Fat and fatty acid digestibility of different fat sources in growing pigs

The effect of fat source on fat and fatty acid (FA) apparent faecal (aFD) and ileal digestibility (aID) was studied in growing pigs. Faecal and ileal digestibilities were measured, using titanium dioxide as inert marker, in intact and ileo-rectally anastomosed pigs, respectively. Five different fat sources, added at 10% to a barley based diet (B), were tested: tallow (T), high oleic sunflower oil (HOSF), sunflower oil (SO), linseed oil (LO) and a fat blend (FB; 5.5% T, 3.5% SO and 1% LO of diet).

Except for B and T, fat aFD and aID were relatively similar among diets and site of measurements and the same was observed when it was obtained from the sum of FA aFD. However fat and sum of FA aID varied according to dietary FA composition and it was inversely related with the saturated FA content, due to the lowest aID of palmitic and stearic. aID of linoleic in SO and linolenic in LO were higher than the respective FA of the other diets and no differences were observed for oleic acid. The aFD of the unsaturated FA was higher than the corresponding aID values, despite similar fat aID and aFD. This together with the lower (in some cases negative) aFD of stearic acid suggest that there is biohydrogenation of unsaturated FA in the hindgut. Measurement at the end of the ileum should give a better estimation of digestibility of fat and FA than at the faecal level.     

排酸处理对湘南黄牛氨基酸以及脂肪酸的影响

[目的]为改善湘南黄牛肉用品质,并在生产中推广应用。[方法]试验选取6头同一品种、月龄接近的湘南黄牛经同一饲喂条件育肥后进行屠宰,测定排酸前后牛肉中氨基酸、脂肪酸含量等指标。[结果]结果表明,排酸牛肉组氨酸、甘氨酸、蛋氨酸、肌氨酸、色氨酸、∑鲜味氨基酸、∑苦味氨基酸含量显著升高(P0.05);丙氨酸、缬氨酸、脯氨酸、苏氨酸、瓜氨酸、∑甜味氨基酸含量显著降低(P0.05)。排酸牛肉十二酸、十四酸、十五酸、顺-11-二十碳烯酸、饱和脂肪酸(SFA)含量显著升高(P0.05);顺-9,12,15-十八碳三烯酸、顺-8,11,14-二十碳三烯酸、顺-5,8,11,14-二十碳四烯酸、二十碳五烯酸、二十二碳六烯酸、多不饱和脂肪酸(PUFA)、PUFA/SFA、n-6 PUFA、n-3 PUFA含量显著降低(P0.05)。[结论]最终得出,通过排酸处理湘南黄牛能够满足人体从肉类摄取氨基酸的需求,同时有效改变脂肪酸含量,提高肉用品质。     

灌注寡肽与游离氨基酸对来航公鸡氨基酸吸收及循环中肽的影响

试验比较研究了在麻醉条件下来航公鸡十二指肠灌注酪蛋白水解物寡肽（COP）与游离氨基酸（FAA）对门静脉血液中氨基酸和肽的影响。结果表明：灌注后10分钟，COP组门静脉总氨基酸（TAA）含量显著地（P＜0．05）高于相同组成的等摩尔浓度的FAA1组和等百分浓度的FAA2组。FAA2与FAA1组相比，一些氨基酸含量有升高的趋势，但仅个别氨基酸显著（P＜0．05）高于FAA1组。COP组门静脉血浆游离氨基酸含量，除赖氨酸、色氨酸、酪氨酸、脯氨酸、组氨酸外，其它氨基酸都显著（P＜0．05）或极显著（P＜0．01）高于FAA1和FAA2组。在饥饿状态及灌注COP和FAA1、FAA2后，门静脉血浆中肽结合氨基酸（PBAA）分别占39．23％，35．63％，45．89％和52．63％。其中谷氨酸、丝氨酸、丙氨酸、甘氨酸比例较高，它们与其它一些氨基酸存在显著（P＜0．05）或极显著（P＜0．01）正相关。GPLC分析结果显示：灌注COP和FAA后门静脉血浆的肽量均极显著地（P＜0．01）高于饥饿对照状况，COP组鸡门脉血浆中总量和一些肽量显著高于FAA组（P＜0．01）。试验证实，鸡村寡肽的氨基酸吸收快于游离氨基酸，一部分可以完整的形式吸收进入血液循环。给予肠道FAA也会改变循环中的肽量。     

The interaction between maternal and post‐hatch n‐3 fatty acid supplementation in broiler diets

This study investigated whether offspring from n‐3‐supplemented breeders have an enhanced performance and immune organ weight when fed a post‐hatch n‐3‐enriched diet in comparison with their control‐fed counterparts and the importance of timing of omega‐3 supplementation. Therefore, 480 Ross‐308 broiler breeder hens were fed one of four different diets (120/treatment). The control diet (CON) was a basal diet, rich in n‐6 fatty acids (FA). The three other diets were enriched in n‐3 FA, formulated to obtain a different EPA/DHA ratio of 1/1 (EPA = DHA), 1/2 (DHA) or 2/1 (EPA). At 33 weeks of age, eggs were incubated to obtain 1440 offspring. They were set up according to their maternal diet and sex in 48 pens of 30 chicks each (12 pens per maternal treatment: six male and six female). Half of the offspring were given a post‐hatch control diet, whereas to other half received an n‐3‐supplemented diet. Zootechnical performance was followed for starter, grower and finisher phase, and at the end of each phase two, chicks per pen were sacrificed to determine the weight of the immune organs. No interaction was found between maternal and post‐hatch n‐3 treatment for zootechnical performance. An interaction arose between the maternal and post‐hatch n‐3 supplementation for proportional bursa weight at day 1 and day 14 and proportional liver weight at day 14, but effects on immune organ weight were rather limited. Offspring post‐hatch n‐3 supplementation did not enhance maternal n‐3 supplementation.     

喷雾干燥鱼浆蛋白粉营养成分分析

本试验对鱼粉加工废水鱼浆蛋白粉(经浓缩、水解、喷雾干燥得到的副产品)进行营养成分分析,其中粗蛋白质含量达64.08%,钙2.67%、磷1.12%,钙磷比例合理;各氨基酸含量分别为:赖氨酸3.29%,蛋氨酸0.94%,谷氨酸5.17%,牛磺酸2.50%。     

Fermentation characteristics of resistant starch,arabinoxylan, and β-glucan and their effects on the gut microbial ecology of pigs: A review

Dietary fibers (DF) contain an abundant amount of energy, although the mammalian genome does not encode most of the enzymes required to degrade them. However, a mutual dependence is developed between the host and symbiotic microbes, which has the potential to extract the energy present in these DF. Dietary fibers escape digestion in the foregut and are fermented in the hindgut, producing short-chain fatty acids (SCFA) that alter the microbial ecology in the gastrointestinal tract (GIT) of pigs. Most of the carbohydrates are fermented in the proximal part, allowing protein fermentation in the distal part, resulting in colonic diseases. The structures of resistant starch (RS), arabinoxylan (AX), and β-glucan (βG) are complex; hence, makes their way into the hindgut where these are fermented and provide energy substrates for the colonic epithelial cells. Different microbes have different preferences of binding to different substrates. The RS, AX and βG act as a unique substrate for the microbes and modify the relative composition of the gut microbial community. The granule dimension and surface area of each substrate are different, which influences the penetration capacity of microbes. Arabinose and xylan are 2 different hemicelluloses, but arabinose is substituted on the xylan backbone and occurs in the form of AX. Fermentation of xylan produces butyrate primarily in the small intestine, whereas arabinose produces butyrate in the large intestine. Types of RS and forms of βG also exert beneficial effects by producing different metabolites and modulating the intestinal microbiota. Therefore, it is important to have information of different types of RS, AX and βG and their roles in microbial modulation to get the optimum benefits of fiber fermentation in the gut. This review provides relevant information on the similarities and differences that exist in the way RS, AX, and βG are fermented, and their positive and negative effects on SCFA production and gut microbial ecology of pigs. These insights will help nutritionists to develop dietary strategies that can modulate specific SCFA production and promote beneficial microbiota in the GIT of swine.     

多不饱和脂肪酸的生物学功能及其在鸡生产中的应用研究进展简

多不饱和脂肪酸是一种具有特殊生物学功能的物质,在机体免疫调节、细胞增长、基因调控、脂质代谢及抗癌等方面都具有重要的作用,作者简述了多不饱和脂肪酸的生物学功能及其在鸡生产中的应用研究进展,包括对鸡生产性能、蛋肉品质和免疫机制等方面的调节作用。     

发酵麸皮多糖对肉羊肉品质、肌肉氨基酸组成及肌肉抗氧化酶和肌纤维类型相关基因表达的影响

试验旨在研究发酵麸皮多糖(FWBP)对肉羊肉品质、肌肉氨基酸组成及肌肉抗氧化酶和肌纤维类型相关基因表达的影响。选用50只体重为(20.17±3.33)kg的6周龄杜泊×小尾寒羊F1代杂交羔羊,随机分为5组,每组10只。对照组(Ⅰ组)饲喂基础饲粮,试验组(Ⅱ、Ⅲ、Ⅳ、Ⅴ组)分别饲喂在基础饲粮中添加50、100、200、400 mg/kg FWBP的试验饲粮,预试期14 d,正试期56 d。结果表明:1)Ⅱ和Ⅲ组肉羊背最长肌剪切力显著低于Ⅰ组(P<0.05)。2)Ⅱ、Ⅲ和Ⅳ组肉羊背最长肌中蛋氨酸(Met)含量显著高于Ⅰ组(P<0.05);Ⅳ组肉羊背最长肌中的半胱氨酸(Cys)含量显著高于Ⅰ组(P<0.05),而谷氨酸(Glu)和亮氨酸(Leu)含量显著低于Ⅰ组(P<0.05);Ⅴ组肉羊背最长肌中丝氨酸(Ser)含量显著高于Ⅰ组(P<0.05),而缬氨酸(Val)含量显著低于Ⅰ组(P<0.05)。3)各试验组肉羊背最长肌中过氧化氢酶(CAT)的mRNA相对表达量显著高于Ⅰ组(P<0.05),且Ⅲ组肉羊背最长肌中CAT的mRNA相对表达量显著高于Ⅱ、Ⅳ、Ⅴ组(P<0.05)。Ⅲ组肉羊背最长肌中谷胱甘肽过氧化物酶(GSH⁃Px)和超氧化物歧化酶(SOD)的mRNA相对表达量显著高于Ⅰ组(P<0.05)。4)Ⅲ组肉羊背最长肌中肌球蛋白重链(MyHC)Ⅰ和MyHCⅡa的mRNA相对表达量显著高于Ⅰ组(P<0.05),且MyHCⅡx的mRNA相对表达量显著低于Ⅰ组(P<0.05)。Ⅲ、Ⅳ和Ⅴ组肉羊背最长肌中MyHCⅡb的mRNA相对表达量显著高于Ⅰ组(P<0.05)。综上所述,饲粮中添加FWBP可以降低肉羊背最长肌剪切力,改善其氨基酸组成,提高肌肉抗氧化能力,诱导Ⅱx型肌纤维向Ⅰ和Ⅱa型肌纤维的转化,且以添加100 mg/kg效果较佳。     

Calcium salts of fatty acids with varying fatty acid profiles in diets of feedlot-finished Bos indicus bulls: impacts on intake,digestibility, performance,and carcass and meat characteristics

We hypothesized that the inclusion of calcium salts of fatty acid (CSFA) into the diets and the fatty acid (FA) profile of the supplements would impact performance and meat characteristics of Bos indicus bulls. Hence, the objective was to evaluate the effects of CSFA profiles on intake, body weight (BW), carcass, and meat characteristics of feedlot-finished B indicus bulls. Fifty-three Nellore bulls [initial BW 315 ± 5.9 kg and 20 ± 2 mo] were used. At the beginning, 6 bulls were randomly chosen and slaughtered for determination of their BW composition, and the remaining 47 bulls were evaluated during a 140-d experimental period. The bulls were placed in individual pens, blocked according to initial BW and randomly allocated to 1 of the 3 following treatments: (1) control diet containing sugarcane bagasse, ground corn, citrus pulp, peanut meal, and mineral–vitamin mix (CON), (2) CON with the addition of 3.3% of CSFA from soybean oil (CSO), or (3) CON with the addition of a mixture of 3.3% of CSFA from palm, soybean, and cottonseed oils (CPSCO). Diets were offered ad libitum and formulated to be isonitrogenous. Bulls supplemented with CSFA had a greater (P < 0.01) final BW, dry matter intake, average daily gain (ADG), feed efficiency (FE), and FA intake vs. CON. Among carcass parameters, CSFA-supplemented bulls had greater (P < 0.01) carcass ether extract concentration vs. CON bulls. When the CSFA profile was evaluated (CSO vs. CPSCO), CPSCO bulls had a better (P ≤ 0.03) FE, carcass ADG, and hot carcass weight (HCW) vs. CSO bulls. The FA intakes differed among CSFA treatments, as the total saturated, palmitic, and oleic FA intakes were greater for CPSCO (P < 0.01), whereas lower intakes of total unsaturated and polyunsaturated FA (P < 0.01) were observed for CPSCO vs. CSO. Samples from the Longissimus muscle contained greater palmitoleic (P = 0.01) and reduced linoleic (P = 0.02) FA concentrations in CSFA-supplemented bulls vs. CON bulls. In agreement with the FA intakes, CPSCO-supplemented bulls had a greater (P ≤ 0.05) unsaturated FA concentration vs. CSO in Longissimus muscle. In summary, CSFA supplementation improved the performance of finishing B. indicus bulls vs. CON. Moreover, the inclusion of CSFA from palm, soybean, and cottonseed oil benefited the FE, carcass ADG, and HCW compared with the inclusion of CSFA from soybean oil, demonstrating the potential of specific FA for improving the performance and meat quality of B. indicus bulls.     

肉仔鸡对不同形态蛋白质吸收率的研究

为评价肉仔鸡对不同形态蛋白吸收差异性,将100只艾维茵雄肉仔鸡随机分为4个处理组,每个处理5个重复,每个重复5只鸡,进行氨基酸、酪蛋白和肽三种蛋白源的吸收率对比研究。结果表明:肉鸡对氨基酸组日粮总蛋白吸收率极显著高于肽组和酪蛋白组(P<0.01) ,总蛋白吸收率分别提高5.10 %和5.27 %;肽组和酪蛋白组日粮中多数氨基酸吸收率均显著(P<0.05)或极显著(P<0.01)低于氨基酸组的吸收率;相对而言,肽组和酪蛋白组中的天门冬氨酸、苏氨酸、丝氨酸、谷氨酸、甘氨酸、缬氨酸、脯氨酸、异亮氨酸和胱氨酸等吸收率同氨基酸组相比差异幅度较大。肽组日粮同酪蛋白组日粮总蛋白吸收率间无显著差异(P>0.05)。以上结果表明,游离氨基酸在肉仔鸡肠道中吸收率高于完整蛋白和肽,游离氨基酸具有吸收优势。