Alpha‐lipoic acid: An inimitable feed supplement for poultry nutrition

Alpha‐lipoic acid (ALA) is a multifunction antioxidant that is produced in small amount by cells as well as its dietary provision facilitates fatty acid mobilization, energy expenditure as well as can scavenge free radicals in poultry birds. It exists in oxidized as well as reduced form, characterized by growth promoting, anti‐inflammatory, antioxidative, immunostimulatory, and hypocholesterolemic properties when fed as dietary supplement to farm animals particularly chicken birds. Recently, several studies reported that dietary supplementation of ALA can influence growth performance indicators, immunological, biochemical characteristics, lipid metabolism, and oxidative stress as well as increase antioxidant potential and storability of poultry meat and meat products. Accordingly, this paper adds the reviews and discusses the outcomes of studies documenting the effect of lipoic acid dietary fortification on growth performance, biochemical, and immunological characteristics as well as the effects on lipid peroxidation of fresh meat and meat‐based products. Furthermore, this paper also describes the possibilities of utilization of ALA as a feed additive in poultry nutrition to improve the growth performance of poultry as well as meat quality of resultant chicken birds.     

Efficacy of feed enzymes in pig and poultry diets containing distillers dried grains with solubles: a review

Distiller's dried grains with solubles (DDGS), a coproduct of the ethanol industry, are often used as feed material in livestock and poultry nutrition. Results of many experiments have indicated, however, that a high dietary level of DDGS can negatively affect the digestibility of nutrients and the performance of monogastric animals due to their high content of non‐starch polysaccharides (NSP). Nevertheless, using high levels of DDGS as a protein source in livestock diets can be still economically justifiable in view of the rising prices of soya bean meal and other protein sources. The aim of some recent experiments with poultry and pigs was to improve the nutritional efficacy of high‐NSP diets through the addition of feed enzymes. As presented and discussed in this review article, the efficacy of feed enzymes added to poultry and pig diets containing DDGS is not consistent and depends on many factors. However, NSP‐hydrolysing enzymes generally seemed to be more efficient than phytases in terms of the digestibility of nutrients and the growth performance of poultry and pigs fed high‐DDGS diets. For this reason, supplementation with NSP‐hydrolysing enzymes could be an efficient way to enable the use of increased levels of DDGS in poultry and pig diets.     

Dietary integration with oregano (Origanum vulgare L.) essential oil improves growth rate and oxidative status in outdoor‐reared,but not indoor‐reared,pigs

The effects of a diet supplemented with oregano essential oil on performance, oxidative status, pork quality traits and sensorial properties were evaluated. In two studies, 72 pigs in indoor or outdoor conditions were assigned to either a control diet or an identical diet supplemented with 0.2% oregano essential oil. Pigs reared outdoor showed lower live weight, average daily gain and average gain:feed ratio compared to indoor pigs. The oregano supplementation improved the growth performance of the outdoor‐ but not the indoor‐reared animals. The serum oxidative status was influenced by the diet. A higher oxidative stability was observed in the oregano‐supplemented groups. As for the rearing conditions, the data suggest that after an initial adapting period, the free‐range farming systems could be better tolerated by pigs. Meat derived from pigs reared outdoor showed higher pH and a* values. Lightness was influenced by both the diet and the rearing conditions. The control group reared indoor showed shear force values higher than both supplemented groups, while no differences were detected with the control group reared outdoor. In the consumer test performed under blind conditions, the oregano groups achieved higher consistency scores compared with the control. Under informed conditions, the meat derived from the oregano‐supplemented pigs reared outdoor received the highest scores for consistency and overall liking regardless of the rearing system. The same result for the overall liking score was obtained in the expectation test. The data obtained showed that dietary oregano essential oil can be effective in reducing performance losses due to the outdoor‐rearing system, increasing the oxidative status of the animal and oxidative stability of the meat, without modifying the meat quality traits and improving consumer perceptions of the meat quality.     

The effect of metal-containing nanoparticles on the health,performance and production of livestock animals and poultry

The application of high doses of mineral feed additives in the form of inorganic salts increases the growth performance of animals, but at the same, due to their low bioavailability, can contaminate the environment. Therefore, there is a need to find a replacement of administering high doses of minerals with an equally effective alternative. The application of lower doses of metal-containing nanoparticles with the same effect on animal production could be a potential solution. In the present review, zinc, silver, copper, gold, selenium, and calcium nanoparticles are discussed as potential feed additives for animals. Production of nanoparticles under laboratory conditions using traditional chemical and physical methods as well as green and sustainable methods – biosynthesis has been described. Special attention has been paid to the biological properties of nanoparticles, as well as their effect on animal health and performance. Nano-minerals supplemented to animal feed (poultry, pigs, ruminants, rabbits) acting as growth-promoting, immune-stimulating and antimicrobial agents have been highlighted. Metal nanoparticles are known to exert a positive effect on animal performance, productivity, carcass traits through blood homeostasis maintenance, intestinal microflora, oxidative damage prevention, enhancement of immune responses, etc. Metal-containing nanoparticles can also be a solution for nutrient deficiencies in animals (higher bioavailability and absorption) and can enrich animal products with microelements like meat, milk, or eggs. Metal-containing nanoparticles are proposed to partially replace inorganic salts as feed additives. However, issues related to their potential toxicity and safety to livestock animals, poultry, humans, and the environment should be carefully investigated.     

Effect of dietary canola oil on long‐chain omega‐3 fatty acid content in broiler hearts

Young and healthy broilers are susceptible to sudden death syndrome (SDS), which is caused by cardiac arrhythmia. The long‐chain ‘fish‐type’ omega‐3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have cardioprotective anti‐arrhythmic effects in animals and humans. Raising the cardiac level of EPA and DHA in chickens may protect against SDS. However, fish oil as a source of EPA and DHA in poultry feed is costly and introduces undesirable properties to the meat. Whilst omega‐3 vegetable oils, such as canola oil, are cheaper and do not have a strong odour, they contain the short‐chain fatty acid α‐linolenic acid, which requires conversion to EPA and DHA after ingestion. We investigated the capacity for dietary canola oil to elevate cardiac EPA and DHA in broilers. Broilers were fed with diets containing either 3% canola oil or tallow, which is currently used in some commercial feeds. Upon completion of a 42 day feeding trial, canola oil significantly increased EPA and EPA + DHA in heart phospholipids relative to tallow. The elevation in cardiac EPA and EPA + DHA may provide anti‐arrhythmic effects and protect against SDS in poultry. This proof‐of‐concept biochemical study suggests that a larger study to assess the clinical outcome of SDS may be warranted.     

畜禽氧化应激与炎症及多酚的干预作用

氧化应激是畜禽体内活性氧产生与保护机制消除的失衡,可导致组织产生氧化损伤,最终诱发炎性疾病。氧化应激可激活多种转录因子,导致炎症途径相关基因的差异表达,由氧化应激引起的炎症是许多慢性疾病的病因。多酚作为植物次生代谢产物,被认为是有效的辅助治疗佐剂,在人和动物中发挥潜在的抗氧化和抗炎作用。多酚也被认为是具有应用潜力的畜禽饲料添加剂。综述了畜禽氧化应激与炎症的关系及机制、多酚对畜禽的抗氧化和抗炎作用及机制,以期为动物疾病抗氧化疗法的应用和新型抗炎药物的开发提供参考。     

Biochemical proximates of pumpkin (Cucurbitaeae spp.) and their beneficial effects on the general well‐being of poultry species

There is a growing need to increase productivity in poultry. Growth hormones and antibiotics have the ability to improve health, weight gain and feed efficiency in meat‐producing animals. The growth‐promoting antibiotics are administered to poultry to improve the general performance of the chicken. However, the use of the xenobiotic drugs in food‐producing animals has been a concern and a sensitive issue of debate for several decades in the EU and many other regional blocks of the world. Consequently, the use of hormones in animal production has been banned in Italy, Denmark and Germany for over 4–5 decades, while Belgium and Greece had never permitted its use for livestock fattening purposes. Bioactive phytochemicals exhibit antimicrobial, antioxidant, antiparasitic, antiprotozoal, antifungal and anti‐inflammatory properties and consequently have several beneficial effects on appetite, growth and the immune status of the animal. In South Africa, different species of pumpkin are produced for food due to their high nutrient content. The flesh serves as a traditional food, while the seeds and peels are commonly discarded. Pumpkin seed extract is reported to be useful for immunomodulation, reproductive health, therapeutics over a wide range of disease conditions and stimulates metabolism of accumulated fats. Studies have also shown that pumpkin seeds are a valuable source of protein and fat. Their complexity and extent of bioactivity offers sustainable prospects for natural control of pathogenic/parasitic organisms, stimulate nutrition or enhance resistance to disease infections, and reduce abdominal fat and serum levels of harmful lipids, while increasing serum levels of beneficial lipids.     

Potential of plant polyphenols to combat oxidative stress and inflammatory processes in farm animals

Polyphenols are secondary plant metabolites which have been shown to exert antioxidative and antiinflamma tory effects in cell culture, rodent and human studies. Based on the fact that conditions of oxidative stress and inflammation are highly relevant in farm animals, polyphenols are considered as promising feed additives in the nutrition of farm animals. However, in contrast to many studies existing with model animals and humans, potential antioxidative and antiinflammatory effects of polyphenols have been less investigated in farm animals so far. This review aims to give an overview about potential antioxidative and antiinflammatory effects in farm animals. The first part of the review highlights the occurrence and the consequences of oxidative stress and inflammation on animal health and performance. The second part of the review deals with bioavailability and metabolism of polyphenols in farm animals. The third and main part of the review presents an overview of the findings from studies which investigated the effects of polyphenols of various plant sources in pigs, poultry and cattle, with particular consideration of effects on the antioxidant system and inflammation.     

色氨酸的生理功能及其在畜禽饲粮中的应用

色氨酸作为一种功能性必需氨基酸,可提高动物生长性能、调节采食与泌乳、增强机体抗氧化和免疫功能等。色氨酸作为饲料添加剂应用于低蛋白质饲粮中,在保证动物正常生产性能情况下,可减少蛋白质饲喂量,缓解蛋白质饲料原料紧缺问题,减轻养殖废弃物对环境造成的污染。本文从色氨酸在畜禽体内的代谢途径及其对畜禽的生理功能等方面进行综述,为色氨酸在畜牧生产中的科学合理应用提供参考。     

Selected problems of B vitamins in animal nutritionQuelques problemes sur les apports alimentaires de vitamines BAusgewählte Probleme der B-Vitamine in der Tierernährung

Studies on vitamin B₆ and pantothenic acid conducted with pigs, poultry and veal calves are presented to demonstrate the difficulties involved in research on B vitamins. The analysis of the B vitamins already poses problems, so that recommendations on dietary requirement must be seen in the light of the respective analytical procedures used. A distinction must be made between the minimum and optimum requirements of the animals. Today, the dietary provision of the optimum requirements is of priority and needs suitable and sensitive biochemical criteria or performance criteria for assessment.Studies using early-weaned and market pigs demonstrate that, in the case of vitamin B₆, the urinary xanthurenic acid secretion after a tryptophan load and the activities of the serum transaminases are suitable biochemical criteria to diagnose suboptimum supply. Though these criteria were less responsive in poultry than in pigs, nevertheless, when the supply of vitamin B₆ was suboptimal in broiler chicken, the body's retention of dry matter, nitrogen and energy, providing measures of true performance, proved to be affected adversely.The assessment of the optimum vitamin B requirement for practical feeding rations is illustrated with results from studies on the pantothenic acid requirement of broilers and market pigs. On the basis of live weight gain and feed efficiency, and also taking into consideration biochemical criteria provided by pantothenic acid and coenzyme A levels in the blood and liver, an optimum pantothenic acid requirement of 8 mg per kg of feed is recommended for broilers and 9 mg per kg of feed for market pigs. The dietary requirement of piglets, market pigs and broilers for vitamin B₆ is estimated to be 3 mg per kg of feed.     

Strategies to modulate the intestinal microbiota and their effects on nutrient utilization,performance, and health of poultry

Poultry is widely produced and consumed meat global y. Its demand is expected to continue increasing to meet the animal protein requirement for ever-increasing human population. Thus, the chal enge that poultry scientists and industry face are to produce sufficient amount of poultry meat in the most efficient way. In the past, using antibiotics to promote the growth of poultry and manage gut microbiota was a norm. However, due to concerns over potential fatalistic impacts on food animals and indirectly to humans, their use as feed additives are banned or regulated in several jurisdictions. In this changed context, several alternative strategies have been proposed with some success that mimics the functions of antibiotics as growth promoters and modulate gut microbiota for their beneficial roles. These include the use of probiotics, prebiotics, organic acids, and exogenous enzyme, among others. Gut microbiota and their metabolic products improve nutrient digestion, absorption, metabolism, and overal health and growth performance of poultry. This paper reviews the available information on the effect of feed additives used to modulate intestinal microbiota of poultry and their effects on overal health and growth performance. Understanding these functions and interactions wil help to develop new dietary and managerial strategies that wil ultimately lead to enhanced feed utilization and improved growth performance of poultry. This review wil help future researchers and industry to identify alternative feed ingredients having properties like prebiotics, probiotics, organic acids, and exogenous enzymes.     

Microbial and nutritional aspects of feeding fermented feed (poultry by‐products) to pigs

Summary

Broiler by‐products (heads, feet, and viscera) mixed with 4% dextrose were pasteurized for 4 min at 90°C core temperature, cooled to 20°C, and fermented with Lactobacillus plantarum as starter culture. These fermented poultry by‐products were fed to 12 individually housed fattening pigs as part (17.6% of the dry matter) of their fattening ration, the remainder composed of compound pig feed. Control pigs received a compound pig feed only. Both groups of pigs were fed restrictively on the basis of body weight. The technical results of the pigs fed the experimental diet showed a significantly improved feed:gain ratio (2.46 vs 2.57), a significantly higher carcass weight (86.1 vs 81.8 kg), a lower meat percentage (50.9 vs 52.5%) and an increased backfat thickness (21.5 vs 18.7%). The bacterial flora in the intestinal tract of the pigs fed the experimental diet differed significantly from the control animals. Decreased colony counts of mesophilic aerobic bacteria, Enterobacteriaceae, enterococci and lactobacilli were found in the rectal content and the prevalence of salmonella was lower.

It is suggested that the improved feed:gain ratio and the reduced bacterial activity of the measured groups of bacteria is a result of 1) the higher energy content of the diet, and(or) 2) an assumed enhanced digestibility of nutritional components in the diet, and(or) 3) the lower incidence of diarrhea in the pigs fed with fermented poultry by‐products. This resulted in a lower contamination level of enteropathogenic bacteria like, salmonella and Escherichia coli, in the gastro‐intestinal tract of the pigs fed fermented poultry by‐products.     

血根碱的作用机制及其在动物营养上的应用效果

血根碱是一种苯菲啶异喹啉类生物碱,具有抗菌、抗氧化以及抗炎症的作用,并被用来控制血吸虫,此外血根碱还具有抗肿瘤特性。血根碱作为饲料添加剂,在猪禽饲养管理中替代抗生素已取得了良好效果。本文就对血根碱的主要作用及其机制,以及其在动物营养上的应用进行综述。     

Effect of a high-fat diet on the performance response to porcine somatotropin (PST) in finishing pigs

One hundred sixty pigs were used in a 2 x 2 factorial design to compare the performance response to daily injection of porcine somatotropin (PST); (0 or 2 mg/d) in animals fed a 14% CP corn-soy diet (control, C) to those fed a diet with 10% added fat (F) and calorie:protein and lysine:protein ratios similar to that of the C diet. Treatments, assigned randomly to 20 pens (n = 5/treatment) of eight pigs each, were initiated at 90 kg body weight and continued for 28 d. Responses to PST and dietary fat were typical. These include improved gain and feed efficiency and decreased feed intake. The effects of dietary fat on intake and efficiency were accounted for largely by the difference in energy density of these diets. Across diets, PST treatment resulted in a 13% improvement in ADG (P less than .001), a 13% decrease in feed intake (P less than .0001) and a 22% improvement in efficiency (P less than .0001). Of particular interest were the additive (PST x diet interaction, P less than .2) effects of PST and dietary fat on gain in these animals. Pigs treated with PST that were fed the F diet had greater rates of gain than did PST-treated pigs fed the C diet (P less than .05). Treatment with PST increased ADG by 9% in pigs consuming the C diet vs 16% in pigs fed the F diet. Similarly, dietary fat resulted in 4 and 11% increases in ADG in pigs treated with 0 or 2 mg of PST/d.(ABSTRACT TRUNCATED AT 250 WORDS)     

复合型抗应激添加剂对夏季蛋鸡产蛋性能、蛋品质及血清生化指标的影响

为了研究复合型抗应激添加剂对夏季蛋鸡产蛋性能、蛋品质及血清生化指标的影响,试验选用120只42周龄伊莎褐蛋鸡,随机分为2组,每组设6个重复,每个重复lO只;对照组饲喂基础日粮,试验组饲喂基础日粮＋80mg／kg复合型抗应激添加剂——禽专用添佳安肽,试验期为60d。结果表明：与对照组相比,试验组产蛋率显著提高5．56％（P〈0．05）,料蛋比显著降低4．74％（P〈0．05）,但对采食量和平均蛋重无显著影响（P〉0．05）;试验组蛋壳强度显著提高15．27％（P〈O．05）,但对蛋壳厚度、蛋白高度、哈夫单位无显著影响（P〉0．05）;试验组血清皮质醇水平显著下降53．91％（P〈0．05）,T_3、T_4水平分别显著下降20．12％、23．57％（P〈0．05）,尿素氮水平显著下降35．35％（P〈0．05）,但对血糖水平无显著影响（P〉0．05）。说明蛋鸡日粮中添加复合型抗应激添加剂——禽专用添佳安肽,具有显著抗热应激效应和增加蛋鸡采食量的作用。     

热应激对猪禽肠道健康的影响及其机制研究进展

热应激是影响猪禽夏季生产性能的重要因素,主要表现为采食量降低、生长放缓、饲料转化率降低、抗病能力减弱。肠道作为机体营养物质消化吸收的主要位点及免疫防御的第一道屏障,成为近年猪禽热应激的研究热点。本文从消化吸收功能和屏障功能两方面综述最近有关热应激对猪禽肠道健康的影响及其机制,为生产实践提供一定的理论参考。     

几种多肽类抗生素添加剂在饲料中的应用研究

杆菌肽、维吉尼亚霉素等四种多肽类抗生素因具有促进畜禽生长、在畜禽体内残留量较小、不易产生耐药性等特点,被批准为可以在饲料中长时间添加使用的饲料药物添加剂。本文就多肽类抗生素在畜禽生产中的应用研究在《饲料药物添加剂使用规范》中的用法用量作一综述,为正确合理使用该类药物,保障畜产品质量提供参考。     

Changes in diarrhea,nutrients apparent digestibility,digestive enzyme activities of weaned piglets in response to chitosan‐zinc chelate

A total of 120 weanling barrows weighing 6.11 ± 0.20 kg were randomly allotted to four treatments with three replications (i.e. pen) of ten piglets per replicate. Pigs were received corn‐soybean basal diet (control) or the same basal diet supplemented with the following sources of zinc: (i) 100 mg/kg of Zn as ZnSO₄; (ii) 100 mg/kg of Zn as chitosan‐Zn chelate (CS‐Zn); and (iii) 100 mg/kg of Zn as ZnSO₄ mixed with chitosan (CS + ZnSO₄). The results showed that CS‐Zn could highly improve average daily gain and average daily feed intake than those of ZnSO₄ or CS+ ZnSO₄ (P < 0.05). The pigs fed dietary CS‐Zn had lower diarrhea incidence and higher apparent digestibility of crude protein than those of the pigs fed dietary ZnSO₄ (P < 0.05). The protease activities in duodenal content of the pigs receiving CS‐Zn diets was higher than that of the pigs fed dietary ZnSO₄ or CS + ZnSO₄ (P < 0.05). The amylase activity in duodenal content of the pigs fed dietary CS‐Zn was higher than that of the pigs receiving ZnSO₄ diets or basal diets (P < 0.05). These results indicated that dietary CS‐Zn showed different bioactivities from ZnSO₄ or CS + ZnSO₄ in reducing the incidence of diarrhea, improving activities of digestive enzymes and growth performance of weaned pigs.     

The effect of a natural feed additive (Macleaya cordata), containing sanguinarine,on the performance and health status of weaning pigs

The aim of this study was to investigate the efficacy of Sangrovit^®, a plant‐derived feed additive, given throughout the nursery stage via feed at 15 ppm and 50 ppm, on the health status and performance of weaners against negative controls. In a 900‐sow farrow‐to‐finish farm, a total of 864 piglets were divided into three groups: (i) negative controls (NC); (ii) Sang 15: same feed as NCs, plus 15 g Sangrovit^® /t of feed; (iii) Sang 50: same feed as NCs plus 50 g Sangrovit^® /t of feed. The results indicated that administration of 50 ppm^‐Sangrovit^® had the most beneficial effects on growth performance in weaning pigs. Specifically there was increase of body weight and average daily gain, as well as reduction of feed conversion ratio. Blood analysis from the Sang groups and especially the Sang 50 group revealed low values of haptoglobin and serum amyloid A.