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1.
1. One hundred and twenty 16-week-old, single combed pullets of three strains were fed on a diet containing 160 g protein/kg with or without 50 g clinoptilolite/kg in a trial with 20 hens per treatment. Sterile river sand replaced clinoptilolite in the control diet in order to keep the diets isonergetic. 2. The hens were individually caged in a naturally-ventilated laying house and fed on one of the two diets for ten 28-d periods. 3. No significant dietary effects between treatments were observed with respect to body weight, age at first egg, egg weight, Haugh scores or food intake/hen. 4. Significant dietary effects in favour of clinoptilolite feeding were noticed with the number of eggs laid per hen, shell thickness, efficiency of food utilisation, droppings moisture content and mortality. 5. Significant differences between strains were observed with respect to all measurements taken except food intake/hen d.  相似文献   

2.
试验用38周龄健康的罗曼粉壳蛋鸡600只,经饲喂玉米-豆粕-麦麸型基础日粮(蛋氨酸0.22%、蛋氨酸+胱氨酸0.48%)10d后,随机分为4个处理,每个处理5个重复,每个重复30只蛋鸡。处理1为对照组,饲喂基础日粮;处理2在每千克基础日粮中添加1.325gDL-Met;处理3和处理4以液体蛋氨酸羟基类似物(HMB,活性物质88%)在等摩尔基础上按100%或50%分别替代处理2的DL-Met。试验期10周。试验结果表明:在基础饲粮中添加DL-Met以满足高产蛋鸡的蛋氨酸需要可提高3～10周的产蛋率,并极显著地提高了3～10周的蛋重、日产蛋重、干物质、钙、磷和粗蛋白的表观代谢率(P<0.01),极显著降低了饲料转化率比(P<0.01),对采食量、鸡蛋蛋形指数、破蛋率、软蛋率、蛋黄重、蛋黄比例、哈氏单位、蛋壳重、蛋壳厚度、蛋壳强度、鸡蛋水分和粗蛋白含量无显著影响(P>0.05)。在等摩尔基础上HMB以100%或50%替代DL-Met,对蛋鸡生产性能、鸡蛋品质和养分代谢率的影响与DL-Met无显著差异。结果表明在蛋鸡玉米-豆粕-麦麸型饲粮中HMB的生物学效价与DL-Met相同。  相似文献   

3.
1. The effects of feeding a screw-press expelled cottonseed meal (CSM) to laying hens at dietary concentrations of up to 300 g/kg, were studied over a 10 week period. 2. The overall performance of hens fed on a 75g CSM/kg diet was not significantly different from controls but a 300g CSM/kg diet, containing 255 mg free gossypol/kg and 87 mg cyclopropenoid fatty acids (CPFA)/kg and giving daily intakes per hen of 26.2 mg free gossypol and 9.0 mg CPFA, significantly reduced food intake (P less than 0.01) and egg production (P less than 0.01). The 150g CSM/kg diet (daily intakes of 14.6 mg free gossypol and 4.8 mg CPFA per hen) did not produce adverse effects initially but egg production was slightly depressed towards the end of the experimental period. 3. Treatment of the CSM with a solution of ferrous sulphate hepta-hydrate for inclusion in a 300g CSM/kg diet (100 mg/kg supplemental dietary iron) further reduced food intake (P less than 0.05) and egg production (P less than 0.05). 4. Storage of eggs at warm temperatures for up to 1 month did not lead to discolourations of any kind in the CSM diet groups, but resulted in yolk mottling, a condition reduced by treatment of the CSM with iron. 5. Storage of eggs at cold temperatures for 3 months resulted in brown yolk discolouration and the initial stages of pink albumen discolouration in the 300g CSM/kg diet group; the brown yolk discolouration was reduced by treatment of the CSM with iron.  相似文献   

4.
1. One hundred and twenty 16‐week‐old single combed pullets of three strains were fed on a diet containing 135 g protein/kg with or without 50 g clinoptilolite/kg in a trial with 20 hens per treatment. Sterile river sand replaced clinoptilolite in the control diet in order to keep the diets isoenergetic. The hens were individually caged in a naturally ventilated laying house and fed one of the two diets for ten 28‐d periods.

2. Significant dietary effects of feeding clinoptilolite were observed with number of eggs laid per hen, shell thickness, efficiency of food utilisation and droppings moisture content. No significant dietary effects between treatments were observed with body weight, age at first egg, egg weight, Haugh units, food intake/hen and rate of amino acid absorption of radioactive lysine and methionine into the bloodstream. Significant differences between strains were observed with regard to all parameters except food intake/hen. There were no significant strain × clinoptilolite interactions.  相似文献   


5.
1. A 5 3 factorial experiment was carried out with caged White Leghorn hens with 5 concentrations of calcium (26.0, 29.0, 32.5, 36.0, 39.0 g/kg) and 3 concentrations of phosphorus (4.3, 5.0 and 6.0 g/kg) for 120 d. Variables observed were hen day egg production, food consumption, shell weight, shell weight per unit surface area (SWUSA) and egg content. 2. 36.0 g calcium (Ca) and 4.3 g phosphorus (P) kg were found to be the dietary concentrations that resulted in optimal hen day egg production, shell weight, SWUSA and egg content. 3. Lack of a significant interaction between the effects of calcium and phosphorus on production parameters showed that the dietary Ca: P ratio is not of great importance for the laying hen. 4. Absolute retentions of Ca and P were inversely related to percentage retentions. 5. A balance study of calcium and phosphorus also showed optima at 36.0 g Ca and 4.3 g P per kg. 6. It was inferred that 36.0 g Ca and 5.0 g total P per kg are the optimal concentrations in diets for caged layers in a tropical climate.  相似文献   

6.
Forty-five-week-old commercial leghorns negative for antibodies to Mycoplasma gallisepticum (MG) and M. synoviae were vaccinated with high-passage F strain MG (FMG). Hens were confined in modified Horsfall-Bauer isolation units through 60 weeks of age. Egg production (% hen day) and parameters of egg and eggshell quality were monitored, including egg weight, eggshell strength, Haugh unit score, pimpling, and blood/meat spot incidence. Egg production was significantly lower (P less than 0.05) for FMG vaccinates than controls (down 5.76% and 5.80% in Trials 1 and 2, respectively). However, vaccinates and controls did not differ significantly in eggshell strength, shell thickness, pimpling, or blood/meat spot incidence. Haugh unit scores were significantly (P less than 0.05) greater for FMG vaccinates. At necropsy, all reproductive tracts appeared grossly normal. These studies suggest that high-passage FMG vaccination of post-production-peak hens does not adversely affect oviduct function.  相似文献   

7.
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.  相似文献   

8.
1. Laying hen performance, egg quality, intestinal viscosity and nutrient apparent digestibility were evaluated with respect to the main cereal used in the diet and dosage rate of a fungal beta-glucanase/xylanase enzyme complex. 2. Twelve diets were arranged factorially, with three soluble fibre cereals (SFC); 500 g/kg of wheat or barley or 350 g/kg of rye, and 4 enzyme concentrations (0, 250, 1250 and 2500 mg/kg). An additional control diet based on maize was also included. 3. The use of SFC in the diet instead of maize did not affect egg production or food efficiency, but hens fed on SFC diets exhibited a higher incidence of dirty eggs than hens fed on the maize diet (8-6 vs 4.6%; P<0.01). 4. Laying hens fed on enzyme-supplemented diets produced more eggs (2.1%; P<0.05) and had better food efficiency per dozen eggs (2.5%; P<005) than hens fed on non-supplemented diets. An excess of enzymes in the diet (10 times the recommended dose) did not produce any deleterious effect on laying hen productivity. 5. Enzyme supplementation (ES) reduced intestinal viscosity (P<0.001) and the incidence of dirty eggs (P<0.01). The reduction in viscosity was more pronounced in barley than in wheat or rye diets (P<0.05). 6. Apparent nutrient digestibility in SFC diets was higher with ES, including dry matter (3.1%; P=0.08), fat (4.4%; P<0.001), non-starch polysaccharides (83.3%; P<0.01) and AMEn (2.5%, P<0.01). 7. It is concluded that substitution of maize by SFC is facilitated by ES, especially with respect to egg production, food conversion efficiency and egg shell cleanliness. An excess of enzymes did not produce any deleterious effect on nutrient digestibility or performance of laying hens.  相似文献   

9.
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   

10.
1. This study was conducted as three trials. 2. In the first trial, zinc, manganese, copper and iron concentrations were determined in dietary raw materials collected from various regions of Turkey. 3. In the second trial, 200 Hisex Brown laying hens, 30 weeks of age, were divided into two groups. The first group served as controls and were fed on a standard commercial layer diet. The second group were fed on a commercial layer diet that was not supplemented with trace minerals and vitamins. Egg production, egg weight, specific gravity, food consumption and food efficiency of the birds in each group were determined. In the unsupplemented group, egg production (0.75 vs 0.83) and food intake (114 vs 122 g) were lower than the those of the control group (P < 0.05). Food efficiency was 2.42 (kg food/kg gain) in the group consuming the unsupplemented diet and 2.36 in the controls. 4. In the third trial, as in Trial 2, Hisex Brown laying hens, 62 weeks of age were used. In the unsupplemented group, the mean egg weight was significantly lower than that of controls (68.0 vs 69.6 g) (P < 0.01). 5. At the end of the second and third trials, egg samples collected from experimental groups were hard boiled in water. The levels of zinc, manganese, copper and iron in the egg yolk were determined. The zinc level of the egg yolk from the control group of second trial was higher (23.5 mg/kg) than those of the unsupplemented group (13.6 mg/kg).  相似文献   

11.
1. Three experiments were carried out with light strain laying hens to evaluate the effects of relatively high doses of dietary vitamin E (125 mg/kg food) or ethoxyquin (EQ) (250 mg/kg food) on their laying performance. The control diet contained 5 and 125 mg/kg vitamin E and EQ, respectively. The experimental diets were fed either from one or 32 weeks until 88 or 89 weeks of age. 2. The two antioxidants did not affect the growth of the pullets, age at first egg, final body weight, average egg weight or relative abdominal fat pad size and liver weight at the termination of the experiments. In two out of three experiments, vitamin E and EQ did not affect egg production, food efficiency or mortality; in the third experiment vitamin E significantly (P less than 0.05) improved egg production and food efficiency after an outbreak of Newcastle disease which occurred at 34 weeks of age. EQ significantly reduced mortality during the course of this experiment, but did affect the variables of performance. In two experiments vitamin E consistently improved shell density, although a significant effect was observed in only one of the eight determinations carried out. EQ did not affect this variable. 3. The uterine muscle was more susceptible to oxidation than the drumstick meat, as evaluated by TBA values. In both tissues, vitamin E significantly and consistently decreased TBA values and restricted their increase during incubation, while EQ was less effective, particularly in the drumstick meat. 4. It is concluded that increasing vitamin E and EQ concentrations in diets of laying hens have no effect on the decrease in egg production due to aging. However, vitamin E may minimize the decline in egg production and food efficiency following the outbreaks of some diseases and slightly improve--under certain yet undefined conditions--shell density.  相似文献   

12.
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.  相似文献   

13.
Three diets, containing nearly 12.5 MJ/kg (3.0 kcal ME/g) and 14.6, 11.3 and 9.1 % crude protein, were fed to 1680 light‐hybrids from 12 to 18 weeks of age. Body weight at 18 weeks was depressed by 5 and 9% and age at sexual maturity delayed by 2.4 d and 2.8 d for groups fed the intermediate and lowest protein diets respectively. Mortality during the experiment was slightly higher in the group receiving the higher protein diet. There were no consistent or significant treatment differences in mortality during the laying period. Both hen‐day rate of lay and egg weight decreased slightly and insignificantly but progressively with decreasing protein level of diets fed in the 12‐ to 18‐week period. Savings in food costs in the 12‐ to 18‐week period from feeding the cheaper lower‐protein diets were more than offset by the reductions in egg output and returns which resulted.  相似文献   

14.
1. An experiment was conducted with 144 caged hens to study the effects of different dietary concentrations of phosphorus and of food restriction on the reproductive performance of dwarf breeder hens and on the growth and the bone development of their progeny. 2. Severe food restrictions at 105 g/hen day compared to 115 g/hen day, decreased hen body weight and hen day egg production. Fertility was unaffected and hatchability slightly depressed by the more severe restriction. 3. Egg and one-day-old chick weights were decreased by limiting the food intake of the breeders but the negative effect disappeared at slaughter (7 weeks). 4. Shell quality decreased as the dietary phosphorus increased and was not affected by food allowance. Albumen quality was slightly impaired in severely restricted hens. 5. Serum inorganic phosphorus in hens and yolk phosphorus increased with increasing dietary phosphorus. Tibial breaking strength and tibial percentage ash of the progeny at hatching was markedly improved in proportion to maternal phosphorus and food intake. This improvement in bone quality was not maintained at 7 weeks. 6. The number of chicks affected by twisted legs (valgus) and dyschondroplasia were similar whatever the maternal diet. The frequency of valgus was higher in males than in females. 7. It is concluded that maternal food intake and phosphorus supply are of importance for the initial bone development of the progeny.  相似文献   

15.
1. An experiment was conducted to determine the effects of self-selection of dietary protein and energy by turkey hens on reproductive performance in a warm environment. 2. Dietary self-selection had no significant effect on egg production, egg weight, or body weight of turkey hens. 3. Fertility and hatchability of eggs produced by self-selecting hens were significantly reduced compared to eggs from control hens fed on a complete diet. 4. Protein intake was significantly reduced among self-selecting hens when compared to control hens fed on a complete diet (P less than or equal to 0.001). 5. Food and energy intake decreased as the ambient temperature increased. Nevertheless, protein intake of self-selecting hens increased over the course of egg production despite decreasing food intake. Therefore, self-selecting hens preferred a diet with a greater protein content (g protein/kg diet) in the last 10 weeks of egg production than during the first 10 weeks of egg production.  相似文献   

16.
珍珠鸡是从国外引进,经人工驯养育成的一个特色品种,其蛋用性能获得了显著进展,为加快蛋产品的开发力度,增加其附加价值,对珍珠鸡蛋和海兰褐鸡蛋蛋品质及营养成分进行比较分析。试验随机抽取新鲜珍珠鸡蛋、海兰褐鸡蛋各100枚,测定其蛋外、内在品质及主要营养成分,采用Duncan新复极差法、皮尔逊相关系数进行比较分析。研究表明,在外部品质方面,海兰褐鸡蛋蛋重高于珍珠鸡蛋15.54g（35.61%）,有极显著差异（P〈0.01）;珍珠鸡蛋蛋壳厚度比海兰褐鸡蛋的蛋壳厚0.14mm（40%）,差异极显著（P〈0.01）;由于蛋重的差异,两种鸡蛋蛋黄比例、蛋白比例、蛋壳比例也均有极显著差异（P〈0.01）。在内在品质方面,两种鸡蛋蛋清pH、蛋黄高度、蛋黄系数均无明显差异;珍珠鸡蛋浓蛋白高度比海兰褐鸡蛋的低3.02mm,有极显著差异（P〈0.01）;浓蛋白系数比海兰褐的高0.87,有显著差异（P〈0.05）;珍珠鸡蛋蛋黄颜色比海兰褐鸡蛋的颜色大一个罗氏比色值,有显著差异（P〈0.05）。在营养成分上,以g/枚为单位,珍珠鸡蛋的主要营养成分除胆固醇高于海兰褐鸡蛋外,其他均低于海兰褐鸡蛋。以g/100g为单位,珍珠鸡蛋水分含量明显低于海兰褐鸡蛋,相差12.62（20.21%）,差异极显著（P〈0.01）,脂肪含量也低于海兰褐鸡蛋,差异显著（P〈0.05）,相差1.34（4.4%）,其它营养成分均高于海兰褐鸡蛋。珍珠鸡蛋是较海兰褐鸡蛋小、壳厚、水分含量低、营养丰富的浓缩型蛋,为珍珠鸡蛋的蛋品开发创造了条件。  相似文献   

17.
试验旨在比较笼养和平养方式对不同品种蛋鸭蛋品质的影响,以期为评价不同饲养方式下的鸭蛋品质提供参考依据。随机选取40周龄笼养和平养的金定鸭（青壳蛋）和山麻鸭（白壳蛋）鸭蛋各30枚于产后24 h内进行蛋品质测定。结果表明,同一品种笼养蛋鸭蛋重极显著大于平养蛋鸭蛋重（P<0.01）,蛋重与蛋壳重、蛋白重和蛋黄重之间均存在极显著正相关（P<0.01）,但不同类型鸭蛋的蛋黄重之间差异不显著（P>0.05）。青壳蛋的蛋壳强度显著高于白壳蛋（P<0.05）,笼养青壳蛋的蛋壳强度亦高于平养青壳蛋（P<0.05）。蛋的比重与蛋壳厚度呈极显著正相关（0.503,P<0.01）,与蛋壳强度的相关系数亦达到0.536（P<0.01）。4种类型鸭蛋的哈氏单位均达到72以上。虽然蛋白重与蛋黄重之间呈极显著正相关（P<0.01）,但蛋白重与蛋黄比率之间却呈极显著的负相关（P<0.01）。蛋的比重与蛋黄重和蛋黄比率之间亦存在显著负相关（P<0.05）。以上结果表明,就蛋品质而言,蛋鸭养殖以采用笼养模式、选择青壳蛋鸭品种为宜。  相似文献   

18.
试验采用红(660nm)、绿(560nm)、蓝(480nm)3种发光二极管(处理组)和白炽灯(400～700nm)(对照组),对180羽海兰褐蛋鸡进行人工光照,研究了单色光对蛋重、蛋形指数、蛋长径、短径和蛋壳质量的影响。试验期为19～52周,光强度均为15lx,光照时间为16h。结果表明:在整个试验期,白光组蛋重最高(61.1g),红光组最低(59.2g),二者之间差异显著(P<0.05);38～52周龄,蓝光组蛋长径显著小于其他组,而其短径显著(P<0.05)小于白光组,另外,红光组蛋短径极显著(P<0.01)小于其他组;19～37周龄,绿光组蛋形指数(1.303)显著大于其他组,而38～52周龄,红光组蛋形指数(1.343)极显著(P<0.01)大于其他组;21～45周龄,绿光组蛋壳强度(3.54kg/cm2)极显著(P<0.01)高于白光和蓝光组而绿光组蛋壳厚度(0.368mm)显著(P<0.05)大于其他组;蓝光组蛋壳颜色值(31.6)显著(P<0.05)小于白光组(33.1)。结果提示:蓝光使蛋长、径变短而红光使蛋短径变短,从而使蓝光和红光组蛋重随产蛋周龄而增长的趋势小于白光和绿光组。单色光可影响蛋壳质量,其中绿光组的蛋壳质量最好。  相似文献   

19.
The efficacy of netobimin (Coded SCH 32481, Schering Corporation) in removing naturally acquired gastrointestinal nematode infections was evaluated in 10 treated and 10 untreated (control) yearling beef heifers. The anthelmintic was administered as an oral drench at a dose level of 7.5 mg kg-1 body weight. Fecal egg per gram (EPG) counts were reduced with netobimin by 98% (P less than or equal to 0.01) at both 1 and 2 weeks post-treatment (PT). The compound was highly effective in removing Oesophagostomum radiatum (100% at P less than or equal to 0.01), Cooperia spp. (97.66% at P less than or equal to 0.01) and Nematodirus helvetianus (100%, although not significant), but was ineffective against immature Ostertagia ostertagi (3.19%) and only moderately effective against adult forms (66.14% at P less than or equal to 0.05). The low efficacy against adult O. ostertagi was partially attributed to the maturation of fourth-stage larvae, not removed by the 7.5 mg kg-1 treatment, during the 14-day treatment-slaughter interval. Efficacy against Trichuris spp. could not be evaluated due to low levels and unequal numbers of worms recovered in the groups. The overall efficacy against adult species, excluding Trichuris spp., was 67.40% (P less than or equal to 0.05). No adverse reactions or signs of toxicosis were observed in heifers treated with netobimin.  相似文献   

20.
The purpose of this test was to evaluate the egg quality from two breeds of ducks reared in cages and on floor.30 eggs were chosen from each type of eggs,which were from Jinding (green shell) and Shan Partridge ducks (white shell)at 40 weeks-old reared in cages and on floor for egg quality evaluation.The results showed that the egg weight of caged duck was extremely significantly larger than the floor duck (P<0.01) in the same breed,there were very significant positive correlations between the egg weight and eggshell weight,egg-white weight and egg yolk weight (P<0.01),but no significant difference among the egg yolk weights of different types of ducks (P>0.05).The shell strength of green egg was obviously higher than that of white shell eggs (P<0.05),and the shell strength of green egg from caged ducks was higher than that of the green egg ducks on floor.The correlation coefficients of the egg specific gravity and eggshell thickness,the specific gravity and eggshell strength were 0.503 (P<0.01) and 0.536 (P<0.01) respectively.Haugh units of four types of ducks all reached 72 or more.Although there was significant positive correlation between egg-white weight and egg yolk weight (P<0.01),significant negative correlation was existed between egg-white weight and egg yolk ratio (P<0.01).There were significant negative correlations between egg specific gravity and egg yolk weight (P<0.05) and egg yolk ratio (P<0.05).In conclusion,the mode of cage feeding and the breed with green shell were appropriate choices in laying-egg duck production for high egg quality.  相似文献   

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