The effect of soy isoflavones on egg quality and bone mineralisation during the late laying period of quail

1. Soy isoflavones play a role in calcium and bone metabolism. Poor egg quality, skeletal abnormalities and architectural deterioration of bone tissue are common problems under hot climate conditions and with increased age in poultry. 2. In this study, we investigated the effects of soy isoflavone supplementation on egg production, egg quality, bone mineral density (BMD), levels of osteocalcin (OC), vitamin D, calcium (Ca), phosphorus (P) and alkaline phosphatase (ALP) activity in quail (Coturnix coturnix japonica) during the late laying period. 3. The birds (n = 180; 28 weeks old) were randomly assigned to 6 treatment groups consisting of 6 replicates of 5 birds each in a 2 x 3 factorial arrangement of treatments (temperatures, soy isoflavone concentration). Birds were kept in wire cages in a temperature-controlled room at either 22 degrees C (thermo-neutral, TN) or 34 degrees C (heat stress, HS) for 8 h/d (09:00 to 17:00 h; until the end of the study) and fed either on a basal (control) diet or on the basal diet supplemented with either 400 or 800 mg of soy isoflavones/kg of diet. 4. Heat exposure reduced feed intake, egg production, egg quality, BMD, OC, vitamin D, Ca, P and ALP when the basal diet was given. Feed intake, egg production and egg weight were not affected, while eggshell thickness and eggshell weight increased in soy isoflavone-supplemented quails reared under TN conditions. However, feed intake, egg production, egg weight, eggshell thickness, eggshell weight and Haugh units were positively influenced by soy isoflavone supplementation in HS groups for quail during the late laying period. Bone mineral density, serum OC, vitamin D, Ca, P levels and ALP activity were significantly improved by soy isoflavone supplementation in both the TN and HS groups in quail during the late laying period. 5. Soy isoflavone supplementation of basal diet significantly improved egg quality and bone mineralisation in quail during the late laying period.     

Effects of aflatoxin B1 and fumonisin B1 on body weight, antibody titres and histology of broiler chicks

1. Our objective was to evaluate the toxic effects of aflatoxin B1 (AFB1) and fumonisin B1 (FB1), administered singly or in combination to broilers. 2. Feeds were prepared with concentrations equal to 0, 50 and 200 microg AFB1/kg, and/or 0, 50 and 200 mg FB1/kg, and offered to broiler chicks from 8 to 41 d of age. The experimental design was totally randomised, in a 3 x 3 factorial arrangement with 9 treatments and 12 birds per treatment. Animals were vaccinated against Newcastle disease on d 14 of life and killed at 41 d. 3. Compared with controls, all mycotoxin-treated groups at 41 d had lower body weight and weight gain, and higher relative heart weight. The relative weight of the liver increased only in birds fed diets containing 200 mg FB1, singly or in combination with AFB1. 4. At 35 d, all groups receiving mycotoxin-treated rations had reduced geometrical mean antibody titres, with birds from groups fed combinations of AFB1 and FB1/kg having even lower values, when compared to the other groups. 5. Histological changes were observed only in liver from birds fed mycotoxin-contaminated rations, and in kidneys of birds fed the diet containing 200 microg AFB1 and 200 mg FB1/kg. Main alterations included vacuolar degeneration and cell proliferation of bile ducts in the liver, and hydropic degeneration in renal tubules in the kidneys. 6. We concluded that AFB1 and FB1 in combination have primarily additive effects on body weight, liver structure and immunological response of broilers at the concentrations used.     

饲粮添加不同水平苜蓿粗多糖对蛋鸡生产性能和蛋品质的影响

本试验旨在研究饲粮添加不同水平苜蓿粗多糖对蛋鸡生产性能和蛋品质的影响。选取540只27周龄的海兰褐壳蛋鸡,随机分为6组,每组6个重复,每个重复15只鸡。对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮中添加250、500、1 000、2 000和4 000 mg/kg苜蓿粗多糖的试验饲粮。试验期24周。结果表明:与对照组相比,1)试验1~8周,500、2 000和4 000 mg/kg苜蓿粗多糖添加组产蛋率均显著提高(P0.05);试验9~16周、17~24周和1~24周,250、500、1 000和2 000 mg/kg苜蓿粗多糖添加组产蛋率显著提高(P0.05),料蛋比显著降低(P0.05),且在试验17~24周和1~24周,总产蛋重量显著提高(P0.05),而平均蛋重和采食量无显著差异(P0.05);2)250、500和1 000 mg/kg苜蓿粗多糖添加组在试验第6、8、12、16、20和24周蛋壳颜色显著加深(P0.05),且在试验第8、12、16周较4 000 mg/kg苜蓿粗多糖添加组蛋壳颜色亦显著加深(P0.05);3)2 000 mg/kg苜蓿粗多糖添加组在试验第6、20、24周蛋壳强度显著提高(P0.05);4)试验第8、12、16、20和24周,250、500、1 000和2 000mg/kg苜蓿粗多糖添加组蛋壳厚度显著增加(P0.05),且4 000 mg/kg苜蓿粗多糖添加组在试验第8、20、24周蛋壳厚度亦显著增加(P0.05);5)2 000 mg/kg苜蓿粗多糖添加组在试验第10、12和24周蛋白高度和哈夫单位显著提高(P0.05),且2 000 mg/kg苜蓿粗多糖添加组在试验第10和12周蛋白高度和哈夫单位显著高于250、1 000和4 000 mg/kg苜蓿粗多糖添加组(P0.05)。试验表明,产蛋期蛋鸡饲粮中添加适宜水平的苜蓿粗多糖可以显著提高蛋鸡生产性能,改善蛋品质,且推荐适宜添加水平为250 mg/kg。     

Dietary arginine silicate inositol complex during the late laying period of quail at different environmental temperatures

Arginine silicate inositol complex (ASIdagger; arginine 49.5%, silicon 8.2%, inositol 25%) is a novel material which is a bioavailable source of silicon and arginine. ASI offers potential benefits for vascular and bone health. Poor eggshell quality has been a major economic concern to commercial egg producers. Poor egg quality, skeletal abnormalities and architectural deterioration of bone tissue are common problems under hot conditions and in older birds. The effects of ASI supplementation on egg production, egg quality, levels of osteocalcin (OC) and bone mineral content were investigated in heat-stressed Japanese quail during the later part of the laying period. The birds were randomly assigned to six treatment groups consisting of six replicates of five birds each in a 2 x 3 factorial arrangement of treatments (temperatures, ASI levels). The birds were kept in wire cages in a temperature-controlled room at either 22 degrees C (TN) or 34 degrees C (HS) for 8 h/d and fed either a basal (control) diet or the basal diet supplemented with either 500 or 1000 g of ASI/kg. Heat exposure reduced egg production, egg quality and bone mineralisation when the basal diet was fed. ASI supplementation had no effect on feed intake or egg production under TN or HS conditions. However, ASI supplementation increased egg weight, shell thickness, shell weight and Haugh unit in both TN and HS groups during the late laying period. Bone mineral density (BMD) was significantly improved by ASI supplementation in both TN and HS groups. Serum osteocalcin (OC) concentrations and alkaline phosphatase (ALP) activity increased linearly with dietary ASI supplementation during the late laying period. The amount of calcium and phosphorus in the excreta decreased, while ash, mineral content, calcium and phosphorus concentrations in tibia increased in ASI-supplemented quail in both TN and HS groups during the late laying period. ASI supplementation significantly improved egg quality and bone mineralisation in quail during the late laying period and did not affect feed consumption or egg production.     

绍兴鸭剩余采食量与部分生产性能及蛋品质的相关性分析

本实验旨在探讨绍兴鸭剩余采食量(RFI)与生产性能及蛋品质之间的关系。测定300只绍兴鸭410~470日龄的采食量、体重、平均蛋重、蛋品质,计算出剩余采食量与料蛋比,并分析剩余采食量与生产性能及蛋品质的相关性。结果显示:绍兴鸭平均采食量、平均蛋重、体重、体增重、料蛋比、剩余采食量分别为198.8 g/d、73.0 g、1500.9 g、2.5 g/d、2.7、3.5 g/d;低剩余采食量组的剩余采食量、采食量以及料蛋比极显著低于高剩余采食量组;相关性分析表明,剩余采食量与采食量和料蛋比呈极显著正相关(P<0.01);采食量与平均蛋重、体重呈极显著正相关(P<0.01),与料蛋比呈极显著负相关(P<0.01),与体增重呈显著正相关性(P<0.05);蛋品质分析结果表明,高剩余采食量组仅蛋黄色泽水平显著高于低剩余采食量组;相关性分析表明,剩余采食量与蛋品质各指标间均无显著相关性。本试验结果表明,以剩余采食量为蛋鸭选育指标是可行的,且选育低剩余采食量的鸭子能显著降低采食量,提高饲料效率,且不改变产蛋重及蛋品质。     

Vitamin E supplementation can alleviate negative effects of heat stress on egg production,egg quality,digestibility of nutrients and egg yolk mineral concentrations of Japanese quails

The aim of this study was to determine if the negative effects of high ambient temperature (34 degrees C) on egg production, egg quality, digestibility of nutrients, and mineral content of egg yolk could be alleviated by dietary vitamin E (dl-alpha-tocopheryl acetate) supplementation in laying Japanese quails (Coturnix coturnix japanica). Japanese quails (n=240; 7-week-old) were divided into eight groups, 30 birds per group. The quails were fed either a basal diet or the basal diet supplemented with either 125, 250 or 500 mg of dl-alpha-tocopheryl acetate/kg of diet. Birds were kept at 22 degrees C and 55% relative humidity (RH). At 14 weeks of age, the thermo-neutral (TN) group remained in the same temperature as at the beginning of the experiment, whereas the heat stress (HS) group was kept at an environment-controlled room at 34 degrees C and 44% RH for 3 weeks. Heat exposure decreased performance when basal diet was fed (P=0.001). With 250 and 500 mg/kg of diet, an increase in body weight (P=0.01), feed intake (P=0.01), egg production (P=0.001), and improvement in feed efficiency (P=0.01) was found with vitamin E supplementation in quails reared under heat stress conditions (HS). Similarly, egg weight (P=0.01), egg specific gravity (P=0.01), egg shell thickness (P=0.05) and Haugh unit (P=0.01) were positively influenced by vitamin E supplementation. Heat exposure decreased digestibility of dry matter (DM) (P=0.03), organic matter (OM) (P=0.05), crude protein (CP) (P=0.02), ether extract (EE) (P=0.05) and were elevated by supplemental vitamin E (P相似文献   

Juniper oil improves oxidative stability and eggshell and albumin quality of quail eggs

1. The aim of this study was to determine the effects of juniper oil (JO) dietary supplementation on the laying performance, egg traits and egg malondialdehyde (MDA) concentrations of quail.

2. A total of 400 female Pharaoh quails were equally divided into 4 groups containing 100 quails (5 replicates of 20 quails each). The study included a control treatment with no diet additives, and the treatments were as follows: (group 1) 100 mg JO/kg; (group 2) 200 mg JO/kg; (group 3) 300 mg JO/kg. The experiment was carried out for 60 d.

3. At the end of the experiment, there were no significant differences in body weight, egg weight, egg mass, egg shape index, yolk colour, egg production, feed consumption or feed efficiency.

4. The Haugh unit was increased in groups 2 and 3 compared to the control group. Dietary fortification with JO improved eggshell thickness and breaking strength compared to the control group. Furthermore, the damaged egg ratio was significantly decreased in group 3 compared to the control. The increasing concentration of JO (200 and 300 mg/kg) caused a significant decrease in egg yolk MDA concentration after 15 and 30 d of storage at 20°C.

5. It was concluded that inclusion of JO in layer diets can improve egg quality characteristics in terms of Haugh unit, eggshell thickness and breaking strength. Moreover, supplementation of JO in the diets of quail may enhance the antioxidant status of eggs, and the most effective doses of JO were 200 and 300 mg/kg.     

苜蓿多糖对夏季高温环境下蛋鸡生产性能及蛋品质的影响

本试验旨在研究夏季高温环境下在饲粮中添加苜蓿多糖对蛋鸡生产性能及蛋品质的影响。将540只156日龄海兰褐蛋鸡随机分成6组,每组6个重复,每个重复15只鸡。对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮中添加250、500、1 000、2 000和4 000 mg/kg苜蓿多糖的试验饲粮。试验期为6周。结果显示:与对照组相比,1)饲粮中添加不同水平苜蓿多糖对平均蛋重、平均日采食量、不合格蛋率和死淘率均无显著影响(P0.05),而添加500、1 000和4 000 mg/kg苜蓿多糖显著提高了蛋鸡的产蛋率(P0.05),添加500、1 000、2 000和4 000 mg/kg苜蓿多糖显著降低了料蛋比(P0.05)。2)饲粮中添加不同水平苜蓿多糖对蛋白高度和哈夫单位均无显著影响(P0.05);250 mg/kg苜蓿多糖添加组第4和6周末的蛋黄颜色显著提高(P0.05);500 mg/kg苜蓿多糖添加组第6周末的蛋形指数显著降低(P0.05),第1、4和6周末的蛋黄颜色显著提高(P0.05);1 000 mg/kg苜蓿多糖添加组第4和6周末的蛋壳颜色显著加深(P0.05),第1、2和4周末的蛋壳强度和蛋壳厚度显著提高(P0.05),第1和6周末的蛋形指数显著降低(P0.05),第1、2、4和6周末的蛋黄颜色显著提高(P0.05);2 000 mg/kg苜蓿多糖添加组第1和4周末的蛋壳厚度显著提高(P0.05),第6周末的蛋形指数显著降低(P0.05),第1、4和6周末的蛋黄颜色显著提高(P0.05);4 000 mg/kg苜蓿多糖添加组第4周末的蛋壳颜色显著加深(P0.05)且蛋壳强度显著提高(P0.05),第1和4周末的蛋壳厚度显著提高(P0.05),第6周末的蛋形指数显著降低(P0.05),第1、4和6周末的蛋黄颜色显著提高(P0.05)。结果表明,夏季高温环境下,在饲粮中添加适量的苜蓿多糖可以有效缓解蛋鸡的热应激,提高蛋鸡的生产性能,改善蛋品质,且适宜添加量为1 000 mg/kg。     

Effects of supplementary iodine on the performance and egg traits of laying hens

1. This experiment was carried out to determine the effects of dietary iodine supplementation on the performance and egg traits of laying hens. A total of 600 SHSY type brown layers aged 21 weeks of age were chosen at random from a large flock. They were randomly distributed into 30 pens at 20 hens per pen. Each treatment comprised 6 replicates of 20 layers in groups of 5 birds. The diets were supplemented with 0, 3, 6, 12 and 24 mg/kg iodine as calcium iodate. The experimental period lasted 30 weeks. 2. There were no significant differences among the groups in body weight, food consumption, egg production, food consumption per kg eggs, eggshell index, eggshell breaking strength, shell thickness or egg yolk index. 3. Supplementation of the diet with 12 mg/kg iodine increased food consumption per dozen eggs compared to the groups fed on diets supplemented with 0 and 6 mg/kg iodine. 4. Egg weight was less in groups fed on diets supplemented with 12 and 24 mg/kg iodine than in the group receiving no iodine supplementation. 5. Iodine supplementation to provide 12 and 24 mg/kg reduced egg albumen index and egg Haugh units. 6. There were no significant differences among the groups in egg cholesterol and egg yolk cholesterol contents. 7. The iodine concentrations in egg yolk, egg albumen and whole egg increased with increased iodine supplementation. 8. As a result, the 3 and 6 mg/kg iodine supplementation of diet could be used to enrich the eggs with iodine without any adverse effect on performance and egg traits.     

Effects on health and blood plasma parameters of laying hens by pure nivalenol in the diet

The effects of trichothecene nivalenol (NIV) on the health and production of laying hens were determined in a feeding study. White Leghorn hens, 55 weeks old, were fed diets containing 0, 1, 3 and 5 mg NIV/kg during 50 days. Feed intake was reduced by NIV, but there were no effects on body weight, egg production and egg quality. Traces of unaltered NIV were found in liver and bile. Alkaline phosphatase in the blood plasma increased in the hens fed 0, 1 and 3 mg NIV/kg diet but decreased in the birds fed 5 mg NIV/kg feed. Total protein and glucose were slightly reduced in hens fed 5 mg NIV/kg diet. Pathological examination revealed that 40-75% of hens fed NIV (3 and 5 mg/kg) supplemented diet showed gizzard lesions, haemorrhages in the duodenum and swollen cloaca and oviducts with immature eggs while certain birds in the 1 mg NIV group showed light and fragile livers. NIV and the metabolite de-epoxy-NIV in faeces were found to constitute up to 10% of ingested NIV.     

Effects of thymol and isoeugenol feed supplementation on quail adult performance,egg characteristics and hatching success

1. A study was conducted to evaluate whether feed supplementation with thymol or isoeugenol can alter Japanese quail growth rate and final body weight, the female onset of puberty, hen-day egg production and the physical and chemical characteristics of the egg, as well as its potential to alter hatchability.

2. From 4 to 16 weeks of age, birds from each cage (1 male: 3 females) were assigned to 1 of 3 treatments that differed in the supplement added to the feed: control, thymol or isoeugenol (400?mg/kg). The average ages (d) at first egg lay (FIRST), at 25% egg production (A25% EP), at 50% egg production (A50% EP) and weekly and cumulative hen-day egg production (HDEP) were calculated. In addition, physical and chemical characteristics of the eggs, their fertility and hatchability were also evaluated for each group.

3. Feed supplementation did not significantly affect growth rate, final body weight, egg production parameters, fertility and physical characteristics of egg or most of the fatty acid components of the yolk.

4. The group treated with isoeugenol showed an increase in the percentage of palmitoleic fatty acid compared to the control, with thymol group showing intermediates values.

5. Both thymol and isoeugenol supplemented groups showed increased hatchabilities, by 18·8% and 11·8%, respectively, compared to their control counterparts.

6. The improvement in the hatching success of the eggs from the thymol and isoeugenol supplemented groups without a negative impact on their performance may have important economic implications for future breeding programmes, particularly if these effects generalise from quail to other more commercially important poultry species, such as chickens or turkeys.     

Use of L-carnitine and humate in laying quail diets

This experiment was carried out to determine the effects of using L-carnitine and humate alone or in combination in quail diets on laying performance, egg traits and blood parameters. A total of 280 Japanese quails aged 10 weeks, divided into one control group and three treatment groups, were used. The diets of the first, second and third treatment groups were supplemented with 100 mg L-carnitine/kg, 1.5 g humate (Farmagülat?r Dry Plus)/kg and 100 mg L-camitine + 1.5 g humate/kg, respectively. The experimental period lasted 16 weeks. The addition of L-carnitine and sodium humate alone or in combination did not significantly affect body weight, feed consumption, egg production, feed conversion ratio, mortality, egg-shell thickness, egg yolk index and the percentages of egg-shell, albumen and yolk. Egg weight increased (P < 0.001) with L-carnitine supplementation. The values of egg albumen height (P < 0.05), egg albumen index (P < 0.01) and egg Haugh unit (P < 0.05) were increased with humate supplementation. Egg cholesterol content and blood serum parameters were not affected by the supplementation of L-carnitine with or without humate. The results in this study demonstrated that L-carnitine supplementation increased egg weight while humate addition increased egg albumen index and egg Haugh unit of laying quails. However, the combined administration of L-carnitine and humate did not have any significant effects on the parameters measured.     

Effects of supplemental vitamin E during the laying period on the reproductive performance of Taiwan native chickens

1. One-day-old Taiwan Native Breeder female chicks were fed on maize/soybean growing diets without supplemental vitamin E from hatch to 17 weeks of age. After 17 weeks the birds (n = 300) were randomly assigned to 5 dietary treatments and fed on maize/soybean laying diets supplemented with 0, 40, 80, 120 and 160 mg/kg of vitamin E (dl-alpha-tocopherol acetate), respectively, until 46 weeks of age. The variates measured included: age at first egg, feed consumption (FC), feed efficiency (FE), egg production (EP), egg weight (EW), egg specific gravity (ESG), eggshell strength (ESS), fertility and hatchability. 2. The addition of 120mg/kg of vitamin E lowered the first EW (P<0.05); however, there was no significant difference in the age or body weight (BW) of pullets at first egg or mortality rate to 46 weeks of age among the treatments. FE and egg mass were improved (P<0.05) in pullets fed 80 mg/kg of supplemental vitamin E. A significant increase in EP was observed after peak EP in pullets given 80 mg/kg of supplemental vitamin E. However, this favourable effect decreased as supplemental vitamin E exceeded 80 mg/kg. 3. From 17 to 46 weeks of age, egg quality (ESG and ESS) decreased with age. However, there was no correlation between age and fertility or hatchability during the experimental period, suggesting that egg quality is more age-sensitive than reproductive performance for breeder pullets. 4. Compared with the control, fertility and hatchability of all eggs set for the treatment with 80 mg/kg supplemental vitamin E increased by 7.7 and 13.4%, respectively. There was no difference in the hatchability of fertile eggs. 5. These results suggest that using supplemental vitamin E during the laying period can improve the reproductive performance of breeder pullets. The addition of 80 mg/kg of vitamin E obtained the best performance in EP, egg mass, FE (feed/egg), hatchability and fertility.     

Effects of poppy seed meal on egg production and hatching results in quail (Coturnix coturnix japonica)

This study was carried out to determine the effects of poppy seed meal (PSM) on the egg production and hatching of quail. Two experiments were undertaken. In the first experiment, 240 quail, reared under the same conditions, were divided into four groups of 60 birds each (which were, in turn, subdivided into four subgroups of 15 each for experimental replicates). The first, second, and third experimental groups were fed ratios containing 5%, 15%, and 25% PSM, respectively, over 12 weeks. The control group received no PSM. Feed and water were supplied ad libitum and artificial light was provided for 16 h a day. During the first experiment, egg production, egg weight, and feed conversion ratio (FCR) were measured. In the second experiment, 240 female and 48 male quail were divided into four groups, as in the preceding experiment, and the birds were housed in cages at a ratio of one male to five females. The diets and their presentation to the quails were the same as in the preceding experiment. The results of the two experiments showed that the addition of PSM to the feed ratios increased egg production, feed consumption, and feed conversion per kg of eggs and per dozen eggs. However, PSM addition at all percentages significantly reduced (P<0.001) hatchability, mainly because of increased infertility and embryonic deaths.     

The long-term effects of using a higher amount of iodine supplement on the efficiency of laying hens

1. Two different levels of dietary iodine supplement (K + 0, 3.57 mg/kg; K + I, 6.07 mg/kg) were used in a 52-week experiment using 32 ISA Brown laying hens. 2. The greater iodine content in the diet impaired the egg production (K + 0, 319.9 +/- 1.31 eggs/hen; K + I, 312.4 +/- 4.19 eggs/hen), the egg weight (K + 0, 64.4 + 0.66 g; K + I, 63.1 +/- 0.61 g) and the food to egg mass ratio (K + 0, 2.13 +/- 0.023 kg/kg; K + I, 2.22 +/- 0.030 kg/kg). 3. The greater dietary iodine content had significant (P<0.05) negative effects on Haugh units, yolk index and eggshell weight.     

酶菌混合制剂对产蛋中后期海兰褐蛋鸡产蛋性能与粪便酸溶蛋白含量的影响

为探究酶菌混合制剂对蛋鸡生产性能及蛋品质的影响,以52周龄海兰褐蛋鸡为研究对象设置试验组和对照组,试验组根据酶菌混合制剂添加量的不同分为高、中、低三组,依次添加750 g/t、500 g/t、250 g/t的酶菌混合制剂,对照组饲喂基础饲粮。检测各组蛋鸡粪便酸溶蛋白、产蛋数、蛋重、哈氏单位、蛋壳强度、破软蛋率及耗料量等指标。结果显示:(1)试验组蛋鸡自饲喂第3天开始粪便酸溶蛋白含量显著低于对照组(P<0.05),低剂量组自饲喂第5天起粪便酸溶蛋白含量显著低于对照组(P<0.05)。(2)试验组产蛋率、蛋重、料蛋比与对照组差异显著(P<0.05)。(3)试验组哈氏单位、蛋壳强度、破软蛋率与对照组差异显著(P<0.05)。结果表明,酶与益生菌联合应用可有效降低蛋鸡粪便酸溶蛋白含量,提高蛋鸡生产性能,并能改善蛋品质。     

乳酸锌对蛋鸡生产性能及蛋壳质量的影响

本试验旨在研究乳酸锌对蛋鸡生产性能及蛋壳质量的影响。试验采用单因子随机分组试验设计,选取1600只360日龄的罗曼粉壳蛋鸡,随机分到4个处理组,各处理组8个重复,每个重复50只鸡。基础饲粮采用为玉米－豆粕型粉状饲粮,处理1饲喂基础饲粮＋60mg／kg－水硫酸锌（以锌计）,处理2饲喂基础饲粮＋60mg／kg乳酸锌（以锌计）,处理3饲喂基础饲粮＋40mg／kg乳酸锌（以锌计）,处理4饲喂基础饲粮＋60mg／kg锌（－水硫酸锌和乳酸锌提供的锌各一半）。试验结果表明,在产蛋鸡饲粮中100％以乳酸锌替代硫酸锌（提供的锌含量为60mg／kg）,能显著降低平均破蛋率,提高平均蛋壳强度和平均蛋壳厚度（P〈0．05）,死亡率最低,对蛋鸡的平均产蛋率、平均蛋重、平均日采食量和平均料蛋比无显著影响（P〉0．05）。     

不同锰源与水平对蛋鸡产蛋后期生产性能和蛋品质的影响

试验旨在研究添加不同锰源与水平羟基蛋氨酸锰对蛋鸡产蛋后期生产性能和蛋品质的影响。对照组饲喂加含106 mg/kg硫酸锰(以锰计)的基础日粮,其余各组分别添加30、50、70 mg/kg的羟基蛋氨酸锰(以锰计)来替代基础日粮中的硫酸锰。结果表明:与对照组相比,试验第14 d,日粮中添加30 mg/kg羟基蛋氨酸锰显著提高了蛋壳厚度(P<0.05),添加50 mg/kg羟基蛋氨酸锰显著提高了蛋壳重(P<0.05);试验第28 d,日粮中添加50 mg/kg羟基蛋氨酸锰显著提高了蛋壳厚度(P<0.05),添加30 mg/kg羟基蛋氨酸锰显著改善蛋壳颜色(P<0.05);试验第42 d,蛋壳厚度与添加量呈二次曲线关系,蛋壳厚度在添加量为50 mg/kg时达到最大值(P<0.01)。与对照组相比,试验第14 d,日粮中添加30 mg/kg羟基蛋氨酸锰显著降低了鸡蛋的哈夫单位和蛋黄比例(P<0.05)。试验第42 d,与对照组相比,日粮中添加30 mg/kg羟基蛋氨酸锰显著降低了鸡蛋的蛋黄比例(P<0.05)。试验结果表明,添加50 mg/kg的羟基蛋氨酸锰来替代基础日粮中的硫酸锰效果最好。     

Effect of dietary digestible lysine concentration on performance,egg quality,and blood metabolites in laying hens

An experiment was conducted to evaluate the effect of dietary digestible lysine concentration on productive performance, egg quality, and blood metabolites in laying hens. A completely randomized block design was performed with 5 treatments and 6 replicates of 8 Hy-line W-36 hens each, from 32 to 44 wk of age. The treatments were 5 digestible lysine concentrations (0.657, 0.707, 0.757, 0.807, and 0.857% of diet). Feed intake was significantly increased with each increment in dietary digestible lysine concentration. Significant improvement in egg production, egg weight, egg mass, Haugh unit, and FCR were observed by an increase in lysine intake. Dietary lysine concentration did not have a significant impact on percentage of egg components, specific gravity, eggshell thickness, DM, and protein constituents of eggs. Dietary digestible lysine concentration did not have a significant effect on triglyceride, cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), uric acid, and total protein in plasma. The digestible lysine requirements for optimal egg production, egg mass, and egg weight (32 to 44 wk of age), based on the linear broken-line regression analysis, were 814, 810 and 778 (mg/b/d), respectively. Whereas, these values were 4, 3.9, and 6 percent less than those estimated by the quadratic broken-line model, respectively.     

Evaluating the nutritional value of date pits and demonstrating their application in laying hen diets

This experiment was carried out to study the feeding value of ground date pits (DP) (Phoenix dactylifera L.) with and without enzyme supplementation on laying hens’ performance. Apparent metabolizable energy value of DP was determined by the total collection method using 10 adult Leghorn cockerels. After that, a total number of 144 Lohmann 50‐week‐old LSL‐Lite hens were randomly allocated into six groups consisting of four replicates of six birds, based on a 3 × 2 factorial arrangement of the treatments. Six iso‐caloric and iso‐nitrogenous experimental diets including I‐corn–soya bean meal‐based control, II‐corn–soya bean meal oil‐based control and III‐ corn–soya bean meal‐based diet (180 g/kg DP) were formulated. Each of the diets was supplemented with two levels of an enzyme (0.0 and 0.07 g/kg Natozim Plus). The experiment lasted 10 weeks after 7 days of adaptation. The results revealed that there was no significant difference in feed intake, feed conversion ratio, egg production, egg mass, eggshell weight, eggshell thickness and Haugh unit among the treatments. Dietary inclusion of DP significantly decreased body weight gain (BWG), egg weight and yolk colour score. On the other hand, corn–soya bean meal‐based control diet with vegetable oil significantly increased egg weight and BWG of birds in comparison with other treatments. The serum biochemical metabolites were not affected by DP and enzyme supplementation. Thus, DP can be used as alternative feedstuff in laying hen diets, up to 18% of the diet with little effect on the performance of hens, including egg weight, and also, it had an adverse effect on yolk colour. Eventually, in terms of performance, the results failed to demonstrate any positive effect of Natozim Plus on either the controls or 18% DP diets.