This trial was conducted to study the effect of full-fat rice bran inclusion in diets on growth performance, carcass and meat quality and fatty acid composition in Sichuan goose.
A total of 204 Sichuan white male geese (28-d-old, 984 ± 15 g) were used in the 42-d assay. Full-fat rice bran inclusion in diets was 0%, 6%, 12% and 18%, respectively.
On d 70, two geese from each pen were randomly selected and killed for measuring the carcass and meat quality and the meat fatty acid composition.
The results showed that full-fat rice bran inclusion had no effect on average daily gain during 28–56 d, but rice bran inclusion at 18% increased average daily gain during 57–70 d. In addition, the full-fat rice bran supplementation decreased the subcutaneous fat yield, and the inclusion of full-fat rice bran in amounts of 12% and 18% decreased the half-eviscerated carcass yield, eviscerated carcass yield and crude fat content in goose meat. Moreover, full-fat rice bran supplementation had no effect on the content of total saturated fatty acid (SFA), but decreased the content of total monounsaturated fatty acid (MUFA). The inclusion of full-fat rice bran in amounts of 12–18% increased the content of total polyunsaturated fatty acid (PUFA) and total n-6 in goose meat and in the amount of 18% increased n-3 fatty acids content in goose meat.
The results indicated that the rice bran inclusion had a positive effect in geese by stimulating growth performance and improving meat quality and fatty acid composition of goose meat.
This study aimed to evaluate the influence of an organic acid (OA) and essential oil (EO) blends, individually or in combination, on growth performance, carcass parameters, apparent digestibility, intestinal microflora and intestinal morphology of broilers.
A total of 480 one-d-old male Ross 308 chicks were randomly assigned to 4 treatments consisting of 4 replicates each (n = 30 birds in each replicate). Dietary treatments consisted of a basal diet (control), and basal diet supplemented with 2 g/kg OA blend (OAB), 300 mg/kg EO blend (EOB), or with 2 g/kg OA and 300 mg/kg EO blend (OAB–EOB) for 42 d.
The dietary supplementation with EO blend or in combination with OA blend increased body weight gain and improved feed efficiency as compared to control. Dietary treatments had no significant effects on feed consumption or relative organ weights of broilers.
The OAB diet increased carcass yield compared to the control diet but the lowest carcass yield occurred with the OAB–EOB combination. Birds fed on EOB and OAB–EOB diets had lower ileum Escherichia coli counts than birds fed on the control diet.
There was no significant effect of treatments on apparent digestibility at 16–21 d but the EOB and OAB–EOB diets increased apparent digestibility of dry matter and crude protein during the finisher period (d 37–42) compared to the control diet.
Birds fed on the EOB and OAB–EOB diets had greater villus height in the ileum at 21 and 42 d of age and had lower crypt depth in the ileum at 42 d of age than birds given the control diet.
In conclusion, beneficial effects of the use of EO blend individually or in combination with the OA blend were observed but the OA blend alone was ineffective. Furthermore, the use of the combination of OA and EO was more effective, in some respects, than their individual use.
The aim of this study was to increase the content of n-3 fatty acids (FA) of meat without affecting its sensory and/or technological properties or the growth performance of chickens reared under standard conditions. Male chickens, Ross 308, were distributed into 5 groups corresponding to 5 different diets for the growing and finishing periods: control (T), containing extruded linseeds exhibiting high concentration of fibre (ELHF), extruded linseeds exhibiting low concentration of fibre (ELLF), microalgae, or an association of 75% ELLF and 25% MA (ELLF+MA).
The diet containing microalgae induced a decrease in feed consumption without affecting growth rate. Chickens exhibited a lower feed conversion ratio than the other groups for the growing and finishing periods but also the whole rearing period. The use of linseeds in diets had no effect on the growth performance of chickens in comparison to the control group.
The dietary enrichment with n-3 FA had few effects on carcass composition or the ultimate pH and colour of breast meat. The microalgae increased the meat susceptibility to oxidation. The lipid content of breast meat was not affected by the diets. The breast meat of chickens fed on diets containing linseeds and/or microalgae had greater n-3 FA content (2.4 to 3.9 times higher than group T). The linseeds and microalgae mainly increased the contents in linolenic acid and long chain n-3 FA, respectively.
Dietary enrichment with n-3 FA had no effect on the sensory quality of fillets whereas the thighs of the MA group exhibited the lowest score for the flavour “chicken” and the greatest score for the flavour “abnormal” corresponding to a fish flavour.
Three experiments with a 2 × 2 × 2 factorial arrangement were conducted to evaluate maize-based diets for broilers containing different lipid sources [soybean oil (S) or beef tallow (T)] supplemented with or without lysophospholipids and organic acids on nutrient balance (Experiment I, evaluation period of 10–14 d), on liver concentration of fat-soluble vitamins, on jejunal microbiota (Experiment II, sampling at d 14) and on performance (Experiment III, accumulated periods of 1–14, 1–21 and 1–42 d).
A total of 1344 male chicks were used. In each experiment, the birds were allotted in a completely randomised design with 8 replications. The lysophospholipids were mainly composed of lysolecithins and the organic acids blend was constituted by lactic (40%), acetic (7%) and butyric acids (1%).
An interaction between lipid sources and lysophospholipids was observed on faecal apparent digestibility of lipid (ADL), which improved with lysophospholipids addition in T diets. Broilers fed on S had higher ADL and faecal apparent digestibility of nitrogen-corrected gross energy (ADGEN).
It was not possible to demonstrate a significant treatment effect on the liver concentration of vitamins A and E, even with the differences in fatty acid profile between S and T.
Enterobacteria values were below the detection threshold. Lysophospholipid supplementation reduced gram-positive cocci in T-fed birds. S diets promoted lower total anaerobe counts compared with T diets, independent of additives.
S diets increased BW gain and feed:gain ratio in all evaluation periods. Lysophospholipids and organic acids improved feed:gain ratio at 1–21 d in T diets. Furthermore, main effects were observed for lysophospholipids and organic acids at 1–42 d, which increased BW gain and improved feed:gain ratio, respectively.
No positive interactions between additives were found.
A 4 × 2 factorial experiment was conducted to study the effect of feeding diets-containing dietary fibre (DF) sources and a source of bile acid (BA) on growth performance and lipid metabolism. In addition, in vitro BA-binding capacity of fibre sources was investigated.
A total of 256 one-d-old male broiler chickens (Ross 308) were assigned to DF sources [maize-soybean meal (control, C), or 30 g/kg of wheat bran (WB), barley bran (BB) or soybean hulls (SH)] and BA (with or without 1.5 g Na-deoxycholate/kg). Each treatment was replicated 4 times with 8 broiler chickens per cage.
The highest in vitro BA-binding capacity was observed with BB (8.76 mg/g BB). From 0 to 21 d, with the addition of BA, the average daily feed intake (ADFI) decreased in broiler chickens fed on the C, WB or BB diets, while there was no difference with the SH diet. With added BA, the average daily gain decreased in broiler chickens fed on the C or SH diets, but it did not change in those fed on the other diets. The addition of BA decreased feed conversion ratio (FCR) in broiler chickens fed on the BB or WB diets, but it increased in those fed on the C or SH diets. Interaction results indicated that the apparent ileal digestibility of lipid increased in broiler chickens fed the C and other DF diets with BA compared to those fed the diets without BA. The addition of BA decreased the pancreas lipase activity (PLA) in broiler chickens fed on the C diet compared to those fed the C diet without BA, while no changes observed in those fed the DF diets with or without BA. No interaction was observed in total liver bile acid (TLBA).
The WB, BB and SH with little Na-deoxycholate-binding capacity (<10 mg/g of DF) under in vitro conditions had particular effects with BA on the measured criteria in broiler chickens. The magnitude of improvement in digestibility of lipid with the addition of BA depends on the source of fibre used and the addition of BA in DF diets had little effect on growth performance in young broiler chicken diets.
The effects of 5 different feeding systems on the performance, carcass traits and organ development were studied in pigeon squabs.
The 5 treatments were (1) whole grains of maize, pea and wheat plus concentrate feed; (2)whole grains of maize and wheat plus concentrate feed (CWC); (3) whole grains of maize and pea plus concentrate feed; (4)whole grain of maize plus concentrate feed (CC); and (5) compound feed (CF).
Feed intake of parent pigeons increased significantly from 0 to 21 d and it was higher in the CF treatment. Body weight of squabs in the CWC treatment was the highest among the 5 treatments in 4 weeks. Body weight losses of parental pigeons during the rearing period were not significantly different among the 5 treatments.
Protein intake in CC and CWC treatments was lower than that of the other three treatments. The CWC treatment had the highest daily weight gain and the lowest feed conversion ratio. Treatments were statistically similar in the relative weight of carcass, breast and thigh. CF had the lower relative weight of abdominal fat.
Relative weight of gizzard in the CF treatment was significantly lower than that of CWC.
It was concluded that the application of free choice feeding of whole grains of maize and wheat plus concentrate feed increased the body weight of 28-d-old pigeon squabs and decreased the feed conversion rate of parent pigeons. This feeding strategy could be commercially interesting in meat-type pigeon production.
The effects of high dose of microbial phytase and an emulsifier on the performance, apparent metabolisable energy (AME) and nitrogen (N) retention in broilers fed on diets containing different fat sources were examined in a 5-week trial. Two fat sources (soy oil and tallow), two inclusion levels of E. coli phytase (500 or 1000 phytase units (FTU)/kg diet) and two inclusion levels of lysolecithin emulsifier (0 or 3.5 g/kg of diet) were evaluated in a 2 × 2 × 2 factorial arrangement of treatments.
Throughout the 5-week trial, soy oil supplementation improved weight gain and feed per gain compared with tallow, but had no effect on feed intake.
The high dose of phytase increased the weight gain and feed intake and lowered the feed per gain during d 1–21, but had no effect on performance parameters over the whole trial period.
An effect of emulsifier was observed for feed intake during d 1–21 and over the whole trial period. Addition of emulsifier increased feed intake compared with diets without emulsifier.
During weeks 1, 2, 3 and 5, birds fed on soy oil–based diets had higher nitrogen-corrected AME (AMEN) compared with those fed on tallow-based diets. During weeks 2, 3 and 5, the effect of phytase was significant for AMEN, with the high dose increasing the AMEN. During week 2, AMEN was increased with emulsifier addition.
During weeks 1, 2, 3 and 5, birds fed on soy oil–based diets had higher fat retention compared with those fed on tallow-based diets. The high dose of phytase improved the retention of fat during week 5 and the addition of emulsifier resulted in higher fat retention during week 1.
During weeks 2, 3 and 5, an interaction between fat source × phytase × emulsifier was observed for N retention. In soy oil–based diets, emulsifier plus 1000 FTU/kg phytase increased N retention compared with other groups, while in tallow-based diets, emulsifier addition increased N retention in diets with 500 FTU/kg, but not in 1000 FTU/kg diet.
Overall, the present data suggest that the dietary fat source influenced performance, AMEN and fat retention in broiler chickens. There is opportunity to improve bird performance during d 1–21, AMEN and fat retention with higher doses of microbial phytase. Addition of the emulsifier increased the AMEN during week 2 and tract retention of fat during week 1, but this effect was not translated into improvements in performance.
This study evaluated the growth performance and meat characteristics of grower geese whose diets included garlic scape meal (GSM), a by-product of garlic production. Scape is the leaf-less flower stem of garlic.
Garlic scape (GS) extracts contained 84.7 ± 3.8 μg/g dry weight (DW), 81.4 ± 8.2 μg/g DW, 0.78 ± 0.05 mg gallic acid equivalent/g DW and 31.67 ± 2.25 μg/g DW of allicin, alliin, total phenolics and flavonoid contents, respectively.
In total, 120 White Roman geese aged 5 weeks were randomly distributed among 12 pens and fed on a grower diet ad libitum during the growth period. Employing a completely random design, 5 males and 5 females were placed in each pen.
Each treatment was applied to three pens (in total 30 birds) and the treatments comprised the following: 1) control (maize–soybean meal), 2) 5% of maize replaced with 5% of GSM (5% GSM), 3) 10% of maize replaced with 10% of GSM (10% GSM) and 4) 15% of maize replaced with 15% of GSM (15% GSM). Each group of 30 birds was treated for 8 weeks.
The results revealed that the 15% GSM group was characterised by a lower feed conversion ratio than the control group; however, these groups did not differ significantly in their body weights (BWs). In addition, the 10% GSM group did not differ in both the feed conversion ratio and consumption.
The flavour intensity score of meats in the 10% GSM group was significantly lower than those of meats in the 5% GSM and control groups. The general acceptability scores of meats in the 5% GSM and control groups were higher than those of meat in the 10% GSM group.
The study concluded that 5% dietary GSM in the feed did not adversely affect the growth performance, meat characteristics or sensory evaluation of grower geese. Hence, the environment can be protected by including agricultural waste in goose diets.
This study had the aim of evaluating the effects of medium-chain fatty acids (MCFA) on performance, carcass characteristics, some blood parameters and antibody titre against sheep red blood cells (SRBC) in quail.
A total of 240 quail chicks were allotted to 4 treatments consisting of respectively 0, 1, 2 and 4 g/kg dietary MCFA.
There were no significant differences in body weight, feed intake and feed conversion ratio among treatments at different stages of the experiment.
MCFAs had no significant effect on breast, thigh, liver, spleen and bursa of Fabricius weight ratios. However, the relative weight of abdominal fat significantly decreased in quail receiving 0.2 and 0.4 MCFA as compared to other treatments.
Concentrations of low-density lipoprotein-cholesterol (LDL), triglycerides and total cholesterol were decreased and high-density lipoprotein (HDL)-cholesterol was increased in quail chicks receiving MCFA compared with control quail chicks. The concentrations of SRBC antibody were not statistically different among treatments.
It is concluded that MCFA significantly decreased LDL, triglycerides, cholesterol and abdominal fat and increased HDL in quail chicks.
Two experiments were carried out in parallel with male Ross 308 broilers over 37 d. An experiment with a total of 736 broilers was performed to study the effect of dietary inclusion of crimped kernel maize silage (CKMS) on broiler production and meat quality. Another study with 32 broilers was carried out from 21 to 25 d to investigate the inclusion of CKMS on nutrient digestibility.
In both trials, 4 dietary treatments were used: wheat-based feed (WBF), maize-based feed (MBF), maize-based feed supplemented with 15% CKMS (CKMS-15) and maize-based feed supplemented with 30% CKMS (CKMS-30).
Compared with MBF, the dry matter (DM) intakes of broilers receiving CKMS-15 and CKMS-30, respectively, were numerically 7.5 and 6.2% higher and feed conversion ratio 6 and 12% poorer (significant for 30% CKMS), although there were no significant differences in AME content between the three diets. At 37 d, the body weight of birds receiving 15% CKMS was similar to birds fed with MBF. However, the inclusion of 30% CKMS decreased broiler growth. Dietary supplementation with CKMS significantly reduced the apparent digestibility of phosphorus. The fat digestibility was significantly lower for CKMS-30 than for the other three diets.
Broiler mortality decreased significantly when CKMS was added to the diet.
The consumption of drinking water was significantly lower in all maize-based diets as compared to WBF and was lowest in broilers fed with CKMS-30.
An improved litter quality in terms of DM content and a lower frequency of foot pad lesions was observed with broilers supplemented with both dietary levels of CKMS.
The addition of CKMS to maize-based diets increased juiciness, tenderness and crumbliness of the meat.
In conclusion, the dietary supplementation of 15% CKMS had no negative effect on broiler growth and positively influenced bird welfare in terms of mortality and foot pad health. Therefore, the addition of 15% CKMS to maize-based diets is considered an advantageous feeding strategy in broiler production.
A 4 × 2 factorial experiment was conducted to investigate the effect of inclusion of spray-dried porcine plasma (SDPP), in lieu of meat meal, in the starter diet on performance and digestive physiology of broiler chickens between hatch and 35 d of age. Four levels of SDPP (0, 5, 10 or 20 g/kg) were included in the starter diets in lieu of meat meal on either wheat- or maize-based diets.
Over the first 10 d, and throughout the 35-d experimental period, birds gained more body weight with increasing concentrations of SDPP regardless to the type of grain used. Inclusion of SDPP in the starter diet markedly improved feed per gain in the starter phase and across the 35-d study. There was no significant effect of the type of grain and its interaction with SDPP on the body weight gain and feed per gain for the two assessed periods.
At d 10, the relative weight of the gizzard+proventriculus, spleen and liver increased with increasing concentrations of SDPP.
At 24 d of age, the grain and SDPP inclusion significantly interacted, depressing the weight of bursa and spleen in birds that received the highest concentration of SDPP in the maize-based diet. Birds fed on the maize-based diets had higher relative weight of pancreas than those on the wheat-based diets.
Increasing concentrations of SDPP in the starter diet improved the activities of maltase, sucrase and alkaline phosphatase at 24 d of age. The interaction of grain and SDPP concentration was significant for sucrase activity in birds on the wheat-based diets. Chickens on maize-based diets had higher alkaline phosphatase and maltase activities than those on wheat-based diets.
Chicks that were offered SDPP-containing starter diets had longer villi, deeper crypts and lower villi/crypt than the control at 24 d of age regardless of the grain type used. Furthermore, longer villi and larger villi/crypt were found in chicken groups fed on wheat-based diets than those on maize-based diets.
Chickens on maize-based diets had higher dressing percentage and relative breast weight than those on wheat-based diets at 35 d of age.
It can be concluded that supplementation of starter diets with SDPP would be beneficial to the long-term growth of broiler chickens. The effect of the basal grain used in the diet is minimal.
The effects of different dietary energy concentrations on ostrich production variables were examined in two separate trials. The first trial tracked changes in production variables from the pre-starter phase through the starter phase and grower phase. The second trial was based on the finisher phase per se. In both trials, the influence of dietary energy on feed intake, feed conversion ratio (FCR) and growth variables was investigated. Additionally, basic abattoir weights were recorded, and measurements of the feathers and skin were performed.
In both trials, three diets with different concentrations of dietary energy were given during each phase where the low-, medium- and high-energy concentrations for each phase were as follows: 13.5, 14.5 and 15.5 MJ ME/kg feed pre-starter; 12.5, 13.5 and 14.5 MJ ME/kg feed starter; 10.5, 11.5 and 12.5 MJ ME/kg feed grower and 9.5, 10.5 and 11.5 MJ ME/kg feed finisher. Feed and water were available ad libitum in both trials.
Overall, it was found that the best performance for growth, FCR, skin size and grade, live weight, carcass weight and thigh weight were obtained on the medium-energy diet during the pre-starter, starter and grower phases.
During the finisher phase, improved growth rate and tanned skin size was found in birds given the diet with the highest energy concentration (11.5 MJ ME/kg feed). Carcass weight, growth rate and certain feather variables were also significantly influenced by gender.
This study was conducted at high altitude (2100 m above sea level). A total of 208 d-old male broilers (Ross 308) were randomised across 16 floor pens and reared up to 42 d. A normal-protein diet (NPD) was formulated according to the National Research Council. A reduced-protein diet (RPD) was prepared with dietary protein reduced by 30 g/kg relative to that of the NPD. Two additional diets were prepared by adding 2 and 4 g L-arginine (ARG)/kg to the RPD. At the end of trial (42 d), blood sampling was done and carcass characteristics were recorded.
ARG supplementation of the RPD at 4 g improved feed:gain in the growing stage and throughout the trial compared with the RPD.
The right-to-total ventricular weight ratio was significantly increased in birds fed on RPD compared with those fed on NPD or ARG-supplemented RPD.
Feeding RPD caused a significant decrease in plasma concentrations of nitric oxide (NO) and uric acid. Plasma NO level, however, was restored by ARG supplementation of RPD. ARG supplementation of RPD, however, significantly reduced the rate of pulmonary hypertension syndrome mortality compared to the negative control fed on RPD.
Concomitant presence of mycotoxins is more likely to appear than a single mycotoxicosis since many mycotoxigenic fungi grow and produce their toxic metabolites under similar conditions.
The present study was designed to evaluate the efficacy of 4 mycotoxin binders to protect meat-type chickens against single and concomitant administration in the feed of two mycotoxins, namely aflatoxin B1 (AFB1) and ochratoxin A (OTA) both at concentration of 0.1 mg/kg.
A total of 440 as hatched, d-old, Ross 308 broilers were reared for 42 d. There were 11 dietary treatments. Chickens were fed on either an uncontaminated basal diet, basal diet and AFB1, basal with concomitant presence of AFB1 and OTA, basal diet and three binders A, B and C (1%) with or without AFB1 or basal diet and binder D (0.5%) with or without concomitant presence of AFB1 and OTA. Performance, carcass yield and several biochemical parameters were examined.
Mycotoxin concentration in liver and breast muscle samples was determined. Broiler performance under concomitant mycotoxin contamination was poorer than that under single mycotoxicosis. Mycotoxin presence increased relative heart weight compared to that of broilers fed on uncontaminated diets. Only OTA and not AFB1 was detected and only in the liver. OTA concentration was four-fold lower in broilers fed on a diet with binder compared to those fed on contaminated diets without binder.
In conclusion, the study revealed that binder composition and presence or not of multiple toxins may be important factors for optimum broiler performance under mycotoxicosis.
The purpose of this study was to evaluate the effects of supplementing diets with three types of fermented Ginkgo-leaves (FGL) on growth, antioxidant capacity, intestinal morphology and microbial ecology in broiler chicks.
A total of 300 d-old broilers were randomly allocated to 4 dietary treatments with 6 replications of 10 birds each. Birds were fed on basal diets (Control) or basal diets supplemented with 0.5% FGL with Candida utilis (CF group), Aspergillus niger (AF group) or their combined fermentation (CAF group), respectively, for a 42 d feeding trial.
AF and CAF supplementation improved body weight gain (BWG) (22–42 d) and feed conversion ratio (22–42 d and 1–42 d). Concentrations of serum α-tocopherol in CAF group, as well as hepatic α-tocopherol in the three FGL groups were increased, while hepatic reactive oxygen species (ROS) levels were greatly decreased in group AF and CAF. Chickens in AF and CAF groups had decreased hepatic protein carbonyls and malondialdehyde (MDA), as well as jejunal and ileal protein carbonyls. The total superoxide dismutase (T-SOD) activities and glutathione (GSH) of both jejunum and ileum of the CAF group were higher than the other groups.
Duodenal and jejunal villous height of birds fed on the AF and CAF diets were increased, while jejunal crypt depth (CD) was decreased. Furthermore, birds fed on AF and CAF supplemented diets had increased ileal lactobacilli populations. Decreased ileal and caecal Escherichia coli and Salmonellas populations was found for the birds fed on CAF supplemented diets.
The present study may indicate that the improved feed efficiency and intestinal functions in the group supplemented with AF and CAF are directly connected with the improved antioxidant capacity and intestinal microbial ecology.
This study was designed to evaluate the effects of two different complex probiotic supplementations on the growth performance, meat quality, excreta microflora, nutrient retention, blood metabolic profile and noxious gas emissions in broilers.
A total of 612 conventional healthy 1-d-old Ross 308 broilers with body weight of 41 ± 0.3 g were randomly divided into 3 treatments with 12 replicate cages, with 17 broilers in each cage and fed with the following diets: CON-Basal diet, T1-CON + Probiotic A, T2-CON + Probiotic B.
Significant results were observed on body weight gain, but not on feed conversation ratio and feed intake, in the whole experimental period. Increased faecal lactobacillus counts were found with probiotics supplementation. However, no significant effects were found for meat quality, nutrient retention, blood metabolic profile or noxious gas emissions.
In conclusion, both multi-strain probiotics had beneficial effects on growth performance, drip loss percentage and faecal Lactobacillus counts in broilers.
The aim of this study was to investigate the effect of dietary supplementation of green tea (Camellia sinensis) catechins in quail (Coturnix coturnix japonica).
Quail were fed with a basal diet, and the treatment groups were fed on the basal diet with 1.25 or 2.50 g/kg catechin supplementation for 30 d.
Fattening performance and meat quality of the quail were estimated. Serum total antioxidant status (TAS), plasma and liver malondialdehyde (MDA) and some serum biochemical parameters were measured.
The results showed that catechin supplementation did not affect live weight, feed intake, feed conversion ratio, carcass weight, carcass dressing or the nutrient composition of breast and thigh meats. The water holding capacity (WHC) of breast meat was increased in the 2.50 g/kg catechin treatment. Catechin supplementation increased the serum TAS, but decreased plasma MDA and liver MDA concentration as well as serum glucose and total cholesterol levels. Serum triglyceride and total protein levels were not affected by catechin supplementation.
In conclusion, catechins have effective antioxidant hypoglycaemic and hypocholesterolaemic properties, as well as having the potential to increase meat quality in fattening quail. On the other hand, catechin supplementation did not have any negative effect on the fattening performance, meat nutrient composition and fattening costs in fattening quail.
An experiment with a 2 × 3 factorial design with two concentrations of dietary betaine (0 and 600 mg/kg) and three dietary concentrations of methionine (0, 600 and 1200 mg/kg) was conducted using goslings to estimate growth, nutrient utilisation and digestibility of amino acids from 21 to 70 d of age.
Three hundred geese were randomised at 18 d of age into 6 groups with 5 replicates per treatment and 10 geese per replicate.
Increasing dietary concentrations of methionine gave a linear increase in body weight and average daily gain. The coefficient of crude fat retention increased as dietary methionine increased and there was a significant non-linear response to increasing dietary methionine. Similarly, increasing supplemental methionine gave linear increases in the digestibility of methionine and cysteine.
The results of this study indicated that optimal dietary supplementation of methionine could increase growth performance and methionine and cysteine utilisation in growing goslings. Betaine supplementation had no apparent sparing effect on methionine needs for growth performance, but did improve the apparent cysteine digestibility.
The objective of this study was to investigate and compare the effects of α-tocopherol acetate (vitamin E (VE)) and microencapsulated VE (MVE) on growth performance, meat quality and antioxidant capacity in broiler chickens.
A total of 360 d-old broiler chicks were procured and randomly allocated into three groups with 6 replicates. Each replicate had 20 chickens. Chickens were fed with basal diets (CON group) or experimental diets supplemented with 20 mg/kg VE (VE group) or 20 mg/kg MVE (MVE group) for 42 d.
The results showed that the MVE group had higher body weight gain (BWG) than the CON and VE groups, and higher gain/feed ratio (G/F ratio) than the CON group during the period of 22–42 d. During the whole experiment, a higher increase in BWG was found in the MVE group than the CON group.
Chickens fed on diets supplemented with the VE or MVE had lower abdominal fat percentage, higher pH and antioxidant enzyme activity than the CON group in the breast meat.
There was an increased tendency in the hepatic glutathione peroxidase (GSH-Px) enzyme activity of the VE and MVE groups than the CON group. The hepatic mitochondrial total antioxidant capacity and GSH-Px enzyme activity in the MVE group were higher than the CON group. Hepatic 2,2-dipheny-?-picrylhydrazyl scavenging activity of the MVE group was higher than the CON group.
These results suggested that the dietary addition of VE or MVE could improve breast meat quality in broilers. MVE supplementation may improve growth performance, hepatic mitochondrial antioxidant capacity and free radical scavenging capacity in chickens. In addition, dietary supplementation of MVE gave better broiler growth performance than VE.