Effects of xylanase supplementation on growth performance,nutrient digestibility,blood parameters,fecal microbiota,fecal score and fecal noxious gas emission of weaning pigs fed corn‐soybean meal‐based diet

This study was conducted to evaluate the effects of xylanase supplementation on nutrient digestibility, growth performance, blood parameters, fecal microflora shedding, fecal score and fecal noxious gas emission of weaning pigs fed corn‐soybean meal based diet. A total of 150 weaning pigs with an average initial body weight (BW) of 7.85 ± 0.93 kg were randomly allocated to three treatments based on BW and sex (10 replicate pens with five pigs, two gilts and three barrows) were used in this 42‐day trial. Dietary treatments were: (1) CON, basal diet; (2) X1, basal diet +0.005% xylanase; (2) X2, basal diet +0.01% xylanase. The xylanase supplementation linearly increased (P < 0.05) average daily gain (ADG), and gain : feed ratio (G:F) from days 29 to 42 and the in overall period, dry matter, nitrogen and energy digestibility, and fecal Lactobacilli counts, and linearly decreased (P < 0.05) blood urea nitrogen (BUN) concentration, fecal NH₃ and H₂S emission. Additionally, at weeks 5 and 6, there was a linear decrease in fecal score with xylanase supplementation. In conclusion, dietary supplementation of xylanase improved growth performance, nutrient digestibility, shifted microbiota by increasing fecal Lactobacillus counts, decreased BUN concentration, fecal score, and fecal NH₃ and H₂S emission in weaning pigs.     

Developmental stages of the blue‐breasted quail (Coturnix chinensis)

Chickens and Japanese quail (Coturnix japonica) have traditionally been the primary avian models in developmental biology research. Recently, the blue‐breasted quail (Coturnix chinesis), the smallest species in the order Galliformes, has been proposed as an excellent candidate model in avian developmental studies owing to its precocious and prolific properties. However, data on the embryonic development of blue‐breasted quail are scarce. Here, we developed a normal developmental series for the blue‐breasted quail based on developmental features. The blue‐breasted quail embryos take 17 days to reach the hatching period at 37.7°C. We documented specific periods of incubation in which significant development occurred, and created a 39‐stage developmental series. The developmental series for the blue‐breasted quail was almost identical to that for chickens and Japanese quail in the earlier stages of development (stages 1–16). Our staging series is especially useful at later stages of development (stages 34–39) of blue‐breasted quail embryos as a major criterion of staging in this phase of development was the weight of embryos and the length of third toes.     

Effect of low‐ or high‐CP diet with cold‐pressed oil supplementation on growth,immunity and antioxidant indices of growing quail

This study was to investigate the effect of dietary protein levels and supplementation with two cold‐pressed oils on the performance, immunity and antioxidant indices of growing Japanese quails. A 3 × 4 factorial experiment, using 3 dietary crude protein (CP) levels (22%, 24% and 26%) and 4 supplemental herbal oils levels: control without additives, 250 mg marjoram (Mar), 250 mg thyme (Thy) and 125 mg Mar + 125 mg Thy per kg diet. A total of 720 unsexed, 7‐day‐old quail chicks were randomly distributed into twelve treatment groups (4 replicates per group of 15 chicks in each). The live body weight (LBW) on 42 days and body weight gain (BWG) from 7 to 42 days were significantly improved (p < 0.01 and 0.05) in chicks fed 24% or 26% CP compared with those of the 22% CP group. The groups fed diets supplemented with Mar or in combination with Thy oil exhibited significantly better LBW, BWG and feed conversion ratio (FCR) than the control at all periods except BWG from 21 to 42 days and FCR from 7 to 21 days were not significant. Feed intake was gradually decreased with increasing dietary CP level or adding herbal oils during the periods 21–42 and 7–42 days of age. Plasma triglycerides, cholesterol, total lipids and malondialdehyde were decreased by cold‐pressed oils supplementation, but the activity of reduced glutathione and superoxide dismutase was increased (p < 0.01) compared with the control. In conclusion, quails fed a diet containing 24% or 26% CP or diets supplemented with Mar or Thy oils or both exhibited improvement in the performance, lipid profile, immunity and antioxidant capacity without any detrimental impacts on the other studied parameters.     

Influence of partial replacement of ground wheat with whole wheat and exogenous enzyme supplementation on growth performance,nutrient digestibility and energy utilization in young broilers

This study investigated the influence of pre‐pelleting inclusion of whole wheat (WW) and exogenous enzyme supplementation on growth performance, coefficient of apparent ileal nutrient digestibility (CAID) and apparent metabolizable energy (AME) in broilers fed wheat‐based pelleted diets. A 2 × 3 factorial arrangement of treatments was used with two methods of wheat inclusion [622 g/kg ground wheat (GW) and 250 g/kg WW replaced GW (wt/wt) pre‐pelleting (PWW)] and three enzymes (xylanase, phytase and xylanase plus phytase). A total of 288, one‐day‐old male broilers (Ross 308) were individually weighed and allocated to 36 cages (8 broilers/cage), and the cages were randomly assigned to the six dietary treatments. Birds fed PWW diets gained more (p < 0.05) weight than those fed GW diets. There was no effect (p > 0.05) of WW inclusion on feed intake (FI). Phytase alone increased (p < 0.05) FI compared to xylanase or the combination. Whole wheat inclusion increased (p < 0.05) the gain‐to‐feed ratio (G:F). Feeding xylanase plus phytase and phytase‐added diets resulted in the greatest and lowest G:F, respectively, with xylanase supplemented diets being intermediate. Birds fed PWW diets had greater (p < 0.05) relative gizzard weights than those fed GW diets. There was no effect (p > 0.05) of WW inclusion on the CAID of nitrogen (N), starch and fat. Combination of xylanase and phytase resulted in greater (p < 0.05) digestibility of N, starch and fat than that of individual additions. Feeding PWW diets resulted in greater (p < 0.05) AME values than GW diets. Combination of xylanase and phytase increased (p < 0.05) the AME compared to the diets with individual additions of xylanase or phytase. The current results suggest that the influence of pre‐pelleting WW inclusion and exogenous enzymes on nutrient digestibility and broiler performance is not additive.     

Impact of restricting feed and probiotic supplementation on growth performance,mortality and carcass traits of meat‐type quails

The objective of this study was to evaluate the effects of quantitative feed restriction, along with dietary supplementation with a probiotic blend (Protexin) as a natural growth promoter, on the performance, water consumption, mortality rate and carcass traits of meat‐type quails. A total of 250 1‐day unsexed quails were randomly allocated to five equal groups in a completely randomized design. The first group (A) fed a basal diet without any restriction (24 hr/day); the second group (B1) fed the basal diet for 20 hr/day; the third group (B2) fed the basal diet enriched with probiotic (0.1 g/kg diet) for 20 hr/day; the fourth group (C1) fed the basal diet for 16 hr/day; and the fifth group (C2) fed the basal diet enriched with probiotic (0.1 g/kg diet) for 16 hr/day. Birds were fed ad‐libitum from 0–14 days of age, and then the feed restriction regimes started from 14 till 28 days of age. Results showed that quails in the control‐group consumed more feed and water than the other treatment groups (p < .01), however their body weights did not differ (p > .05) compared with the other treated groups. The best feed conversion values were achieved in quails supplemented with probiotic blend (B2 and C2) in comparison with the other groups (p < .01). Feeding probiotic had a positive effect on bird health which reduced the mortality rate. Further, mortality rate was significantly reduced (p < .05) by feed restriction, with or without probiotic supplementation. No carcass parameters were significantly affected (p > .05) by treatments. Our results show that quail could be reared under a feed restriction system, for 4–8 hr daily, along with dietary supplementation of probiotic as growth promoter for better growth performance.     

Characterization and expression of non‐polymorphic liver expressed antimicrobial peptide 2: LEAP‐2 in the Japanese quail,Coturnix japonica

Liver‐expressed antimicrobial peptide 2 (LEAP‐2) is a cationic peptide that plays an important role in innate immunity for host defense. The aim of this study was to characterize the LEAP‐2 gene in the Japanese quail (Coturnix japonica). Japanese quail LEAP‐2 (CjLEAP‐2) was identified from the Japanese quail draft genome database by a local BLAST analysis using chicken LEAP‐2 (GgLEAP‐2). The exon‐intron structure of CjLEAP‐2, analyzed from three quails, is composed of three exons, as is the chicken LEAP‐2 homolog (GgLEAP‐2). An analysis of the coding sequence revealed that CjLEAP‐2 is 231 bp long, like GgLEAP‐2, and 93% identical to GgLEAP‐2 at the nucleic acid level. The predicted amino acid sequence of CjLEAP‐2 contained the liver‐expressed antimicrobial peptide 2‐precursor domain and four cysteine residues characteristic of the LEAP‐2 protein. The amino acid sequence of the mature peptide of CjLEAP‐2 was 100% identical to that of GgLEAP‐2. We confirmed that CjLEAP‐2 was transcribed in at least seven tissues, including the digestive system. Additionally, the mature peptide region of CjLEAP‐2 exhibited no polymorphisms in 99 quails from six strains. Taken together, these findings indicate that CjLEAP‐2 is non‐polymorphic and therefore, it likely plays an important role in the innate immunity of quail as it does in chicken.     

Skeletal development in blue‐breasted quail embryos

The blue‐breasted quail (Coturnix chinensis), the smallest species of quail with short generation interval and excellent reproductive performance, is a potential avian research model. A normal series of skeletal development of avian embryos could be served as a reference standard in the fields of developmental biology and teratological testing as well as in the investigation of mutation with skeletal abnormalities and in the study of the molecular mechanisms of skeletal development through genome manipulation. Furthermore, ossification sequence shows a species‐specific pattern and has potential utility in phylogeny. However, data on the skeletal development of blue‐breasted quail embryos are scarce. Here, we established a series of normal stages for the skeletal development of blue‐breasted quail embryos. Cartilage and ossified bones of blue‐breasted quail embryos were stained blue and red with Alcian blue 8GX and Alizarin red S, respectively. The time and order of chondrification and calcification of their skeletons were documented every 24 hr from 3 to 17 days of incubation, and a 15‐stage series of skeletal development was created. Moreover, a comparative study with the Japanese quail (Coturnix japonica) demonstrated that ossification sequence differed significantly between these two species.     

Effects of a rice diet and phytase addition on growth performance,tissue weights,phosphorus and nitrogen retention,and on liver threonine dehydrogenase,malic enzyme and fatty acid synthase activities in broiler chicks

This experiment was conducted to clarify the nutritional functions of rice and phytase addition for broiler chicks. Thirty‐six 7‐day‐old male chicks (ROSS 308 strain) were assigned to one of the four treatment groups: corn‐ or rice‐based diet groups and each diet with added phytase (2000 phytase units/kg diet) groups (corn + P or rice + P groups). The non‐phytate phosphorus (npP) content in the diets with added phytase was approximately half of the requirement. Body weight gain and feed intake in the rice group was significantly higher than those in the corn group. Breast and thigh muscle weights and nitrogen retention in the rice group were significantly higher than that in the corn group. Although the efficiency of phosphorus retention (%) in the corn + P group was significantly higher than that in the corn group, no significant difference was observed between the rice and rice + P groups. Liver threonine dehydrogenase activity in the corn group was significantly higher than in the other three groups. These results indicate that rice is superior to corn as a starter diet in broiler chicks, and that phytase action in the rice‐based diet was less than that in the corn‐based diet.     

Effect of dietary supplementation of hemp seed (Cannabis sativa L.) on meat quality and egg fatty acid composition of Japanese quail (Coturnix coturnix japonica)

This study was conducted in two separate experiments. Experiment I was conducted to investigate the effects of hemp seed (HS) on meat quality traits, and experiment II was designed to determine egg fatty acid (FA) composition in Japanese quail (Coturnix coturnix japonica). In experiment I and experiment II treatments, groups were as follows: (i) control (not included HS0), (ii) 5% HS inclusion to diets, (iii) 10% HS inclusion to diets and (iv) 20% HS inclusion to diets. In experiment I, a total of 192 7‐day‐old‐quail were fed with HS diets for 5 weeks, and end of the experiment I, a total of 64 quail (16 each) slaughtered and meat samples were analysed for meat colour, pH, cooking and thawing loss and FA composition. In experiment II, a total of 120 8‐week‐old laying quail were fed with experimental diets for 6 weeks and egg FA composition were determined. Breast meat cooking loss was significantly lower in 20% supplemented group (p < 0.01). Hemp seed inclusion to diets caused a linear and cubic increase in redness (a*) of hip meat (p < 0.01). Palmitoleic and oleic FAs were decreased with HS addition in breast meat (p < 0.05); however, linoleic and linolenic acid contents of meat were linearly increased (p < 0.01). In experiment II, the linoleic and linolenic FA contents of egg samples were linearly increased with increasing the dietary HS ratio (p < 0.01). Hemp seed addition was provided lower palmitoleic and oleic FAs in quail eggs (p < 0.05). In conclusion, HS supplementation to quail diets may increase quail meat redness and meat and egg yolk omega‐3 FA content and decrease cooking loss of quail meats.     

Effect of an organic acid blend and phytase added to a rapeseed cake‐containing diet on performance,intestinal morphology,caecal microflora activity and thyroid status of broiler chickens

The experiment was carried out on 96 female broilers, allocated to eight groups of 12 birds kept in individual cages. Two basal wheat‐ and soyabean meal‐based diets containing 150 g/kg of rapeseed expeller cake were formulated, differing in the level of P: 7.1 g/kg in diet H or 5.9 g/kg in diet L. Rapeseed cake supplied 3.15 μmol alkenyl glucosinolates per gram of diet. The eight treatments were: basal diets only, basal diets + phytase (1000 U/kg), basal diets + organic acid blend (OA, 6 g/kg), or basal diets + both additives. Diets were fed from day 8 to 28 of life. The results showed that the lower dietary P content and OA supplementation did not significantly affect feed intake or BWG, while both increased (p < 0.001) after phytase supplementation. Tibia ash content as well as tibia ultimate strength were lower (p < 0.001) in birds fed diets L compared with diets H, and increased (p < 0.01) with phytase supplementation of diet L, while OA had no influence on either parameter. Dietary P levels and OA supplementation had no influence on the pH of gut digesta, but the pH of jejunal digesta increased following phytase supplementation (p < 0.01). Morphological measurements of the small intestinal mucosa of chicks indicated that OA added to diet L depressed villi height (p < 0.001) and crypt depth (p < 0.001); both parameters increased after phytase supplementation (p < 0.01). The lower total SCFA as well as acetic, propionic and butyric acid concentrations in caecal digesta indicated lower activity of caecal microflora in birds fed diets L compared with H. OA supplementation had no influence, while phytase supplementation increased the concentration of acetic acid in caecal digesta. Supplementation of diets with either phytase or OA increased thyroid weight by 16% (p < 0.01) and 11% (p < 0.05) respectively. The increase in thyroid weight because of phytase supplementation was greater at the lower dietary P level, and the greatest when both phytase and OA were added to the diet.     

Growth performance,carcass traits and meat quality of yellow‐feathered broilers fed graded levels of alfalfa meal with or without wheat

The effects of 0, 40 and 80 g/kg alfalfa meal on growth performance, carcass traits and meat quality of Chinese yellow‐feathered broilers fed diets containing or lacking wheat (0 or 200 g/kg) as part of the energy source, were examined using random design with a 2 × 3 factorial arrangement of treatments. Dressing percentage and semi‐eviscerated proportion were lower, and meat color a* (redness) value was higher in birds fed diets containing wheat than diets lacking wheat (P < 0.05). Drip loss was reduced by the addition of alfalfa meal to diets containing or lacking wheat (P < 0.05). Average sensory score of breast meat was higher in chickens fed corn‐based diets than in those fed wheat (P < 0.05). Meat from those supplemented with 40 g/kg alfalfa meal had better taste than the other two levels (P < 0.05). The inclusion of wheat significantly reduced the activities of creatine kinase and calpain of breast muscle (P < 0.05). In conclusion, Chinese yellow‐feathered broilers fed diets containing wheat had better meat color and lower drip loss than those fed the diets without wheat, and adding 40 g/kg alfalfa meal generally improved meat quality and taste.     

The effect of different high‐fat diets on erythrocyte osmotic fragility,growth performance and serum lipid concentrations in male,Japanese quail (Coturnix coturnix japonica)

Poultry diets are formulated with additional animal fat or vegetable oils to improve growth rate and feed conversion efficiency. High‐fat diet feeding in rats and fish has been shown to result in alterations in the phospholipid composition and cholesterol content of the erythrocyte membrane, in turn affecting erythrocyte osmotic fragility. In contrast, the few studies performed using high‐fat diet feeding in avian species show no changes in erythrocyte osmotic fragility. This study made use of the Japanese quail as no data exists on investigation of this species with respect to high‐fat diet feeding and erythrocyte osmotic fragility. Fifty‐seven male quail were randomly divided into six groups and fed either a standard diet (commercial poultry feed) or one of five high‐fat diets (commercial poultry feed with 22% of either coconut oil, lard, palm oil, soya bean oil or sunflower oil on a weight/weight basis) for 12 weeks. All birds on the high‐fat diets were significantly heavier (p < 0.05) after the 12‐week feeding period, than when commencing the dietary intervention. Serum triglyceride concentrations of birds in all high‐fat diet groups were significantly lower (p < 0.05) than birds in the standard diet group, whereas only birds in the palm oil group had significantly lower (p < 0.05) serum cholesterol concentrations compared to the standard diet group. Fragiligrams of erythrocytes from birds in the various dietary groups were similar. High‐fat diet feeding with different types of additional fat did not affect the osmotic fragility of the quail erythrocytes. Feeding quail high‐energy diets of varying degrees of fatty acid saturation was well tolerated and did not seem to affect the overall health status of the birds. Resistance of avian erythrocytes to modification by excess dietary fat may be a general characteristic of avian erythrocytes.     

Effect of dietary supplementation of calcium butyrate on growth performance,carcass traits,intestinal health and pro‐inflammatory cytokines in Japanese quails

The objective of the present study was to evaluate the potential effect of dietary calcium butyrate on growth performance, carcass traits and gut health in Japanese quails. In total, 320 one‐day‐old Japanese quails were randomly assigned to 4 equal treatments, with 8 replicates of 10 Japanese quails, for 4 weeks. The Japanese quails in control treatment were fed control diet whereas in the other treatments the Japanese quails were fed diet supplemented with calcium butyrate at 0.3, 0.5 and 0.7 g/kg diet. Data concerning performance measurements were recorded weekly. In addition, eight Japanese quails (one/replicate) from each treatment were selected randomly for serum collection to measure pro‐ and anti‐inflammatory cytokines. Pooled faecal samples from each replicate of each treatment were also collected at three time points (0, 2 and 4 weeks) for count E. coli and C. perfringens. The results showed that after 7 days of the experimental period, Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg showed a greater (p < .05) body weight and a favourable (p < .05) feed conversion ratio than the other treatments. Moreover, serum superoxide dismutase and catalase activities were increased (p < .05) in Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg. Calcium butyrate supplementation at 0.7 g/kg was associated with reduction (p < .05) in TNF‐α, IL‐6 and IL1‐β, while IL‐10 was increased (p < .05). In addition, after 2 weeks of calcium butyrate supplementation, a reduction (p < .05) in E. coli and C. perfringens counts was observed in excreta of Japanese quails fed 0.5 and 0.7 g calcium butyrate/kg diets. It is concluded that calcium butyrate supplementation improves body weight gain, reduces E. coli and C. perfringens counts and has anti‐inflammatory/anti‐oxidant effect in Japanese quails.     

Effect of soaking,fermentation with lactobacillus and enzyme treatment on nitrogen‐corrected apparent metabolizable energy values of wheat in cockerels and quails

An experiment was carried out to determine nitrogen‐corrected apparent metabolizable energy (AMEn) values of processed wheat products with two levels of enzyme (0 and 0.5 g/kg) and five processing methods [control (C), water‐soaking for 12 h (SO12h), 24 h (SO24h) and 48 h (SO48h) and fermentation with lactobacillus (FL)] in two species of poultry (cockerel and Japanese quail). In this study, each processing method group had six replications with two cockerels or four quails per replication. The results showed that the calculated AMEn values of processed wheat by different methods were as follows: C‐12.61 and 12.60; SO12h‐12.75 and 12.73; SO24h‐12.80 and 12.79; SO48h‐12.97 and 12.96; and FL‐13.36 and 13.33 MJ/kg for cockerels and quails, respectively, indicating that fermentation improved AMEn values compared with the others. The mean AMEn of processed wheat with enzyme (13.12 MJ/kg) was significantly higher than that of processed wheat without enzyme (12.64 MJ/kg). However, there were no significant differences in the AMEn of processed wheat between cockerels and quails. The interaction between species and levels of enzyme in AMEn values was not significant. There was no significant difference (p > 0.05) in three‐way interactions among species, levels of enzyme and wheat processing methods for AMEn values. In conclusion, the results of the experiment suggest that the FL was more effective processing method of wheat to obtain high level of AMEn values than the others, and the combination of enzyme and processing methods can increase the AMEn values compared with processing methods alone.     

Performance and nutrient digestibility in growing pigs fed wheat dried distillers’ grain with solubles‐containing diets supplemented with phytase and multi‐carbohydrase

Effect of supplementing wheat dried distillers’ grain with solubles (DDGS)‐containing diet with enzymes on nutrient utilization by growing pigs was evaluated in two experiments. In Experiment 1, 60 pigs weighing ~30 kg were fed five diets that included a corn‐based diet (Control), Control with 10% wheat DDGS (DDGS‐PC), DDGS‐PC without inorganic P source (DDGS‐NC), and DDGS‐NC plus phytase alone or with multi‐carbohydrase for 4 weeks to determine average daily gain (ADG), average daily feed intake (ADFI) and gain‐to‐feed ratio (G:F). In Experiment 2, 30 barrows weighing 22 kg were fed five diets fed in Experiment 1 to determine nutrient digestibility and retention. Pigs fed DDGS‐PC and Control diets had similar ADG and G:F. The ADG and G:F for DDGS‐PC diet were higher (P < 0.05) than those for DDGS‐NC diet. Phytase improved (P < 0.05) ADG, G:F, total tract P digestibility and P retention by 6.6, 8.7, 86.0 and 85.5%, respectively. Addition of multi‐carbohydrase to phytase‐supplemented diet did not affected growth performance, but reduced (P < 0.05) P retention. In conclusion, inclusion of 10% wheat DDGS in growing pig diet may not affect growth performance of growing pigs. Phytase supplementation to wheat DDGS‐containing diet can eliminate the need for inorganic P supplement in pig diets.     

Semen characteristics and biochemical composition of cloacal foam of male Japanese quails (Coturnix coturnix Japonica) fed diet incorporated with selenium

An attempt was made to investigate the effect of dietary selenium (Se) on physical and cloacal gland size, foam production, biochemical composition of foam and semen biochemical characteristics of male Japanese quail (Coturnix coturnix Japonica). Two hundred twenty‐five (225)‐day‐old male Japanese quail were randomly distributed to three dietary treatment groups for a period of 20 weeks. Each treatment comprised of three replicates, each containing 25 chicks. Three experimental diets were supplemented with 0, 0.5 and 1.0 mg Se/kg (T₁, T₂ and T_3, respectively), and diet T₁ was considered as control. Sodium selenite was used as the source of selenium. All the birds were provided with feed and water ad libitum. Cloacal foam characteristics, that is cloacal gland index and foam weight, were significantly higher in T₂ group. However, body weight, frequency of foam discharge and testes weight (left and right) did not differ significantly (p > 0.05). Physical characteristics of semen, that is semen volume and sperm concentration, did not differ (p > 0.05) among the Se‐treated groups. The sperm motility, live–dead count and abnormality improved significantly (p < 0.05) in 0.5 mg/Se‐supplemented group compared to 0 or 1.0 mg/Se‐supplemented groups. Similarly, fertility and hatchability percentages were higher (p < 0.05) in 0.5 mg/Se‐supplemented group than in control or 1.0 mg/Se‐supplemented counterparts. The biochemical characteristics of foam in terms of total protein, acid phosphatase (ACP) and nitric oxide did not differ (p > 0.05), while the concentration of glucose was higher (p < 0.05) in 0.5 mg/Se‐supplemented diet. On the other hand, alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were lower (p < 0.05) in 0.5 mg/Se‐supplemented group compared to control or 1.0 mg/Se‐supplemented groups. From this study, it was concluded that supplementation of 0.5 mg Se/kg diet was beneficial for foam variables, biochemical composition of foam, semen characteristics and fertility in male Japanese quail.     

Supplementation of L‐glycine and L‐glutamate to Japanese quails from 01 to 36 days of age using the ideal protein concept

Experiment I: T_1‐1 = basal diet with 25% crude protein (CP) + limiting amino acids (LA); T_1‐2 = 20% CP + LA; T_1‐3 = 20% CP + LA + L‐glycine; T_1‐4 = 20% CP + LA + L‐glutamate; T_1‐5 = 20% CP + LA + L‐glycine + L‐glutamate. Experiment II: T_2‐1 = basal diet with 22% CP + LA; T_2‐2 = 20% CP + LA; T_2‐3 = 17.6% CP + LA + L‐glycine; T_2‐4 = 17.6% CP + LA + L‐glutamate; T_2‐5 = 17.6% CP + LA + L‐glycine + L‐glutamate. The reduction of dietary protein based on the concept of ideal protein decreases nitrogen excretion in quails when L‐glycine is added to the diets. Quails fed diets supplemented with L‐glutamate as the non‐specific nitrogen source equivalent to the nitrogen level of the control diet had increased nitrogen excretion. However, quails had reduced nitrogen excretion in both experiments when L‐glycine was added to diets with L‐glutamate. Carcass fat was increased by reducing dietary protein, but fat deposition was reduced by adding L‐glutamate and L‐glycine, or both. The dietary addition of L‐glutamate and L‐glycine in quails based on the ideal protein concept is not necessary (Exp. I). Although the total nitrogen, electrolytic balance and glycine level were adjusted in diets, quails had decreased performance. Therefore, other hypotheses besides protein reduction need to be studied (Exp. II). Protein reduction with supplementation of only limiting essential amino acids does not affect quail performance. Dietary addition of L‐glycine reduces nitrogen excretion.     

Reproductive performance of breeder quails fed diets supplemented with L‐cysteine‐coated iron oxide nanoparticles

The objective of this study was to investigate the effects of L‐cysteine‐coated iron oxide nanoparticles on reproductive performance in breeder quails. The five treatment diets consisted of (i) negative control diet not supplemented with iron, (ii) positive control diet supplemented with 60 mg/kg of Fe₃O₄ and (iii) experimental diets supplemented with 0.6, 6 and 60 mg/kg of L‐cysteine‐coated iron oxide nanoparticles. A total of 100 seven‐day‐old quail chicks were weighed and randomly placed to five groups of five replicate cages. Four quails (one male and three females) were raised in each cage (50 × 15 × 17 cm). Egg production, feed consumption and egg weight were recorded daily and calculated on a hen per day basis. Egg components, fertility, hatchability and day‐old chicks hatched from their eggs were measured at the end of the experiment. The percentage of egg production and egg mass of the 6 mg/kg Fe₃O₄‐Cys NPs group were significantly higher than those of the control groups. Throughout the experimental period, the highest weekly egg weight was recorded for the 60 mg/kg Fe₃O₄‐Cys NPs group. Fertility was improved by diet supplemented with iron, both FeSO₄ and Fe₃O₄‐Cys NPs. The breeder fed Fe₃O₄‐Cys NPs had the highest day‐old chicks weight. The results of this study showed that Fe₃O₄ nanoparticles that were coated by L‐cysteine could improve availability and utilization of iron in diet. Finally, it was proposed that Fe₃O₄‐Cys NPs could be used as feed additives in quails.     

小麦日粮中木聚糖酶和植酸酶对肉仔鸡生长和养分消化率的影响

432只艾维因肉仔鸡用于研究小麦基础日粮中添加木聚糖酶(320FXU/kg)或添加750U/kg植酸酶降低日粮中0.08％的非植酸磷后,对生长性能、日粮表观代谢能、粗蛋白和植酸磷表观消化率的影响。试验结果表明:无论是单一添加木聚糖酶或植酸酶,还是同时添加这两种酶,都能提高1-6周龄肉仔鸡的增重和饲料转化率,降低死亡率。添加木聚糖酶可提高肉仔鸡小麦日粮的表观代谢能2.14％,增加氮的存留量2.58％。750U/kg的植酸酶完全可以降低肉仔鸡小麦日粮中0.08％非植酸磷。添加植酸酶的处理组可提高植酸磷的表观消化率43.25％,减少植酸磷排泄量55.0％。植酸酶和木聚糖酶对全期饲料转化率和植酸磷的表观消化率表现有明显的正互作效应(P<0.05)。