The effect of fly maggot in pig feeding diets on growth performance and gut microbial balance in Ningxiang pigs

Fly maggot meal has been regarded as one of the substitutes of fish meal and soybean meal in pig feed. However, its effects on pig growth performance and faecal micro-organism remain unclear. The purpose of this study was to investigate the effect of dietary fly maggot meal on fattening performance, plasma indices related to gut hormones, immunity and faecal microbial communities composition of finishing pigs. A total of 40 Ningxiang fattening pigs were randomly allocated to two dietary treatments and pigs in each group were arranged by control group (CK) diet or 8% maggot meal group (MMG) diet for 45 days respectively. Growth performance, indices of gut hormones and immunity in plasma were evaluated. Microbiota composition in faeces was determined using 16S rDNA Amplicon Sequencing. The results showed that dietary MMG did not affect gut hormones and immune proteins in the trial compared with CK group (p > .05). However, dietary MMG significantly increased average daily gain (ADG). The population of the Firmicutes in MMG treatment was increased, while the percentage of the Bacteroidetes was decreased (p < .05). In particular, the number of Clostridiales related to hydrolyzed sugar and protein were increased (p < .05). It can inhibit the growth of harmful intestinal bacteria, promote the proliferation of beneficial bacteria and effectively improve the ability of digestion and absorption of nutrients. In conclusion, a diet containing 8% MMG changed the proportion of intestinal micro-organisms in finishing pigs, especially the higher richness of Firmicutes, and promoted the fattening ability of pigs to a certain extent. These changes should benefit finishing pig production during fattening period.     

Growth performance,carcass characteristics,meat quality and serum profile of broiler chicks fed on housefly maggot meal as a replacement of soybean meal

A study was conducted to invesstigate the housefly maggot meal (HMM) as an alternative protein source to replace the soybean meal in broiler chick's diet. A total of 720 1-day-old male broiler chicks were divided into three groups and fed diets formulated with HMM to replace soybean meal at the rate of 0%, 4% and 8%. The study lasted for 42 days in two phases. Results showed that HMM addition did not markedly affect body weight, average daily body weight gain and average daily feed intake of the broiler chicks. Feed conversion ratio increased linearly (1–21 days) in starter or quadratically (22–42 days) in the grower phase. HMM non-significantly increased the feed intake and body weight during the grower phase. Slight changes were observed for decrease of blood biochemical indices in the platelets (day 21), and alkaline phosphatase and lysozyme (day 42), and increase for red blood cells, packed cell volume, total protein and uric acid on day 42; however, the fluctuations were within the physiological range. Non-significant effects were observed for carcass composition and meat quality, except that HMM numerically reduced the shear force of breast muscle (linear, p = .058). These results are the strong evidence that HMM can be used as an alternative protein source at 8% in broiler chick's diet without any adverse effect on chick's performance.     

Yellow mealworm,Tenebrio molitor (Col: Tenebrionidae), larvae powder as dietary protein sources for broiler chickens: Effects on growth performance,carcass traits,selected intestinal microbiota and blood parameters

This study was conducted to evaluate the effects of dietary Tenebrio molitor larvae meal (TM meal) inclusion on the performance, carcass traits, caecum microbiota and blood parameters of broiler chickens. A total of 180-day-old chickens were allocated to three dietary groups with five replicate pens (12 birds/pen). Experimental diets were included a corn-soybean basal diet, and two diets with 2.5% and 5% TM. TM-included diets have been administered for periods of starter (1–10 days) and grower (11–25 days). A regular finisher diet was given to all groups during the 26–42 days of age. Diets containing TM meal did not influence feed intake and mortality percentage. Feed conversion ratio was lower with the 2.5% TM meal diet compared with the control group at starter period (p < .05). Besides, broiler chickens fed TM meal included diet had a higher body weight gain than the control group during 1–10 days of age (p < .05). The carcass characteristics and length and weight of different parts of small and large intestines were not influenced by diets. TM meal inclusion decreased the albumin-to-globulin ratio compared with the control group (p < .05). Additionally, lower total count of aerobic and Escherichia coli bacteria was observed in response to diet inclusion of 5% TM meal. Overall, the inclusion of TM meal in broilers' diet improved body weight gain and feed conversion ratio in the starting period, decreased albumin-to-globulin ratio and E. coli bacteria content.     

Evaluating the suitability of maggot meal as a partial substitute of soya bean on the productive traits,digestibility indices and organoleptic properties of broiler meat

This study was conducted to replace soya bean meal with maggot meal at difference percentages. A total of 120 one‐day‐old broiler chicks were divided into four groups. Four diets were formulated with maggot meal to replace soya bean meal at the rate of 0%, 10%, 20% and 30% designated as A, B, C and D respectively. Feed and water were offered ad libitum during the study which lasted for 28 days. Feed intake decreased significantly in treated groups while body weight, Feed conversion ratio and dressing percentage increased significantly in group D. Apparent metabolizable energy increased significantly in the group fed 30% maggot meal; however, no significant difference was found in dry matter, crude protein, crude fibre, ether extract, ash and nitrogen free extract between the control and treated groups. The result of sensory evaluation revealed that tenderness and juiciness increased significantly in group C and B respectively. The colour and flavour were most accepted in group B and C. The results indicate that replacement of soya bean meal at the rate of 30% in broiler feed produced most favourable results.     

Effect of dietary Moringa stem meal level on growth performance,slaughter performance and serum biochemical parameters in geese

Moringa stem meal (MSM) with a high level of crude fibre (CF) might be developed and utilized in herbivorous geese as an unconventional feedstuff. The aim of this study was to investigate the effect of the MSM level in the diet on the growth performance, slaughter performance, breast meat quality and serum biochemical parameters in geese from 22 to 70 days of age. A one-factor completely randomized design was adopted in our study. A total of one thousand eight 21-day-old geese were randomly divided into six groups, with six replicates per group and 28 birds per replicate. The geese were fed diets containing MSM levels of 0, 20, 40, 60, 80 or 100 g/kg during day 22–70. The dietary MSM level had no effect (p > .05) on the final body weight (BW), average daily gain (ADG) or average daily feed intake (ADFI). The feed/gain ratio (F/G) increased linearly (p < .001) as the dietary MSM level increased. No differences (p > .05) were observed in the slaughter performance, meat quality and the relative organ weight (except for thymus) of the geese (p > .05). The relative weight of the thymus in the geese fed diets with supplementation of MSM was higher than that in the non-supplemented MSM control group (p < .05). In addition, 100 g MSM/kg of diet decreased the serum glucose (GLU) level (p < .05) and increased the alanine transaminase (ALT) enzyme activity (p = .03). Dietary MSM levels of no more than 60 g/kg had no effects on the growth performance and slaughter performance, whereas diets with 100 g MSM/kg increased the F/G and serum ALT enzyme activity, as well as decreasing the serum GLU level. Therefore, MSM provided at a reasonable level could be developed as an unconventional feedstuff for geese at the finisher period.     

Effect of Moringa oleifera supplementation on productive performance,colostrum composition and serum biochemical indexes of sow

Moringa oleifera has been considered as a potential functional feed or food, since it contains multiple components beneficial to animal and human. However, little is known about the effects of Moringa oleifera supplementation on productive performances in sows. In the current study, the results showed that dietary Moringa oleifera significantly decreased the farrowing length and the number of stillborn (p < .05), while had an increasing trend in the number of live-born (0.05 < p < .10). Furthermore, 8% Moringa oleifera supplementation significantly elevated protein levels in the colostrum (p < .05); 4% Moringa oleifera lowed serum urea nitrogen of sows after 90 days of gestation (p < .05) and significantly decreased serum glucose on 10 days of lactation (p < .05). Both groups showed significant elevation in serum T-AOC activity (p < .05). The serum malondialdehyde (MDA) of sows declined significantly in 4% Moringa oleifera addition group (p < .05). 8% Moringa oleifera meal significantly elevated serum CAT activity after 60 days of gestation (p < .05), while decreased the serum MDA level and increased the serum GSH-Px activity of sows at 10 days of lactation (p < .05). Of piglets, both two dosages of Moringa oleifera supplementation essentially reduced the serum urea nitrogen (p < .05), and 4% Moringa oleifera meal increased serum total protein (p < .05). In addition, piglets that received 8% Moringa oleifera had the highest serum CAT and SOD activities among all groups (p < .05). The present study indicated that Moringa oleifera supplementation could enhance the reproduction performances, elevate protein levels in the colostrum and improve the serum antioxidant indices in both sows and piglets.     

Effects of milk thistle meal on performance,ileal bacterial enumeration,jejunal morphology and blood lipid peroxidation in laying hens fed diets with different levels of metabolizable energy

This study was conducted to evaluate the effects of different levels of milk thistle meal on performance, blood biochemical indices, ileal bacterial counts and intestinal histology in laying hens fed diets containing different levels of metabolizable energy. A total number of 200 Leghorn laying hens (Hy‐Line W‐36) were randomly assigned to eight experimental treatments with five cage replicates of five birds each. Dietary treatments consisted of four levels of milk thistle meal (0%, 15%, 30% and 60%) and two levels of AME_n (11.09 and 12.34 MJ/kg) fed over a period of 80 days. In vitro studies revealed that the total phenolic component of milk thistle meal was 470.64 mg gallic acid equivalent/g of the sample, and its antioxidant activity for inhibiting the 2‐2‐diphenyl‐1‐picrichydrazyl free radical and reducing ferric ions was about 21% higher than that of butylated hydroxyltoluene (p < .05). Diets containing high level of AME_n led to improved egg production (p < .05), egg weight (p < .05), egg mass (p < .01) and feed conversion ratio (p < .01). In addition, offering diets containing high energy significantly enhanced (p < .01) serum triglyceride and malondialdehyde (MDA) concentrations as well as jejunal villus height. Dietary supplementation of 3% milk thistle meal resulted in the best feed conversion ratio (p < .05), reduction of ileal Escherichia coli enumeration (p < .01) and an enhancement in the villus height‐to‐crypt depth ratio (p < .05). Furthermore, feeding incremental levels of this meal led to remarkable decrease in serum cholesterol, triglyceride and MDA (p < .01) concentrations while significant increase in blood high‐density lipoprotein content and goblet cell numbers (p < .05). The present findings indicate that milk thistle meal with high antioxidant and antibacterial properties in laying hen diets may improve health indices and productive performance.     

Response of meat chickens to different sources of arginine in low-protein diets

Arginine activity in broiler diets can be supplied by L-arginine (Arg), guanidinoacetic acid (GAA) and L-citrulline (Cit), all of which are commercially available. This study was conducted to assess the effects of Arg source and level on broiler performance, nutrient digestibility and carcass parameters. Day-old Ross 308 cockerels (n = 768) were assigned to one of eight dietary treatments using a completely randomized design: normal protein (NP), low protein deficient in Arg (LP) and LP with two levels of either Arg (0.238% and 0.476%), GAA (0.309% and 0.618%) or Cit (0.238 and 0.476%). The LP was 5 percentage points lower in protein level than the NP. Wheat, sorghum, soya bean meal, canola meal, and meat and bone meal-based diets were fed over three feeding phases to 6 replicate floor pens with 16 birds each. Compared to NP, birds fed LP had reduced feed intake (FI, p < 0.001), reduced body weight gain (BWG, p < 0.001) and increased feed conversion ratio (FCR, p < 0.001) from day 0 to day 35. Additions of Arg or Cit to the LP at both levels resulted in increased BWG and reduced FCR (p < 0.05). Birds fed LP with GAA added had lower FCR (p < 0.05) but not higher BWG (p > 0.05) compared with the LP observed from day 0 to day 35. Supplementation of Arg, Cit and the low level of GAA to LP resulted in increased carcass yield, bone length, diameter and ash (p < 0.05) but did not increase ileal energy or nitrogen digestibility (p > 0.05). The findings indicate that Cit is an efficacious source of Arg activity in Arg-deficient diets.     

Effect of fermented blood cells on growth performance and intestinal characteristics of weaned piglets

The increase in feed costs has led feeder to replace protein source. Blood meal can be used in piglet diets instead of fish meal (FM). The objective of this study was to investigate the effect of fermented blood cells (FBCs) on the growth performance and intestinal health of weaned piglets. One hundred eighty 28‐day‐old piglets were assigned and were divided into 4 groups (9 L per groups and 5 pigs per litters) randomly. The piglets were fed one of four experimental diets, fish meal, blood cells (BCs), liquid‐state fermented blood cells (LFBCs) or solid‐state fermented blood cells (SFBCs) respectively. The dietary with LFBCs and SFBCs increased the average daily gain and feed intake (ADFI) and average daily gain (ADG) (p < .05). In duodenum, LFBC group increased the villous height (p < .05). The SFBC and LFBC group significantly increased the villous height (p < .05) in the jejunum. Fermented blood cells exhibit a positive regulatory function on the intestinal tract and modulate intestinal microflora. Compared with the fish meal group, the CAT, GSH‐PX and SOD activity, and MDA level was no significant differences in jejunum and plasma of weaned piglets (p > .05). LFBCs and SFBCs significantly increased the bifidobacteria and lactobacillus number in the caecum (p < .05). Dietary LFBCs increased the expression of ZO‐1 mRNA in the jejunal of weaned piglets (p < .05). In conclusion, dietary with fermented blood cells in weaned piglets had improved growth performance and intestinal health of weaned piglets.     

Effects of beak trimming on the performance,beak length,behavior, and carcass traits of a local broiler breed reared in battery cages

This study investigated the effects of beak trimming on a local broiler breed. A total of 648 one‐day‐old birds were randomly allocated into three treatments: no trimming (NBT), infrared beak trimming (IRBT), and hot‐blade beak trimming (HBBT). The performance, beak length, behavior, carcass traits, organ percentages, and meat quality were inspected. The body weight (BW) from 7 to 35 days in the IRBT group was significantly lower than that in the NBT group, and the BW from 7 to 49 days was lower than that in the HBBT group (p < .05). Compared with untrimmed birds, birds in the IRBT group had lower average daily feed intake (ADFI) from 15 to 21 days, and higher heart percentage and L* value in the breast muscle. The upper beak length at 28 and 49 days of age were longest in untrimmed birds, intermediate in birds in the HBBT group, and shortest in the IRBT groups (p <.05). No evidence was found that HBBT caused changes in performance, behavior, carcass traits, organ percentages, and meat quality except for lower change in spleen percentage. Taken together, IRBT had more influence at inhibiting early BW, ADFI, and upper beak length than HBBT in the local broiler breed.     

Whole pearl millet feeding does not impair performance and nutrient digestibility in 28-day-old broiler chickens

The effects of varying inclusion levels of whole grain millet in millet–soya bean-based diets on growth performance, gizzard development, digesta characteristics and nutrient digestion in broiler chicken were investigated. Starter (0–14 days) and grower (15–28 days) broiler chicken diets containing pearl millet at 500 and 540 g/kg diet, respectively, were formulated. The diets comprised of 0%, 20%, 40%, 60%, 80% and 100% of millet incorporated as whole grain. One-day-old unsexed Arbor Acres Plus chicks (n = 540) were allotted to the experimental diets in a completely randomized design with the diets and water provided ad libitum for 28 days. Each treatment was replicated seven times, and each replicate had 12 chicks. Results showed that daily live weight gain and feed conversion ratio of chickens on the whole millet grain diets compared favourably with chicken on the control in both starter and grower phases, while feed intake reduced quadratically (p < .05) with increased whole grain millet levels in the starter phase. Morphological and structural characteristics of the gizzard and small intestine and intestinal digesta pH and viscosity were also unaffected (p > .05) by whole grain millet inclusion levels. However, the weight of intact millet grain in gizzard increased linearly (p < .001) with whole grain millet inclusion in the diets. Dietary whole grain millet inclusion also consistently lowered (p < .05) jejunal and ileal maltase and sucrase activities, but did not influence (p > .05) pancreatic amylase activity. Ileal crude protein and starch digestibility increased, while ileal energy digestibility decreased significantly (p < .05) with whole grain millet inclusion. Whole grain millet inclusion in broiler starter and grower diets up to 500–540 g/kg did not negatively impact on broiler chicken performance.     

Effects of feeding frequency on meat quality traits and Longissimus muscle proteome in finishing pigs

Sixty‐four barrows with an initial body weight of 59.8 ± 2.1 kg were allocated to one of the two feeding frequency regimes (had free access to diet and fed two meals per day). Pigs had free access (FA) to feed were fed on an ad libitum basis during the 8‐week experimental period. Pigs fed twice daily (M2) were allowed to consume their meals in 2 h. Pigs fed twice daily had lower average daily feed intake (p < 0.01) and average daily gain (p < 0.1), but a greater G:F (p < 0.05) than FA pigs. Lower perirenal fat deposition, hot carcass weight, intramuscular fat content (p < 0.05) and dressing percentage (p < 0.1) were found in M2 pigs compared with FA pigs. Activities of citrate synthase, β‐hydroxylacyl‐CoA dehydrogenase and lactate dehydrogenase were greater in the Longissimus muscle (LM) of M2 pigs compared with FA pigs (p < 0.05). Proteomic analysis revealed that expression abundances of proteins involved in glucose metabolism, energy production and lipid utilization were upregulated, but expression levels of proteins participating in protein and amino acid metabolism, stress response and redox homeostasis were downregulated in the LM of M2 pigs than those in FA pigs (p < 0.05). In conclusion, the less meal frequency impairs growth rate, has marginal effects on carcass and meat quality traits and affects expression abundances of proteins in the LM of finishing pigs.     

Plantago ovata in broiler chicken nutrition: Performance,carcass criteria,intestinal morphology,immunity, and intestinal bacterial population

In this experiment, the effect of dietary Plantago ovata (PO) on performance, carcass criteria, intestinal morphology, immunity, and intestinal bacterial population of broiler chickens was evaluated. A total of 250 one‐day‐old male broiler chicks (Ross 308) were randomly assigned to five treatments containing 0, 5, 10, 15, or 20 g/kg of PO with five replicate pens and 10 birds in each replicate. Dietary PO increased body weight gain and decreased feed conversion ratio in the finisher period, improving the performance index (p < .05). Dietary treatments had no effects on carcass criteria, but breast meat percentage showed an increasing trend with incremental levels of PO in the diet (p = .069). The length of small intestine, especially jejunum section, as well as the villus height, villus width, villus area, and goblet cell numbers were significantly increased with supplemental PO (p < .05). Humoral and cellular immunity parameters, and oxidation stability of meat were improved due to use of dietary PO (p < .05). Dietary PO decreased the CFU of Escherichia coli, whereas the Lactobacilli population was increased (p = .001). Broken‐line regression revealed that dietary PO at the rate of 10 g/kg may results in the best performance in broiler chickens. This study showed that PO at the level of 10 g/kg could be considered as a beneficial feed additive in broiler diet.     

Different levels of selenomethionine on the meat quality and selenium deposition in tissue of finishing pigs

The aim of the study was to verify the influence of selenomethionine (SM) supplementation on performance, carcass yield, characteristics of meat quality and Se tissue deposition of finishing pigs. A total of 128 hybrid pigs with an average weight of 76 kg were distributed in randomized blocks according to body weight in eight treatments and eight replicates. The experimental treatments were two Se levels from sodium selenite‐SS (0.3 and 0.6 ppm), four Se levels from SM (0.3, 0.4, 0.5 and 0.6 ppm) and two combinations of SS with SM (SS 0.15 + SM 0.15 ppm and SS 0.3 + SM 0.3 ppm) providing 0.3 and 0.6 ppm Se in the diet respectively. The feeds were based on corn and soya bean meal. After 30 days on test, were analysed the performance indices and the pigs were slaughtered at commercial slaughterhouse. The cold carcass yield, the physicochemical characteristics of the loin meat and the Se content in muscle and liver were evaluated. There was no significant difference in performance indices (p > .05); however, there was a linear effect on the increase in pig carcass yield by increasing SM (p < .05). The use of SM solely or combined with SS provided higher Se deposition in muscle compared to SS (p < .05). The highest Se deposition in muscle occurred for SM at 0.4 ppm (p < .05). The SS provided higher Se deposition in liver (p < .05). The SM presented best results for meat quality compared to other sources (p < .05). The level of 0.4 ppm Se promoted the best results for the indices of yellow, luminosity, cooking loss and pH (p < .05). The use of SM at any level promotes higher oxidation stability of pig meat (p < .05). The supplementation of SM at a level of 0.4 ppm promotes better physicochemical characteristics and higher Se deposition on swine meat.     

Physiological and health‐related response of broiler chickens fed diets containing raw,full‐fat soya bean meal supplemented with microbial protease

A 2 × 3 factorial study (protease: 0 or 1,5000 PROT/kg and raw full‐fat soya bean meal [RSBM] replacing the commercial SBM at 0, 45 and 75 g/kg of diet) was conducted to examine the performance of broilers. Phytase (2000 FYT/kg) was uniformly added to each diet, each also replicated six times, with eight birds per replicate. Birds were raised in climate‐controlled rooms using sawdust as the bedding material and offered starter, grower and finisher diets. Feed intake (FI) and body weight gain (BWG) were reduced (p < .05) due to increasing levels of RSBM, but feed conversion ratio (FCR; 0–35 days) was unaffected. Over the first 24 days, neither RSBM nor protease supplementation affected (p > .05) mortality, footpad dermatitis or intestinal lesions in birds. At day 24, the weight, length, width and strength of tibia bone were reduced in chickens that received an elevated level of RSBM (75 g/kg of diet), but this was not significant at day 35. At day 24 (p < .05) and 35 (p < .01), Ca concentration in the litter was reduced when the RSBM level was increased in the diet, but P content was not affected. On days 24 (p < .05) and 35 (p < .01), the N content in litter was also increased with increase in dietary RSBM. Protease supplementation increased (p < .05) the uric acid concentration in the litter (at day 35), but the reverse was the case for ammonia concentration. Overall, the results of this study indicate that there are no major health‐related risks, associated with the replacement of commercial SBM with RSBM (≤25%) in broiler diets.     

Influence of dietary rapeseed meal levels on growth performance,organ health and standardized ileal amino acid digestibility in meat ducks from 15 to 35 days of age

This study was conducted to investigate the effects of dietary rapeseed meal (RSM) inclusion levels on growth performance, organ health and standardized ileal amino acid digestibility (SIAAD) in meat ducks from 15 to 35 days of age. Six hundred and eighty 15‐days‐old ducks were randomly allotted to five treatments based on body weight. Five isonitrogenous and isoenergetic diets were formulated on a digestible amino acid basis by replacing 0% (the control), 25%, 50%, 75% and 100% (based on fresh) of protein from soya bean meal (SBM) with protein from RSM. The corresponding levels of RSM in experimental diets were 0%, 6.66%, 13.32%, 19.98% and 26.64% respectively. With increasing dietary RSM levels, body weight (BW) and average daily gain (ADG) linearly decreased (p < 0.001), whereas feed‐to‐gain ratio (F: G) linearly increased (p = 0.0078). Ducks fed the diets with 13.32% or more RSM had significantly lower (p < 0.05) BW, ADG and ADFI, or higher F: G than ducks fed the control diet. The maximum limit of dietary RSM supplementation was estimated to range from 4.27% to maximize ADG for 15 to 35 days to 11.69% to maintain feed intake for 15 to 35 days on the basis of a broken‐line model. At day35, the 4th primary wing feather length and SIAAD (except for Met, Thr and Val) linearly decreased (p < 0.001), and the thyroid glands weight (% of BW) linearly increased (p < 0.05) with increasing dietary RSM levels. Ducks fed the RSM inclusion diets had significantly lower (p < 0.0001) serum aspartate aminotransferase (AST) and alanine transaminase (ALT) activities than ducks fed the control diet. These results suggested that the maximum limit of dietary RSM containing 7.57 μmol/g glucosinolates was estimated to be 4.27% to avoid growth reduction.     

Effects of chlorogenic acid-enriched extract from Eucommia ulmoides Oliver leaf on growth performance and quality and oxidative status of meat in finishing pigs fed diets containing fresh or oxidized corn oil

To investigate the effects of chlorogenic acid-enriched extract (CGAE) from Eucommia ulmoides Oliver leaf on growth performance and quality and oxidative status of meat in pigs fed diets containing fresh or oxidized corn oil, a total of 180 barrows (initial body weight: 81.6 ± 2.08 kg) were randomly allocated into 6 diet treatments (5 replicate pens per treatment and 6 barrows per pen) in a 2 × 3 factorial design with corn oil (fresh or oxidized corn oil at 5% inclusion of diet) and CGAE (0, 500 or 1,000 mg/kg of diet containing fresh or oxidized corn oil) as main factors. The experiment lasted for 6 weeks. Dietary oxidized oil reduced average daily gain (ADG, p < .05) and average daily feed intake (ADFI, p < .01) of pigs and pH₂₄ (p < .05), total antioxidant capacity (T-AOC, p < .01), glutathione peroxidase (GPx, p < .05) and sarcoplasmic reticulum Ca²⁺-ATPase (SERCA, p < .05) activities in meat and increased drip loss (p < .01), cooking loss (p < .05), malondialdehyde (p < .01) and carbonyl (p < .01) contents and mRNA expression of superoxide dismutase 1 (SOD1, p < .05) in meat. Dietary CGAE supplementation at 1,000 mg/kg increased (p < .05) ADG and ADFI of pigs and pH₂₄, T-AOC, T-SOD, GPx and SERCA activities and mRNA expression of SOD1 in meat and reduced (p < .05) drip loss, cooking loss, carbonyl and malondialdehyde contents in meat. No interaction effects between oxidized corn oil and CGAE were found in pigs. Overall, dietary CGAE supplementation at 1,000 mg/kg improved growth performance and quality and oxidative status of meat in pigs subjected or not to oxidative stress induced by dietary oxidized oil.     

Effect of gut stress induced by oxidized wheat gluten on the growth performance,gut morphology and oxidative states of broilers

This study was to investigate the effect of oxidized wheat gluten (OG) on growth performance, gut morphology and its oxidative states of broilers. One hundred and eighty‐day‐old male broilers (10 chicks/pen) were randomly allocated into three dietary treatments: control diet (CON), diet with 8% wheat gluten (WG) and diet with 8% OG with six pens/treatment. Body weight (BW) (21 and 35 days) and average daily gain (ADG) (1–21 days and 22–35 days) decreased (p < .05) and feed conversion ratio (FCR) (1–21 days and 22–35 days) increased (p < .05) in OG treatment. Feed intake (FI) decreased (p < .05) in WG and OG treatments during 22–35 days. However, FI was not influenced by dietary treatments during 1–21 days (p > .05). The OG‐fed broilers had a lower faecal pH value (p < .05) and higher faecal moisture content (p < 05) at 14, 21, 28 and 35 days. Villus height, crypt depth and V/C value were not different (p > .05) among treatments at 21 and 35 days. Lipid peroxidation (LPO) (21 and 35 days) and malondialdehyde (MDA) (35 days) content in crop of OG treatment increased (p < .05). Oxidized glutathione (GSSG) (21 days), LPO (21 and 35 days) and MDA (21 and 35 days) content in ileum of OG treatment increased (p < .05). The reduced glutathione/oxidized glutathione (GSH/GSSG) (21 days) and (GSH) (35 days) in ileum of OG treatment decreased (p < .05). The present findings indicate that OG might be a stressor for broiler gut, which could induce oxidative stress both in crop and in ileum, and the diarrhoea as well. The growth performance of broiler was consequently depressed.     

鱼精粉在肉鸡日粮中替代进口鱼粉的效果

选用ＡＡ肉鸡进行试验，试验在生产后期进行，试验分为两组：对照组（含有３％的秘鲁鱼粉）和试验组（含有３％的鱼精粉），两组的营养水平接近。试验组平均日增重为４７．１８ｇ，对照组为４７．０６ｇ；试验组的料肉比为２．６８４，对照组为２．７４５。两者的重要生产性能指标接近，差异不显著。试验结果表明，在生长后期的肉鸡日粮中，使用鱼精粉替代进口鱼粉并不影响试验鸡的生产性能。     

Effects of dietary energy level on growth performance,blood parameters and meat quality in fattening male Hu lambs

This experiment was conducted to investigate the effects of different dietary energy levels on growth performance, slaughter traits, meat quality and blood biochemical parameters in fattening male Hu lambs. Sixty lambs were fed five iso-protein diets which contained different levels of metabolizable energy in a completely randomized design for 70 days. At the end of study, fifteen lambs were harvested for further study. With the increase in dietary energy level, the daily weight gain and dry matter intake extremely increased (p < .001), and feed conversion ratio decreased significantly (p < .01). The live weight before slaughter (LWBS) and carcass weight had a significant increase (p < .05), non-carcass fat ratio and routine indexes of meat quality had no significant difference. Almost no effect was observed for the amino acid profile except for glycine concentration decreased (p < .05) in longissimus dorsi (LD) muscle. The concentrations of C17:0, C18:3n-3 and n-3 PUFA (p < .01) significantly decreased with the increasing dietary energy levels, and the ratio of ∑n-6/∑n-3 (p < .01) increased, whereas the concentrations of C18:1n-9t (p < .05) decreased in LD muscle and C18:1 (p < .01) increased in biceps femoris (BF) muscle. There were no obviously differences for diameter, area and density of muscle fibres. The relative expression of MyHC-IIa and MyHC-IIx decreased significantly (p < .05) in BF muscle, and the relative expression of MyHC-IIa displayed an obviously decreasing trend (p < .10) in LD muscle. These results suggest that increasing the dietary energy level can improve the growth performance and slaughter traits, and influence meat quality and fatty acid profiles in different muscle tissues of fattening male Hu lambs. These results provide a theoretical basis for developing Hu sheep nutritional standards and designing feed formulations.