Effects of blend of canola oil and palm oil on nutrient intake and digestibility,growth performance,rumen fermentation and fatty acids in goats

The study examined the effects of blend of 80% canola oil and 20% palm oil (BCPO) on nutrient intake and digestibility, growth performance, rumen fermentation and fatty acids (FA) in goats. Twenty‐four Boer bucks were randomly assigned to diets containing 0, 4 and 8% BCPO on a dry matter basis, fed for 100 days and slaughtered. Diet did not affect feed efficiency, growth performance, intake and digestibility of all nutrients except ether extract. Intakes and digestibilities of ether extract, unsaturated fatty acids (FA) and total FA were higher (P < 0.05) while digestibility of C18:0 was lower (P < 0.05) in oil‐fed goats than the control goats. Total volatile FA, acetate, butyrate, acetate/propionate ratio and methane decreased (P < 0.05) with increasing BCPO but propionate, NH₃‐N and rumen pH did not differ between diets. Ruminal concentration of C18:0, n‐3 FA and total FA increased (P < 0.05) while C12:0, C14:0, C15:0 and n‐6 FA decreased with increasing BCPO. Analysis of the FA composition of Triceps brachii muscle showed that concentrations of C16:0, C14:0 and C18:2n‐6 were lower (P < 0.05) while C18:1n‐9, C18:3n‐3 and C20:5n‐3 were higher in oil‐fed goats compared with control goats. Dietary BCPO altered muscle lipids without having detrimental effects on nutrient intake and digestibility and growth performance in goats.     

Effects of ruminal infusion of volatile fatty acids on plasma concentration of growth hormone and insulin in sheep.

In an initial experiment we observed postprandial changes in plasma concentrations of growth hormone (GH), insulin, glucagon, and somatostatin (SRIF) in sheep. We then examined whether increasing the rumen concentration of volatile fatty acids (VFA) by infusing a VFA mixture at three rates (53.5, 107, and 214 micromol/kg/min for 4 hr) mimicked the postprandial changes in hormone secretion. Feeding significantly (P < 0.05) suppressed the plasma GH concentration for 6 hr, whereas it significantly (P < 0.05) increased plasma concentrations of insulin, glucagon, and SRIF. Plasma glucose levels tended to decrease after feeding but then gradually increased over the prefeeding level (P < 0.05). Intraruminal infusion of the VFA mixture at 107 micromol/kg/min caused similar changes in ruminal VFA concentrations to those seen after feeding. The infusion significantly (P < 0.05) suppressed GH secretion in a dose-dependent manner, whereas it caused a significant (P < 0.05) increase in insulin and glucose concentrations without changing glucagon concentrations. From these results, we conclude that the postprandial change in ruminal VFA concentration may be a physiological signal which modifies GH and insulin secretion in sheep.     

稻草不同处理方法对山羊增重的试验研究

试验研究了稻草经氨化、微贮等处理后对山羊增重的影响。结果表明:与物理处理法(切短)相比,经氨化、微贮处理后的稻草对山羊的适口性较好,日增重显著提高,其中氨化组和微贮组的平均日增重分别比对照组提高34.97%(P<0.05)和63.25%(P<0.01);稻草经过氨化、微贮处理后饲喂山羊,饲料转化率有所提高,并能取得较好的经济效益,有推广应用价值。     

不同饲养方式对牦犊牛生长性能的影响

试验旨在研究不同饲养方式对牦犊牛生长性能的影响.选取刚出生的甘南犊牦牛45头,按试验要求随机分为3组,每组设3个重复,每个重复5头,分别采用6月龄断奶补饲(试验Ⅰ组)、全哺乳(试验Ⅱ组)和半哺乳(对照组即传统饲养方式)3种饲养方式,均采用自由放牧,饲养时间为18个月.结果表明,早期断奶补饲会明显增加犊牦牛的体重,在18月龄时,3组犊牛体重差异极显著(P<0.01);体斜长、体高、胸围变化上差异显著(P<0.05);在管围变化上,两试验组之间差异不显著(P>0.05),试验组与对照组之间差异显著(P<0.05).结果提示,对牦犊牛采用适时断奶补饲方式优于全哺乳和传统饲养方式;在冷季,对甘南犊牦牛的短期育肥应集中在5～7个月.     

Effects of urea plus nitrate pretreated rice straw and corn oil supplementation on fiber digestibility,nitrogen balance,rumen fermentation,microbiota and methane emissions in goats

Background: Urea pretreatment is an efficient strategy to improve fiber digestibility of low quality roughages for ruminants. Nitrate and oil are usually used to inhibit enteric methane(CH_4) emissions from ruminants. The objective of this study was to examine the combined effects of urea plus nitrate pretreated rice straw and corn oil supplementation to the diet on nutrient digestibility, nitrogen(N) balance, CH_4 emissions, ruminal fermentation characteristics and microbiota in goats. Nine female goats were used in a triple 3 × 3 Latin Square design(27 d periods). The treatments were: control(untreated rice straw, no added corn oil), rice straw pretreated with urea and nitrate(34 and 4.7 g/kg of rice straw on a dry matter [DM] basis, respectively, UN), and UN diet supplemented with corn oil(15 g/kg soybean and15 g/kg corn were replaced by 30 g/kg corn oil, DM basis, UNCO).Results: Compared with control, UN increased neutral detergent fiber(NDF) digestibility(P 0.001) and copies of protozoa(P 0.001) and R. albus(P 0.05) in the rumen, but decreased N retention(-21.2%, P 0.001), dissolved hydrogen concentration(-22.8%, P 0.001), molar proportion of butyrate(-18.2%, P 0.05),(acetate + butyrate) to propionate ratio(P 0.05) and enteric CH_4 emissions(-10.2%, P 0.05). In comparison with UN, UNCO increased N retention(+34.9%, P 0.001) and decreased copies of protozoa(P 0.001) and methanogens(P 0.001). Compared with control, UNCO increased NDF digestibility(+8.3%, P 0.001), reduced ruminal dissolved CH_4 concentration(-24.4%, P 0.001) and enteric CH_4 emissions(-12.6%, P 0.05).Conclusions: A combination of rice straw pretreated with urea plus nitrate and corn oil supplementation of the diet improved fiber digestibility and lowered enteric CH_4 emissions without negative effects on N retention. These strategies improved the utilization of rice straw by goats.     

利用体外法研究不同水平苜蓿皂苷对山羊瘤胃内pH值和挥发性脂肪酸的影响

试验通过体外培养法研究日粮中添加苜蓿皂苷对山羊瘤胃微生物发酵功能的影响。试验分5组,各组苜蓿皂苷的添加水平分别为基础底物(2g)的0(对照组)、1%、2%、3%及4%,每组3个重复,体外厌氧培养24h,并分别测定各处理组pH值和挥发性脂肪酸含量。结果表明:添加苜蓿皂苷未对培养液pH值产生显著影响;添加1%～4%的苜蓿皂苷可极显著提高培养液中乙酸、丙酸浓度(P<0.01);添加1%的苜蓿皂苷可极显著提高丁酸浓度(P<0.01),2%组可显著提高丁酸浓度(P<0.05);各苜蓿皂苷添加组中乙酸/丙酸的比例均极显著低于对照组(P<0.01)。结论:本试验条件下,添加1%～4%的苜蓿皂苷可改善瘤胃发酵模式,提高反刍动物对发酵终产物的利用率,且添加1%的苜蓿皂苷效果最佳。     

补饲马铃薯藤对山羊生长性能、消化率和胴体特征的影响

本研究旨在探讨马铃薯藤饲喂水平对山羊生长性能、养分消化率和胴体特征的影响.试验将平均初始体重为(14.42±0.24)kg的40头山羊随机分为4组,每组5个重复,每个重复2头.T1组仅饲喂干草,T2组饲喂干草+100％马铃薯藤,T3组饲喂干草+50％马铃薯藤+50％浓缩料,T4组饲喂100％浓缩料.在为期10周的饲养试...     

不同酶制剂对水稻秸秆青贮营养品质和饲喂价值的影响

试验旨在探讨纤维素酶、木聚糖酶和青黄贮酶对水稻秸秆青贮品质的影响。以水稻秸秆为原料,设置4个处理,分别为CK(对照)、XYL(添加0.5%木聚糖酶)、CEL(添加0.5%纤维素酶)和CAS(添加0.5%青黄贮酶),每个处理6次重复,室温下青贮120 d后,进行感官评定,并取样测定营养品质和养分消化率,计算其饲喂价值。结果表明:(1)XYL,CEL和CAS处理的pH显著低于CK(P<0.05),色泽评分、质地评分、水分评分和pH评分均显著高于CK(P<0.05),感官评定等级均为良好;(2)XYL,CEL和CAS处理的DM、K、Ca、Mg含量均显著高于CK(P<0.05),ADF、NDF含量均显著低于CK(P<0.05),且CAS的NFC含量显著高于CK(P<0.05);(3)XYL,CEL和CAS处理的NDFD30、NDFD48、IVTDMD30和IVTDMD48均显著高于CK(P<0.05),且XYL和CAS处理的dNDF30、dNDF48均显著高于CK(P<0.05);(4)XYL,CEL和CAS处理的TDN、DDM、DMI、RFV和RFQ均显著高于CK(P<0.05),且CAS的TDN、DDM、DMI、RFV和RFQ均显著高于XYL和CEL处理(P<0.05)。说明水稻秸秆青贮中,添加木聚糖酶、纤维素酶和青黄贮酶,均能改善其感官品质和营养品质,提高养分消化率和饲喂价值;综合各项指标分析,青黄贮酶的添加效果优于木聚糖酶和纤维素酶。     

Effects of rice straw particle size on digesta particle size distribution,nitrogen metabolism,blood biochemical parameters,microbial amino acid composition and intestinal amino acid digestibility in goats

Effects of rice straw particle size and physically effective neutral detergent fiber (peNDF) on particle size distribution of different digestive tract, nitrogen (N) metabolism, blood biochemical parameters, microbial amino acid (AA) composition and intestinal AA digestibility in goats were investigated. A 4 × 4 Latin square design was employed using four mature Liuyang black goats fitted with permanent ruminal, duodenal, and terminal ileal fistulae. During each of the four periods, goats were offered one of four diets that were similar in chemical composition, but varied in particle sizes and peNDF through alteration of the theoretical cut length of rice straw (10, 20, 40 and 80 mm, respectively). Dietary peNDF contents of four diets were 17.4, 20.9, 22.5 and 25.4%, respectively. Results showed that increasing particle size of rice straw and dietary peNDF significantly affected the particle size distributions of digesta in rumen, duodenum and ileum, except feces. However, increasing particle size of rice straw and peNDF did not affected N metabolism in goats, except the increased apparent N digestibility in rumen and large intestine, and the decreased apparent N digestibility in small intestine. Furthermore, increasing particle size of rice straw and peNDF showed little influence on the profile of blood biochemical parameters, microbial AA composition and intestinal AA digestibility in goats.     

Effect of different volatile fatty acids mixtures on energy metabolism in cattle

Four Friesian steers (mean BW = 282 kg) were given mixtures of VFA and casein by intragastric infusion to give a total energy input of 675 kJ/kg BW.75. Casein supplied 16.3% of the energy and 777 mg N/kg BW.75. The molar proportion of butyric acid was held constant at 8 mol/100 mol, and the acetic and propionic acids varied inversely. Acetic acid was varied in 12 increments from 11 to 91 mol/100 mol and propionic acid proportion varied inversely. Heat production, blood (urea, insulin, beta-hydroxybutyrate, free fatty acids) and urine metabolites (urea, N, VFA) were measured. There were no differences (P greater than .05) in heat production until the acetic acid proportions exceeded approximately 90 mol/100 mol, at which point there was a decrease in heat production (P less than .05) accompanied by a considerable excretion of acetic acid in the urine. Above 80 mol/100 mol acetic acid, beta-hydroxybutyrate was greatly elevated, accompanied by a small decrease in blood glucose and blood insulin together with an increase in blood free fatty acid concentration. There was also an elevation of N excretion in the urine. When the proportion of propionic acid exceeded 76 mol/100 mol there were some metabolic disturbances resulting in blood hemolysis, an increase in N excretion in the urine, and nervous disposition of the animals. It is concluded that differences in heat production between roughage and concentrate diets are not likely to be a result of differences in the energetic response to different proportions of VFA. Differences in activity during standing, feeding, and ruminating may, therefore, be more important.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ammonia, pH and volatile fatty acids in the bovine rumen after feeding with hay.

The effect of feeding level and interval between feedings on the fermentation pattern in the bovine rumen have been investigated in experiments with hay. The animals were completely adapted heifers fitted with rumen cannulas, and the parameters measured were ammonia, pH, volatile fatty acids (VFA) and non-glucogenic/glucogenic ratio (NGGR) in the VFA mixture.Increasing feeding levels, ranging from 2/3 to 4/3 of maintenance level, resulted in higher average concentrations of VFA and lower pH in the rumen fluid. Further the highest level of intake caused a considerable diurnal variation in the pH and the concentration of total VFA, and increased the variation in the molar composition of the VFA mixture.Three feeding intervals ranging from 8 to 16 hrs., with hay administered at maintenance level, caused no changes in the fermentation pattern.Typical variations in the concentrations of ammonia and valeric acid as related to time after feeding were demonstrated, but the concentrations of the branched-chain fatty acids in the rumen fluid were found to be quite constant.It may be concluded that a representative mean value of the parameters measured, except for ammonia and valeric acid, may be based on relatively few samples when feed intake does not exceed maintenance level, whereas sampling every hour is required at higher feeding levels.     

Effect of wood waste on the digestibility of glycides and level of volatile fatty acids in sheep]

Sheep were subject to an experiment concerning the effect of treated beech sawdust and thickened aqueous hydrolyzate of beech wood (xylocel) on the digestibility of glycides and on the level of volatile fatty acids (VFA) in the rumen content. The results prove that the use of treated beech sawdust as a replacer for ground barley straw favourably influenced the digestibility of monosaccharides, cellulose, lignin and total dry matter of the diet. Sawdust reduced the concentration of total VFA in the rumen content but the ratio of acetic acid to propionic acid (A:P) was lower and the energetic efficiency of the VFA produced was higher in the diet containing sawdust. The addition of urea to the diet with beech sawdust conditioned less effectively, as distinct from the case mentioned above, did not give a clear effect. Urea encouraged the digestibility of pentosanes, glucose and cellulose, but reduced the energetic efficiency of the VFA produced. Xylocel had no clear effect on the digestibility of sugars either. The higher A:P ratio and the lower energetic efficiency of the VFA produced testify to the fact that xylocel in combination with beet molasses was not a sufficient replacer of sugar-beet glycides.     

异位酸与叶酸对犊牛生长性能、氮平衡和血液指标的影响

试验旨在研究日粮添加异位酸(branched-chain volatile fatty acids, BCVFA)与叶酸(folic acid, FA)对犊牛生长性能、氮平衡与血液代谢产物的影响。试验选用16头60日龄、体重(BW)(91±5.3) kg的中国荷斯坦奶公牛,进行为期80 d的2×2因子饲养试验。结果表明:BCVFA与FA对犊牛消化氮、沉积氮、沉积氮/采食氮和沉积氮/消化氮存在交互作用(P<0.05)。BCVFA与FA显著提高了犊牛干物质采食量、日增重和饲料效率(P<0.05)。采食氮、消化氮、沉积氮、沉积氮/采食氮和沉积氮/消化氮显著增加(P<0.05);总氮排泄量显著降低(P<0.05)。血液葡萄糖、总蛋白和白蛋白显著增加(P<0.05);尿素氮浓度显著降低(P<0.05)。综上可知,20 g/d BCVFA和0.1 mg/kg BW FA均能促进犊牛生长,提高日粮氮利用率。     

Effects of rice feeding on growth performance and protein (amino acids) metabolism in weanling piglets

We investigated the effects of rice feeding on growth performance and protein (amino acids) metabolism of weanling piglets. In all, 16 weanling piglets with an average initial weight of 7.5 kg were divided into two groups. One group was fed a corn‐soybean meal‐based diet, and the other was fed a rice‐soybean meal diet, containing around 46% of corn or rice, respectively. A two‐week growth trial was conducted. The average daily gain (p = .025) and feed efficiency (p = .011) in rice‐fed piglets were significantly higher than those in corn‐fed piglets. Liver lysine‐ketoglutarate reductase activity tended to be lower (p = .073) in rice‐fed piglets than in corn‐fed piglets. Plasma urea nitrogen concentration in rice‐fed piglets was significantly lower than that in corn‐fed piglets. Plasma glucose and insulin concentrations were significantly higher in rice‐fed piglets than in corn‐fed piglets. Plasma‐free valine, isoleucine, and tryptophan concentrations were significantly higher in rice‐fed piglets than in corn‐fed piglets. In contrast, plasma histidine concentration was significantly lower in rice‐fed piglets than in corn‐fed piglets. Overall, these results show that rice feeding improves the growth performance and affects the protein (amino acids) metabolism in weanling piglets.     

收割时期和收割高度对小麦秸秆营养成分和消化率的影响

文章旨在明确收割时期和收割高度对小麦秸秆营养成分和体外消化率的影响。试验选取山农22号小麦品种作为研究对象,分别在3个成熟期进行不同收割高度的取样。收割时期分别为蜡熟期的倒数2周、1周和0周;收割高度分别为距离地面5cm、10cm和15cm。结果表明,收割时期和收割高度均影响小麦秸秆营养成分和体外消化率。小麦秸秆中可溶性糖、淀粉和粗蛋白质含量随收割时期的推迟显著下降(P<0.05)。随着收割时期的推迟,小麦秸秆中中性洗涤纤维含量和酸性洗涤纤维含量逐渐升高(P<0.05),钙和磷含量逐渐降低(P<0.05)。小麦秸秆中粗蛋白质、钙和磷含量随着收割高度的增加显著升高(P<0.05),可溶性糖、中性洗涤纤维和酸性洗涤纤维含量显著下降(P<0.05)。因此,为了获得质量较高的小麦青贮,需要在小麦蜡熟期倒数第2周,在距离地面15cm的高度收获小麦秸秆。     

Effects of housing and feeding systems on performance of neonatal Holstein bull calves

As the dairy industry continues to grow, more dairy calves are available for dairy, beef, and veal purposes. Rearing systems must be highly efficient to make this industry cost efficient, making the evaluation of rearing methods important to establish the most practical method. A study was designed and conducted to evaluate effects of housing and feeding systems on performance of neonatal Holstein bull calves. Treatments (2 × 2 factorial arrangement) consisted of: 1) individually housed, bottle-fed (n = 5 bull calves); 2) individually housed, bucket-fed (n = 5 bull calves); 3) group-housed, bottle-fed (n = 5 pens; 4 bull calves/pen); and 4) group-housed, bucket- (trough) fed (n = 5 pens; 3 or 4 bull calves/pen). Feeding treatments began on d 7 when calves had been acclimated to their new environment. Body weight measurements were collected every 7 d and blood samples were collected on d 0, 28, 55, and 66 for β-hydroxybutyrate (BHBA) concentration as a gross indicator of ruminal development. No housing × feeding interactions or feeding treatment effects were observed (P > 0.10). Average DMI (dry feed plus milk replacer) was increased (P < 0.05) for group-housed vs. individual animals after d 41, and final BW was greater (P < 0.05) for group-housed calves compared with individually housed calves. Feed efficiency and ADG, however, remained similar (P > 0.10) for all treatments. Fecal scores (P > 0.26), CV for BW (P > 0.26), and BHBA concentrations (P > 0.14) showed no differences among treatments. Housing system had greater effect on calf performance compared with milk feeding regimen.