The nutritional effect of <Emphasis Type="Italic">Moringa oleifera</Emphasis> fresh leaves as feed supplement on Rhode Island Red hen egg production and quality

This study aimed to evaluate the potential of Moringa oleifera fresh leaves (MOL) as feed supplement on the performance and egg quality of Rhode Island Red (RIR) hens under the tropical conditions of Yucatan, Mexico. Forty-eight RIR hens were allocated in 12 floor pen replicates each with four birds. Thereafter, the replicates were divided into three groups which were corresponded to ad libitum feed (control), ad libitum feed supplemented with MOL T1 (AL + MOL) and restricted feed amount (20% lower than control) with MOL T2 (RCD + MOL), respectively. T1 (AL + MOL) had higher egg laying rate (71.4% versus 66.6%), higher daily egg mass production (45.4 versus 41.9 g/day), lower feed intake (121.3 versus 127.5 g/day) and better feed conversion ratio (2.8 versus 3.2 g feed:g egg) versus control. T2 / (RCD + MOL) had lower values of body weight, egg laying rate, egg weight and egg mass, and recorded better feed conversion ratio than the control group. The control group recorded a higher percentage of pecked eggs versus T1 and T2 (6.5% versus 1.2% and 2.0 %). Similar intake of MOL (3.1 and 3.4 g DM/day) was recorded in T1 (AL + MOL) and T2 (RCD + MOL). Yolk color was improved significantly in T1 (AL + MOL) than both control and T2 (RCD + MOL), while T2 (RCD + MOL) had eggs with lower yolk and higher albumen percentages than the other two ad libitum groups. The results suggest that MOL could be used successfully as sustainable tropical feed resource for RIR hens.     

Effect of nutrient density on production performance, egg quality and humoral immune response of brown laying (Dahlem Red) hens in the tropics

A study was conducted to evaluate the effect of various concentrations of metabolizable energy (ME) with graded incremental levels of crude protein (CP) and essential amino acids (lysine and methionine) on production performance, egg quality and humoral immune response of Dahlem Red laying hens. Four experimental diets based on maize–soybean meal-deoiled rice bran were prepared. Diet 1 was fed as a control diet containing 2,600 kcal ME/kg, 15% CP, 0.75% Lys and 0.36% Met, and in the other three diets (D2, D3 and D4), concentrations of the above nutrients were increased by 2.5%, 5.0% and 7.5%, respectively. The levels of Ca (3.5%) and available P (0.32) were constant in all the diets. Each diet was offered ad libitum from 28 to 40 weeks of age to eight replicates containing six birds in each replicate. The egg production, egg weight and egg mass (in grams of egg per hen per day) were not affected by increasing the nutrient density up to 7.5% (2,795 kcal ME/kg diet) compared to the control group (2,600 ME/kg diet). However, feed consumption and feed efficiency (in grams of egg per gram of feed) were influenced by the variation in the nutrient density of diets. As the nutrient density increased by 5% (2,730 ME/kg diet), birds consumed significantly (P < 0.001) less feed. The birds in the 7.5% higher density group produced significantly (P < 0.05) higher egg mass per unit feed consumption compared to the control diet. Increasing nutrient density up to 7.5% had no effect on relative weight of albumen, yolk or shell. The Haugh unit, yolk colour and shell thickness were also not affected due to variation in the nutrient density. The humoral immune response measured at 34 and 40 weeks was progressively improved by increasing the nutrient density up to 5%. Increasing the nutrient density beyond 5% in the diet had no further influence on the humoral immune response. Based on the results of the present study, it can be concluded that Dahlem Red laying hens required 2,795 kcal/kg ME, 16% CP, 0.8% lysine and 0.4% methionine for eliciting optimum performance and immune response during 28 to 40 weeks of age.     

Effects of Chinese herbal mixture on performance,egg quality and blood biochemical parameters of laying hens

The aim of the study was to evaluate the effect of Chinese herbal mixture (CHM) in laying hen diets on performance, egg quality and egg nutrition components, as well as selected blood biochemical parameters. A total of 270 Lohmann Brown laying hens, 24 week of age, were randomly distributed into three dietary treatments and fed for 6 week. The CHM was used at the levels of 0%, 0.5% and 1.0% in the diets of the control and two treatment groups respectively. Each dietary treatment was divided into five replicates, comprising of 18 hens each. Hens were housed in a 3‐tier battery system. Feed and water were provided ad libitum. Blood samples and eggs were collected at the end of the experiment. The results showed that dietary treatments did not affect egg weight, mortality, eggshell thickness, albumen height, Haugh units, eggshell‐breaking strength and egg‐shape index. Dietary supplementation of CHM significantly improved (p < 0.05) laying rate and the lowest feed conversion ratio were observed with 1.0% CHM supplementation diets. CHM supplementation decreased (p < 0.05) cracked‐egg rate, egg yolk cholesterol, blood serum levels of cholesterol, triglyceride, low‐density lipoprotein cholesterol (LDL‐C) and alanine aminotransferase (ALT) and increased blood serum levels of high‐density lipoprotein cholesterol (HDL‐C). No differences in serum total protein, serum albumen, serum glucose and aspartate amino transferase (AST) were observed in hens fed CHM. In conclusion, dietary supplementation with CHM improved egg production and egg quality and reduced serum cholesterol concentrations in laying hens. Dietary supplementation of 1.0% CHM in layer diets may be a feasible means of producing eggs with lower cholesterol and higher egg yolk phospholipid contents for health conscious consumers.     

Effect of expanded cottonseed meal on laying performance,egg quality,concentrations of free gossypol in tissue,serum and egg of laying hens

Three hundred and sixty Hy‐Line Brown hens, 40 week of age, were allocated to five treatments, each of which included four replicates of 18 hens. After an expanded process of cottonseed meal (CSM), free gossypol content in CSM was decreased from 1.24 to 0.40 g/kg. The dietary treatments were corn‐soybean meal based diets including 6% CSM and 6%, 8% and 10% expanded cottonseed meal (ECSM). Hens fed 8% ECSM had higher (P < 0.05) laying rate and average egg weight than those fed 6% CSM. The albumen height and Haugh unit in the control group, 6% and 8% ECSM groups were superior (P < 0.05) to other treatments. Hens fed 6% CSM resulted in severe (P < 0.05) egg yolk discoloration. Free gossypol (FG) concentrations in yolk and albumen and tissues of the 6% CSM group were greater (P < 0.05) than those in any ECSM treatments. Hens fed 6% CSM and 10% ECSM had the highest (P < 0.05) FG concentrations in the liver compared with those in the kidney and muscle, and higher (P < 0.05) FG residues in yolk than those in albumen. In conclusion, FG in CSM can be reduced by 68% through an expanded process and ECSM can be available in laying hens at up to 10% of the total diet and an appropriate replacement of soybean meal with ECSM may improve performance in laying hens.     

Tea polyphenols increase the antioxidant status of laying hens fed diets with different levels of ageing corn

This study was conducted to evaluate the effects of ageing corn levels (stored for 4 years) with or without the supplementation of tea polyphenols (TPP) on the performance, egg quality and antioxidant status of laying hens. A total of 288 Lohmann commercial laying hens (63-week-old) were used under a 2 × 4 factorial arrangement with 4 levels of dietary ageing corn (0%, 25%, 50%, or 100%) and 2 levels of TPP (0 and 600 mg/kg) for 8 wk. Dietary ageing corn linearly decreased (P < 0.05) the egg production, serum total antioxidant capacity (T-AOC), liver glutathione peroxidase (GSH-Px) of laying hens, yolk index, yolk colour, 1,1-diphenyl-2-picrylhydrazyl (DPPH) value and the reducing power value of egg yolk, but it linearly increased (P < 0.05) the feed conversion rate, ovary malondialdehyde (MDA) content of laying hens, and the protein carbonyl content of egg yolk. Tea polyphenol supplementation increased (P < 0.05) the serum T-AOC, serum superoxide dismutase (SOD), liver SOD, liver GSH-Px, ovary SOD, GSH-Px, the expression of antioxidant-related genes of laying hens, albumen height, Haugh unit, DPPH value and the majority free amino acids of egg yolk, but it decreased (P < 0.05) the serum MDA content of laying hens, MDA and protein carbonyl of egg yolk. In conclusion, the ageing corn significantly reduced the performance, egg quality, antioxidant status and egg antioxidant capacity of laying hens, while TPP supplementation partially counteracted the adverse effects, especially antioxidant status and egg antioxidant capacity of laying hens.     

Stress parameters and immune response of layers under different cage floor and density conditions

The aim of the experiment was to investigate the effects of cage floor and cage density on stress parameters of laying hens. A total of 162 brown laying hens (Hyline Brown), aged 34 weeks, were used in the experiment. Compact-type battery cages, with three floors, were used. Hens were allocated as one, three or five hens in each of 18 cages to obtain three different cage density groups of 1968, 656 and 393.8 cm² floor area per hen, respectively. The same number of cages with different cage density were allocated to three different battery floors (first floor=top, second=middle, third=bottom) systematically. Values for body weight, mortality rate, egg weight, egg production, egg quality characteristics, egg yolk cholesterol content, the levels of blood plasma corticosterone, serum glucose, total cholesterol and triglycerides, the ratio of heterophils to lymphocytes (H-L ratio), antibody titers, claw length score, foot health score, plumage score and throat skin injuries were taken as indicators of stress. The values for egg weight (P<0.01) at the first floor were greater than the other floor levels. The group with five hens per cage had significantly lower mean estimates (P<0.01) than other groups with respects to body weight (P<0.001), egg production (P<0.001), egg weight (P<0.001) and plumage score (P<0.01), while significantly higher mean estimates for egg albumen index (P<0.01), Haugh unit (P<0.01), serum glucose (P<0.001), and H-L ratio (P<0.001). Serum cholesterol was higher in cages with one hen than that with five hens, whereas plasma corticosterone was lower. Antibody titers in cages with one hen was similar to that with three or five hens; however, those with three hens had higher titers than those with five hens. Values for egg breaking strength, yolk index, egg cholesterol content, and foot health score were not affected by cage density or floor. The results suggest that the allocation of three hens per cage had no measurable effect on health and welfare.     

The impact of phytoestrogen source supplementation on reproductive performance,plasma profile,yolk fatty acids and antioxidative status in aged laying hens

The objectives of this study were to investigate the effects of flaxseeds and/or fenugreek seeds as a source of phytoestrogens in laying feed on productive performance, egg quality, yolk fatty acids, plasma profile and antioxidative status in aged laying hens. A total of 120 Bovans Brown hens at 65 weeks of age were housed individually in laying cages in an open‐sided building under a 16‐hr light: 8‐hr dark lighting schedule. Hens were randomly divided into four experimental treatments (n = 30 each): (a) control (basal diet without any supplementation); (b) 1 g/kg of flaxseeds; (c) 1 g/kg of fenugreek seeds; and (d) combination of 1 g/kg flaxseeds and 1 g/kg fenugreek seeds from 65 to 71 weeks of age. Hen‐day egg production and egg mass were significantly increased by dietary supplementation of flaxseeds and/or fenugreek seeds, while feed intake was not affected; thus, feed conversion ratio was improved (p < 0.05). Weights of egg, albumen, yolk and shell were increased by the dietary treatments. Shell thickness and yolk colour were improved by supplementation of flaxseeds and/or fenugreek seeds. Yolk crude protein was not significantly affected by treatments; however, crude fat and calcium contents in yolk were increased and egg yolk cholesterol content was decreased. Interestingly, dietary supplementation of flaxseeds, fenugreek seeds and their combination had a significant positive effect on plasma luteinizing hormone, follicle‐stimulating hormone, oestradiol‐17β and triglycerides. Inclusion of flaxseeds and/or fenugreek seeds in the diets enhanced the serum glutathione peroxidase and superoxide dismutase activities and reduced the malondialdehyde and total cholesterol concentrations in plasma. Dietary supplementation of flaxseeds and/or fenugreek seeds increased α‐linolenic and linoleic acids in egg yolk. It could be concluded that inclusion of mixed sources of phytoestrogens in diets improved laying performance, egg quality, the antioxidative status, hormonal profile and steroidogenesis in aged laying hens.     

不同饲粮粗蛋白质水平下蝇蛆蛋白替代豆粕对蛋鸡生产性能、蛋清品质及血清蛋白质代谢指标的影响

本试验旨在研究不同饲粮粗蛋白质水平下蝇蛆蛋白替代豆粕对蛋鸡生产性能、蛋清品质及血清蛋白质代谢指标的影响。采用单因素试验设计,选取252只产蛋率、体重相近的健康33周龄罗曼白蛋鸡,随机分为3组,每组7个重复,每个重复12只鸡。各组分别饲喂标准回肠可消化氨基酸(SIDAA)平衡模式下配制的不同粗蛋白质水平(16.50%、14.85%、13.20%)的玉米-豆粕-蝇蛆蛋白饲粮,各组蝇蛆蛋白与豆粕提供等量的粗蛋白质。预试期2周,正试期12周。结果表明:1)与16.50%组相比,14.85%组的产蛋率、平均蛋重、产蛋量、平均日采食量和料蛋比均无显著差异(P>0.05);13.20%组的料蛋比显著增加(P<0.05),产蛋率、产蛋量、平均蛋重和平均日采食量均显著降低(P<0.05)。2)与16.50%组相比,14.85%组的平均蛋重、蛋清重、浓蛋白重、蛋白高度、哈氏单位和蛋清比例均无显著差异(P>0.05);13.20%组的平均蛋重、蛋清重、浓蛋白重和蛋白高度显著降低(P<0.05),而蛋清比例、哈氏单位无显著差异(P>0.05)。3)各组血清谷草转氨酶、谷丙转氨酶活性及总蛋白、白蛋白、尿酸含量无显著差异(P>0.05),且输卵管膨大部组织学形态正常。由此可见,在本试验条件下,使用蝇蛆蛋白替代豆粕并使饲粮粗蛋白质水平降低至14.85%时未对蛋鸡生产性能和蛋清品质产生不良影响,但饲粮粗蛋白质水平降低至13.20%时则会产生不利影响。     

Influence of sumac (Rhus Coriaria L.) and ginger (Zingiber officinale) on egg yolk fatty acid,cholesterol and blood parameters in laying hens

The aim of the study was to evaluate the potential effect of different levels of sumac (Rhus coriaria L.) seed powder and ginger (Zingiber officinale) root powder on egg yolk fatty acid composition, blood/yolk cholesterol in laying hen. A total of 63 (ATAK‐S: Domestic Turkish Laying Hens) laying hens (average weight: 1470 g each hen, 25‐weeks of age) were assigned to seven treatment diets including sumac seed (S) and ginger root powder (G) at 0 g/kg (control), 10 g/kg (S1), 20 g/kg (S2), and 30 g/kg (S3); 10 g/kg (G1), 20 g/kg (G2), or 30 g/kg in rations respectively, for 8 weeks. After a two‐week adaptation period to cages, the hens were allocated to 7 groups with 9 replicates of 1 hen in per cage each. The replications were allotted equally into the upper and lower cages to minimize the effects of cage level. In this study, egg yolk cholesterol had a decrease (p <0.05) in supplemented diet( sumac seed and ginger root powder). Fatty acid content in yolk; saturated fatty acid, monounsaturated fatty acids, polyunsaturated fatty acids and rate of n6/n3 were not significant (p <0.05). However, dietary supplementation with sumac and ginger powder reduced and yolk/blood cholesterol concentrations in laying hens. Supplementation of sumac and ginger affected on HDL, there was found a significant effect (p < 0.05) in treatment groups. Moreover, LDL positively decreased in all treatment groups compared with the control group. The findings of this study suggested that feeding sumac and ginger tend to be decreasing cholesterol levels in both yolk and blood on laying hens. It can be concluded that ginger root and sumac seed powder can be used as an effective feed additive to improve fatty acid composition and yolk and blood cholesterol in ATAK‐S laying hens.     

Effect of different levels of dried citrus pulp on performance,egg quality,and blood parameters of laying hens in early phase of production

Utilization of agricultural wastes in animal nutrition is a matter of great concern. Dried citrus pulp (DCP) is a potential source of some valuable nutrients for animal and poultry. In an experiment with completely randomized design, the effect of different levels (0%, 4%, 8%, 12%, and 16%) of DCP was evaluated on performance, egg quality, and blood parameters of laying hens from 25 to 37 weeks of age. The birds were randomly allocated to five groups with six replicates and three birds in each replicate. The results showed that with increasing the level of DCP up to 12%, there were no significant differences among treatments for feed intake, egg production, egg mass, feed conversion ratio, final body weight, yolk index, and yolk color. There were no significant differences between treatments in shell thickness, eggshell index, egg score, and Haugh unit. Utilization of DCP up to 16% significantly increased serum glucose and high-density lipoprotein and reduced cholesterol, low-density lipoprotein, and triglycerides (P < 0.05). Results of the present study indicated that use of 12% DCP in laying hen diets had no adverse effect on performance and egg quality of laying hens in early phase of production.     

Replacing maize with pearl millet in laying hens’ diets

Pearl millet grain could be considered as an alternative feed ingredient for poultry. In a 12 wks experiment, the performance of laying hens fed diets containing pearl millet were compared with those fed diets containing corn. Maize grain was replaced by pearl millet on an equal-weight at either 0, 25, 50, 75 or 100%. Results showed that use of 25, 50 and 75% of pearl millet in place of maize in the diet resulted in similar (P > 0.05) hen-day egg production, egg mass, egg weight, feed intake and feed conversion ratio to those of control group. Totally replacement of maize grain with pearl millet significantly (P < 0.05) reduced all production parameters. Egg quality parameters did not affect by using pearl millet in the diet. These results showed that maize grain can be replaced by pearl millet up to 75% in the diets of laying hens without any adverse effect on hen performance or egg quality.     

饲粮缬氨酸水平对蛋鸡生产性能、蛋品质及血清生化指标的影响

本文旨在研究饲粮不同缬氨酸水平对蛋鸡生产性能、蛋品质及血清生化指标的影响,并探讨蛋鸡饲粮中缬氨酸的最适添加量.试验选用720只体重相近的40周龄的海兰褐壳蛋鸡,随机分成5组,每组4个重复,每个重复36只鸡,分别饲喂缬氨酸水平为0.6％、0.7％、0.8％、0.9％、1.0％的饲粮,试验期为56 d.结果表明:1)0.8％水平组料蛋比和1.0％水平组平均日采食量分别最低,与其他各组均差异显著(P＜0.05);各组产蛋率、平均蛋重和日产蛋均重均无显著差异(P＞0.05).2)0.8％水平组蛋壳强度最大,1.0％水平组蛋清蛋白质含量最低,与其他各组均差异显著(P＜0.05)或有显著的趋势(P＜0.10);各组蛋壳厚度、哈夫单位、蛋黄颜色、蛋白高度、蛋黄和蛋清相对重均无显著差异(P＞0.05).3)0.8％水平组血清葡萄糖含量最高,显著高于其他各组(P＜0.05);0.8％水平组血清尿素氮和尿酸含量最低,总氨基酸含量最高,与其他各组均有差异显著的趋势(P＜0.10).4)二次曲线分析表明:当饲粮代谢能为11.31 MJ/kg、粗蛋白质水平为15.81％、赖氨酸水平为0.77％时,以料蛋比为评价指标,产蛋高峰期蛋鸡缬氨酸需要量为0.78％,以蛋壳强度和血清白蛋白含量为评价指标,缬氨酸需要量分别为0.81％和0.75％.由此可知,基础饲粮中添加一定量的缬氨酸可降低产蛋高峰期蛋鸡料蛋比,增强蛋壳强度和提高血清葡萄糖含量.     

不同饲粮粗蛋白质水平下黑水虻蛋白替代豆粕对蛋鸡生产性能、蛋清品质及血清蛋白质代谢指标的影响

本试验旨在探讨不同饲粮粗蛋白质水平下黑水虻蛋白替代豆粕对蛋鸡生产性能、蛋清品质及血清蛋白质代谢指标的影响。采用单因素随机试验设计,选用252只产蛋率相近的33周龄罗曼白蛋鸡,随机分为3组,每组7个重复,每重复12只鸡。各组分别饲喂标准回肠可消化氨基酸(SIDAA)平衡模式下配制的不同粗蛋白质水平(16.50%、14.85%、13.20%)的玉米-豆粕-黑水虻蛋白饲粮,各组黑水虻蛋白与豆粕提供等量的粗蛋白质。预试期2周,正试期12周。结果表明:1)与16.50%组相比,14.85组%和13.20%组的产蛋率和平均日采食量无显著影响(P>0.05),平均蛋重显著降低(P<0.05),料蛋比显著升高(P<0.05);13.20%组的产蛋量显著降低(P<0.05),14.85%组的产蛋量无显著差异(P>0.05)。2)与16.50%组相比,14.85%组的平均蛋重、蛋清重、浓蛋白重、蛋白高度、哈氏单位和蛋清比例均无显著差异(P>0.05);13.20%组的平均蛋重、浓蛋白重、蛋白高度显著降低(P<0.05),蛋清重和哈氏单位呈下降趋势(P=0.0513和P=0.0673)。3)各组血清谷草转氨酶、谷丙转氨酶活性及总蛋白、白蛋白、尿酸含量无显著差异(P>0.05)。16.50%和13.20%饲粮粗蛋白质水平对蛋鸡输卵管膨大部分泌功能有轻微不良影响。由此可见,在SIDAA模式下,以黑水虻蛋白替代豆粕并使饲粮粗蛋白质水平降低至14.85%时对鸡蛋蛋清品质无不良影响。     

标准回肠可消化氨基酸模式下降低饲粮粗蛋白质水平对蛋鸡生产性能、蛋品质及氮平衡的影响

本试验旨在研究标准回肠可消化(SID)氨基酸(AA)模式下,降低饲粮粗蛋白质(CP)水平对海兰灰蛋鸡生产性能、蛋品质及氮平衡的影响。选取540只20周龄体重相近且健康的海兰灰蛋鸡,随机分为5个处理,每个处理6个重复,每个重复18只鸡,预试期1周,正试期12周,采食等代谢能(11.82 MJ/kg)、等赖氨酸(Lys,SID Lys为0.831%)、相同AA模式、不同CP水平(18.0%、17.5%、17.0%、16.5%和16.0%)的试验饲粮。结果表明:SID AA模式下,降低饲粮CP水平可极显著降低平均蛋重和CP摄入量(P<0.01),显著降低鸡蛋浓蛋白高度(P<0.05),显著降低蛋鸡摄入氮和排出氮(P<0.05),有提高氮表观利用率的趋势(P=0.05);数据偏相关分析表明,饲粮中SID AA模式外的精氨酸、苯丙氨酸和亮氨酸水平下降与平均蛋重下降显著相关(P<0.05),与浓蛋白高度下降无显著相关(P>0.05)。结果提示,SID AA模式下,降低饲粮CP水平,除影响平均蛋重和浓蛋白高度外,对其他生产性能、蛋品质及血液生化指标影响较小,平均蛋重的下降与低CP饲粮中精氨酸、苯丙氨酸和亮氨酸不足有关;AA平衡的低CP饲粮,可在维持较高生产性能的同时减轻蛋鸡粪氮排出。     

循环高温对蛋鸡生产性能、蛋壳品质及钙磷代谢的影响

本试验旨在模拟夏季蛋鸡舍内的循环高温,研究不同温度对蛋鸡生产性能、蛋壳品质及钙磷代谢的影响。选取28周龄高产海兰褐蛋鸡288只,随机分为21℃适温组(自由采食)、27~30℃循环高温组(自由采食)、29~35℃循环高温组(自由采食)和21℃采食配对组(按前1 d 29~35℃循环高温组的采食量饲喂),每个组6个重复,每个重复12只鸡,分别饲养于4个人工环境控制舱内,试验期4周。结果表明:与21℃适温组相比,27~30℃循环高温组蛋鸡平均日采食量、体增重和平均蛋重显著降低(P0.05),蛋壳强度显著降低(P0.05),蛋鸡钙、磷的代谢率差异不显著(P0.05),但钙、磷的吸收量显著降低(P0.05),除蛋黄颜色显著降低(P0.05)外,鸡蛋品质其他相关指标差异不显著(P0.05);而29~35℃循环高温组除平均日采食量、体增重和平均蛋重显著降低(P0.05)外,产蛋率同样显著降低(P0.05),蛋壳厚度和蛋壳强度均显著降低(P0.05),破蛋率显著升高(P0.05),蛋鸡钙、磷的代谢率差异不显著(P0.05),而钙、磷吸收量同样显著降低(P0.05),鸡蛋蛋白高度和蛋黄颜色均显著降低(P0.05)。与21℃采食配对组相比,29~35℃循环高温组平均蛋重显著降低(P0.05),料蛋比显著提高(P0.05),蛋壳强度显著降低(P0.05),钙、磷的代谢率和吸收量差异不显著(P0.05),鸡蛋品质差异不显著(P0.05)。结果提示,夏季鸡舍内温度在27~30℃波动即可显著降低蛋鸡的体增重、平均蛋重和蛋壳品质;而29~35℃不仅显著降低蛋鸡的体增重、产蛋率、平均蛋重以及蛋壳品质,还显著影响鸡蛋的蛋白高度和蛋黄颜色。高温对蛋鸡产蛋性能及蛋白高度和蛋黄颜色的影响可能与降低采食量有关;高温可能直接影响蛋壳的形成,也可能由于降低钙、磷吸收量影响蛋壳品质。     

Effects of supplemental L-carnitine in drinking water on performance and egg quality of laying hens exposed to a high ambient temperature

The present study was conducted to investigate effects of L-carnitine supplied with drinking water on performance and egg quality of laying hens under high environmental temperature. In the study, 47-week-old laying hens (Brown hisex) were divided into two groups (control and treatment) and fed with a standard layer diet. Treatment group was received 50 p.p.m L-carnitine with drinking water for an 8-week period. Throughout the study, 8 h hot (35-37 degrees C) and 16 h thermoneutral (20-22 degrees C) environmental temperature regime was employed daily. The results showed that L-carnitine supplementation affected some egg quality characteristics of layers under high environmental temperature. Relative albumen weight and height were increased (p < 0.05) by supplemental L-carnitine. Live weight gain, feed intake, egg mass, egg weight, yolk weight, shell weight, yolk index, egg-shape index, yolk colour score and shell thickness were not affected (p < 0.05) by L-carnitine. It is concluded that L-carnitine supplementation in laying hens could have potential to improve albumen quality under high environmental temperature.     

Effects of Microbial Phytase Supplementation on Egg Production and Egg Quality in Hy-line Brown Hens During the Late Laying Period

The objective of this study was to evaluate the effects of microbial phytase on egg production and egg quality in older hens. A total of 216, 63-week-old Hy-line brown laying hens were distributed in a randomized complete design 10-week feeding trial of 3 dietary treatments with 12 replications per treatment and 6 hens per replication. The 3 dietary treatments were corn-soybean meal-based diets supplemented with 0% (CON), 0.06% (TRT1), and 0.12% (TRT2) microbial phytase. Significantly higher hen-day egg production was observed in the TRT1 treatment compared to CON (P<0.05), except during the first two weeks of the experiment. During weeks 3, 4, and 9, TRT2 had a greater hen-day egg production percentage than CON (P<0.05). The damaged egg ratio was not affected. The egg quality parameters (e.g., eggshell color, eggshell strength, albumen height, egg weight, and the Haugh unit) were affected by microbial phytase supplementation (P<0.05). However, there were no significant effects on the eggshell thickness and yolk color. In conclusion, microbial phytase supplementation to the diets of older hens could improve production performance, extend the peak laying period, and alter the egg quality parameters.     

Village chicken production in Turkey: Tokat province example

The aim of this work was to reveal the current form of village chicken production in Tokat province of Turkey. A survey was applied to 153 randomly selected farmers of 5 subdistricts in Tokat province. The ratios of domestic fowls in the survey region were as follows: hen 98.83%, goose 0.65%, turkey 0.29% and duck 0.16% (P < 0.01). Feather colours of laying hens were white (2.76%), brown (8.63%) and mixed color (88.60%). The hen farms in this region consisted of native breeds (91.42%), commercial breeds (5.71%) and their crosses (2.85%). The mean egg weight of the village hens was between 30 and 40 g. Wheat (65.73%) and mixed (wheat, barley, maize and kitchen refuse) feed (34.22%) were used to supplement the hens (P < 0.01). For producing natural chicks, the hens were brooded between 1.10 and 1.46 times/year, 1.31 on average. For each brooding, the number of placed eggs under the broody hens was between 11.39 and 12.42 (P < 0.05).     

Egg production, egg quality and crop content of Rhode Island Red hens grazing on natural tropical vegetation

The aim of this experiment was to study the suitability of the outdoor system for Rhode Island Red hens under the tropical conditions of southern Mexico. Twelve floor pens, each containing four birds, were divided randomly into two groups. The first group was raised indoors only, while each of the second group replicates had access to an outdoor area with natural-grown vegetation from 0800 to 1700 hours daily. Both groups fed ad libitum on a commercial layers diet. The results revealed no differences in body weight between treatments. The outdoor group recorded significantly higher egg laying rate (86.90 vs. 78.05 %), higher egg mass (50.66 vs. 45.30 g egg/hen/day), and higher feed intake (103.70 vs. 97.67 g/day) versus the indoor group. The outdoor group had eggs with darker yellow yolks (9.46 vs. 5.46), lower yolk, and higher albumen proportions (P?<?0.05) versus the indoor group. The crop content of the outdoor hens consisted of 86.55 % concentrated feed, 6.30 % plant material, 2.27 % grit stones, 1.69 % snails and oyster shells, 1.25 % seeds, 0.95 % farm wastes, and 0.99 % insects, worms, and larvae. Of the outdoor hens, 43.1 % was observed to be in the range at each scanning time. The outdoor system in the tropics had beneficial effects on Rhode Island Red hen performance, and the hens utilized the outdoor area effectively and obtained various feed items.     

理想氨基酸模式下低粗蛋白质饲粮对蛋鸡生产性能的影响

本试验旨在研究以理想氨基酸(AA)模式配制的低粗蛋白质(CP)饲粮对21～32周龄蛋鸡生产性能、蛋品质、全血氨浓度和血浆尿酸浓度及粪氮含量的影响.试验选用540只体重相近的健康海兰灰蛋鸡,随机分为5组,每组6个重复,每个重复18只鸡,分别饲喂等能量( 11.00 MJ/kg)的5种CP水平(17.00％、16.50％、16.00％、15.50％和15.00％)的饲粮,试验期12周.结果表明:在理想AA模式下降低饲粮CP水平,蛋鸡产蛋率显著提高(P＜0.05),平均蛋重有降低的趋势(P=0.06),但对平均日采食量、日产蛋重和蛋料比无显著影响(P＞0.05);降低饲粮CP水平极显著影响了蛋白高度和哈氏单位(_P＜0.01),显著影响了蛋黄颜色(P＜0.05),未显著影响蛋壳厚度和蛋壳强度(P＞0.05);饲粮CP水平对各鸡蛋成分均无显著影响(P＞0.05),但鸡蛋蛋白含量随饲粮CP水平的降低有降低的趋势(P=0.09);饲粮CP水平对血浆尿酸浓度及全血氨浓度均无显著影响(P＞0.05);降低饲粮CP水平极显著降低了蛋鸡粪氮含量(P＜0.01).由此可见,在理想AA模式下,适当降低饲粮CP水平可提高蛋鸡产蛋率,改善鸡蛋品质,降低粪氮含量.