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1.
The influence of genotype and stocking densities on growth performance, carcass qualities, and cost-benefits of broilers were examined in a 28-day trial. Two hundred and seven 4-week-old birds each of Anak Titan and Arbor Acre hybrid broiler types were randomly assigned to three stocking density treatments of 8.3, 11.1, and 14.3 birds/m2 in a 2 × 3 factorial arrangement. Final body weight, average weekly body weight and average weekly feed intake were affected (P < 0.05) by strain, with higher means recorded for Arbor Acres. However, average weekly body weight gain and feed conversion ratio were similar (P > 0.05) in both genetic groups. The effect of placement density on some growth parameters did not follow a linear trend. Arbor Acres had significantly (P < 0.05) higher relative (%) fasted body, carcass, back, neck, and wing weights compared to Anak Titans. Housing density effect (P < 0.05) was observed for relative (%) fasted body, shank, and wing weights of birds. However, the relative weights of visceral organs of birds were not significantly (P > 0.05) influenced by genotype and housing density. The economic analysis revealed that higher gross margin was recorded for Arbor Acres compared to Anak Titans (€2.76 versus €2.19; P < 0.05, respectively). Conversely, stocking rate did not exert any influence (P > 0.05) on profit margin. Genotype × stocking density interaction effect was significant for some of the carcass indices investigated. It is concluded that under sub-humid conditions of a tropical environment, the use of Arbor Acre genetic type as well as a placement density of 14.3 birds/m2 appeared to be more profitable.  相似文献   

2.
Three hundred and twenty 1-week old ducklings (160 males and 160 females) were used to evaluate the body weight, body parts and carcass characteristics of the African Muscovy duck. Sexual dimorphism was in favour of the male for all the parameters throughout the experimental period, however the difference was significant (P < 0.05) only after week 2. The 12-week old male weighed 1832.0 ± 180.4 g while the female reached only 68.2% of the male weight. Metatarsus diameter, thoracic perimeter, body length, length of bill, foot and wing in cm were respectively 1.3, 29.5, 57.5, 7.0, 27.1 and 27.8 for the male as compared with 1.2, 25.8, 51.0, 6.3, 23.3 and 26.9 for the female. Body measurements were highly (P < 0.01) correlated with body weight for both sexes, however the highest correlation coefficients were obtained with wing length (0.990 and 0.995) and thoracic perimeter (0.993 and 0.973) for female and male respectively. Live body weight had a linear relationship with both wing length (R2 = 0.991 and 0.81) and thoracic perimeter (R2 = 0.948 and 0.986) for male and female respectively. The female duck yielded higher percent ready-to-cook carcass (66.3%), breast (13.6%), liver (2.8%), heart (1.5%) and gizzard (3.8%) as compared to the male (65.0%, 12.0%, 2.5%, 1.1% and 3.4% respectively) although the difference was not significant (P > 0.05). The male small intestine (185.1 ± 3.4 cm), colon (14.8 ± 1.0 cm) and caecum (17.9 ± 0.4 cm) were significantly (P < 0.05) longer than that of the female (152.2 ± 1.8, 10.8 ± 0.7 and 14.85 ± 0.6 cm respectively).  相似文献   

3.
Growth performances and carcass characteristics of broiler chickens fed diets supplemented with graded levels of Canarium schweinfurthii Engl seed (charcoal A) or maize cob (charcoal B) were studied using a total of 110 3-week-old male chicks. 11 experimental diets including a control and other containing either 0.2, 0.4, 0.6, 0.8 or 1% charcoal from C. schweinfurthii Engl seed (A0.2, A0.4, A0.6, A0.8, and A1%, respectively) or from maize cob (B0.2, B0.4, B0.6, B0.8, and B1%, respectively) supplements were used. Each of the diets was fed to ten individually birds caged in a completely randomized design. Results indicated that birds fed 0.2, 0.4, and 0.6% of either charcoal A or B had significantly (P < 0.05) higher final body weights as compared to control birds, while, above 0.6% slightly depressed average final body weights and weight gain. The best growth performance was achieved with 0.2% inclusion of charcoals. There was no significant (P > 0.05) influence of charcoal B on the overall feed intake. Only the B0.6 feed significantly (P < 0.05) improved feed conversion ratio as compared with the control. Dressing percentage, liver weight and abdominal fat were not significantly (P > 0.05) affected by charcoal. However, there was a significant (P < 0.05) reduction in gizzard weight with charcoal B. Charcoal had no significant (P > 0.05) influence on intestine length and weight. More than 0.6% of charcoal A significantly (P < 0.05) depressed intestine density. It was concluded that under the conditions of this study, charcoal from maize cob or Canarium seeds could be used to improve growth performances and some carcass traits in broiler chickens.  相似文献   

4.
The present study was conducted to evaluate two Indian native chicken breeds, namely, Aseel and Kadaknath for fertility, hatchability, genetic parameters of juvenile growth traits, and semen quality traits at the onset of sexual maturity. The fertility was similar in Aseel (86.96%) and Kadaknath (85.15%); however, a relatively higher hatchability was observed in Kadaknath (77.94%) than Aseel (70.74%). Heritability estimates of body weights at 4 weeks of age were almost similar in Aseel (0.37) and Kadaknath (0.39), while the estimate of body weight at 6 weeks of age was higher in Aseel (0.42) than Kadaknath (0.31). The heritability estimate of shank length at 6 weeks of age was lower in Aseel (0.16) compared to Kadaknath (0.35). The age at first egg in the flock was comparable in Aseel (148 days) and Kadaknath (150 days). Aseel breed with significantly (P ≤ 0.001) higher body weight, absolute and relative testes weights had significantly higher semen volume (P ≤ 0.05) and sperm motility (P ≤ 0.01) but had lower seminal plasma cholesterol level (P ≤ 0.05) as compared to Kadaknath. It can be concluded that there is a scope for genetic improvement of these two native breeds for juvenile growth traits since heritability estimates of these traits were relatively high.  相似文献   

5.
Liveweight (LW) of does and bucks of the native Creole goat breed and crosses of Creole does and Nubian bucks, aged 1.5–5 years, were recorded and body traits including: head length (HL), head width (HW), body length (BL), trunk length (TL), chest girth (CG), abdominal perimeter (AP), rump length (RL), and height at withers (HW) were measured to develop equations for predicting LW from the body measurements. Weight, sex, breed and kidding date of 354 kids were recorded at birth, and LW of the kids was measured monthly for one year to determine the effect of kidding season on growth rate. Bucks had higher (p < 0.05) body measurements than the does (HL 15.1 ± 0.1 vs 16.6 ± 0.2 cm; BL 97.6 ± 0.4 vs 104.6 ± 1.2 cm; CG 78.8 ± 0.4 vs 79.9 ± 1.0 cm; AP 82.4 ± 0.5 vs 87.2 ± 1.1 cm; HW 62.7 ± 0.4 vs 70.1 ± 0.8 cm). With the exception of TL, F2 does had higher (p < 0.05) body measurements and LW (28.8 ± 1.5 vs 27.7 ± 0.5 kg) than Creole does. The body traits of the F1 does were similar (p > 0.05) to those of Creole does with the exception of HL, BL and HR. The F2 kids were heavier (p < 0.05) at birth (3.31 ± 0.1 vs 2.60 ± 0.1 kg) and grew faster than the Creole kids. Male kids were heavier (p < 0.05) at birth (3.21 ± 0.10 vs 2.73 ± 0.13 kg), and grew faster than female kids. Season had a significant effect on birth weight. The results showed that LW of Creole goats and Creole × Nubian does could be estimated in the field using body traits. Birth weight and growth rate of kids could be improved by management practices that affect season of kidding.  相似文献   

6.
The utilization of grain legumes as a protein source for poultry is limited by the presence of antinutritional factors. Various methods have been developed to eliminate them. One hundred and sixty 3-week-old birds of 622 g were used to evaluate the effect of feeding 15% of common beans (Phaseolus vulgaris) either soaked (R1), soaked and extruded (R2) or soaked and heated (R3) and a control (R0) in a completely randomized design. The protein content of the common bean decreased with all the treatments, while the other characteristics remained similar. Feed consumption was highest (p < 0.05) for the R0 birds and lowest for the R3; however, there was no significant difference between R1 and R2 in feed consumption. Body weight gain was comparable for R0 and R2 birds and significantly higher than that of R1 and R3 birds. The control and R2 birds recorded the best feed conversion ratio, while the R1 birds had the poorest (p < 0.05) as well as the highest feed cost for 1 kg body weight. However, there was no difference among the three other groups of birds with regard to cost. All the treatment groups were comparable (p > 0.05) for carcass yield and serum creatinine level. However, the R3 birds had the lowest proportions of liver (2.26%) and heart (1.07%) to body weight.  相似文献   

7.
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.  相似文献   

8.
Habitat fragmentation is globally one of the most important drivers of change in biodiversity. Seed dispersal by birds is crucial for tree regeneration in remnant patchy forests, yet how bird traits affect seed dispersal pattern is still poorly understood. We studied the extent to which bird traits affect seed‐removal networks and whether these traits affect seed deposition and seedling recruitment for 3 co‐fruiting tree species (Taxus chinensis, Cinnamomum bodinieri and Machilus thunbergii) in a patchy forest. A total of 17, 18 and 10 bird species were recorded foraging for seeds of T. chinensis, M. thunbergii and C. bodinieri, respectively. Frequency of bird visitation increased with tail length, wing length and body length. Furthermore, bird body length, bill length, body weight and wing length were important in the strength of the seed removal network. During foraging, 6 bird species exhibited different patterns of microhabitat utilization and their perching frequency increased with bird weight and tarsus length. As a consequence, frequency of habitat use, bird length and tarsus length were important in determining the number of deposited seeds. For seedling recruitment, seedling number increased with bird tarsus length and weight, but decreased with wing length. Overall, our results showed that various bird traits not only affected seed removal, but also influenced the subsequent processes of seed deposition and seedling distribution in a patchy forest. These results thus highlight the importance of large‐bodied birds for plant recruitment and point out the need to prioritize the protection and conservation of these birds in remnant patchy forests.  相似文献   

9.
Two experiments and 3 field trials were conducted to examine the usefulness of a novel bedding material for rearing Large White commercial turkeys. The control bedding was pine shavings (PS) in both experiments and all trials. The novel bedding, aGroChips (AC), is a chopped paper product made from cotton lint waste, gypsum, and old newsprint following a proprietary paper manufacturing process. In both experiments, hens and toms were reared according to typical industry techniques. In the first experiment, use of AC resulted in significantly (P <0.05) heavier toms and hens. In the second, the toms brooded and reared on AC were significantly (P <0.05) heavier than those brooded and reared on PS, whereas toms brooded on one bedding and then reared on the other were intermediate in weight. There were no differences in final cumulative FCR or carcass yield in either experiment. Three field trials were conducted with Large White commercial turkey hens in which the hens were brooded either on PS or AC, with both groups reared on PS. There was a mean increase of 0.2 kg in BW, a decrease (improvement) of 0.03 in FCR, and an increase of 3,200 kg per trial for AC-brooded birds (based on 16,000 hens placed per brooder house). A hard, dry litter crust was observed in the AC houses. With subsequent testing, further changes in the manufacturing process to create a hard, durable pellet may result in a more usable and useful bedding material.  相似文献   

10.
The aim of this study was to evaluate egg production and quality of Rhode Island Red (RIR) laying hens in an outdoor system in the subhumid tropic. Eighty RIR laying hens were measured in two periods and housed randomly under three treatments: outdoor (O), indoor (I) and in conventional cages (C). Egg weight (55.88, 53.76 and 57.16 g, for O, I and C, respectively), food intake/hen/day (138.94, 129.74 and 162.90 g, for O, I and C, respectively) and food efficiency (3.13, 3.22 and 3.96 for O, I and C, respectively) were significantly (P < 0.05) influenced by housing system; however, both egg production and final body weight were not different (P > 0.05). Yolk colour (10.76, 9.94 and 10.08 colour scale, for O, I and C, respectively), albumen weight (92.63, 92.28 and 90.08 g, for O, I and C, respectively) and yolk weight (15.19, 14.61, 15.48 g for O, I and C, respectively) were significantly (P < 0.05) influenced by housing system, but albumen height, Haugh units and egg shell weight remained similar (P > 0.05). Under the conditions of this study, outdoor egg production seems to be a sustainable system comparable to the commercial type based on wired cages.  相似文献   

11.
Genetic analysis for growth traits of prolific Garole × Malpura (GM) sheep   总被引：1，自引：1，他引：0  
The FecB gene of Garole sheep was introgressed into non-prolific Malpura sheep to evolve a new prolific sheep strain Garole × Malpura (GM), suitable for semi-arid conditions. The present study was conducted to evaluate the impact of breeding program on production profile of GM sheep and to estimate the genetic parameters for growth traits of GM sheep. Overall prolificacy increased significantly in the new strain as compared to the native Malpura sheep. In the GM flock of F2 and F2 onwards generation 35.31% single, 55.83% twins, 8.16% triplet and 0.70% quadruplets were obtained during lambing. Over the years, prolificacy in the flock has increased significantly. Over all least squares means for birth weight, 3, 6, 9, 12 month weight, pre-weaning gain (ADG1) and post-weaning gain (ADG2) were 1.82 ± 0.03, 9.44 ± 0.18, 14.00 ± 0.24, 16.56 ± 0.33, and 19.32 ± 0.35 kg, and 84.08 ± 1.84 and 35.19 ± 0.99 g, respectively. Majority of the fixed effects had significant influence on the performance traits. The heritability estimates for birth, 3, 6, 9, 12 month weight, ADG1 and ADG2 were 0.30 ± 0.11, 0.22 ± 0.09, 0.23 ± 0.10, 0.27 ± 0.10, 0.30 ± 0.11, 0.17 ± 0.08, and 0.17 ± 0.10, respectively. Modest rate of genetic progress seems possible for these traits under selection. The genetic and phenotypic correlations among different body weights were moderate to high and positive. The genetic correlation of pre and post-weaning daily gains with body weight traits were also high and positive.  相似文献   

12.
Three experiments were conducted to assess brain damage resulting from percussive bolt shooting and cervical dislocation by crushing (neck crushing) in turkey hens (mean [se] bodyweight 11.4 [0.1] kg); percussive bolt shooting and blunt trauma in turkey toms (13.1 [0.2] kg); and percussive bolt shooting, blunt trauma and cervical dislocation by stretching (neck stretching) in broiler turkeys (3.9 [0.3] kg). Brain and skull damage were assessed using macroscopic and microscopic evaluations and CT. Macroscopic subcutaneous haemorrhage was significantly greater with the percussive bolt in all three experiments (hens P=0.01, toms P=0.02, broilers P=0.0003), and skull fractures were more severe for toms (P<0.0001) and broilers (P=0.03) killed with the percussive bolt versus blunt trauma. In a subsample of turkeys, microscopic brain damage was present in all turkeys killed by percussive bolt shooting (five hens, 10 toms and four broilers) and blunt trauma (nine toms and three broilers), but only in one of four turkeys killed by neck crushing and one of four turkeys killed by neck stretching. Percussive bolt shooting and blunt trauma most likely caused death by directly disrupting brain function, whereas neck stretching and neck crushing probably resulted in death from cerebral hypoxia and ischaemia.  相似文献   

13.
试验测定了5周龄不同羽色麒麟母鸡的体重和体尺性状指标，并进行体重与体尺性状的主成分分析，旨在了解不同羽色麒麟母鸡的体重与体尺性状之间的内在关联性，为其选种选育提供科学依据。本试验选用1日龄健康白羽和黄羽麒麟母鸡各50只，分成2组，每组5个重复，每个重复10只母鸡，在相同饲养条件下饲养5周后，对体重和体尺性状进行测定。结果显示，白羽麒麟母鸡胫长变异系数较大，黄羽麒麟母鸡胫围变异性较大，选育潜力大；白羽麒麟母鸡体重与胫长呈极显著正相关（P < 0.01），相关系数为0.931；黄羽麒麟母鸡体重与胫长为极显著正相关（P < 0.01），相关系数为0.944，体重与胸骨长、胫围，胫长与胸骨长均为显著正相关（P < 0.05）。不同羽色麒麟母鸡的7个体尺性状均可简化为4个主成分，白羽和黄羽麒麟母鸡累计贡献率分别占信息总量的94.784%和94.809%，且简化的4个主成分所占信息的侧重各不相同，均能反映出麒麟母鸡的体型外貌特征。综上所述，自由采食条件下不同羽色麒麟母鸡体重和体尺性状之间存在着显著的相关性，筛选出的白羽和黄羽麒麟母鸡4个主成分均能反映出麒麟母鸡的体型外貌特征，可为不同体型特征麒麟母鸡的选育提供参考。  相似文献   

14.
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.  相似文献   

15.
Data from 82 kiddings from mixed-breed (native x dairy goats) goats reared on rangeland (n = 47) or confinement (n = 35) were used to determine the influence of various factors on length of labour, standing of newborn kids and time to first suckling in pluriparous goats. Both groups were mated at the same time to bucks of the same genotype in February. During the kidding time in July, the goats were monitored for 24 h in order to register parturition traits and kid birth weight and body measurements. For all goats, blood samples were collected at parturition in order to establish the nutritional state of goats. Grazing goats had lower body weight and body condition score (P < 0.01) than pen-fed goats, as well as lower values for some blood metabolites indicative of low body energy reserves. For both grazing and pen-fed goats, the majority of kiddings (>93%) occurred during daylight hours. No kiddings were registered from 2300 to 0500 hours. No effects of height at withers, thoracic circumference and sex of kids at birth were found to influence length of labour. Labour was shorter (P < 0.01) for pen-fed does than grazing goats (10.6 ± 1.18 min vs. 15.4 ± 1.2 min; mean ± SD). The length of parturition was considerably longer (P < 0.05) for twin-bearing does than for single-bearing does (16.6 ± 1.76 min vs. 11.2 ± 0.81 min, respectively). The interval between parturition and standing of kids was shorter (P < 0.05) for kids from litters weighing >3.3 kg (entire litter) than kids from litters with <3.3 kg (22.7 ± 1.82 min vs. 31.1 ± 2.76 min). Time to first suckling was longer (P < 0.05) for kids delivered from pen-fed does than kids from grazing does (57.8 ± 7.57 min vs. 42.9 ± 3.05 min). These results confirm that, independently of type of production system (intensive or extensive), kiddings of does are concentrated during daylight hours. These results also indicate that conformation of kids does not alter duration of labour, and that nutritional stress of goats during gestation (extensive conditions) does not interfere with the neonate’s level of alertness and arousal.  相似文献   

16.
Village chicken production in Turkey: Tokat province example   总被引：1，自引：1，他引：0  
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).  相似文献   

17.
Carcass data base of 164 Creole male goats was used in order to provide factual data on the carcass conformation. Standardised procedures of carcass measuring and cutting were followed. The European official grid of light lamb is implemented for meat goat in the French West Indies and included five levels. Weights of carcass, cuts and tissues, quality scores and linear measurements were analysed. Feeding system, age at slaughter and weight were taken into account for statistical analysis. There were significant differences among carcass conformation classes (CC) for many traits except for the fat score, leg length and compactness ratio (carcass width on length): 2.2, 34.5 cm and 0.30 on average, respectively. The values of chilled carcass weight and yield and the carcass linear measurements steadily increased until conformation class 4 or 5: 6.7 to 11.2 kg, 49% to 55% and 52.4 to 58.0 cm carcass length. For the weights of carcass cuts, significant differences appeared between two groups: classes 1 and 2 vs. classes 3, 4 and 5. Regardless of the carcass weight, the distribution of prime cuts remained similar. The indices calculated on a weight basis (kg/cm), either for the carcass or the leg, increased significantly (P < 0.01): with 54% and 63% difference between the two extreme classes, respectively. The muscle, bone and fat proportions in the shoulder did not vary between CC with 0.72, 0.22 and 0.06, respectively. Corresponding traits in leg were 0.74, 0.23 and 0.03; the last two were different (P < 0.05) from class 1 to class 5. The muscle/bone ratios calculated either in shoulder or in leg ranged from 3.1 to 3.6 (P > 0.05).  相似文献   

18.
The juvenile growth and carcass traits were evaluated in a 4 × 4 full diallel crossing involving four colored broiler chicken lines viz., Naked neck (NN), Dwarf, Punjab Broiler-1 (PB-1), and Punjab Broiler-2 to study the performance and crossbreeding parameters. The data on 2,280 chicks were analyzed using least squares techniques to assess the effect of genetic group, and the significant traits were further analyzed for crossbreeding parameters. Genetic group had significant influence on the body weights and carcass traits. The cross of PB-1 × NN recorded significantly (p ≤ 0.05) higher body weight at 6 weeks of age. The data revealed that general combining ability (GCA), specific combining ability (SCA), maternal ability (MA), sex-linked effect (SE), and purebred effects significantly influenced the growth and carcass traits in the broiler crosses. The crossbred PB-1 × NN showed positive heterosis for growth as well as carcass traits. The results suggest that GCA, SCA, SE, and MA are important in the inheritance of the body weights and carcass traits indicating the presence of both additive and nonadditive genetic variation along with reciprocal effects. Therefore, pure line selection along with development of specialized sire and dam lines followed by crossing will improve the growth performance and benefit the poultry farmers. It is concluded that PB-1 as a male line and NN as a female line performed significantly higher, therefore, may be used for improving the performance of colored broilers.  相似文献   

19.
The effect of total mixed ratios containing wheat middlings (WM) as a corn grain substitute on the growth performance and carcass traits of Comisana ewe lambs was evaluated. Forty ewe lambs, with average live body weight of 13 ± 0.3 kg (mean ± SEM), were allocated randomly to two isocaloric and isonitrogenous diets for 50 days. Control diet contained 400 g/kg of dry matter (DM) of corn as the main starchy source, whereas experimental diet contained 600 g/kg DM of WM. In vivo nutrient apparent digestibility of the two diets was determined using Comisana rams (mean body weight, 65 ± 2.3 kg) and indicated significant (P < 0.05) differences for neutral detergent fibre, acid detergent fibre, cellulose and hemicellulose fractions. Results from the trial using Comisana ewe lambs showed that growth traits were unaffected by dietary treatments as well as none of the carcass measurements examined (P > 0.05). These findings indicate that WM results as a suitable feed ingredient for growing ewe lambs that can be a satisfactory substitute to conventional grain source.  相似文献   

20.
1. Two experimental lines of dwarf brown-egg layers selected on clutch length were reciprocally crossed. In total, 288 hens, from three genotypes: L1, purebred normally feathered (121 hens), F1, crossbred and heterozygous for the NA mutation (99 hens) or L2, purebred homozygous for NA (68 hens) were housed in three climatic rooms at 22 degrees C and three climatic rooms at 32 degrees C. 2. Body weight, daily egg production records, feed intake and some anatomical and physiological traits were recorded. Canonical discriminant analysis was used to examine the relationships among all measured traits and to compare the experimental groups as defined by genotype and temperature. 3. Heterosis effects were observed on body weight, feed intake, egg mass and some anatomical traits at 22 degrees C, but were negligible for most of the traits measured at 32 degrees C except for body weight at 34 weeks, clutch length and some anatomical traits. 4. Genotype by temperature interactions were observed for egg production, egg mass and feed intake. The temperature stress was severe, with a marked decrease in egg production. The naked neck gene could limit the negative effect of long-term heat stress. Egg weight was increased by the NA gene, as usually observed in layers. 5. The first three canonical variates explained altogether 97.4% of the variance. The first canonical variate was associated almost exclusively with ambient temperature. The second was associated with genotype. The third was associated with heterozygous genotype for NA mutation and genotype by temperature interaction. Stepwise discriminant analysis indicated that 12 traits out of 20 were effective at detecting the differences among the genotype and temperature combinations.  相似文献   

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