Effects of dietary zinc on performance, nutrient digestibility and plasma zinc status in Cashmere goats

Thirty-six 1.0-year-old Liao Ning Cashmere goat wethers (BW = 22.01 ± 0.59 kg) were used to determine the effects of dietary zinc (Zn) level on the performance, nutrient digestibility and plasma Zn status during the cashmere fiber growing period. The goats were randomly divided into four groups that were fed a basal diet containing 22.3 mg Zn/kg dry matter (DM) with 0, 15, 30 or 45 mg Zn/kg DM as reagent grade ZnSO₄·7H₂O. The experiment lasted 60 days including a 7-day metabolism trial. Both average daily gain (ADG) and feed efficiency were improved (P < 0.05) by Zn supplementation and were higher (P < 0.05) for the treatment groups supplemented with 30 and 45 mg Zn/kg DM compared with 15 mg Zn/kg DM. Zn supplementation had no influence on the length and diameter of cashmere fiber (P > 0.05). Digestibility of DM, crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) did not differ among treatments (P > 0.05). Plasma Zn concentrations were increased (P < 0.01) by Zn supplementation and were higher (P < 0.05) for the treatment groups supplemented with 30 and 45 mg Zn/kg DM compared with 15 mg Zn/kg DM. Zn apparent absorption rate and apparent retention rate were decreased (P < 0.05) by Zn supplementation, but did not differ among Zn supplemented treatments (P > 0.05). In conclusion, a control diet containing 22.3 mg Zn/kg DM was inadequate for achieving optimal growth performance in Cashmere goats, and the recommended level of dietary Zn for such goats is 52.3 mg/kg DM during the cashmere fiber growing period.     

Effects of deoxynivalenol (DON) on growth performance, nutrient digestibility and DON metabolism in pigs

Wheat infected naturally withFusarium, contaminated mainly with 18.53 mg DON per kg, was added to a total constant wheat proportion of 400g/kg diet. Control and DON contaminated feed was fed for 11 weeks underad libitum and restrictive feeding conditions to 48 pigs of both sexes, which were randomly divided into 4 groups. Effects on performance (live weight range between 26 and 100kg), duration of feed intake and blood parameters were investigated. Parallel to this study, a balance study was carried out to examine the effects on nutrient digestibility and DON metabolism. The group fed the DON contaminated rationad libitum consumed 15% less feed and gained 14% less live weight compared to thead libitum control group, while the feed to gain ratio was unaffected. Under restrictive feeding conditions (DON and control) pigs exhibited 33%, 25% and 10% lower feed consumption, live weight gain and feed to gain ratio, respectively, than the control group fedad libitum. Metabolizability of energy, digestibility of organic matter, crude protein, crude fat and N-retention were significantly increased by 4, 3, 6, 11 and 10%, respectively, in the DON group of the restrictively fed pigs. In average up to 43.2% of the ingested DON, as the parent toxin in both groups, was eliminated with the urine and up to 3.0% with faeces. DON fed animals needed more time to consume the restrictive ration than the control group. Presented at the 26^th Mykotoxin-Workshop in Herrsching, Germany, May 17–19, 2004. Financial support Deutsone Forschungsgemeingschaft     

Using mixed silages of sweet sorghum and alfalfa in total mixed rations to improve growth performance,nutrient digestibility,carcass traits and meat quality of sheep

Combining sweet sorghum (SS) with alfalfa for ensiling has the potential to make a high-quality silage with relatively a better nutrient balance. However, the existing data are insufficient about how changes in ratios of SS to alfalfa in different silage mixtures affect animal performance and meat quality. Therefore, the objective of this study was to determine the effect of feeding total mixed rations containing mixed silages of SS and alfalfa on growth performance, nutrient digestibility, carcass traits and meat quality of Karakul sheep. Five total mixed rations were formulated with different SS proportions at 100%, 80%, 60%, 40%, and 20% on a fresh weight basis. Thirty 4-month old male Karakul sheep with 25.5 ± 1.4 kg BW were randomly allocated into five treatment groups, each with six lambs for this experiment. The results indicated that the Karakul sheep consuming total mixed rations containing SS-Alfalfa (SS-AF) silage mixtures with a lower proportion of SS tended to increase nutrient digestibility, growth performance, carcass traits, and meat quality. Feeding diets with SS at 40% and 20% inclusion rate showed a significant linear increase in the apparent digestibility of DM, CP and NDF, as well as subcutaneous fat thickness and water holding capacity (P < 0.5). Moreover, reduction in SS inclusion rate in these diets caused significant (P < 0.05) linear and quadratic increases in DM intake, final BW, average daily gain, carcass weight, and the amino acid contents of meat (P < 0.05). Conversely, feeding diet with lower SS inclusion rate led to decrease in feed conversion ratio and shear force significantly (P < 0.05) for these sheep. It appears that 40% inclusion of SS was the optimal rate in making the SS-AF silage mixture for lambs to achieve a superior production performance and high-quality meat products in Karakul sheep. However, further research is needed to investigate the effect of feeding SS-AF silage mixtures alongside contrasting ingredients on rumen function, ruminal microorganisms and digestive enzyme activity of sheep and other ruminant animals.     

Effects of dietary inclusion of Moringa oleifera leaf meal on nutrient digestibility,rumen fermentation,ruminal enzyme activities and growth performance of buffalo calves

This study was conducted to investigate the impact of dietary inclusion of Moringa oleifera leaf meal (MLM) as a substitution for soybean meal on nutrient digestibility, rumen fermentation, rumen enzyme activity, blood metabolites, growth-related hormones, and growth performance of buffalo calves. Thirty buffalo calves eight to nine months of age with an average body weight of approximately 153.7 ± 0.97 kg were randomly distributed through three dietary treatments (ten calves/treatment). MLM inclusion rates were 15% (M15) and 20% (M20), replacing soybean meal by 50 and 75% in the concentrate mixture, respectively. The results indicated that, digestibility of dry matter, organic matter (OM), and crude fiber (CF) increased significantly (p < 0.05) with MLM inclusion, while the digestibility of crude protein (CP) and ether extract (EE) reduced significantly (p < 0.05) with MLM addition. Dietary supplementation with MLM significantly affected (p < 0.001) rumen fermentation by reducing ruminal enzymes, ruminal ammonia-N, total protozoa, and acetate/propionate ratio and increasing acetic, propionic, and butyric acids and total volatile fatty acid concentrations (p < 0.001). Furthermore, dietary inclusion of 15% MLM significantly improved (p < 0.001) final body weight, dry matter intake of feed, daily weight gain, feed conversion efficiency, blood metabolites, and plasma insulin growth factor-I (IGF-I). It can be concluded that MLM is a multi-purpose protein supplement that provides some nutritional and therapeutic advantages when replacing 50% of soybean meal. Dietary supplementation of 15% MLM improved rumen fermentation, growth performance, blood metabolites, plasma IGF-I and mitigated ammonia and methane without any adverse effects in growing buffalo calves.     

Effects of extrusion of corn on growth performance,nutrient digestibility and short-chain fatty acid profiles in the hindgut of weaned piglets

Abstract

The experiment was conducted to investigate the effects of different inclusion levels of extruded corn on growth performance, nutrient digestibility and short-chain fatty acids profiles in the hindgut of weaned piglets. Ninety weaning piglets (28 d of age; 8.21 ± 0.69 kg BW) were allotted to one of five dietary treatments only substituted for unprocessed corn at varying levels (0, 1/4, 2/4, 3/4, 4/4) with extruded corn in a 28-d experiment. On day 28, 30 piglets were killed to measure concentrations and molar ratios of short-chain fatty acids in the hindgut. From day 0 – 14, digestibility of DM, N and GE was increased linearly and diarrhea frequency was decreased due to the increasing inclusion levels of extruded corn. From day 14 – 28, digestibility of GE and N was enhanced linearly due to the increasing proportion of extruded corn. On day 28, as proportion of extruded corn increased, the level of butyrate in the caecum and colon was increased linearly and the relative proportion of propionate was reduced. Results indicated that increasing proportions of extruded corn had no effect on growth performance, but significantly improved digestibility of N and energy at day 10 of trial and may be advantageous to the intestinal health of piglets.     

Effect of excessive dietary fluoride on nutrient digestibility and retention of iron, copper, zinc, and manganese in growing pigs

Ninety-six crossbred growing pigs were used to evaluate the effects of fluoride levels on growth performance, nutrient digestibility, and the retention of minerals in tissues. Four dietary treatments were formulated by supplementing fluorine (as NaF) to a corn-soybean basal diet (39.75 mg/kg F) to provide the following added fluorine levels: 0, 50 100, and 150 mg/kg fluorine. The results showed pigs of the 100 and 150 mg/kg fluorine-added groups had decreased average daily gain (ADG) and increased feed gain ratio (F/G) compared to the control (p<0.05). Apparent digestibility of protein and calcium in 100 and 150 mg/kg fluorinetreated groups was significantly lower than that of the control (p<0.05). On the other hand, iron, copper, zinc, and manganese levels in most tissues of the 100 and 150 mg/kg fluorine groups were markedly changed compared to the control (p<0.05). However, growth performance, nutrient digestibility, and mineral concentrations in all tissues of pigs were not significantly affected by the addition of 50 mg/kg fluorine (p>0.05). Thus, this study suggested that excess fluoride levels could decrease growth performance and change the retention of iron, copper, zinc, and manganese in pigs.     

Effects of feeding intact,ground and/or pelleted rapeseed on nutrient digestibility and growth performance of broiler chickens

ABSTRACT

In this study, the effect of grinding or pelleting of rapeseed on the digestibility, apparent metabolisable energy (AME_N), growth performance and gizzard weight of broiler chickens was evaluated. In Exp. 1, four treatments were tested (240 broiler chickens, 20 replications, 3 birds per cage). Birds received either a basal diet or were fed with rapeseed of different sized particles (fine, medium and coarse ground, respectively). In Exp. 2, 10 treatments were assessed (360 chickens, 12 replications, 3 birds per cage), where five different diets (a basal diet and four diets with intact rapeseed, fine ground, medium ground or coarse ground rapeseed, respectively) were fed non-pelleted or pelleted. In Exp. 3, two treatments were compared (224 broiler chickens, 14 replications, 8 birds per floor pen): fine ground rapeseed (FG) and intact rapeseed (IS). Compared with medium and coarse ground rapeseed, fine grinding increased in Exp. 1 the AME_N of rapeseed and the precaecal digestibility (PD) of dry matter and ether extract (EE) (p < 0.05). In Exp. 2, the content of AME_N and the PD of EE and crude protein (CP) increased as the degree of grinding increased when diets were not pelleted (p < 0.01). In contrast, the significantly highest values for these parameters were measured after pelleting without effect of grinding, resulting in a significant interaction between pelleting and grinding (p < 0.001). In Exp. 3, performance of chickens was not affected by dietary treatments, but gizzard weight and the PD of CP were higher when IS were included in the diet (p < 0.05). The results suggested that fine grinding may be used to increase the feeding value of full-fat rapeseed for broiler chickens. Nevertheless, pelleting of diets with rapeseed seemed to be much more effective in the reduction of particle size than grinding.     

Effect of lysophospholipids in diets differing in fat contents on growth performance,nutrient digestibility,milk composition and litter performance of lactating sows

It is well known that energy plays an important role in sow growth and development. Increasing the utilization of lipids will be beneficial to sows. Emulsifiers are substances which stabilize mixtures and prevent oil and water from separating, thereby enhancing the digestion of lipids. This study was conducted to evaluate the effect of dietary emulsifier (lysophospholipids (LPL)) supplementation in diets differing in fat contents on growth performance, nutrient digestibility and milk composition in lactating sows, as well as performance and fecal score in piglets. A total of 32 multiparous sows (Landrace×Yorkshire) were used in a 21-day experiment. On day 110 of gestation, sows were weighed and moved into the farrowing facility, randomly assigned in a 2×2 factorial arrangement according to their BW with two levels of LPL (0 and 30 mg/kg) and two levels of fat (4.75% and 2.38% fat; 13.66 and 13.24 MJ/kg). BW loss and backfat thickness loss were decreased (P<0.05) by LPL supplementation. Backfat thickness at weaning was higher (P<0.05) in sows fed LPL supplementation diets. The apparent total tract digestibility of dry matter, nitrogen, gross energy and crude fat in sows fed LPL diets was increased (P<0.05) compared with those fed non-LPL diets. Sows fed the high-fat diets had higher (P<0.05) milk fat on day 10 and milk lactose on day 20 than those fed the low-fat diets. Milk fat and lactose concentrations in LPL supplementation treatments was increased (P<0.05) compared with non-LPL treatments on day 10 and day 20, respectively. Positive interaction effects (P<0.05) between fat and LPL were observed for milk fat concentration on day 10. In conclusion, LPL addition decreased BW loss and backfat thickness loss, improved nutrient digestibility and milk fat as well as milk lactose concentrations. In addition, there was a complementary positive effect of dietary fat and LPL supplementation on milk fat concentration in lactating sows.     

Effects of konjac flour inclusion in gestation diets on the nutrient digestibility,lactation feed intake and reproductive performance of sows

This study was conducted to investigate the effects of konjac flour (KF) inclusion in gestation diets of sows on nutrients digestibility, lactation feed intake, reproductive performance of sows and preweaning performance of piglets. Two isoenergetic and isonitrogenous gestation diets were formulated: a control diet and a 2.1% KF-supplemented diet (KF diet). Both diets had the same NDF and insoluble fiber (ISF) levels, but the KF diet had higher soluble fiber (SF) level. The day after breeding, 96 multiparous sows were assigned to the two dietary treatments. Restrict-fed during gestation, in contrast, all sows were offered the same lactation diet ad libitum. Response criteria included sow BW, backfat depth, lactation feed intake, weaning-to-estrus interval, litter size and piglet’s weight at parturition and day 21 of lactation. On day 60 of gestation, 20 sows were used to measure nutrient digestibility. Results showed that the digestibility of dry matter, gross energy, crude fiber and ADF were not affected by the dietary treatments. The inclusion of KF in gestation diets increased NDF digestibility (P<0.05) and tended to increase the digestibility of CP (P=0.05) compared with the control diet group. In addition, dietary treatment during gestation did not affect litter size, BW and backfat gain during gestation, lactation weight, backfat loss or weaning-to-estrus interval of sows. However, sows fed the KF diet consumed more (P<0.05) lactation diet per day than sows in the control group. Accordingly, sows fed the KF diet showed greater average piglet weights on day 21 of lactation (P=0.09), and the litter weight of sows fed the KF diet on day 21 of lactation increased by 3.95 kg compared with sows fed the control diet (not significant). In conclusion, the inclusion of KF in gestation diets increased lactation feed intake of sows and tended to improve litter performance.     

Effects of water restriction on growth performance,feed nutrient digestibility,carcass and meat traits of rabbits

The study investigates the effects of a post-weaning water restriction on performance, nutrient digestibility, carcass traits and meat quality of 84-day-old rabbits. A total of 1388 weaned rabbits (35 days) were randomly divided into two groups on the basis of BW and sex. The two groups were fed the same diets ad libitum both in the post-weaning (35 to 60 days) and fattening (61 to 84 days) periods. In the post-weaning period, one group (AL) also received drinking water ad libitum, whereas the other (WR) had a water restriction from 35 to 41 days 2 h/day; from 42 to 48 days 2.5 h/day; from 49 to 55 days 3 h/day; and from 56 to 60 days 4 h/day. During the fattening period, both groups had water-free access. Individual live weights and feed intake per cage were recorded weekly for 32 cages randomly chosen per group (64 rabbits) to calculate the BW gain, feed intake and feed conversion ratio (FCR). The apparent digestibility values of nutrients were measured using acid-insoluble ash. Carcass data were collected from 16 rabbits (8 males and 8 females) per group selected for similar final BW in both groups. Mortality from 35 to 60 days was higher in the AL group (10.1% v. 5.2%, for AL and WR, respectively, P < 0.0001). BW gain was higher for the AL group during both the post-weaning (+22.4%, P < 0.01) and the entire period (+7.5%, P < 0.05). Water restriction reduced feed intake both in the post-weaning (−17.4%, P < 0.0001) and in the entire period (−9.9%, P < 0.05). During the fattening period, FCR was lower for the WR group (5.15 v. 5.75 g/g, for WR and AL, respectively, P < 0.05). The apparent digestibilities of dry matter, organic matter, NDF, ADF and cellulose were greater in the restricted rabbits (+4.7%, +4.5%, +10.2%, +18.8% and +12.8%, P < 0.01, P < 0.01, P < 0.05, P < 0.01, P < 0.05, respectively). Perirenal and scapular fat percentages were higher in the AL rabbits (+30.7% and +116.6%, P < 0.01 and P < 0.001, respectively). Water restriction increased saturated fatty acids (C16:0, +12.9%, P < 0.05), lauroleic acid (C12:1, +75.0%, P < 0.01), n-3 polyunsaturated fatty acids (C20:5, +50.0%, P < 0.01 and C22:5, +16.6%, P < 0.05) and the n-3/n-6 ratio (+28.6%, P < 0.05). The applied water restriction between 35 and 60 days executed during the winter months improved the digestive health of rabbits, with no negative effects on carcass traits, or physical and chemical meat characteristics. However, from the animal welfare point of view, a water restriction can be criticized as a method to restrict feed intake.     

Effects of temporary intensive feed restriction on performance,nutrient digestibility and carcass criteria of growing male Californian rabbits

The aim of the study was to evaluate the effect of a temporary quantitative feed restriction on growth performance, nutrient digestibility and carcass criteria of rabbits. A total of 80 weaned male Californian rabbits (30 d of age) were randomly assigned to four treatments of 20 rabbits each. The Control group was fed ad libitum during the whole experimental period (days 30–72 of age). For the three restricted fed groups the feed intake was reduced by 15%, 30% and 45% compared to the Control group, respectively. The feed restriction was applied after weaning and lasted for 21 d. Thereafter, at 51 d of age, in all treatments the feed supply returned to ad libitum intake till 72 d of age (AL period). The feed restriction decreased the body weight gain of rabbits (during the restriction period and the whole experimental period, p < 0.001) and improved feed conversion ratio during all tested periods (p < 0.001). In the AL period, the daily body weight gain of all groups was similar. After the AL period, the digestibility of all measured nutrients was significantly higher for animals fed restrictively. Furthermore, feed restrictions significantly decreased the proportion of perirenal and scapular fat and increased relative weight and length of the gastrointestinal tract. Therefore, it can be concluded that the applied feed restriction improved feed conversion, nutrient digestibility and reduced fat at the slaughter age of Californian rabbits, but the reduced body weight gain could not be compensated by a subsequent ad libitum feeding for 3 weeks.     

The influence of ergot-contaminated feed on growth and slaughtering performance,nutrient digestibility and carry over of ergot alkaloids in growing-finishing pigs

Abstract

Diets containing 0, 1 and 10 g ergot (Claviceps purpurea) per kg, corresponding to mean total alkaloid contents of 0.05, 0.60 and 4.66 mg/kg (sums of ergometrine, ergotamine, ergocornine, α-ergocryptine, ergocristine, ergosine and their -inine isomers analysed by a HPLC-method), were each fed ad libitum to 12 pigs in the BW range of 30–115 kg to study the effect of ergot-contaminated feed on growth and slaughtering performance and the carry over of ergot alkaloids. Additionally, balance trials were conducted to investigate the digestibility of nutrients. Tendencies towards reduced feed intake and BWG were observed at a feeding level of 4.66 mg total alkaloids per kg diet. Typical symptoms of ergot poisoning were not observed. Heart and spleen weights showed significant linear increases. Differences in carcass quality due to dietary treatment were not detected. No genuine ergot alkaloids were found in physiological samples. The balance trials demonstrated a significantly decreased protein digestibility for the most highly supplemented diet.     

Investigation on the precaecal and faecal digestibility of lactulose and inulin and their influence on nutrient digestibility and microbial characteristics

This study was conducted to determine the pre-caecal and faecal digestibility of lactulose and inulin and the influence of these substances on nutrient digestibility and microbial characteristics. In metabolic trials three of six male growing pigs (German Landrace?×?Pietrain) were fitted with an ileo-rectal anastomosis (IRA) in end-to-end technique with preserved ileo-caeco-colic valve. The metabolic trials were conducted from day 21?–?63 after surgery. The remaining pigs were used as intact partners (IN) for the IRA pigs. The experimental diets, based on corn, wheat, barley and soybean meal, were supplemented with either 1.5% lactulose or 2% inulin in replacement of diatomaceous earth (control). Pre-caecal digestibility of lactulose and inulin was assessed to be 79 and 98%, respectively, faecal digestibility was determined as 100%. The supplementation of lactulose and inulin had only minor effects on the pre-caecal and faecal digestibility of nutrients. Significant differences in nutrient digestibility were obvious between IRA and IN pigs, whereas the IRA pigs showed lower digestibility values with the exception of ether extracts (EE). Bacterial population in the digesta of IRA and IN pigs were not affected by the experimental diets except the concentration of gram-negative anaerobes, which inclined when the IRA pigs received the lactulose diet. The pH of chyme was significantly lower than the pH of faeces, however the pH was unaffected by the different supplemented diets. The concentration of volatile fatty acids (VFA) in pre-caecal chyme decreased significantly when IRA pigs received the lactulose supplemented diet whereas VFA in faeces were unaffected by the supplementation. IRA pigs administered with lactulose excreted more N via the urine, but the nitrogen balance remained unaffected. From the present investigation it can be concluded that lactulose and inulin did only partly or scarcely fulfill the expectation of acting as prebiotics in pigs.     

Effects of dietary cellulase and xylanase addition on digestion,rumen fermentation and methane emission in growing goats

The objective of this study was to evaluate the effectiveness of supplementation of cellulase and xylanase to diets of growing goats to improve nutrient digestibility, utilisation of energy and mitigation of enteric methane emissions. The experiment was conducted in a 5 × 5 Latin square design using five goats with permanent rumen fistulae and five treatments consisted of two levels of cellulase crossed over with two levels of xylanase plus unsupplemented Control. The cellulase (243 U/g) derived from Neocallimastix patriciarum was added at 0.8 and 1.6 g/kg dry matter intake (DMI) and the xylanase (31,457 U/ml) derived from Aspergillus oryzae was fed at 1.4 and 2.2 ml/kg DMI. There were no differences in apparent digestibility of organic matter, neutral detergent fibre, acid detergent fibre and rumen fermentation parameters (i.e. ammonia-nitrogen [N], volatile fatty acids) among all treatments. Dietary cellulase and xylanase addition did not influence energy and N utilisation. But compared to xylanase addition at the higher dose, at the low xylanase dose the retained N, the availability of retained N and digested N were increased (p < 0.01). Moreover, enzyme addition did not affect the enteric methane emission and community diversity of ruminal methanogens. The present results indicated that previous in vitro findings were not confirmed in ruminant trials.     

Effects of dietary addition of cellulase and a Saccharomyces cerevisiae fermentation product on nutrient digestibility,rumen fermentation and enteric methane emissions in growing goats

This study was designed to assess the effectiveness of dietary cellulase (243 U/g, derived from Neocallimastix patriciarum) and a Saccharomyces cerevisiae fermentation product (yeast product) on ruminal fermentation characteristics, enteric methane (CH₄) emissions and methanogenic community in growing goats. The experiment was conducted in a 5 × 5 Latin square design using five Xiangdong black wether goats. The treatments included a Control and two levels of cellulase (0.8 g and 1.6 g/kg dry matter intake (DMI), i.e. 194 U/kg and 389 U/kg DMI, respectively) crossed over with two levels (6 g or 12 g/kg DMI) of the yeast product. There were no significant differences regarding feed intake, apparent digestibility of organic matter, neutral detergent fibre and acid detergent fibre among all the treatments. In comparison with the Control, the ruminal ammonia N concentration was decreased (p = 0.001) by cellulase and yeast product addition. The activities of carboxymethylcellulase and xylanase were decreased after cellulase addition. Moreover, dietary cellulase and yeast product addition led to a significant reduction (p < 0.05) of enteric CH₄ emissions although the diversity and copy numbers of methanogens among treatments were not dissimilar. The present results indicate that the combination of cellulase and yeast fermentation product can reduce the production of CH₄ energy and mitigate the enteric CH₄ emissions to a certain degree.     

Effects of graded dose dietary supplementation of Piper betle leaf meal and Persicaria odorata leaf meal on growth performance,apparent ileal digestibility,and gut morphology in broilers

Due to antimicrobial resistance and the public health hazard of antibiotic growth promoters, there is a grave need to find potential alternatives for sustainable poultry production. Piper betle (PB) and Persicaria odorata (PO) are herbs, which have been reported for antimicrobial, antioxidant, and anti-inflammatory properties. The present study aimed to estimate the influence of different dose supplementation of Piper betle leaf meal (PBLM) and Persicaria odorata leaf meal (POLM) on growth performance, ileal digestibility and gut morphology of broilers chickens. A total of 210 one day-old broiler chicks were randomly grouped into 7 treatments, and each treatment group has 3 replicates (n = 10) with a total number of 30 chicks. The treatments included T₁ control (basal diet (BD) with no supplementation), T₂ (BD + 2 g/kg PBLM); T₃ (BD + 4 g/kg PBLM), T₄ (BD + 8 g/kg PBLM), T₅ (BD + 2 g/kg POLM), T₆ (BD + 4 g/kg POLM), T₇ (BD + 8 g/kg POLM). Growth performance, gut morphology and ileal digestibility were measured. Except for T₄ (8 g/kg PBLM), graded dose inclusion of PBLM and POLM increased (P < 0.05) the body weight gain (BWG), positively modulated the gut architecture and enhanced nutrient digestibility in both stater and finisher growth phases of broiler chickens. Birds fed on PBLM 4 g/kg (T₃), and POLM 8 g/kg (T₇) had significantly higher (P < 0.05) BWG with superior (P < 0.05) feed efficiency in the overall growth period. Chickens fed on diets T₃ and T₇ had longer (P < 0.05) villi for duodenum as well as for jejunum. Furthermore, the birds fed on supplementations T₃ and T₇ showed improved (P < 0.05) digestibility of ether extract (EE), and dry matter (DM) compared to the control group. However, least (P < 0.05) crude protein (CP) digestibility was recorded for T_4. In conclusion, dietary supplementations of PBLM 4 g/kg and POLM 8 g/kg were positively modulated the intestinal microarchitecture with enhanced nutrient digestibility, resulted in maximum body weight gain, thus improved the growth performance of broiler chickens.     

The effects of supplementing varying molecular weights of chitooligosaccharide on performance,selected microbial populations and nutrient digestibility in the weaned pig

An experiment (complete randomised design) was conducted to investigate the effects of supplementing different molecular weights (MW) of chitooligosaccharide (COS) on pig performance, selected microbial populations and nutrient digestibility post-weaning. A total of 396 weaned piglets (24 days of age, 7.3 kg ± (s.d.) 1.7 kg live weight) were assigned to one of six dietary treatments (22 replicates/treatment) for a 33-day experimental period. The dietary treatments were as follows (1) control diet (0 ppm COS), (2) control diet plus <1 kDa COS, (3) control diet plus 3 to 5 kDa COS, (4) control diet plus 5 to 10 kDa COS, (5) control diet plus 10 to 50 kDa COS and (6) control diet plus 50 to 100 kDa COS. The COS were included at 250 ppm in the diets. There was no significant effect of dietary treatment on piglet performance during the starter period (days 0 to 18; P > 0.05). However, there were quadratic responses in both daily gain (P < 0.05) and gain to feed ratio (P < 0.05) to the increased MW of COS inclusion during the weaner period (days 18 to 33) with all COS-supplemented treatments improving daily gain and gain to feed ratio compared with the control. There was a quadratic response in faecal scoring to the increased MW of COS inclusion from days 0 to 7 (P < 0.001), days 7 to 14 (P < 0.001) and during the overall experimental period (P < 0.01) with all the COS-supplemented treatments having an improved faecal score compared with the control. During the weaner period, there was a cubic response in lactic acid bacteria and Escherichia coli populations as the MW of COS increased (P < 0.05). The 5 to 10 kDa and 10 to 50 kDa COS increased lactic acid bacteria populations compared with the control, whereas lactic acid bacteria populations decreased at 50 to 100 kDa. The 5 to 10 kDa, 10 to 50 kDa and 50 to 100 kDa COS decreased E. coli populations compared with the control. There was a cubic response in the apparent total tract digestibility of dry matter (DM; P < 0.01), organic matter (OM; P < 0.01), ash (P < 0.01), nitrogen (N; P < 0.01) and gross energy (GE; P < 0.01) to the increased MW of COS inclusion during the weaner period. The 5 to 10 kDa COS had a higher apparent total tract digestibility of DM, OM, ash, N and GE in comparison to the control, whereas the apparent total tract nutrient digestibility of these nutrients decreased at 10 to 50 kDa. The current results indicate that the MW ranges of 5 to 10 kDa and 10 to 50 kDa COS decreased E. coli numbers while increasing nutrient digestibility of the diets.     

Effects of folic acid on growth performance,ruminal fermentation,nutrient digestibility and urinary excretion of purine derivatives in post-weaned dairy calves

This study evaluated the effects of folic acid (FA) supplementation on growth performance, ruminal fermentation, nutrient digestibility and urinary purine derivatives (PD) excretion in dairy calves. Forty-eight Chinese Holstein male dairy calves at 60 ± 3.2 d of age and 89 ± 5.9 kg body weight (mean ± standard error) were assigned to one of four groups in a randomised block design. Calves in control group were fed basal diet, calves in low FA, medium FA and high FA groups with 3.6, 7.2 and 10.8 mg FA per kg basal diet, respectively. The dietary corn silage to concentrate ratio was 50:50 (dry matter [DM] basis). DM intake and average daily gain (ADG) quadratically increased, and feed conversion ratio quadratically decreased with increasing FA supplementation. Ruminal pH linearly decreased, whereas total volatile fatty acids quadratically increased. The unchanged acetate-to-propionate ratio was due to the similar change in acetate and propionate concentration. Ammonia N content quadratically decreased. Digestibility of DM, organic matter, crude protein, ether extract, neutral detergent fibre and acid detergent fibre linearly increased. Activities of carboxymethyl cellulase, cellobiase, xylanase and pectinase linearly increased, but α-amylase and protease quadratically increased. Abundance of Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes linearly increased, but Butyrivibrio fibrisolvens and Prevotella ruminicola quadratically increased. Urinary total PD excretion quadratically increased. The results indicated that FA supplementation increased ADG, ruminal fermentation and nutrient digestibility with promoted ruminal microbial growth and enzyme activity, and the optimum dose was 7.2 mg FA per kg basal diet for calves.     

Influence of source and micronization of soya bean meal on growth performance,nutrient digestibility and ileal mucosal morphology of Iberian piglets

The effects of inclusion in the diet of different sources of soya bean meal (SBM) on growth performance, total tract apparent digestibility (TTAD) and apparent ileal digestibility (AID) of major dietary components and mucosal ileum morphology were studied in Iberian pigs weaned at 30 days of age. From 30 to 51 days of age (phase I), there was a control diet based on regular soya bean meal (R-SBM; 44% CP) of Argentina (ARG) origin and five extra diets in which a high-protein soya bean meal (HP-SBM; 49% CP) of the USA or ARG origin, either ground (990 μm) or micronized (60 μm), or a soya protein concentrate (SPC; 65% CP) substituted the R-SBM. From 51 to 61 days of age (phase II), all pigs were fed a common commercial diet in mash form. The following pre-planned orthogonal contrasts were conducted: (1) R-SBM v. all the other diets, (2) SPC v. all the HP-SBM diets, (3) micronized HP-SBM v. ground HP-SBM, (4) HP-SBM of ARG origin v. HP-SBM of US origin and (5) interaction between source and the degree of grinding of the HP-SBM. Dietary treatment did not affect growth performance of the pigs at any age but from 30 to 51 days of age, post weaning diarrhoea (PWD) was higher (P<0.001) and the TTAD and AID of all nutrients were lower for pigs fed the R-SBM diet than for pigs fed the HP-SBM or the SPC diets. However, no differences between the HP-SBM and the SPC containing diets were detected for any trait. The TTAD of organic matter (P=0.07) and gross energy (GE) (P=0.05) tended to be higher for the micronized HP-SBM than for the ground HP-SBM and that of GE was higher (P<0.05) for US meal than for the ARG meal. Pigs fed R-SBM had lower villus height (P<0.01) than pigs fed HP-SBM or SPC but no differences in ileal mucosal morphology were detected between SPC and HP-SBM containing diets. It is concluded that feeding the HP-SBM or SPC-reduced PWD and improved nutrient digestibility and ileal morphology as compared with feeding the R-SBM, but had no effect on pig performance. The inclusion in the diet of added value soya products (micronized SBM or SPC) in substitution of the R-SBM increased the TTAD of all nutrients and reduced PWD but had no advantage in terms of growth performance over the use of ground HP-SBM.     

Effects of dietary supplementation with freshwater microalgae on growth performance,nutrient digestibility and gut health in weaned piglets

In pigs, digestive disorders associated with weaning lead to antibiotic use to maintain intestinal health. Microalgae have been studied in humans and rodents for their beneficial effects on health. The nutritional value of microalgae in animal diets has been assessed, but results were not conclusive. Dietary supplementation with microalgae as an alternative to antibiotic use was studied in two trials (72 piglets with initial BW=9.1±1.1 kg in trial 1 and 24 piglets with initial BW=9.1±0.9 kg in trial 2). All piglets were weaned at 28 days of age and then housed in individual cages. Piglets were randomly allocated to one of the four diets during 2 weeks after weaning: a standard diet with no supplementation (NC) or the standard diet supplemented with 1% Spirulina (SP), with 1% Chlorella (CV), or with 0.2% of colistin as positive control (PC). Trial 1 was performed to determine the effect of microalgae supplementation from 28 to 42 days on performance and incidence of diarrhoea. Animals received then a standard diet from 42 to 56 days of age. Trial 2 was performed from 28 to 42 days of age to assess nutrient digestibility of the experimental diets and to determine inflammatory status and intestinal morphology at 42 days of age. In trial 1, 94% of the pigs had diarrhoea in the 1st week after weaning with no beneficial effect of colistin on diarrhoea incidence, average daily feed intake (ADFI), average daily gain (ADG), and gain : feed (G : F) ratio. This suggests that the diarrhoea was due to digestive disorders that did not result from enterotoxigenic Escherichia coli infection. Supplementation with either Spirulina or Chlorella did not affect ADFI, ADG and G : F in trials 1 and 2 (P>0.10). Diarrhoea incidence was reduced in CV pigs compared with NC, SP and PC pigs (P<0.05). Total tract digestibility in pig receiving microalgae was greater for gross energy (P<0.05), and tended to be greater for dry matter, organic matter and NDF (P<0.10) compared with NC and PC pigs. Villus height at the jejunum was greater in SP and CV pigs compared with NC and PC pigs (P<0.05). This study shows a potential effect of both Spirulina and Chlorella supplementation on intestinal development and a potential of Chlorella supplementation to manage mild digestive disorders. Further investigation is necessary to determine the mechanism action of Spirulina and Chlorella on gut health and physiology.