Archives of Animal Nutrition最新文献

This study aimed to determine whether butyric acid glycerides can replace conventional growth promoters, favour intestinal health, and improve performance. A total of 420 birds were used, divided into four groups with seven repetitions per group (n = 15), as follows: NC, negative control (no promoter); PC, positive control (basal diet + enramycin + salinomycin); MDT-BUT, a diet supplemented with mono-, di-, and triglycerides of butyric acid; TRI-BUT, a diet supplemented with tributyrin of butyric acid glycerides. Productive performance was measured on days 1, 21, 35, and 42. Excreta were collected for counting Escherichia coli and coliforms on days 21 and 42. Blood samples were collected at 42 days of age to analyse oxidant/antioxidant status, and the intestine was removed for intestinal morphometry. From 1 to 42 days, there was greater body weight, weight gain, and feed conversion in the PC, MDT-BUT, and TRI-BUT groups than in the NC group; the production efficiency index was 21.10% higher in all groups than in the NC group (p = 0.001). At 21 days, there were lower E. coli counts of 86.8% in the TRI-BUT and 99.7% in PC groups than in the NC and MDT-BUT groups (p < 0.001), while at 42 days, lower counts were found in the PC, MDT-BUT, and TRI-BUT groups than the NC group (p < 0.001). There were lower total protein and globulin levels in the MDT-BUT and TRI-BUT groups than in the NC group (p = 0.001). Cholesterol levels were lower in the TRI-BUT group, followed by MDT-BUT and PC groups, than in the NC group (p = 0.001), while lower triglyceride levels were found in the TRI-BUT group than in the NC and PC groups (p = 0.001). There were lower levels of lipid peroxidation and reactive oxygen species in the TRI-BUT group, followed by the PC group than the NC group (p < 0.001); on the other hand, there were higher protein thiol levels in the TRI-BUT group than the NC group (p = 0.041). The villus:crypt ratio increase was 79.4% in the TRI-BUT group, followed by the 45.1% PC and 19.8% MDT-BUT groups than the NC (p < 0.001). These findings suggest that adding butyric acid confers antimicrobial and antioxidant activity and improves birds' production efficiency, intestinal health, and metabolism. Butyric acid glycerides are an effective alternative to conventional growth promoters.

To evaluate the effects of temperature and lactic acid bacteria (LAB) inoculants on oat silage in Loess Plateau of China, oat was harvested at dough stage, inoculated without (Control) or with LAB inoculants Synlac I (SLI, Lactobacillus plantarum and Pedioccocus acidilactici) and a selected strain HT1 (L. rhamnosus) and ensiled at 25°C (T25), 35°C (T35) and 45°C (T45). The fermentation quality was measured after 60 d of ensiling and the aerobic exposure was conducted at 30°C for 9 d. The results showed that control silage (stored at 25°C) had better fermentation quality than that ensiled at 35°C or 45°C. High temperature of 45°C resulted in sharp decreases in LAB counts and lactic acid concentration and increases in pH and NH₃-N concentration in the control group. Inoculation improved the fermentation quality, and HT1 was more effective than SLI at 35°C and 45°C, while SLI showed better performance at 25°C. All silages displayed mild fluctuation for all treatments at the first 3 d of aerobic exposure, and significant differences were observed among treatments after that. Both control and inoculated silages stored at 25°C showed a sharp pH increase, while HT1 treated silages stored at 35°C and 45°C maintained stable pH and better fermentation quality during the aerobic exposure. In conclusion, SLI was suitable for oat silage fermentation at normal atmospheric temperature (25°C), while HT1 was more effective in improving DM recovery, fermentation quality and aerobic stability of oat silage at high temperature during summer in the Loess Plateau of China.

The purpose of this study is to investigate the nutritional changes of degraded rapeseed meal and its effects on growth performance, nutrient digestibility and health status of broilers. Raw rapeseed meal (CON), degraded by enzymolysis (protease, ERM), fermentation (Bacillus subtilis, FRM) or both (DRM) were included in diets at 25% and fed to 480 yellow-feathered broilers at 22-63 d of age. Results showed that rapeseed peptide contents (≤1 kDa) were increased (p < 0.05) from 4.13% (CON) to 35.5% (ERM), 24.1% (FRM) and 50.4% (DRM); glucosinolate and erucic acid in DRM were decreased (p < 0.05) by 71.6% and 86.2%, respectively, compared to CON. There were increases (p ≤ 0.029) in feed intake, body weight gain, feed efficiency and precaecal digestibility of dry matter, crude protein, methionine, isoleucine, leucine, lysine, cysteine, phenylalanine, tyrosine, threonine, tryptophan and valine in the three degraded diets. Also, serum immunoglobulin (Ig) A, IgG, glutathione peroxidase, superoxide dismutase and catalase were raised (p ≤ 0.034) in the degraded diets. Additionally, DRM showed more pronounced effects (p < 0.05) on variables related to growth, digestibility and health than ERM and FRM. It is concluded that rapeseed meal degraded by both enzymolysis and fermentation can increase its nutritional values and application in broilers.

This study investigated the effect of feeding different levels of protected fat (calcium soaps of tallow) on fattening performance, carcass characteristics, meat quality, fatty acid composition of Longissimus Thoracis (LT) muscle and economic evaluation of 45 fat-tailed Morkaraman male lambs. The lambs were randomly divided into three groups including a control diet without protected fat (CON), supplemented with 2% protected fat (group PF2), and supplemented with 4% protected fat (group PF4) during the fattening period. Eight lambs randomly selected from each group were slaughtered to determine carcass characteristics and meat quality. Supplementing protected fat significantly improved the fattening performance and carcass characteristics (p<0.05). The groups were similar in terms of pH, colour, ether extract, dry matter and sensory evaluations, except for the crude protein of group PF2. Myristic acid and stearic acid (p<0.05), which are saturated fatty acids (SFA), were decreased with the supplementation of protected fat, while palmitic acid was increased (p<0.01). The fattening with protected fat had a highly significant positive effect on important unsaturated fatty acids such as oleic acid (p<0.01) and resulted in an increase of approximately 91% in the conjugated linoleic acid (CLA) (p<0.05). SFA was significantly decreased, and health indicators were improved (p<0.01). In conclusion, the supplementation of protected fat had a positive effect on fattening performance, carcass traits, chemical, sensory properties and economic evaluation.

Adequate levels of dietary fibre can reduce the risk of intestinal health disorders in rabbits after weaning. Therefore, it was the aim of the study to investigate the impact of different lignocellulose and cellulose addition to rabbits' diets on performance and intestinal traits in lactating does and weaned rabbits. A total of 60 rabbit does (4.41 ± 0.45 kg body weight) were fed isonitrogenous diets with lignocellulose and cellulose inclusion rates [%] of 0/8, 2/6, 4/4, 6/2 and 8/0, resulting in dietary lignin-to-cellulose ratios of 0.26, 0.30, 0.32, 0.34 and 0.40, respectively. The diets were fed from 4 d ante partum (a.p.) until day 28 post partum (p.p. weaning). After weaning, 40 young rabbits from each feeding group were fed the same diets for 12 d, when 10 rabbits per group were sacrificed. Body weight gain (BWG), feed intake and feed conversion ratio were obtained. Gastrointestinal content and gut tissue were obtained from the growing rabbits and pH, short-chain fatty acids (SCFA) concentration and gut morphology were investigated. Digestive disorders were scored, and the sanitary risk index was calculated. Does fed the highest lignocellulose addition increased their feed intake [g · kg BW^-1 · d^-1] in the first two weeks p.p. (p < 0.001) and increased BWG (p < 0.001) but without impact on their offsprings' performance. Weaned rabbits fed the highest lignocellulose inclusion showed a reduced feed intake and increased sanitary risk index. Additionally, a higher number of rabbits showed intestinal disorders for a short time (1-2 d, p < 0.001). In the colon content, a higher pH and a lower dry matter content were observed in this group. Caecal contents of 40-d old rabbits showed lower total SCFA, acetate and propionate and higher i-valerate and L-lactate concentrations after feeding diets with high lignocellulose contents. The diet did not influence the acetate-to-propionate ratio. No histomorphological changes were observed in the jejunum, while crypt depth and width were reduced in the caecum of weaned rabbits fed diets with lignocellulose addition. It can be concluded that different proportions of lignocellulose to cellulose addition to rabbits' diets have an impact on health and performance with differences between does and weaned rabbits. While a high lignocellulose inclusion proved beneficial for does, for weaned rabbits, a lower addition should be preferred.

The present study was conducted to evaluate whether the deacetylation degree of chitosan (low: 70% vs. high: 90%) and its dietary level (0, 200, 400, 800, 1600 mg/kg diet) would affect laying performance, faeces viscosity, egg quality, egg and serum biochemistry of layers. For the experimental feeding period of 8 weeks, 140 four weeks old Hisex Brown layers were divided into 10 treatment groups, comprising 14 birds each. The birds were housed in individual cages in a complete randomised design. Performance was assessed by recording feed intake, egg weight, daily egg production, egg quality and egg biochemistry. Serum biochemistry parameters were determined at the beginning and end of the experiment and faeces viscosity at the end of the experiment. Feed conversion ratio and faeces viscosity were deteriorated by increased level of chitosan. Lightness of egg yolk was significantly increased in animals receiving high-degree deacetylated chitosan compared to low-degree deacetylated chitosan. Yellowness of egg yolk was affected by interaction of deacetylation degree and level of chitosan. Yolk cholesterol concentration was lower in groups receiving high deacetylated chitosan by increasing chitosan level, while laying hens fed low deacetylated chitosan had a higher level of yolk cholesterol. A significant interaction between degree of deacetylation and chitosan level was determined for serum glucose and calcium concentration. Serum total antioxidant content increased with higher levels of dietary chitosan. In conclusion, dietary level or different degrees of deacetylated chitosan may reduce yolk cholesterol and improve serum antioxidant status. However, feed conversion ratio and faeces viscosity were impaired by increasing levels of chitosan supplementation, and lightness of yolk was increased by supplementation of chitosan with a high degree of deacetylation.

Pyrrolizidine alkaloid (PA) producing plants like Senecio jacobaea or Senecio vernalis are undesirable in fields for forage production, since PA are toxic to animals and humans. Previous studies have shown that ensiling can decrease the PA content in forages; however, no direct comparison of diverse PA from different Senecio spp. under various ensiling conditions has been made. Therefore, it was hypothesised that individual PA might react differently to ensiling, and silage inoculation with Lactobacillus will affect PA degradation because of a quick drop in pH, contrastingly to poor silage qualities resulting from contamination with soil. Laboratory scale grass silages were prepared in a multifactorial design with two levels of dry matter contents, four ensiling treatments and two storage durations (10 and 90 d). For each combination, four replicates were prepared individually. Ensiling treatments were (1) 10 ml water per kg fresh matter as control (CON), (2) 10 ml heterofermentative Lactobacillus buchneri strain LN4637 at 3 · 10⁵ cfu/kg fresh matter plus 25 g molasses/kg fresh matter (LBHE), (3) 10 ml homofermentative lactobacilli at 3 · 10⁵ cfu/kg fresh matter plus 25 g molasses/kg fresh matter (LBHO) and (4) 10 g soil/kg fresh matter (SOIL). Treatments affected formation of fermentation acids. Acetic acid was highest with treatment LBHE, and butyric acid was highest with treatment SOIL. All ensiling treatments effectively reduced total PA content by degrading the PA N-oxide (PANO) fraction. In parallel, though, the fraction of the tertiary base forms increased by around one-tenth of the original PANO content. Contents of jaconine and senkirkine were higher after ensiling than before, with regards to the sum of PA and PANO for jaconine, indicating higher stability or new formation through degradation of other PA. Overall, ensiling offers opportunities to decrease the PA-PANO content in feed and therefore lowers the risk of intoxication by Senecio in livestock.

Knowledge of energy requirements is necessary to optimise the nutritional management of animals. For tortoises, very little is known about their nutrient and energy requirements. Data on substrate oxidation and the implications of starch or fat intake on the energy metabolism are lacking. The present study compared the daily energy expenditures (DEE) of red-footed tortoises (Chelonoidis carbonaria) that were fed three extruded diets: a control diet high in fibre and two test diets, one with high starch content and another with high fat content. A total of 18 tortoises (5.5 ± 1.18 kg) were used in a completely randomised design, with 6 animals per diet. After 14 months of experimental diet intake and 48 h of preliminary fasting, the animals were kept for 12 h in 70-l respiratory chambers. An open "push mode" system was used to determine the carbon dioxide production and oxygen consumption levels for the subsequent calculations of DEE. The data were analysed with ANOVA, and the means were compared by using Tukey's test (p < 0.05). The body weights, chamber temperatures and food intakes of the tortoises were similar among the treatments (p > 0.05). There were no significant differences in oxygen consumption (21.7 ± 3.16 ml · kg^-1 · h^-1), carbon dioxide production (18.1 ± 1.96 ml · kg^-1 · h^-1), or DEE (9.7 ± 1.04 kJ · kg^-1 d^-1) between diets or sex (p > 0.05). The respiratory quotients (0.84 ± 0.11) were also similar among the diets (p > 0.05). The DEE of red footed tortoises did not differ after a long-term starch or fat intake.

The aim of the present study was to investigate the effects of substituting dietary barley grain by different sources and levels of fat on performance and meat quality of Holstein young bulls. Twenty-eight Holstein male calves, 274 ± 32 kg initial body weight, were used in a completely randomised design with a 2 × 2 factorial treatment arrangement for 100 d (with 10 d of adaptation). Seven animals were randomly allocated per treatment. Four dietary treatments were tested, which included: (1) diet supplemented with saturated fat (Energizer® RP10) at low level (diet with high barley and starch content), (2) diet supplemented with saturated fat at high level (diet with low barley and starch content), (3) diet supplemented with unsaturated fat (Persiafat) at low level (diet with high barley and starch content) and (4) diet supplemented with unsaturated fat at high level (diet with low barley and starch content). The dry matter intake, average daily gain, feed conversion ratio and carcass traits were not affected by supplemental fat sources and levels. Total tract digestibility of acid detergent fibre was improved after inclusion of both rumen-protected fat sources while other nutrient digestibilities were not affected by the fat sources or levels. In conclusion, partial replacing of dietary starch with fat supplements has not negative effects on calves' performance and digestibility of neutral detergent fibre.