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1.
Boer (n = 132), Kiko (n = 92), and Spanish (n = 79) straightbred does were studied across 6 yr to assess doe fitness on southeastern US pastures. Does were exposed to Boer, Kiko, and Spanish bucks in a complete 3-breed diallel mating scheme each fall for spring kidding in March or May. A total of 1,041 doe-yr units were observed with does (ranging from 2 to 8 yr of age) managed together in a semi-intensive manner. The proportion of buck-exposed does delivering at least 1 live kid was less (P < 0.01) for Boer does (80%) than for Kiko (96%) and Spanish does (94%). Litter size and litter weight at birth were not affected (P > 0.15) by breed of dam. By weaning at 3 mo, the proportion of available does weaning at least 1 kid was less (P < 0.01) for Boer does (53%) than for Kiko (84%) and Spanish does (82%). For does weaning kids, litter size at weaning was greater (P = 0.01) for Spanish does (1.74 kids) than for Kiko (1.59 kids) and Boer does (1.47 kids). Litter weaning weight was lighter (P < 0.01) for Boer dams (23.0 kg) than for Kiko (27.2 kg) and Spanish dams (26.5 kg). The efficiency ratio of litter weight to dam weight at weaning differed (P < 0.05) among all 3 dam breeds: Boer = 51%; Kiko = 62%; Spanish = 68%. Annual rates of lameness, endoparasitism, and attrition, respectively, were greater (P < 0.01) for Boer does (69, 53, and 28%) than for Kiko (32, 24, and 10%) and Spanish does (42, 22, and 11%). Postpartum fecal egg counts for endoparasite loads were less (P < 0.05) for Spanish dams (346 eggs/g) than for Kiko (524 eggs/g) and Boer does (675 eggs/g). Whole-herd annual doe productivity based on all available does was less (P < 0.01) for Boer does (11.7 kg weaned/doe) compared with Kiko (22.0 kg weaned/doe) and Spanish does (21.1 kg weaned/doe). Boer does expressed substantially decreased levels of fitness compared with Kiko and Spanish does when semi-intensively managed on humid, subtropical pasture. Kiko and Spanish should be preferred as maternal breeds in meat goat production systems under conditions reflective of this study.  相似文献   

2.
为探索母羊因素对哺乳期云上黑山羊羔羊生长发育的影响,根据母羊体重、胎次分别选取云上黑山羊初生羔羊90只和120只,公、母各半,从出生开始直至90日龄断奶,每10天进行1次体重测定,进行生长发育分析.结果表明:①母羊产后体重对羔羊初生重、哺乳期体重具有显著影响(P<0.05).母羔中,38～45 kg母羊组和48～62 ...  相似文献   

3.
This study was undertaken to determine some blood and other physiological parameters with potential for use as prognostic indicators of viability of newborn goat kids. Of the 143 kids born during the on-farm study, 97 were crosses of Galla x Small East African (SEA) and 46 were pure SEA. The SEA x Galla kids were 46 single males, with a mean body weight at birth of 2.77 +/- 0.22 kg, 43 females with a mean body weight at birth of 2.36 +/- 0.76 kg and 5 and 3 sets of female and male twins (mean body weight at birth of 1.8 +/- 0.19 kg and 2.05 +/- 0.07 kg for the female and male kids, respectively). The SEA kids comprised 36 single male and female kids (mean body weight at birth of 2.48 +/- 0.04 kg and 10 sets of twins (both male and female) (mean body weight at birth of 1.50 +/- 0.04 kg ). Pre-suckling sera obtained on-station from kids born of does vaccinated against Escherichia coli (n = 8) and unvaccinated does (n = 7) had a total protein content of <40.0 g/l and no detectable levels of IgG and A or E. coli antibodies. Sera obtained 12 hours post partum) from kids that survived in both groups contained about 19-22 g of Ig g/l, 50-80 g total protein/l, blood glucose of >5 mmol/l and had an E. coli antibody titre of between 1/160 and 1/640. On the other hand, kids that died within 48 hours of birth (parturient deaths) and had been classified in categories 3 and 4 righting reaction had low (<40 g/l) total protein, low white blood cell count (4,000/ml) and low blood glucose concentration (<4.9 mmol/l). It is concluded that kids with delayed righting reaction (>45 minutes), low rectal temperature (<36 degrees C), low birth weights (<1.5 kg for singles and <1.0 kg for twins), low white blood cells (<4,000/ml), low (<2 mmol/l) blood glucose levels, low total protein (<40.0 g/l), low (<1:160) E. coli antibody titre and IgG (< or =3,350 mg/l) in sera obtained 12 hours after birth have a poor prognosis for survival.  相似文献   

4.
The effects of diet and climate were assessed in 42 light horse weanlings over 30 wk. Horses were fed diets varying in energy and phosphorus content. Diets were predominantly forage (73 to 77.5%) or concentrate (62 to 62.25%) and had 2.65 or 3.09 Mcal DE/kg DM, respectively. Horses were weighed every 14 d. Group feed intakes and climatic variables were recorded daily. Dietary phosphorus content did not affect intake or gain. Horses fed forage diets ate 18% more (P less than .001) DM than horses fed concentrate, but DE intakes did not differ. Average DE intakes, 21.5 Mcal daily, were 33% more than those given in 1978 National Research Council (NRC) tables. Overall ADG by forage- and concentrate-fed horses were .83 and .89 kg, respectively. These values were 23 and 32% above mean ADG values given for horses at 6 and 12 mo in 1978 NRC tables. Average daily gain declined (P less than .01) with age, although daily DE intake increased (P less than .01). Total DM and DE intakes were determined largely by body weight, but age was the main determinant of weight-scaled DE intake. Weight- and age-scaled DE intakes were reduced (P less than .001) by 6.1% at temperatures below -10 degrees C compared with temperatures above -10 degrees C. Temperatures below -20 degrees C had no greater effect on DE intake than those between -10 to -20 degrees C. Neither precipitation nor wind alone affected weight- and age-adjusted DE intake. In conclusion, weanling horses fed readily digested diets ad libitum gained weight at or above expected values even at severely cold ambient temperatures.  相似文献   

5.
Two experiments were conducted to determine the physiological responses of consuming a fungus-free (FF) or fungus-infected (INF) tall fescue diet (Exp. 1) or the FF diet plus ergotamine tartrate at 30 ppm (FF/ET, Exp. 2) in a thermoneutral (21 degrees C) or heat-stressed environment (32 degrees C, dry bulb; 10 degrees C dew point). Treatment periods lasted 28 d after a 10-d adaptation period. Experiment 1 was replicated three times, and Exp. 2 was replicated twice, with eight Holstein steers in each replicate (mean BW = 185 kg). Feed intake (FI), rectal temperature (RT), and respiration rate (RR) were recorded daily, and heart rate (HR) and infrared temperatures at the ear canal (ECT), ear tip (ETT), pastern (PT), coronary band (CBT), and tail tip (TTT) were recorded weekly. Consumption of INF and FF/ET compared with FF diets decreased (P less than .10) FI, HR, ECT, PT, CBT, and TTT and elevated (P less than .10) RT and RR by 2.8, 2.77 kg/d; 17, 23 beats/min; .8, 1.1 degrees C; .9, 1.1 degrees C; .8, .9 degrees C; 1.1, 2.6 degrees C; .3, .5 degrees C; and 8, 8 breaths/min; respectively. Ear-tip temperature was reduced (P less than .10) 1.6 degrees C by consumption of INF but not by consumption of FF/ET. Reduction of peripheral temperatures is indicative of reduced blood flow to peripheral areas as a result of vasoconstriction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

6.
The objectives were to investigate if partial substitution of a grazing diet with a supplemental high-starch feed during the last 12 d of gestation improved colostrum yield and neonatal activity in goat does grazing semi-arid rangeland. For the first objective, 25 pregnant does were randomly assigned to 1 of 2 treatments: 1) grazing only (control; n = 11), and 2) grazing plus 0.6 kg/d of supplemental corn (as fed), a high starch feed, during the last 12 ± 1.0 d before parturition (SC; n = 14). Colostrum was collected at parturition and again at 1, 3, 6, and 10 h postpartum for yield and composition. In all goats, blood concentrations of glucose and plasma progesterone were determined. Total colostrum yield/10 h was greater (P = 0.002) in the SC does (1,102 ± 144 g) than in control does (405 ± 50 g). From 6 to 10 h postpartum, contents of colostrum protein and solids not fat were less (P ≤ 0.012) whereas lactose contents were greater (P = 0.035) in the SC does than in control does. Concentration of glucose in the blood at parturition was greater (P = 0.037) in the SC does (160 ± 13 mg/dL) than in control does (115 ± 12 mg/dL). A significant decrease (P = 0.001) in plasma progesterone concentrations occurred 1 d before parturition in control does, whereas the decrease (P = 0.008) occurred 3 d before parturition in SC does. For the second objective, 20 does (10 per group) and their single kids were randomly assigned to the same treatments as above for evaluation of dietary treatment on neonatal activity. Kid activity was assessed using videos recorded during the first 90 min after birth. Frequency of low-pitched bleats was greater (P < 0.001) in kids of SC does than in kids of controls. Frequencies and durations of teat seeking from 30 to 90 min after birth and of suckling activity were greater (P ≤ 0.015) in kids of SC does than in kids of controls. Duration of parturition was longer (P = 0.001) in control does (58 ± 10.2 min) than in SC does (21 ± 2.8 min). Finally, percentage of fetal malpresentation was greater (P = 0.036) in control does (33.3%) than in SC does (9.0%). We conclude that partial substitution of the grazing diet with a high-starch feed, corn, during the last 12 d of gestation improved colostrum yield and neonatal activity in goats grazing subtropical semi-arid rangeland.  相似文献   

7.
Pregnant ewes were chronically exposed to thermoneutral (TN; 20 degrees C, 30% relative humidity) or hot (H; 40 degrees C 9 h/d, 30 degrees C 15 h/d, 40% relative humidity) environments between d 64 and 136 to 141 of pregnancy. They were sampled for blood at 14-d intervals during this period for measurement of plasma metabolites and hormones, then slaughtered and dissected to measure conceptus weights, dimensions and fetal organ weights. Rectal temperatures of H ewes were elevated .3 to 1.0 C degrees above those of TN ewes throughout the experiment. Voluntary feed intakes were not altered by heat exposure except after 120 d of pregnancy, when feed intake was about 25% lower (P less than .10) by H than by TN ewes. Blood 3-hydroxybutyrate concentrations were not affected by heat, but plasma glucose concentrations were greater in H than in TN animals after 120 d (P less than .05). Placental weight, reduced by 54% (P less than .001) by heat exposure of ewes, was correlated positively with fetal weight and correlated negatively with fetal/placental weight ratio, fetal brain/liver weight ratio and fetal relative heart weight. Late in pregnancy, plasma concentrations of progesterone, cortisol and placental lactogen were reduced (P less than .01) in H ewes, whereas triiodothyronine levels were markedly lower (P less than .03) at all stages of pregnancy. Plasma concentrations of prolactin were elevated dramatically (P less than .01) and a modest increase (P less than .03) in somatotropin levels was recorded in H ewes. These results are consistent with our hypothesis that heat-induced fetal growth retardation is secondary to a primary reduction in placental growth; this could be mediated partly by reduced peripheral activity of thyroid hormones. Heat-induced reductions in secretion of progesterone and ovine placental lactogen more likely were a consequence than a cause of placental stunting.  相似文献   

8.
不同补饲方案对妊娠绒山羊冬春体况及胎儿发育的影响   总被引：2，自引：0，他引：2  
结合放牧,给妊娠70天的绒山羊补饲精料和粗料,可使其在冬末早春处于增重状态。随着补饲水平的提高,母羊增重、羔羊初生重及初生羔羊皮肤的总体毛囊密度、次级毛囊密度和次级毛囊数与初级毛囊数的比值(S/P)均有不同程度的提高,但初级毛囊密度并不受影响。母体较胎儿对改善营养更敏感,胎儿快速增重与次级毛囊生长同期进行。羔羊出生时绝大多数初级毛囊已进入活动状态,而次级毛囊尚未开始活动。初生羔羊较成年山羊具有较低的S/P值和较高的总体毛囊密度。  相似文献   

9.
不同糖蜜量对肉牛育肥效果的研究   总被引：1，自引：0，他引：1  
[目的]为了探讨肉牛育肥过程中的糖蜜用量。[方法]从120头西杂牛中随机选48头,分为8组,每组．6头。以四个处理2个重复进行试验;Tr1为对照组,饲喂全株玉米秸青贮加精料;Tr2-Tr1＋糖蜜1kg,Tr3-Tr1＋糖蜜2kg,Tr4-Tr1＋糖蜜3kg。试验期100d,其中预试期·10d,试验期90d。每30d称重1次,在上午空腹称重。本试验数据采用SAs软件进行统计分析。[结果]表明：添加甜蜜的各组与对照组比较,净增重均有显著性差异（P〈0．05）,Trl平均净增重为83．88kg,显著低于（P〈0．05）添加糖蜜的Tr2、Tr3和Tr4,各试验组中以Tr3添加糖蜜2kg,净增重效果最好,为119．83kg,显著高于试验各组;同样添加糖蜜的各组ADG与对照组比较差异显著（P〈0．05）,Trl为0．92kg,显著低于（P〈0．05）添加糖蜜的各组。[结论]表明添加2kg糖蜜的Tr3肉牛的增重效果好而经济,头均比Tr1增收入556．67元。  相似文献   

10.
The aim was to evaluate the influence of goat colostrum treated by heat on immune function in kids. Thirteen newborn kids were fed untreated colostrum (group A) and 13 kids were fed colostrum treated by heat (56 degrees C, 30 min) (group B). Blood samples were obtained at eight time points between the ages of 0 h to 28 days. Serum protein fractions, IgG levels and phagocytic activity of neutrophils were determined. A delayed type hypersensitivity (DTH) test was used, clinical status and body weight was recorded. There were no clinical signs of disease and no differences (P>0.05) on body weight between groups were noted. Kids from group B had less total protein levels and gamma-globulins than kids from group A (P<0.05). A decrease in serum IgG levels (P<0.05) was observed in kids from group B during all experiment. DTH response in kids from group B was lower (P<0.01) than group A, suggesting alteration on cellular immune system. No effects on phagocytic activity of the neutrophils were observed when both groups were compared (P>0.05). These results showed that colostrum treated by heat impaired some immunological parameters in kids, but these changes did not affect on clinical status or performance.  相似文献   

11.
Eight Hereford steers with an initial weight of 344 kg and a final weight of 476 kg were allotted randomly to two groups that were alternated between low (120 x maintenance) and high (2.27 x maintenance) intakes during five consecutive seasons in order to measure effects of season (cold stress) and intake on thermoneutral energy requirements. The steers were housed outdoors with neither shelter nor bedding and adapted to the specified intake levels for 21 to 31 d before each season's measurement of maintenance. Maintenance energy requirements were estimated as fasting heat production (FHP) and maintenance metabolized energy (MEm) by respiration calorimetry at thermoneutral temperatures. The high plane of nutrition caused a consistent increase of about 7% in FHP and 14% in MEm averaged across seasons (P less than .05). Within plane of nutrition, season had no effect on FHP or MEm, with the exception that values recorded in fall were lower than those recorded during the first summer (P less than .05). Nevertheless, daily gain during the winter acclimatization period was lower (P less than .05). We conclude that season had no effect on thermoneutral maintenance energy requirements (FHP, MEm) even though cold increased requirements for weight maintenance or gain. No interactions were found between season and plane of nutrition for the parameters measured. Acute cold stress, rather than chronically elevated metabolic rate, likely was responsible for poorer feedlot performance during the cold months of the year.  相似文献   

12.
Bucklings (n = 275) from a complete diallel of Boer, Kiko, and Spanish meat goats were slaughtered at 7 mo of age (4 mo postweaning) to evaluate genetic effects on carcass yield. Breed of sire did not affect (P > 0.05) live, carcass, and primal weights. Conversely, breed of dam was a consistently significant source of variation for carcass weight traits. Kiko dams produced kids with heavier (P < 0.05) live, carcass, and primal weights than Boer dams. Weights from Spanish dams were intermediate to Boer and Kiko with the significance of differences varying by trait. Cold carcass dressing percent was affected (P < 0.01) by breeds of sire and dam. Boer sires decreased (P < 0.05) dressing percent compared with Kiko and Spanish sires. Dressing percent was also less (P < 0.01) from Boer dams than from Kiko dams; Spanish dams were intermediate and did not differ (P > 0.05) from Boer or Kiko. Subjective conformation scores for muscularity were affected (P < 0.01) by breeds of sire and dam. Boer-sired kids had better (P < 0.01) live scores than Kiko-sired kids. Progeny of Boer dams had better (P < 0.05) live scores than progeny of Spanish dams. Boer-sired kids also had better carcass scores (P < 0.05) than Kiko-sired and Spanish-sired kids. Breed differences for primal cut proportions were negligible. Proportional boneless meat yields did not vary (P > 0.05) by breeds of sire or dam. Direct effects of Boer were negative for carcass weight, dressing percent, and shoulder weight and positive for proportional leg weight. Direct effects of Kiko were positive for carcass weight and shoulder weight and negative for proportional leg weight. Direct effects of Spanish did not differ (P > 0.10) from 0 for any trait tested. Heterosis levels were similar among breed pairings. Heterosis was substantial (P ≤ 0.05) for live, carcass, and primal weights (5 to 9%) but not for dressing percent, proportional boneless meat yield, or primal weight proportions (<2%). Significant genetic variation was observed among goat breeds for carcass yield traits. Dam breed was more influential than sire breed. Boer germplasm was not superior to Kiko or Spanish germplasm for carcass yield when semi-intensively managed on humid, subtropical pasture. Results emphasize the importance of comparative breed evaluations to provide industry with reliable information on carcass yield among goat genotypes.  相似文献   

13.
Oral administration of sulphadoxine to adult goats (100 mg/kg body weight) resulted in absorption of about two thirds from the gastrointestinal tract. The absorption rate was lowest in newborn kids and increased with increasing age. Following administration of sulphadoxine (40 mg/kg body weight) through a rumen fistula about 80% was absorbed in cows. Also the elimination rate for sulphadoxine was lower in newborn kids than in adult goats and increased with the age. Oral administration of the trimethorpim (TMP) to kids, goats (20 mg/kg body weight) and cows (8 mg/kg body weight) resulted in higher plasma concentrations in newborn kids than in the older age groups and the maximal concentration of TMP in the blood of adult goats and cows was lower than 0.2 μg/ml. In vitro experiments showed that trimethoprim may be degraded by ruminal microorganisms, but from experiments with oral administration of trimethoprim to cows it is concluded that metabolism in the cow's liver is at least as important as ruminal degradation.  相似文献   

14.
The effects of ionophores on liver weight and function were determined in finishing steers (n = 24; avg weight 440 kg). Steers were group-fed one of three treatments (control, lasalocid or monensin at 33 mg/kg feed) for 46 d prior to slaughter. Three days prior to slaughter, blood was collected for the determination of serum Ca and Mg. At slaughter, the liver was removed, weighed, sampled, frozen in liquid nitrogen and subsequently analyzed for concentrations of carbohydrate metabolites and minerals. Liver weight (5.9 kg) was unaffected by treatment. Serum and hepatic Ca and Mg were not affected by ionophore treatment. Hepatic glycogen levels in steers fed ionophores were unaffected by treatment. Fructose 1,6-bisphosphate was 21% lower (P less than .10) in hepatic tissue of steers fed ionophores, whereas dihydroxyacetone phosphate was 15 to 37% greater in hepatic tissue of steers fed monensin (P less than .20) or lasalocid (P less than .10). Glyceraldehyde 3-phosphate was elevated more extensively by lasalocid than by monensin with increases of 72 (P less than .05) and 132% (P less than .001), respectively, over controls. Glycerol 3-phosphate levels were 37% (P less than .05) and 12% (NS) greater with these ionophores. Hepatic levels of pyruvate were elevated 12 (NS) to 36% (P less than .17) for monensin and lasalocid. Fructose 2,6-bisphosphate levels were 25% lower (P less than .25) in hepatic tissue of steers fed ionophores than in hepatic tissue from control steers. Other metabolites of carbohydrate metabolism in hepatic tissue were not altered appreciably. Changes in levels of intermediary metabolites of carbohydrate metabolism suggest alterations in hepatic carbohydrate metabolism favoring gluconeogenesis in steers fed ionophores.  相似文献   

15.
Seeds of the tall fescue ( Festuca arundinacea Schreb .) cultivars Kentucky 31 and an experimental ryegrass X tall fescue hybrid derivative strain (G1-307), and orchard grass (OG) seed were fed in a carrier diet to calves in controlled environmental rooms (31 to 32 C). Both tall fescue varieties produced symptoms of summer toxicosis in dairy steers. Total feed intake (P less than .01) and water intake (P less than .01) of calves were reduced by the tall fescue seed diets when compared with orchard grass. Steers fed G1-307 and Kentucky 31 tall fescue lost (NS) 17.5 and 7.8 kg of body weight, respectively, while those consuming orchard grass gained (P less than .01) 6.2 kg during the experiment. Rectal temperatures were lower (P less than .05) in the calves fed OG (39.4 C) when compared with those fed G1-307 (40.6 C) and Kentucky 31 (40.8 C) tall fescue seed, respectively. In a second trial Kentucky 31 seed was fed in a carrier diet to Holstein steers at graded levels of 0, 350, 700 and 1,050 g seed/d. Consumption of 700 and 1,050 g seed/d adversely affected performance of steers. Total feed intake was lower and water intake was reduced (P less than .05), with rectal temperatures being elevated (P less than .01) in these two groups when compared with 0- or 350-g treatments. No significant differences were detected in body weight changes in this trial. Respiration rates were not significantly affected in either trial. Results of these trials with the young bovine indicate that a toxic substance(s) is present in tall fescue seed.  相似文献   

16.
The objective of this study was to evaluate effects of the condensed tannin (CT)-containing forage sericea lespedeza (sericea lespedeza (SL); Lespedeza cuneata; 15.2% CT), on fecal egg count (FEC), larval development (larvae/10 g of feces), worm burden and immune response compared with a crabgrass (Digitaria ischaemum)/Kentucky 31 tall fescue (Festuca arundinacea; control forage (CTF)) forage low in CT (0.32% CT) in grazing Angora does and their kids. Fifty worm-free mixed-age does were randomly allocated to three treatments. One treatment (10 does; initial liveweight (LW) = 45+/-1.5 kg) entailed grazing of SL forage from April 25 to July 15, 2002 with a second treatment of CTF (20 does; initial LW = 43+/-1.4 kg) grazing during the same period. Does of the third treatment (20 does; initial LW = 44+/-1.4 kg) grazed a sward of SL for 2 weeks and then one of CTF for 2 weeks followed by alternating between the two pastures every 2-week rotational grazing (ROT). To gauge levels of infective larvae on pasture, three worm-free Angora kids (initial LW = 3.6+/-0.2 kg) were randomly selected as tracers. Tracers grazed for final 60 days and were euthanized for determination of worm burden. The immune response of does was measured by skin thickness reaction after the intradermal injection of 250 microg phytohemagglutinin (PHA). Mean FEC for SL and ROT were substantially lower (P < 0.01) than for CTF does (145, 329 and 894 eggs/g, respectively). The FEC for kids was lower (P < 0.05) for SL than for ROT and CTF (550, 2757 and 3600 eggs/g, respectively). Total fecal egg output (3.3, 6.0 and 26.9 x 10(5) eggs/day, respectively) and larval development (242, 263 and 792 larvae/10 g, respectively) were lower (P < 0.05) for SL and ROT than for CTF. Tracers grazing on SL had lower total worm burdens than ROT and CTF (P < 0.01). The immune response was higher (P < 0.01) for SL (4.9 mm) and ROT (6.0 mm) than for CTF (3.0 mm) at 12 h after injection of PHA. The packed cell volume (PCV) in does was higher (P < 0.01) for SL and ROT than for CTF (27, 26 and 23%, respectively). Does that grazed CT-containing forage had considerably lower milk somatic cell counts (SCC) than does grazing non-CT-containing forage. In summary, grazing CT forages reduced FEC, larval development and worm burden, and also appeared to enhance immune response. The CT-containing forage SL reduced gastro-intestinal parasite infections of Angora does and kids.  相似文献   

17.
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   

18.
Housing temperature effects on growth, feed utilization and feed digestion of 12, 7-mo-old Standardbred colts were evaluated for 22 wk beginning in late November. Colts were assigned to one of two treatments: housed in a barn heated at 10 degrees C (warm) or housed in a barn with no external heat supply (cold). All horses were allowed outdoors for 4 h daily. Mean temperatures of the warm and cold barn from November to April were 10.9 +/- .66 and -5.2 +/- 1.72 degrees C, respectively. Hair coat weight of cold-housed colts was 1.4- to twofold (P less than .05) that of warm-housed colts from December through April but declined for both groups from fall to spring. All colts were fed a pelleted diet to meet National Research Council (1989) energy guidelines for moderate gain (.65 kg/d). Warm-housed colts gained weight 29% more rapidly (P less than .01) than cold-housed colts (.67 vs .52 kg/d). Skeletal growth, measured by cannon bone circumference, wither and croup height, was not affected by housing temperature. Nutrient digestion by both groups of colts was compared to that of mature, warm-housed ponies. Ponies had longer (P less than .05) digestive tract retention times and higher digestibilities for every nutrient than the young horses did. Although retention times by all colts were similar, cold-housed colts digested more ADF and less phosphorus (P) than did warm-housed colts (P less than .05). Over time, digestibilities of DM, NDF and P declined (P less than .05) for colts but not for ponies. Maintenance energy needs were estimated at 34.6 kcal/kg BW for cold-housed colts vs 26.3 kcal/kg BW for warm-housed colts. Young horses need 1.3% more maintenance energy per Celsius degree decrease in temperature below 0 degree C. To sustain a constant moderate gain, daily DE intake needs to be increased .7% per Celsius degree decrease in ambient temperature below 0 degree C.  相似文献   

19.
Morphometric, metabolic, and behavioral modifications were studied in goat kids after maternal feed restriction during the last one-third of pregnancy. At birth, only kids from twin and triplet litters were studied [n=40 kids born to control dams (CONT) and n=38 born to restricted dams (REST)] and only males thereafter (n=13 CONT and 15 REST kids) until slaughter at 6 wk of age. Kids born to restricted goats had a smaller abdominal girth at birth (P<0.01) and tended to have a smaller body mass index (P=0.10) and a smaller density index (P=0.09) than kids born to CONT goats. Male REST kids had a lighter birth weight (P=0.03) than male CONT kids, but no differences (all P>0.10) were found for BW and morphometric measurements thereafter. Decreased NEFA concentrations suggested that male REST kids mobilized their body reserves less than CONT kids at birth (P<0.01). No modifications in drinking tests at 3 and 5 wk of age were observed, or in feeding behavior and emotional reactivity at 5 wk of age (all P>0.10). In conclusion, maternal feed restriction in the last one-third of pregnancy resulted in a decrease in birth size, but male kids rapidly caught up, and there were no changes in behavior, morphology, or metabolism during rearing.  相似文献   

20.
The influence of supplemental phenothiazine (P) on growth and physiological criteria was studied in parasite-controlled calves consuming endophyte (Acremonium coenophialum)-infected tall fescue (TF). In Exp. 1, nine Angus heifer calves (312 kg) were supplemented with 227 g corn-mineral (CM) mix twice daily and allowed ad libitum access to either high-endophyte (HE) G1-307 (greater than 90% infected) or low-endophyte (LE) Kenhy (less than 1% infected) tall fescue hay, or HE G1-307 plus 2 g/d P in the daily supplement. Calves were kept in temperature-controlled rooms for 12 d at 21 degrees C followed by 7 d at 34 degrees C. In Exp. 2, 48 Angus steer calves (312 kg) were assigned to treatment groups consisting of calves grazing HE Kentucky-31 (57% infected) or LE Johnstone (less than 1% infected) TF, and supplemented daily with either .91 kg of a control CM mix or .91 kg of the CM mix containing 2 g P. The 112-d experiment was initiated on May 4 with BW and rectal temperature (RT) measurements and blood collected at 28-d intervals. In both experiments, calves receiving HE TF had lower (P less than .01) serum prolactin concentrations (PRL) at elevated ambient temperature and lower (P less than .01) serum alkaline phosphatase activities (AP) but higher (P less than .01) RT than calves consuming LE TF regardless of ambient temperature.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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