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1.
Low selenium (Se) in soil and forage can adversely affect on the quality of animal-derived foods, and hence on human health. Lambs grazed on mixed pastures of alfalfa (Medicago sativa) and tall fescue (Festuca arundinacea) were supplemented with five levels of Se [0, 3, 6, 9 and 12 µg/kg body weight (BW)]. The intake of dry matter (DM) and organic matter (OM) varied with the level of Se supplementation, with a peak at 6 µg Se per kg BW (p ≤ 0.05). Gross energy (GE) intake, digestive energy (DE) intake and metabolic energy (ME) intake were higher at 6 µg Se per kg BW than at other Se levels (p < 0.01); in addition, methane energy (CH4-E) output was lower at 6 µg Se per kg BW. Supplementation with Se significantly increased nitrogen (N) intake, faecal N and urine N, for which the peak values were 20.2 g N/, 5.62 g N/day and 7.92 g N/day, respectively, at 6 µg Se per kg BW. Se intake, blood Se, faecal Se, urine Se and retained Se were negatively correlated with forage crude protein (CP) content (p < 0.001) but were positively correlated with the content of neutral detergent fibre (NDF) (p < 0.001) and acid detergent fibre (ADF) (p < 0.001). Thus, we recommend the addition of 6 µg Se per kg BW to sheep grazed on pastures in regions with low soil Se.  相似文献   
2.
This study aimed to investigate the effect of grape pomace powder levels and roughage sources on gas kinetics, digestibility and fermentation of swamp buffaloes by using in vitro techniques. The experimental design was a 2 × 4 factorial arrangement in a completely randomized design. Factor A was two sources of roughage (untreated rice straw, RS, and 3% urea treated rice straw, UTRS) and factor B was four levels of grape pomace powder (GPP) supplementation (0, 2, 4, 6% of substrate) on a dry matter basis. Results revealed that GPP supplementation at 2, 4 and 6% of substrate influenced gas kinetics. Cumulative gas production tended to be lower in the supplemented group. In vitro true digestibility was higher in the GPP supplementation at 2% with UTRS while microbial mass was higher in the supplemented groups. Supplementation of GPP significantly increased the total volatile fatty acids, especially propionate. Calculated methane production was subsequently decreased in the supplemented groups. Bacterial population was higher while protozoal population was lower by GPP supplementation. It could be concluded that supplementation of GPP at 2% of the substrate with UTRS improved in vitro true digestibility, rumen fermentation end‐products as well as reducing methane production.  相似文献   
3.
4.
Fifteen, one year old swamp buffalo males with average liveweight of 200.5 ± 9.5 kg were randomly assigned according to a completely randomized design to receive three dietary treatments of supplemental vegetable oils in concentrate contained 140, 750, and 16 g of crude protein, total digestible nutrient, and ether extract, respectively (T1 = unsupplemented, T2 = supplemental coconut oil and sunflower oil in ratio 50:50 at 6% of concentrate, and T3 = supplemental sunflower oil at 6% of concentrate) during a 5-month feeding trial. Urea-treated rice straw was offered ad libitum and concentrate was supplemented at 150 g/kg BW. The results revealed that supplementation of vegetable oils decreased dry matter intake in sunflower oil supplemented group. Combination of coconut oil and sunflower oil supplementation resulted in similar average daily gain as those found in control and in sunflower oil supplemented groups. Rumen microorganism population, ammonia–nitrogen, blood urea–nitrogen and total volatile fatty acid concentrations were decreased as vegetable oils were supplemented. Oil supplementation slightly reduced growth rate, hot carcass percentage, loin eye area particularly on sunflower oil supplemented group. Based on these findings, vegetable oil resulted in decreased performance of swamp buffaloes although the combination of coconut oil and sunflower oil could reduce negative effect of unsaturated oil supplementation. However, further analyses of conjugated fatty acids (CLA) in meat could offer useful information in determining pronounced effects of vegetable oil supplementation.  相似文献   
5.
This experiment was conducted to investigate the effect of coconut oil and garlic powder supplementation on digestibility of nutrients, rumen fermentation, rumen ecology, rumen microorganism and methanogen diversity. Four, 3-year old, rumen fistulated swamp buffalo bulls were randomly assigned in a 4 × 4 Latin square design to receive four dietary treatments; 7% coconut oil, 7% coconut oil with 50 g/day of garlic powder, 7% coconut oil with 100 g/day of garlic powder and non-supplemented (control). During the experiment, concentrate was offered at 0.5% of BW while rice straw was given on ad libitum basis. It was found that supplementation of 7% coconut oil had significantly influenced on total DM intake, OM, NDF and ADF digestibilites while supplementation of 7% coconut oil with garlic powder (50 and 100 g/day) were not significantly different when compared with the control. Dietary supplementations did not affect on rumen pH, NH3–N concentrations. Blood urea nitrogen (BUN) was significantly higher in supplemented groups. Total VFA concentration, proportion of acetate and acetate to propionate ratio were reduced by supplementation. Proportion of propionate was increased (P < 0.05) when supplemented with 7% coconut oil and 7% coconut oil with 100 g/day of garlic powder. Methane production was dramatically reduced (P = 0.005) in supplemented treatments and was 10% reduced in 7% coconut oil supplementation. Amylolytic and proteolytic bacteria were increased (P = 0.007 and P = 0.024) while protozoal population decreased by 68–75% (P < 0.01) by supplementation. Total bacterial population was increased by supplementation while total fungi and total methanogens were not significantly different among treatments. Percentage of cellulolytic bacterial population was not different among treatments. However, dietary supplementation reduced (P < 0.001) percentage of F. succinogenes population. However, methanogen diversity was not changed using PCR–DGGE as technique. Thirteen separate bands were found in the DGGE gel. Based on this study, supplementation with 7% coconut oil plus 100 g/day of garlic powder could be efficiently utilized in the rumen and thus, could provide good fermentation end products and improve rumen ecology for the host swamp buffaloes particularly in reducing 9% methane gas production without changing nutrient digestibilities.  相似文献   
6.
Mao pomace meal (MPM) contains condensed tannins and saponins at 92 and 98 g/kg, respectively, and these substances can be used to manipulate ruminal fermentation in ruminant. Four multiparous lactating Holstein cows with 45 ± 5 days in milk were randomly assigned according to a 4 × 4 Latin square design to receive four different levels of MPM supplementation at 0, 100, 200, and 300 g/head/day, respectively. Cows were fed with concentrate diets at 1:1.5 of concentrate to milk yield ratio and urea‐treated (3%) rice straw was fed ad libitum. The results revealed that feed intake, nutrient digestibility, blood urea nitrogen, and hematological parameters were not affected by MPM supplementation (> 0.05). However, ruminal pH and propionate were increased quadratically (< 0.05) in cows receiving MPM whereas acetate, acetate to propionate ratio and estimate methane production were decreased (p < 0.05). Supplementation of MPM linearly decreased ruminal ammonia nitrogen and protozoal population at 4 hr postfeeding (p < 0.05). Milk production and milk composition were similar among treatments (p > 0.05). In conclusion, supplementation of MPM at 200 g/head/day could modify ruminal fermentation and reduce methane production without adverse effect on feed intake, digestibility, hematological parameters, and milk production in dairy cows.  相似文献   
7.

In the next two decades, the world population will increase significantly; the majority in the developing countries located in the tropics of Africa, Asia, Latin America, and the Caribbean. To feed such a population, it is necessary to increase the availability of food, particularly high-value animal protein foods produced locally, namely meat and dairy products. Dairy production in tropical regions has a lot of growth potential, but also poses a series of problems, particularly as dairy production systems were developed in temperate countries and in most cases are difficult to implement in the tropics. Drawbacks include hot weather and heat stress, the lack of availability of adequate feeds, poor infrastructure, and cold chain and the competition with cheap imports from temperate countries. This position paper reviews the major drawbacks in dairy production for the five major dairy species: cattle, water buffalo, sheep, goat, and camel, as well as the future trends in research and development. It also concerns the major trends in reproduction and production systems and health issues as well as environmental concerns, particularly those related to greenhouse gas emissions. Tropical Animal Health and Production now launches a topical collection on Tropical Dairy Science. We aim to publish interesting and significant papers in tropical dairy science. On behalf of the editorial board of the Tropical Animal Health and Production, we would like to invite all authors working in this field to submit their works on this topic to this topical collection in our journal.

  相似文献   
8.
Three, multiparous Holstein crossbred dairy cows with initial body weight of 385 ± 19 kg were randomly allocated to 3 treatments of rice straw (T1 = untreated rice straw; T2 = 5.5% urea-treated rice straw (5 g urea in 100 ml water to 100 g air-dry (91% DM) straw); T3 = 2.2% urea + 2.2% calcium hydroxide treated rice straw (2.0 g urea and 2.0 g Ca(OH)2 in 100 ml to 100 g air-dry (91% DM) straw) according to a 3 × 3 Latin square design. Each period lasted for 21 days in which feed, feces and rumen fluid were collected during the last 7 days for chemical analyses. The findings revealed significant improvements in dry matter intake and digestibility by using 5.5% urea-treated rice straw and 2.2% urea + 2.2% calcium hydroxide treated rice straw. Ruminal pH and NH3-N were found higher (P < 0.05) as compared with urea-treated rice straw fed group, while blood urea nitrogen and milk urea nitrogen were in normal ranges. Volatile fatty acid concentrations especially those of acetic acid were decreased (P < 0.05) and those of propionic acid were increased (P < 0.05), thus acetic acid:propionic acid was subsequently lowered (P < 0.05) in cows fed with 5.5% urea-treated rice straw and 2.2% urea + 2.2% calcium hydroxide treated rice straw, respectively. Moreover, ruminal viable and cellulolytic bacterial counts were enhanced by urea and calcium hydroxide treatments. Milk protein and fat concentrations were additionally increased by respective treatments while 3.5% fat-corrected milk was highest; ranking from 2.2% urea + 2.2% calcium hydroxide treated rice straw, 5.5% urea-treated rice straw and urea-treated rice straw fed groups. Based on this study, implications could be made that using 2.2% urea + 2.2% calcium hydroxide treated rice straw for straw treatment could be an alternative treatment to 5.5% urea treatment with regards to its effectiveness and treatment cost for lactating dairy cows.  相似文献   
9.
Tropical Animal Health and Production - The objective of this study was to investigate the effect of tropical legume (Phaseolus calcaratus) mixed with ruzi grass feeding on the performance of...  相似文献   
10.
试验旨在研究香茅(Cymbopogon citratus Stapf.)粉(LGP)对瘤胃生态,瘤胃微生物和营养物质的消化率的影响。试验采用4×4拉丁方设计,选择4头安有瘘管的杂交肉牛(波罗门牛)并随机分配。设4个日粮处理组,LGP添加水平分别为0、100、200、300g·d^-1,结合尿素处理的稻草(5%)一起饲喂,试牛自由采食。试验结果显示:各处理间干物质(DM)、粗脂肪(EE)和中性洗涤纤维(NDF)的可消化性差异显著,以添加LGP100g·d^-1组最高。然而,添加LGP使粗蛋白质(CP)的可消化性显著降低(P〈0.05),且随着LGP添加量的升高,瘤胃中氨氮和尿素氮含量显著降低(p〈0.05)。  相似文献   
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