The Effect of Non-starch Polysaccharides Derived From Different Grains on Performance and Digestive Activity in Laying Hens

An experiment was conducted to observe the effect of non-starch polysaccharides (NSP) onperformance and digestive activity of laying hens. Thirty-two ISA Brown hens were individually cagedand offered four diets (wheat-based, millrun-based, barley-based, and barley-enzymes diets) for 10weeks. The present experiment was assigned in a completely randomized design with 8 replicates perdietary treatment. Wheat- and barley diets caused significantly higher (P0.05). Birds fed the barley-based diet had lower weight gain (P<0.05) and highercaecal weight (P<0.05) than those given other diets. Enzyme supplementation on barley dietssignificantly (P<0.05) reduced jejunal digesta viscosity and caecal weight, increased weight gain(P<0.05) and ileal digesta DM (P<0.01), and numerically reduced excreta moisture. The current studydemonstrated that NSP have a profound effect on digesta viscosity, performance, and digestive organs ofbirds; however, the NSP action may be modified by an interaction with each other and with other cellwallcomponents of grains in the gut. Enzyme supplementation reduced the negative effect of digestaviscosity

Effect of Mash Dietary Fiber on Performance and Cannibalism in Laying Hens

An experiment was conducted to observe the effect of dietary fiber given in mash form onperformance and cannibalism mortality in laying hens. Three different diets: a wheat-based diet, a guargum diet (a wheat-based diet + 20 g/kg guar gum) and a lucerne meal diet (a wheat-based diet + 40 g/kglucerne meal) in mash form were offered for 12 weeks. The results showed that birds fed guar gum diethad the lowest intake (p0.05)on feed to egg ratio and cannibalism mortality, but numerically the birds fed the guar gum diet had thehighest mortality (11.3%) and the lucerne diet had the lowest (6.9%). The lack of profound differenceswas probably due to the diets were given in mash form. In conclusion, diets containing high soluble NSPreduced the performance and increased the mortality due to cannibalism in laying hens. The use of mashform may have a potential in reducing the negative effect of soluble NSP on cannibalism

Oligosaccharides Affect Performance and Gut Development of Broiler Chickens

The effects of oligosaccharide supplementation on the growth performance, flock uniformity and GIT development of broiler chickens were investigated. Four diets, one negative control, one positive control supplemented with zinc-bacitracin, and two test diets supplemented with mannoligosaccharide (MOS) and fructooligosaccharide (FOS), were used for the experiment. Birds given MOS or FOS had improved body weight (BW) and feed efficiency (FCR), compared to those fed the negative control diet during the 35-d trial period. The effect on FCR became less apparent when the birds got older. FOS and MOS supplementation reduced the pancreas weight as a percentage of BW, with an effect similar to that of the antibiotic, at 35 d of age. Birds given MOS tended to have a heavier bursa (p = 0.164) and lower spleen/bursa weight ratio (p = 0.102) at 35 d of age. MOS and Zn-bacitracin showed a clear improvement on flock uniformity, compared to FOS. The mortality rate was not affected by FOS or MOS

Effects of Dietary Additives and Early Feeding on Performance, Gut Development and Immune Status of Broiler Chickens Challenged with

The effects of dietary additives and holding time on resistance and resilience of broiler chickens to Clostridium perfringens challenge were investigated by offering four dietary treatments. These were a negative control (basal), a positive control (Zn-bacitracin) and two dietary additives, mannanoligosaccharides (MOS), and acidifier. Two holding times included (a) immediate access to feed and water post hatch (FED) and (b) access to both feed and water 48 h post hatch (HELD). Chicks fed Zn-bacitracin had no intestinal lesions attributed to necrotic enteritis (NE), whereas chicks fed both MOS or acidifier showed signs of NE related lesions. All dietary treatments were effective in reducing the numbers of C. perfringens in the ileum post challenge. The FED chicks had heavier body weight and numerically lower mortality. The FED chicks also showed stronger immune responses to NE challenge, showing enhanced (p<0.05) proliferation of T-cells. Early feeding of the MOS supplemented diet increased (p<0.05) IL-6 production. The relative bursa weight of the FED chicks was heavier at d 21 (p<0.05). All the additives increased the relative spleen weight of the HELD chicks at d 14 (p<0.05). The FED chicks had increased villus height and reduced crypt depth, and hence an increased villus/crypt ratio, especially in the jejunum at d 14 (p<0.05). The same was true for the HELD chicks given dietary additives (p<0.05). It may be concluded that the chicks with early access to dietary additives showed enhanced immune response and gut development, under C. perfringens challenge. The findings of this study shed light on managerial and nutritional strategies that could be used to prevent NE in the broiler industry without the use of in-feed antibiotics

Characterisation and quantification of changes in odorants from litter headspace of meat chickens fed diets varying in protein levels and additives

The effect of dietary crude protein (CP) and additives on odor flux from meat chicken litter was investigated using 180 day-old Ross 308 male chicks randomly allocated to five dietary treatments with three replicates of 12 birds each. A 5 × 3 factorial arrangement of treatments was employed. Factors were: diet (low CP, high CP, high CP+antibiotic, high CP+probiotic, high CP+saponin) and age (15, 29, 35 days). The antibiotic used was Zn bacitracin, the probiotic was a blend of three Bacillus subtilis strains and the saponin came from a blend of Yucca and Quillaja. Odorants were collected from litter headspace with a flux hood and measured using selective ion flow tube mass spectrometry (SIFT-MS). Litter moisture, water activity (Aw), and litter headspace odorant concentrations were correlated. The results showed that low CP group produced lower flux of dimethyl amine, trimethyl amine, H2S, NH3, and phenol in litter compared to high CP group (P < 0.05). Similarly, high CP+probiotic group produced lower flux of H2S (P < 0.05) and high CP+saponin group produced lower flux of trimethylamine and phenol in litter compared to high CP group (P < 0.05). The dietary treatments tended (P = 0.065) to have higher flux of methanethiol in high CP group compared to others. There was a diet × age interaction for litter flux of diacetyl, 3-hydroxy-2-butanone (acetoin), 3-methyl-1-butanol, 3-methylbutanal, ethanethiol, propionic acid, and hexane (P < 0.05). Concentrations of diacetyl, acetoin, propionic acid, and hexane in litter were higher from low CP group compared to all other treatments on d 35 (P < 0.05) but not on d 15 and 29. A high litter moisture increased water activity (P < 0.01) and favored the emissions of methyl mercaptan, hydrogen sulfide, dimethyl sulfide, ammonia, trimethyl amine, phenol, indole, and 3-methylindole over others. Thus, the low CP diet, Bacillus subtilis based probiotic and the blend of Yucca/Quillaja saponin were effective in reducing the emissions of some key odorants from meat chicken litter

Growth, Nutrient Utilisation and Gut Health of Broiler Chickens Fed Sorghum Distillers' Dried Grains with Solubles

The purpose of this thesis was to investigate the nutritional value of sorghum distillers' dried grains with solubles (sDDGS) and ways by which this can be improved. To elucidate the role of application of enzymes in diets containing sDDGS on performance, nutrient utilisation, intestinal function, gut microflora and some health related parameters, four feeding trials were conducted after a comprehensive analysis of sDDGS samples from different production batches. Each experiment has been presented as a stand-alone paper or distinct chapter

The interactive effect of dietary n-6: n-3 fatty acid ratio and vitamin E level on tissue lipid peroxidation, DNA damage in intestinal epithelial cells, and gut morphology in chickens of different ages

Feeding chickens diets high in n-3 fatty acids (FA) increases their incorporation into tissue lipids, but leads to oxidative stress in cells. This study investigated the effect of the dietary polyunsaturated FA ratio (PUFA n-6: n-3) and vitamin E (vE) level on DNA damage and morphological changes in the gut epithelium of chickens. One-day-old female broiler chicks (n = 176) were divided into 4 groups fed for 43 d diets with a high (HR) or low (LR) PUFA n-6: n-3 ratio and supplemented with 50 or 300 mg vE kg−1. Performance was calculated for periods of d 1 to 9, d 9 to 16, d 9 to 35, and d 9 to 42, while organs were sampled at d 9, d 17, d 36, and d 43. At d 17 and d 43, DNA damage of epithelial cells in the duodenum and jejunum was measured and duodenal and jejunal morphology was analyzed. HR diets improved FCR for the periods of d 1 to 9, d 9 to 16 and d 9 to 42, whereas the increased vE level improved FCR for the period of d 9 to 16. In the jejunum DNA damage was greater in chickens fed LR than HR diets at d 17 (P P P = 0.022), and mucosa thickness (P = 0.029) and villus height (P = 0.035) at d 43. The results indicated that feeding birds LR diets and vE levels significantly exceeding the recommendation induced DNA damage in epithelial cells, but this effect varied depending on the intestinal segment and the age of birds

Effect of liquid to feed ratio, steeping time and enzyme supplementation on the performance of weaner pigs

Two experiments were conducted to examine the effect of liquid to feed ratio, steeping time, and enzyme supplementation on performance of weaner pigs. In Expt 1, 40 male weaner pigs (weaned at 27 days of age) were randomly allocated to 4 treatments, including a dry control and 3 liquid diets of differing liquid: feed ratios (2 : 1, 3 : 1, and 4 : 1). Pigs were fed individually. Bodyweight was measured weekly and feed intake measured daily. The results confirmed the advantage of liquid feeding but indicated that liquid: feed ratio had very little effect on performance of weaner pigs. Whereas the digestible energy (DE) content of the 2 : 1 and 3 : 1 diets was similar to the control diet, the DE content of the 4 : 1 diet was significantly lower, possibly due to the removal of the insoluble marker (long chain hydrocarbon) by the amount of water in the diet.In Expt 2, the effect of a xylanase and steeping time on pig performance was assessed in a 2 × 2 factorial design (2 steeping times, 1 h v. 15 h; enzyme addition, + v. –). Sixty male weaner pigs (weaned at 27 days of age) were randomly allocated to 4 treatments and fed individually for 3 weeks. Bodyweight was measured weekly and feed intake measured daily. The experiment revealed that both steeping and enzyme addition increased feed intake (