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1.
SUMMARY Twenty-five Thoroughbred (TB) and 25 Standardbred (SB) stables were visited to determine their feeding practices. The ingredients of the main feed of the day for a mature gelding of average size in full training were weighed at each stable. Nutrient content of diets was calculated using published data for the individual ingredients. Results are expressed as mean±sd. The estimated body weight of TB horses was 493±34 kg and 437±32 kg for SB horses. There was considerable variation in diet composition and nutrient intake between stables. The TB trainers fed 11.0±2.4 kg and SB trainers 11.8±2.5 kg per day. The concentrate component of the diet weighed 7.8±1.6 and 7.7±2.3 kg for TB and SB stables, respectively, and the roughage component for TB horses 3.3±1.4 and SB horses 4.1±1.4 kg per day. The digestible energy intake of horses at TB stables was 129±29 MJ per day and at SB stables 132±31 MJ per day. Crude protein intake of TB horses was 1452±363 g and SB horses 1442±338 g per day. There were differences in some feeding practices at TB and SB stables. Standardbred trainers fed more roughage than TB trainers. Standardbred trainers fed chaffed lucerne (alfalfa) and cereal hays as the major roughage, whereas TB trainers fed more hay. The major hay type fed by TB trainers was lucerne, whereas many SB trainers preferred clover hay. Both trainers fed oats as the major grain, but TB trainers fed slightly more maize (corn) than SB trainers. The SB trainers fed barley as part of the concentrate component of the diet, whereas TB trainers usually fed boiled barley and linseed oil in winter only. Although many trainers used vitamin and mineral supplements, this appeared unnecessary in many Instances, especially with respect to Iron. Calcium and NaCI supplementation was necessary for some diets. We concluded that while there was a wide range in feed intake and diet composition for both TB and SB horses, average nutrient intakes were similar to National Research Council (1989) recommendations for horses performing intense work.  相似文献   
2.
An experiment was conducted to determine the effect of dietary betaine (0, 0.125, 0.250, or 0.500%) on growth, carcass traits, pork quality, plasma metabolites, and tissue betaine concentrations of cross-bred finishing pigs. Four replications of three pigs (two barrows and one gilt) each were used for each treatment. The basal diet contained 0.85 (69 to 88 kg BW) or 0.65% Lys (88 to 115 kg BW). Overall ADG and gain:feed were not affected (P > 0.10) by betaine, but overall ADFI was decreased (quadratic, P < 0.05; 0 vs betaine, P < 0.01) by betaine; pigs fed 0.250% betaine had the lowest ADFI. Loin muscle area, average back-fat, dressing percentage, percentage lean, total fat, lean:fat, and leaf fat weight were not affected (P > 0.10) by betaine. Tenth-rib backfat thickness was decreased (quadratic, P < 0.05; 0 vs betaine, P < 0.05); pigs fed 0.250% betaine had the lowest 10th-rib backfat thickness. Carcass length was increased (linear, P < 0.05; 0 vs betaine, P < 0.10) as the level of betaine was increased. Fat-free lean, lean gain per day, ham weight, ham fat-free lean, and ham percentage lean were increased (quadratic, P < 0.10), but percentage fat, total ham fat, percentage ham fat, and butt-fat thickness were decreased (quadratic, P < 0.10); these traits were respectively highest or lowest in pigs fed 0.250% betaine. Thaw loss and 24-h pH were increased (quadratic, P < 0.10; 0 vs betaine, P < 0.05) and cook loss was decreased (linear, P < 0.05) in pigs fed betaine. The CIE L* value for the biceps femoris was decreased (quadratic, P < 0.10; 0 vs betaine, P < 0.10); pigs fed 0.250% betaine had the lowest CIE L* value. Subjective color, firmness-wetness, marbling, percentage moisture and bound water of the loin muscle, and shear force were not affected (P > 0.10) by betaine. Betaine was not detectable (< 0.07 mg/g) in the loin muscle of pigs fed 0% betaine, but betaine was detectable and relatively constant in pigs fed 0.125, 0.250, or 0.500% betaine (0.22, 0.17, and 0.21 mg/g, respectively). Plasma urea N, total protein, albumin, triglycerides, and HDL cholesterol concentrations were not affected (P > 0.10). Plasma total cholesterol (linear, P < 0.10) and NEFA (quadratic, P < 0.10) were increased in pigs fed betaine. Betaine improved carcass traits when provided at 0.250% of the diet and improved some aspects of pork quality.  相似文献   
3.
Two experiments were conducted to determine the effects of dietary Cr tripicolinate (CrPic) or Cr propionate (CrProp) on growth, carcass traits, plasma metabolites, glucose tolerance, and insulin sensitivity in pigs. In Exp. 1, 36 barrows (12 per treatment; initial and final BW were 20 and 38 kg) were allotted to the following treatments: 1) corn-soybean meal basal diet (control), 2) as 1 + 200 ppb Cr as CrPic, or 3) as 1 + 200 ppb Cr as CrProp. Growth performance data were collected for 28 d, and then 23 pigs (seven, eight, and eight pigs for treatments 1, 2, and 3, respectively) were fitted with jugular catheters and a glucose tolerance test (500 mg glucose/kg BW) and an insulin challenge test (0.1 IU of porcine insulin/kg BW) were conducted. Both CrPic and CrProp decreased (P < 0.05) ADG and ADFI but did not affect gain:feed (P > 0.10). Fasting plasma glucose, total cholesterol, urea N, insulin, and high-density lipoprotein cholesterol:total cholesterol concentrations were not affected (P > 0.10) by either Cr source. Pigs fed CrPic had lower (P < 0.02) fasting plasma NEFA concentrations than control pigs, but plasma NEFA concentrations of pigs fed CrProp were not affected (P > 0.10). During the glucose tolerance test, glucose and insulin kinetics were not affected by treatment (P > 0.10). During the insulin challenge test, glucose clearance was increased (P < 0.01) in pigs fed CrProp but not affected (P > 0.10) in pigs fed CrPic. Glucose half-life was decreased (P < 0.03) in pigs fed CrPic or CrProp, but insulin kinetics were not affected (P > 0.10). In Exp. 2, 48 barrows (four replicates of four pigs per replicate; initial and final BW were 23 and 115 kg) were allotted to the same dietary treatments in a growing-finishing study. Average daily gain, ADFI, and gain:feed were not affected (P > 0.10) by treatments. Carcass length tended (P = 0.10) to be greater in pigs fed CrPic than in pigs fed CrProp, but other carcass measurements were not affected (P > 0.10). Glucose kinetics from the insulin challenge test indicate that both CrPic and CrProp increase insulin sensitivity and that both Cr sources are bioavailable.  相似文献   
4.
Effect of mannan oligosaccharides on growth performance of weanling pigs   总被引:8,自引:0,他引:8  
Four experiments were conducted to evaluate the effects of mannan oligosaccharides (provided by Bio-Mos [BM], a product containing a minimum of 28% glucomannoprotein from S. cerevisiae) on growth performance of nursery pigs. Treatments were replicated with five to six pens of four to five pigs each. Initial BW ranged from 4.7 to 5.4 kg, and pigs were weaned at 16 to 20 d of age. Experiments 1, 2, and 4 consisted of Phase 1 (7 to 8 d), Phase 2 (12 to 14 d), and Phase 3 (7 to 8 d) periods, but Exp. 3 consisted only of Phase 1 (7 d) and 2 (14 d) periods. The diets for Phase 1, 2, and 3 contained 1.6, 1.5, and 1.1% Lys, respectively. The treatments in Exp. 1 were 0, 0.20, and 0.30% BM, which did not affect growth performance. The treatments in Exp. 2 were two levels of excess Zn (0 and 3,000 ppm) and three levels of BM (0, 0.20, and 0.30%) in a 2 x 3 factorial. Excess Zn increased (P < 0.08) ADG and ADFI in Phase 2 and 3 and overall. The 0.20% BM addition increased ADG (Phase 3 and overall) and ADFI (Phase 2 and overall) in the absence of excess Zn but did not affect or decreased these response variables in the presence of excess Zn (Zn x BM quadratic, P < 0.08). Experiment 3 was similar to Exp. 2, but the 0.30% BM addition was not used. Excess Zn decreased (P < 0.09) ADG in Phase 1 but increased (P < 0.09) ADG and ADFI in Phase 2. The BM decreased (P < 0.03) overall ADFI but increased Phase 2 and overall ADG and gain:feed (GF) in the absence of excess Zn but not in the presence of excess Zn (Zn x BM, P < 0.07). The BM decreased ADFI during Phase 2, but the decrease was greater in pigs fed excess Zn (Zn x BM, P < 0.07). Experiment 4 evaluated the interactive effects of the antibiotic (oxytetracycline and neomycin) and BM and of Zn and BM. Antibiotic (no excess Zn) increased (P < 0.01) ADG and ADFI in Phases 2 and 3 and overall. The BM addition decreased ADG and GF in Phase 2 when the antibiotic was not in the diet but increased ADG when the antibiotic was in the diet (antibiotic x BM, P < 0.05). Excess Zn increased (P < 0.07) ADG and ADFI during Phases 2 and 3 and overall. In Phase 2, the 0.20% BM decreased GF when excess Zn was not added to the diet but increased GF when Zn was included (Zn x BM, P < 0.03). Mannan oligosaccharides improved pig performance in some instances during Phase 2 when fed in combination with an antibiotic and no excess dietary Zn, but it had no effect or negative effects in the presence of excess Zn or in the absence of an antibiotic.  相似文献   
5.
Two experiments were conducted to determine the effect of substituting a more available dietary carbohydrate (CHO) for portions of corn or fat in the diet on growth performance, carcass traits, meat quality, and serum or plasma metabolites in growing-finishing pigs. A three-phase feeding program was used with corn-soybean meal diets formulated to provide 105% of the Lys requirement for barrows or gilts gaining 325 g of lean daily in Exp. 1 or gilts gaining 350 g of lean daily in Exp. 2. Diets were isoenergetic within experiments. All other nutrients met or exceeded suggested requirements. In Exp. 1, pigs were allotted to three dietary treatments (0, 7.5, or 15.0% sucrose), with three replications of barrows and three replications of gilts, and with three or four pigs per replicate pen; average initial and final BW were 25.2 and 106.7 kg. In Exp. 2, gilts were allotted to two dietary treatments (waxy [high amylopectin] or nonwaxy [75% amylopectin and 25% amylose] corn as the grain source), with five replications of four gilts per replicate pen; average initial and final BW were 37.7 and 100.0 kg. In Exp. 1, ADG and gain:feed ratio increased linearly (P < 0.02) as dietary sucrose increased. Minolta color scores, a* and b*, and drip loss (P < 0.06) also increased linearly with added sucrose. In Exp. 2, ADG, carcass weight and length, and the Minolta a* value were greater for pigs fed waxy corn (P < 0.08) than for those fed nonwaxy corn. Feed intake, longissimus muscle area, 10th-rib and average backfat thickness, dressing percentage, fat-free lean, percentage of lean and muscling, lean gain per day, total fat, percentage fat, lean:fat ratio, serum or plasma metabolites (Exp. 1: serum urea N; Exp. 2: serum urea N, and plasma nonesterified fatty acids, triacylglycerols, total and high-density lipoprotein cholesterol, insulin, and total protein), pH of the longissimus muscle, and subjective muscle scores (color, firmness-wetness, and marbling) were not affected by diet in either experiment. In summary, increasing availability of dietary CHO in growing-finishing pig diets improved growth performance, but it did not affect carcass traits.  相似文献   
6.
A cooperative research study involving 635 gilts was conducted at eight research stations to further estimate the lysine requirement of finishing gilts. Dietary crude protein levels of the five dietary treatments ranged from 16.0 to 24.4% with calculated lysine levels of .80, .95, 1.10, 1.25, or 1.40%. Each station contributed a minimum of two replicate pens of pigs per treatment. Average initial and final weights were 53.6 and 116.4 kg, respectively. At the end of the experimental period, pigs were killed and hot carcass weight, 10th-rib fat depth, and longissimus muscle area were measured. Carcass fat-free lean percentage and fat-free lean gain were estimated from these data. Daily lysine intakes averaged 21.8, 25.9, 30.5, 34.3, and 37.8 g/d for the five treatment groups, respectively. Increasing the dietary lysine from .80 to .95% numerically increased weight gain and gain:feed, but these increases were not maintained at higher levels of dietary lysine. Overall, rate and efficiency of gain decreased (cubic, P < .01) with increasing dietary lysine. Carcasses were leaner at the two higher levels of dietary lysine as evidenced by reduced 10th rib backfat (linear, P < .01), increased longissimus area (quadratic, P < .04), and increased percentage of estimated fat-free lean (linear, P < .01). Carcass fat-free lean gain was not influenced by dietary lysine except for a small numerical improvement (P < .11) at the .95% level of dietary lysine that paralleled the improvement in body weight gain. The results indicate that the dietary lysine requirement of finishing gilts with a mean carcass fat-free lean growth rate of 306 g/d from 54 to 116 kg body weight is probably no higher than .80% of the diet to achieve maximum rate and efficiency of body weight gain and carcass lean growth rate. The results also indicate that higher dietary lysine levels may increase carcass leanness in finishing gilts, possibly due to reduced intake of NE. Whether this response is due to the effects of lysine alone, protein (i.e., other amino acids), or soybean meal is unknown.  相似文献   
7.
本论文研究了饲料加工的两个关键参数(调质温度和时间)对育肥猪颗粒饲料淀粉糊化度和维生素沉积的影响。日粮配方为含30%干酒糟及其可溶物的玉米-豆粕型基础日粮。整个试验中配方保持不变。本试验采用2×3双因子设计,调质温度分别为77℃和88℃,调质时间分别15秒、30秒和60秒。此外,本试验还设置一个对照组,对照组饲料不采用调质制粒工艺,而是采用粉料饲喂。因此,本试验共有7个处理组。采集调质后制粒前(热干粉)、制粒后冷却前(热制粒)、以及制粒冷却后(冷制粒)的样品,并分析这三种样品的总淀粉率、淀粉糊化  相似文献   
8.
[目的]明确高良姜叶枯病病原菌.[方法]病原菌从高良姜感病组织上分离并依据柯赫氏法则进行致病性测定,病原菌的鉴定主要通过形态鉴定和ITS序列分析.[结果]高良姜叶枯病病原菌确定为可可毛色二孢(Lasiodiplodia theobromae),属子囊菌门(Ascomycota),座囊菌纲(Dothideomycetes),葡萄座腔菌目(Botryosphaeriales),葡萄座腔菌科(Botryosphaeriaceae),毛色二孢属(Lasiodiplodia).[结论]首次报道高良姜叶枯病病原菌为可可毛色二孢.  相似文献   
9.
10.
分析了高温胁迫条件下豇豆[Vigna unguiculata(L.)Walpers]幼苗叶片细胞膜透性和保护酶活性等理化指标的变化及品种间的差异,分析了高温胁迫对豇豆叶片蛋白质表达的影响.结果显示,在高温胁迫下,8个豇豆品种的热害指数差异有统计学意义,直观表现为之豇28-2和白籽豇豆耐热性强,而高产四号、宁豇三号和红豇豆的耐热性差;所有豇豆品种的细胞膜透性和丙二醛(MDA)质量摩尔浓度均有不同程度的增大,但耐热性强的品种增幅较小;超氧化物歧化酶(SOD),过氧化物酶(POD)和过氧化氢酶(CAT)活性呈现出先上升后下降的变化趋势,而耐热性强的品种增幅较大;耐热豇豆品种的可溶性糖浓度及高温胁迫后的增值均低于耐热性较差的品种;双向电泳结果表明,高温胁迫特异性诱导了15种和抑制了6种蛋白质表达,另鉴别到8种上调和10种下调表达蛋白.表明高温胁迫引起一系列生理生化和基因表达的变化.该研究为今后解析豇豆的耐热机理、选育耐热品种和发掘重要抗热基因等奠定了基础.  相似文献   
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