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1.
The objective of the present study was to determine the effect of broiler breeder egg weight on egg quality, chick quality, and broiler performance using Hubbard Classic broiler breeder flock. Hatching eggs from a commercial broiler breeder flock (Hubbard classic strain) were obtained at the age of 60 wk and divided into 3 egg-weight categories, namely small, medium, and large. For this purpose, 930 eggs having weights 63.09 ± 0.21, 68.85 ± 0.23, and 74.81 ± 0.11g were divided into 3 egg categories labeled small, medium, and large respectively. We further divided these eggs into 2 categories, eggs for quality parameters and eggs for incubation and posthatch performance parameters. Eggs from the small egg category had greater proportion of the shell weight and more shell strength. Egg weight did not significantly affect the albumen and yolk weight percentage. Egg weight affected the shape index and specific gravity for which lower values were observed for large eggs. Egg weight positively affected the chick weight, chick yield, and chick length (P < 0.05) of both male and female chicks. Results of the body weight gain showed that effect of egg weight on the posthatch performance of chick diminishes with the age of broilers. Egg weight significantly affected the body weight gain of male and female chicks up to 3 wk of age. Egg weights did not significantly affect the feed intake and mortality of broiler. Different egg-weight categories significantly affected the feed conversion ratio of female chicks at wk 2 and 3 of age and did not affect the feed conversion of male and female chicks at the end of wk 5. In conclusion, egg weight positively affected the chick characteristics (e.g., chick weight, chick length) and did not affect the final live body weight, feed conversion ratio, feed intake, and mortality in broilers.  相似文献   

2.
(1) Four chick experiments were conducted to determine toxicity estimates for basic zinc chloride (BZC) and basic copper chloride (BCC), now being used as sources for these minerals. (2) In experiment 1, New Hampshire x Columbian crossbred chicks were fed 0, 500, 1000, 1500, 3000 and 5000 mg Zn/kg from BZC (Zn5Cl2(OH)8). Broken-line regression analysis showed that the minimal toxic break points for chick weight gain and gain:food were 1720 and 2115 mg Zn/kg, respectively. (3) Crossbred chicks were fed 0, 150, 250, 500, 750 and 1000 mg Cu/kg from BCC (Cu2(OH)3C) in experiment 2. Regression analysis indicated that the minimal toxic break points for chick weight gain and gain:food were 642 and 781 mg Cu/kg, respectively. (4) In experiment 3, commercial broiler chicks were fed 0, 1500, 2000 and 2500 mg supplemental Zn/kg from BZC or 0, 500, 650 and 800 mg supplemental Cu/kg from BCC. Broiler chicks fed those high inclusion rates of Zn did not show reduced weight gain in comparison to chicks fed no supplemental Zn. All high concentrations of supplemental Cu depressed chick weight gain in comparison to control chicks. (5) Experiment 4 involved two separate 4 x 2 factorial designs with supplemental Zn (0, 2500, 3500 and 4500 mg/kg) or Cu (0, 500, 750 and 1000 mg/kg) and two breeds of chicks (crossbred and commercial). Significant interactions for weight gain, food intake, gain:food and liver Cu suggested that the crossbred and commercial chicks responded differently to high concentrations of supplementary dietary Cu.  相似文献   

3.
Several bioassays were conducted with young chicks and pigs fed phosphorus (P)-deficient corn-soybean meal diets. With diets for chicks containing .62% Ca and .42% P (.10% available P), graded doses of a citric acid + sodium citrate (1:1, wt:wt) mixture (0, 1, 2, 4, or 6% of diet) resulted in linear (P < .01) increases in both weight gain and tibia ash. Relative to chicks fed no citric acid, tibia ash (%) and weight gain (g/d) were increased by 43 and 22%, respectively, in chicks fed 6% citric acid. Additional chick trials showed that 6% citric acid alone or sodium citrate alone was as efficacious as the citric acid + sodium citrate mixture and that 1,450 U/kg of phytase produced a positive response in bone ash and weight gain in chicks fed a diet containing 6% citrate. Varying the Ca:available P ratio with and without citrate supplementation indicated that citric acid primarily affected phytate-P utilization, not Ca, in chicks. Moreover, chicks did not respond to citrate supplementation when fed a P-deficient (.13% available P), phytate-free casein-dextrose diet. Young pigs averaging 10 to 11 kg also were used to evaluate citric acid efficacy in two experiments. A P-deficient corn-soybean meal basal diet was used to construct five treatment diets that contained 1) no additive, 2) 3% citric acid, 3) 6% citric acid, 4) 1,450 U/kg phytase, and 5) 6% citric acid + 1,450 U/kg phytase. Phytase supplementation increased (P < .01) weight gain, gain:feed, and metatarsal ash, whereas citric acid addition increased only gain:feed (P < .05) and metatarsal ash (P < .08). A subsequent 22-d pig experiment was conducted to evaluate the effect of lower levels of citric acid (0, 1, 2, or 3%) or 1,450 U/kg phytase addition to a P-deficient corn-soybean meal diet. Phytase supplementation improved (P < .01) all criteria measured. Weight gain and gain:feed data suggested a response to citric acid addition, but this was not supported by fibula ash results (P > .10). The positive responses to phytase were much greater than those to citric acid in both pig experiments. Thus, dietary citric acid effectively improved phytate P utilization in chicks but had a much smaller effect in pigs.  相似文献   

4.
This study examined the utility of serial weights from FIRE (Feed Intake Recording Equipment, Osborne Industries, Inc., Osborne, KS, USA) stations for an analysis of daily gain. Data included 884 132 body weight records from 3888 purebred Duroc pigs. Pigs entered the feeder station at age 77–149 days and left at age 95–184 days. A substantial number of records were abnormal, showing body weight close to 0 or up to twice the average weight. Plots of body weights for some animals indicated two parallel growth curves. Initial editing used a robust regression, which was a two‐step procedure. In the first step, a quadratic growth curve was estimated assuming small or 0 weights for points far away from the curve; the process is iterative. In the second step, weights more than 1.5 SD from the estimated growth curve were treated as outliers. The retained body weight records (607 597) were averaged to create average daily weight (170 443) and then used to calculate daily gains (152 636). Additional editing steps included retaining only animals with ≥50 body weight records and SD of the daily gain ≤2 kg, followed by removing records outside 3 SD from the mean for given age, across all the animals – the resulting data set included 69 068 records of daily gain from 1921 animals. Daily gain based on daily, weekly and bi‐weekly intervals was analysed using repeatability models. Heritability estimates were 0.04, 6 and 9%, respectively. The last two estimates correspond to heritability of 28% for a 12 week interval. For daily gain averaged weekly, the estimate of heritability obtained with a random regression model varied from 0.07 to 0.10. After extensive editing, body weight records from automatic feeding stations are useful for genetic analyses of daily gain from weekly or bi‐weekly but not daily intervals.  相似文献   

5.
1. Cysteamine hydrochloride, which is a potent inhibitor of somatostatin secretion, was fed to male broiler chicks at dietary inclusion rates of 0, 25, 125, 250, 600, 1200, 1800 and 2400 mg/kg during three separate experiments. 2. Weight gain, food intake and efficiency of food utilisation were measured weekly over a two (experiment 1 and 2) or three-week period (experiment 3) during which chicks were 3 to 10 d old (week 1) to 17 to 24 d old (week 3). 3. Cysteamine hydrochloride included in the food at 1200 and 1800 mg/kg resulted in a significant increase in efficiency of food utilisation, attributable to a significant decrease in food intake. 4. There was no difference in weight gains between chicks in the control group and those receiving 1200 mg/kg. However a significant decrease in weight gain was observed in chicks receiving 1800 mg/kg.  相似文献   

6.
The aim of the current study was to examine the effects of clenbuterol injection into newly hatched chicks on both the abdominal fat pad tissue weight and the skeletal muscle weight during subsequent growth. Twenty‐seven 1‐day‐old chicks were divided into two groups, receiving either a single intraperitoneal (i.p.) injection of clenbuterol (0.1 mg/kg body weight) or phosphate‐buffered saline (PBS). Body weight gain, feed intake and feed conversion ratio were not affected by clenbuterol injection during the 5‐week experimental period, while the abdominal fat pad tissue weight of the clenbuterol‐injected chicks was lower than that of the control chicks at 5 weeks post‐injection. Plasma non‐esterified fatty acid concentrations were significantly increased in the clenbuterol‐injected chicks, while plasma triacylglycerol concentrations did not differ. Additionally, the enzymatic activity of fatty acid synthase was lower in the liver of the clenbuterol‐injected chicks. Conversely, the skeletal muscle weights were not affected by clenbuterol injection. These results suggest that a single clenbuterol injection into 1‐day‐old chicks decreases the abdominal fat pad tissue weight, but may not affect skeletal muscle weights during growth. © 2015 Japanese Society of Animal Science  相似文献   

7.
Six-hundred-and-seven-day-old chicks were generated from Nigerian local chickens consisting of three genotypes (Normal-feathered; Frizzled-feathered; Naked neck) and an exotic broiler breeder (Anak Titan) to evaluate growth performance for possible meat-type chicken development. Growth parameters measured were body weight, breast girth and keel length on weekly basis for 20 weeks. Effects of sire, dam and chick genotypes were significant (P < 0.001) on growth traits. At week 20, chickens sired by the Anak Titan weighed 1,614.82 g followed by Normal-feathered local chickens with body weight of 1,211.32 g. Progenies of Anak Titan and Naked neck dams weighed 1,761.96 and 1,292.80 g at week 20, respectively. Among purebreds, Anak Titan weighed 35.05 g at day-old and had heaviest body weight of 2,360.29 g at 20 weeks compared to the three local strains. The average body weights for the crossbred, Normal-feathered×Anak Titan at day-old and week 20 were 36.39 and 1,577.63 g, respectively. This was followed by Anak Titan×Naked neck with 33.32 g at day-old and 1,514.14 g at week 20. Sex had significant effect (P < 0.05) at weeks 16 and 20 with the males having higher mean values than their female counterparts. This study revealed that crosses involving Anak Titan sire×Naked neck dam had highest growth performance, and there was no strain differences among the growth performance of purebred Nigerian local chickens.  相似文献   

8.
选择健康华北柴鸡商品雏200只为试验材料,饲养期共16周,在初生和各周龄末空腹称重,计算各周绝对增重、相对增重。从研究结果看,华北柴鸡体重的绝对增重在8周龄最高,公鸡与母鸡虽然增重数值略有差异,但生长高峰出现的时间基本相同。  相似文献   

9.
The "available" tryptophan requirements of male and female broiler chicks were determined at 7-d intervals from 0 to 56 d, using a diet-dilution technique. Availability of tryptophan in the diets was estimated by growth assay with chicks. 2. The tryptophan requirements were 2.4 (males) and 2.2 g/kg of diet (female) from 0-7 d, and 1.7 g/kg (males and females) from 7-35 and 35-56 d. The absolute requirement of the chick for tryptophan increased with age and was significantly different for male and female birds. 3. A highly significantly predictive equation relating tryptophan requirement to mean body weight and gain was established.  相似文献   

10.
试验选用1日龄雌性古典型岑溪三黄鸡1080只,平均分成9个处理,每个处理设3个重复,每个重复为40只,用9种不同的处理日粮,进行为期6周的饲养试验。试验结果表明,能量对古典型岑溪三黄鸡的采食量、增重和料重比影响差异显著（P<0.05）,蛋白质和含硫氨基酸对古典型岑溪三黄鸡的增重、采食量和料重比影响差异不显著（P>0.05）。以增重为衡量指标,能量、蛋白质和总含硫氨基酸水平分别以12.13 MJ/kg、20%和0.97%对古典型岑溪三黄鸡最佳。   相似文献   

11.
OBJECTIVE: To follow the development of the refractive error in the eyes of ostrich chicks from age 0 to day 37 after hatching. ANIMALS: 35 ostrich chicks. PROCEDURES: Spot retinoscopy was conducted to assess refractive error in ostrich chicks. Seventy eyes of 35 ostrich chicks were examined. Of these, 18 chicks were followed over time. At least 4 serial measurements (at 2- to 7- day intervals) were conducted in each of these chicks from day 1 to 37 after hatching. Seventeen additional chicks were examined on days 0, 3, 12, and 19 after hatching. RESULTS: Ostrich chicks were myopic at hatching, with a mean +/- SD refractive error of -4.47 +/- 0.15 diopters (D). The refractive error rapidly decreased during the first week of life, and by day 7 after hatching, chicks were slightly hyperopic, with a mean refractive error of 0.42 +/- 0.12 D. After day 7, there were no significant differences in the mean refractive error. CONCLUSIONS: The development of optics in the ostrich eye appears to be unique among animals and is characterized by myopia at hatching, rapid onset of emmetropia, and minimal variation in refractive error among chicks.  相似文献   

12.
1. A total of 4000 Ross broiler breeders were reared to a 20-week target body weight of 1.55, 2.16 (standard), 2.50 or 2.84 kg, using either a convex or concave growth curve. Each treatment group was either exposed to a conventional broiler breeder lighting regimen, with a series of weekly one-hour increments in photoperiod from 8h at 19 weeks to a 16-h maximum, or maintained from 4d on a 17-h photoperiod. 2. Each 100 g increment in body weight at 20 weeks was associated with a significant increase of 0.55 kg in cumulative food intake, and a 1.5-d advance in sexual maturity. However, leaner body weights at 20 weeks resulted in smaller body weight gains between 20 and 60 weeks (-2.4 g/d/kg body weight at 20 weeks), and an increased production of double-yolked eggs. Neither egg production nor mean egg weight was affected by 20-week body weight. 3. Birds fed to produce more rapid early growth had higher feed intakes to 20 weeks, but reached sexual maturity 7 d later than birds permitted accelerated growth from 15 weeks. Growth curve did not influence body weight gain in lay, egg production or mean egg weight. 4. Birds maintained on 17-h photoperiods reached sexual maturity 27 d later, produced 7 fewer eggs to 60 weeks, and had a mean egg weight 1.2 g heavier than birds photostimulated at 19 weeks. Lighting treatment did not affect food intake to 20 weeks, the proportion of double-yolked eggs or body weight gain between 20 and 60 weeks. 5. Birds fed to have a faster growth early in the rearing phase and maintained on 17-h photoperiods produced 11 fewer eggs than those fed to have accelerated growth at the end of the rearing phase, yet there was only one egg difference between the growth-curve groups for the conventionally lighted birds, which was not significant. 6. The earlier sexual maturity of the conventionally lighted birds compared with those maintained on 17-h photoperiods either indicates that broiler breeders require an increment in photoperiod to stimulate rapid gonadal development or that broiler breeders exhibit juvenile photorefractoriness that takes longer to be dissipated when birds are not given a period of short days. 7. The findings suggest that a nutritional stimulus late in rearing is only necessary for satisfactory egg production if birds have not received a concurrent increment in photoperiod.  相似文献   

13.
1. The productive performance of 4 chicken breed groups managed under semi-intensive conditions in Yucatan, Mexico was evaluated. Thirty-six mixed chickens, one week of age of each of the 4 breed groups (Creole, F1 Hubbard x Creole, 7/8 Hubbard x 1/8 Creole and Hubbard) were used. 2. During 1 to 3 weeks of age all birds were fed on a diet containing 210 g/kg crude protein (CP) and 12.95 MJ/kg metabolisable energy (ME). From weeks 4 to 7, they were given a diet with 190 g/kg CP and 12.55 MJ/kg ME. Food consumption and live body weight were recorded weekly. Statistical analysis of the data was performed according to complete randomised design and means comparison using Tukey test was carried out when necessary. 3. Creole chicks had the lightest weights at all ages as compared to their crosses and the Hubbard birds. At 7 weeks of age, Creole chicks were 2.11, 2.44 and 2.90 times lighter than their contemporary F1, 7/8 Hubbard x 1/8 Creole and Hubbard birds, respectively. Hubbard birds were heavier than F1 and 7/8 commercial x 1/8 Creole birds, and the latter group heavier than the F1 birds. Similarly, Creole chicks had the lowest growth rate compared to the other genetic groups. Heterosis for body weight up to 7 weeks of age was 8.2%. 4. Feed consumption was also lower for the Creole chicks at all ages. Food:gain ratio, however, was higher for the Creole chicks at all ages. Food:gain ratios from weeks 2 to 7 were 2.18, 2.65, 3.04 and 4.36 for the Hubbard, 7/8 Hubbard x 1/8 Creole, F1 and Creole birds, respectively. Heterosis for food:gain ratio from 2 to 7 weeks of age was -7.0%. 5. Crossbreeding of Mexican Creole birds with commercial type broilers might improve productive performance.  相似文献   

14.
Three experiments were conducted to study the effects of broiler strain and phytase supplementation on chick nonphytate P (NPP) requirements for growth, feed intake, and tibia ash. The first experiment compared the NPP requirements for 8- to 22-d-old chicks from 2 broiler strains, Ross 308 and 708, that have been selected for differences in early weight gain and performance. The second experiment utilized similar 8- to 22-d-old Ross 308 and 708 chicks but also compared the effects of dietary fungal phytase supplementation (600 U/kg) on broiler NPP requirements. The third experiment utilized a younger starting age, 5 to 23 d old, for Ross 308 and 708 chicks with and without phytase supplementation. Minor differences in chick growth did not affect chick NPP requirements in Experiments 1 and 3, but a substantial and unexplained reduction of growth of the Ross 708 chicks in Experiment 2 resulted in a lower NPP requirement for chick growth and feed intake but not for tibia ash. As expected, supplementation of diets with fungal phytase did result in decreased NPP requirements for growth, feed intake, and tibia ash in both strains used in Experiment 3.  相似文献   

15.
选用1日龄爱拔益加肉仔鸡健康雏鸡240只，分性别进行饲养试验和比较屠宰试验。在42d的试验期内，每间隔7d测定试验鸡的体重及相应的体组成。采用Gompertz方程拟合公母肉仔鸡的生长曲线，并通过不同数学公式分别描述肉仔鸡胴体蛋白重和羽毛蛋白重与活重的关系，筛选出最佳模型并与生长曲线组合。分别对生长曲线和筛选的模型进行微分，建立活体增重、胴体蛋白沉积量、羽毛蛋白沉积量与日龄之间的动态函数关系，精确反映肉仔鸡的生长和蛋白质沉积规律。  相似文献   

16.
The work describes the effects of cimetidine on stress-induced gizzard erosions (Experiment A) and the influence of the long-term application (42 days) of the same drug on weight gain and feed consumption during broiler fattening (Experiment B). For Experiment A, 60 male, three-day-old chicks were divided into two groups: C (n = 30)--control chicks treated with 0.5 ml saline; CIM (n = 30)--chicks treated with cimetidine in a dose of 5 mg/kg body weight (b. w.) intragastrically. All chicks were stressed using a modified water-immersion stress method according to which the chicks, after 24 h of feed deprivation, were immersed in tap water (17 degrees C) for a few seconds. Under chloroform anaesthesia ten chicks from each group were killed 1, 2 and 3 h after the stressing. The morphometric analysis of gizzard erosion (GE) and histopathological examinations of gizzards were performed for each chick. In Experiment B, 32 one-day-old broilers of both sexes were used. The control group was untreated (n = 16) while the CIM group (n = 16) was fed the same diet supplemented with 10 mg of cimetidine per kilogram of feed throughout the fattening period (42 days). The results of Experiment A showed decreased mean length of the GE in the cimetidine-treated birds as compared with the GE lesions of the controls. In Experiment B, the treated chicks had reduced liveweight (1835.1 g), carcass weight (1474.6 g) and increased feed consumption (2115 g of feed per kilogram of weight gain) compared to the controls in which the same parameters were 1898.5 g, 1574.2 g and 1797 g, respectively. The results show that while stress-induced GE of chicks can be medicated pharmacologically, long-term application of the same substance impairs the results of fattening.  相似文献   

17.
1. The effect of egg weight on the subsequent performance of individual growing chicks was studied. Eggs from commercial broiler breeder hens were collected at 52, 55 and 57 weeks of age and incubated. The chicks were reared for 18 d. 2. Egg weight and hatched chick weight were not affected by the age of the hens during the 52 to 57-week period, but there was a close correlation between egg weight and hatching weight, irrespective of the age of the hens (r = 0.89). Chick:egg weight ratio at hatching was about 0.71 and independent of hen age. One d after hatching, chick weights had decreased by about 1.5 g. 3. The initial high correlation between egg weight and chick weight decreased markedly during post-hatching growth, becoming insignificant 5 d after hatching. At 18 d of age, however, chicks from eggs of older hens tended to be heavier than those from younger birds. The greater 18-d weights appeared to be associated more with higher food intake during that period, than with greater egg weight. 4. It was concluded that, in individual broiler chicks, the advantage of the initially higher weight attributable to a larger egg diminishes rapidly after hatching, and the main factor affecting final body weight is food intake.  相似文献   

18.
Jackass penguins Spheniscus demersus hatch two different-sized eggs asynchronously: the second-hatched chick, being, on average, 59% of the weight of the first-hatched chick on hatching. We examined the effect of hatching order on growth rates of mass, culmen length and culmen depth by comparing: (i) growth rates of first-and second-hatched chicks, and (ii) chicks from experimentally synchronized broods to chicks from normal asynchronous broods. Only growth rates in mass showed significant variation. Within a brood, B chicks grew more slowly than A chicks. The effect of synchronizing a brood was to lower the growth rate of both chicks to that of a B chick, suggesting that equal-sized siblings feed less efficiently. Chicks hatching from larger A eggs, that had been synchronized for age and size with chiçks from B eggs, did not grow faster, indicating that chicks hatching from A and B eggs do not have intrinsically different growth rates. Single-chick nests result usually from egg infertility. Singletons showed only a non-significant trend towards faster growth in mass than offspring in two-chick broods, even though food availability in one-chick nests should be better than in two-chick nests. Overall, hatching order had more impact on growth rates of mass than did brood size or egg dimensions.  相似文献   

19.
在蛋雏鸡育雏期添加金蟾速补钙（畜禽钙锌预混料）进行饲喂,观察育雏期每周鸡群采食量和雏鸡死亡数,并按2%比例抽样称重,计算鸡群均匀度。结果试验组雏鸡质量和鸡群均匀度明显优于对照组,差异显著（P〈0.05）;试验组采食量和雏鸡总死亡数高于对照组,但差异不明显。试验结果提示,在蛋鸡育雏期使用金蟾速补钙（畜禽钙锌预混料）可以提高育雏生产性能,可在生产上推广应用。  相似文献   

20.
In an 18-month study the domestic fowl in 42 households in three traditional management systems were recorded to determine reproduction, growth and mortality parameters. There were significant differences for all systems combined in the number of clutches started per month with the lowest number being laid in the cool dry season of January and February. Mean number of eggs per clutch was 8.8; the number of eggs increased significantly throughout the career of the hen but there were no significant systems differences. Egg weight was 34.4g there being no significant differences due to age of hen or system. Intervals between clutches were 92 days, annual egg output was 35 per hen (assuming that birds were present in the flock for a year) equivalent to about 118% of mean adult hen body weight: hens actually in the flocks during the study had produced 2.1 clutches on average. Hatchability of eggs was 69.1% there being significant seasonal and systems differences in this parameter, lowest hatchability being in the hot dry season (March to June) and in the rainfed millet system. Mortality rates to eight weeks were 56% of chicks hatched. Growth to 10 weeks averaged 4g/d. Mature cocks weighted 1.60 kg and mature hens 1.02 kg: hen weights were significantly affected by reproductive state, laying hens being heavier than both incubating hens and those rearing chicks, while those rearing chicks were heavier than those incubating. Suggestions for improving productivity are made.  相似文献   

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