each) were fed 0, 100, 200, and 300 mg . head(-1) . d(-1) of RAC for the last 28 d of a 54-d feeding period. On d 54, cows were slaughtered, and samples of the LM and semimembranosus muscle (SM) from 16 randomly selected carcasses (n = 4 per treatment) were taken for measurement of beta (2)-adrenergic receptors and type I, IIA, and IIX myosin heavy chain (MyHC) gene expression. Twenty-four hours postmortem, LM, SM, infraspinatus (INF), and vastus lateralis samples from 40 randomly selected carcasses (n = 10 per treatment) were obtained and frozen for immunohistochemical analysis. Muscle fiber cross-sectional area and diameter, MyHC isoform expression, and fiber-associated nuclei numbers were measured. Ractopamine dosage exhibited differential effects on muscle morphometrics and MyHC gene expression. Muscle fiber cross-sectional area and diameter were increased (P < 0.05) by RAC in INF type I and IIA fibers and SM type IIA fibers. Ractopamine increased (P < 0.05) MyHC type IIX mRNA and tended to increase (P < 0.10) beta(2)-adrenergic receptors in the SM; a change in mRNA abundance was not detected for either gene in the LM. Treatment with RAC decreased (P < 0.05) fiber-associated nuclei numbers in the INF, vastus lateralis, and LM but did not affect (P > 0.05) MyHC or beta-adrenergic receptor expression. These results indicate that cull cow feeding programs may consider supplementing RAC as a means of adding value to cuts within the chuck, such as the INF.  相似文献   

16.
Carcass composition and meat quality attributes of 55 suckling kids (27 males and 28 females) and 57 suckling lambs (28 males and 29 females) of Portuguese native breeds were investigated. These suckling kid and lamb meats are European meat quality labels produced according to "Cabrito de Barroso- PGI" and "Borrego Terrincho-PDO" specifications, respectively. Female kids were slaughtered at 9.1 +/- 0.36 kg of BW, and male kids were slaughtered at 10.4 +/- 0.37 kg of BW, corresponding to 20.1 and 17.7% of maturity, respectively. Female lambs were slaughtered at 8.6 +/- 0.53 kg of BW, and male lambs were slaughtered at 9.9 +/- 0.23 kg of BW, corresponding to 19.9 and 17.1% of maturity, respectively. At 24 h postmortem, various yield and quality measurements were collected. The left sides of the carcasses were dissected into muscle, subcutaneous fat, intermuscular fat, and bone. Final pH, instrumental color (L*, a*, b*), carcass measurements, and kidney knob and pelvic fat were also determined. Samples of LM were taken from the lumbar and thoracic cuts for intramuscular and meat quality determinations. At 72 h postmortem, a sample of LM was used for cooking losses and Warner-Bratzler shear force determination. Suckling lambs had greater dressing proportion than suckling kids (P < 0.01). Carcass fatness was not affected by species (P > 0.05), but females had greater kidney knob and pelvic fat proportion than males (P < 0.01). Lambs had greater proportions of the highly valued leg cut and lower proportions of shoulder, anterior rib, and neck cuts than kids. Dissection results indicated that kid carcasses had greater muscle content and lower dissected fat and bone than lambs. Kids had greater (P < 0.001) muscle ultimate pH value than lambs (5.8 +/- 0.02 vs. 5.6 +/- 0.02). Males had greater (P < 0.05) muscle ultimate pH value than females (5.7 +/- 0.02 vs. 5.6 +/- 0.02). The kid meat was significantly lighter (P < 0.05) and less yellow (P < 0.001) than the lamb meat. Kids presented less cooking losses (P < 0.001) than lambs, and shear force value was significantly greater (P < 0.01) in lamb meat. The kid meat had significantly more moisture (P < 0.001) and less intramuscular fat content (P < 0.001) than lambs. At this maturity stage, there were significant differences on both carcass and meat quality attributes of suckling kids and lambs, possibly due to inherent differences between species.  相似文献   

17.
Fibre type composition, activities of enzymes such as citrate synthase (CS), 3-hydroxyacyl coenzyme A dehydrogenase (HAD), lactate dehydrogenase (LDH), as well as glycogen, lactate and pH levels were analysed in muscle biopsies (m. gluteus medius) obtained after bullfighting from 10 young and 10 old bulls. No changes were seen in fibre type composition between groups, but the older bulls had higher HAD and LDH activities. Low glycogen concentrations and low pH values were found in both groups, but the lactate concentration after bullfighting was higher in the older group of bulls. The histochemical stain for glycogen revealed that type IIB fibres in both young and old bulls contained more glycogen than seen in type IIA and type I fibres. These results show that young and old bulls have similar muscle fibre type composition, but the metabolic capacity differs, with a higher glycolytic capacity and lactate production in older bulls. Furthermore, it seems that the physical and emotional stress in connection with a bullfight causes a marked depletion of glycogen, especially of type I and IIA fibres.  相似文献   

18.
To evaluate embryo transfer as a possible method to circumvent infertility in mares, embryos from 14 normal and 14 infertile mares were collected three times and examined. Fewer flushes (p less than 0.05) from normal than infertile mares (1/42 vs 9/42) contained only abnormal embryos whereas more flushes (p less than 0.05) from normal than infertile mares contained one or more normal embryos (28/42 vs 8/42). More flushes (p less than 0.05) from normal than infertile mares contained embryos (29/42 vs 17/42). The embryo diameters (mm) at either day-7 or day-8 post ovulation were greater (p less than 0.01) for normal than infertile mares (day 7: 07 +/- 0.08 vs 0.3 +/- 0.07; day 8: 1.1 +/- 0.18 vs 0.7 +/- 0.23). Six of the 10 (60%) flushes that contained only abnormal embryos were recovered from ares with positive uterine cultures or moderate to severe endometritis. The embryos recovered from normal mares were greater in quantity and better in quality.  相似文献   

19.
One hundred sixty-eight crossbred steers (317.1 +/- 1.0 kg) were used to evaluate the effects of supplemental fat in finishing diets on the fatty acid composition, including the 9,11 isomer of conjugated linoleic acid, of beef. Steers were allotted within three weight blocks to a randomized complete block design with a 3 x 2 + 1 factorial arrangement of dietary treatments. Main effects were level of yellow restaurant grease (RG; 0, 3, and 6%), and level of alfalfa hay (AH; 3.5 and 7%) with an added treatment containing 6% tallow (T) and 7% AH in barley-based diets containing 15% potato by-product and 7% supplement (all dietary levels are on a DM basis) fed for an average of 165 d. Fatty acids of the LM and s.c. fat from four randomly selected steers per pen were quantified using GC after methylation with sodium methoxide. Dietary treatment did not (P > 0.10) affect total fatty acid (FA) content of the LM (143 +/- 5.2 mg/g) or fat (958 +/- 7.9 mg/g). Myristic acid increased linearly (P < 0.01) with increasing RG from 3.1 to 3.7 +/- 0.1 g/100 g of FA in muscle. Stearic acid increased linearly (P < 0.05) as RG increased in the diet, from 11.4 to 12.9 +/- 0.4 g/100 g of FA in LM and from 9.9 to 12.2 +/- 0.3 g/100 g of FA in fat. Compared with T, steers fed 6% RG had more (P < 0.05) oleic acid in LM (42.7 vs. 40.3 +/- 0.5 g/100g FA) and in fat (43.0 vs. 40.9 +/- 0.5 g/100g FA). The cis-9, trans-11 conjugated linoleic acid (CLA) increased quadratically (P < 0.01) with increasing dietary RG in LM from 0.45 to 0.64 to 0.62 +/- 0.03 g/100 g of FA and increased in fat from 0.61 to 0.84 to 0.83 +/- 0.04 g/100 g of FA. Moreover, cis-9, trans-11 CLA was higher (P < 0.05) in fat from steers fed RG compared with T (0.81 vs. 0.69 +/- 0.04 g/100 g of FA), and tended to be higher (P = 0.07) in muscle (0.62 vs. 0.54 +/- 0.03 g/100 g of FA. Feeding yellow restaurant grease increased content of cis-9, trans-11 CLA in beef without an increase total FA content.  相似文献   

20.
The venous plasma concentrations of mepivacaine were determined in 7 adult mares (420 +/- 17.1 kg) given an injection of a 2% solution of the hydrochloride at either the sacral (S2-3 to S5-C1) epidural space or the midsacral (S2-3) subarachnoid space. An average dose of 91.4 +/- 15.7 mg (4.6 +/- 0.8 ml) was needed to produce caudal epidural analgesia (CEA) and 26.7 +/- 5.4 mg (1.3 +/- 0.3 ml) to produce caudal subarachnoid analgesia (CSA). Maximal caudal analgesia extended from spinal cord segments S-1 to coccyx during CEA and CSA. The onset of analgesia as measured by response to superficial and deep muscular pinprick stimulations was significantly (P less than 0.05) faster in mares with CSA than with CEA (8.3 +/- 2.4 minutes vs 21.4 +/- 3.8 minutes). The period of analgesia was significantly (P less than 0.05) longer in mares with CEA than with CSA (80.0 +/- 11.5 minutes vs 67.4 +/- 26.3 minutes). The rate of vascular absorption of mepivacaine from the epidural space was significantly (P less than 0.05) faster than from the subarachnoid space. Maximum venous plasma concentrations of mepivacaine were similar (P greater than 0.05) after epidural and subarachnoid injections (0.05 +/- 0.03 micrograms/ml and 0.05 +/- 0.03 micrograms/ml) at the same times after mepivacaine administration (51.4 +/- 33.4 minutes and 53.6 +/- 24.3 minutes).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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