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1.
ABSTRACT 1. Changes in feather length and weight and daily losses of down, contour feathers, remiges and retrices were studied in two commercial broiler strains to determine feather growth and moult in broilers up to 112 d of age. 2. Ten pens of 20 chicks for each sex x strain were fed adequate amounts of dietary protein in a four-phase feeding programme. Ten birds were sampled per genotype at 14, 28, 42, 56, 70, 84, 98 and 112 d. Feather loss was determined for individual birds caged within a nylon net. 3. All feathers were dry-plucked from each of seven tracts, with representative feathers from the capital-cervical, dorsopelvic and interscapular, pectoral and femoral tracts being randomly selected. Three rectrices of the dorsocaudal tract and three primaries and secondaries of the humeral-alar tract of the right wing were evaluated. 4. The length of the selected feathers was measured, and the feathers from each tract and from the whole bird were weighed. 5. A wide range of rates of maturing (0.0250–0.0907/d) and mature weights (9.62–52.9 g) were evident between sampled tracts. 6. Feather weight failed to predict some moults which were detected by the measurement of feather losses. From the weight data, moulting was evident only in the humeral-alar and dorsocaudal tracts, whereas, when daily losses were measured, contour feathers accounted for over 0.7 proportion of feather losses. Logistic equations adequately described the cumulative losses of down, contour feathers and remiges. 7. Feather loss needs to be considered when feather growth is determined from feather weight at different ages. 8. The rate of maturing (B) of feathers was numerically higher in Ross males and females than in the Cobb strain. In females, B was higher than in males (0.0483 vs. 0335/d) but the mature weight was lower (162 vs. 230 g). 相似文献
2.
ABSTRACT1. The relationships between the main components of the body and body protein among males and females of BUT 6 (BUT) and Hybrid Converter (HYB) turkey strains were examined.2. The weights of breast meat, breast skin, drumstick meat, drumstick skin, thigh meat, thigh skin and wing-plus-skin as well as the head, neck, feet, blood, heart, liver and gizzard were measured at different stages of growth after which all components of each bird were minced together in order to determine the feather-free body protein weight of each bird sampled. Using the weights of the components and the protein content of each bird the allometric relationships between the components and body protein were determined and then compared for each strain x sex combination.3. By excluding the breast weights at day-old and at 7 d, the remaining points produced an acceptable allometric relationship (R 2 = 0.992). Thigh weight could be predicted for all strain x sex combinations using one allometric equation, as could drumstick skin weight. Breast and thigh skin weights differed between males and females. Females of the HYB strain exhibited heavier drumstick and wing-plus-skin weights at a given body protein weight than the other three strain x sex combinations. These differences in both the constant term and regression coefficient in the allometric equations between genotypes are probably due to differences in the amount of lipid that is deposited in these tissues.4. Sexes differed in the allometric relationships for head, feet, heart and liver, while breeds differed in gizzard weight. A common relationship between the four genotypes could be used to predict the weight of blood in the carcass.5. The allometric equations fitted to the data in this trial enable the accurate prediction of the weights of the different physical components given the weight of body protein. 相似文献
5.
1. This study aimed to provide information on the response of laying-type pullets to dietary threonine (THR) during three periods of growth prior to the onset of lay. Different batches of Dekalb White pullets were used in three separate trial periods (from 4 to 6, 8 to 11 and 13 to 16 weeks of age) using 8 dietary THR concentrations in each period, using a completely randomised design, and with each treatment being replicated 6 times, using 15 birds per replication in period 1 and 8 birds in periods 2 and 3. In period 1 the THR content (THRc) ranged from 2.3 to 7.6 mg/g, in period 2 from 1.7 to 5.5 mg/g, and in period 3 from 1.4 to 4.7 mg THR/g feed. 2. Body weight gain, food intake and the deposition of protein and lipid in the feather-free body and in the feathers were measured in each period. Linear regressions were fitted to all data falling below the break point defined by the broken stick regression, to estimate the efficiency of utilisation of THR. The maximum protein growth rate was 4.0 ± 0.2, 5.3 ± 0.4 and 3.5 ± 0.5 g/d in periods 1, 2 and 3, respectively. 3. The efficiency of utilisation of dietary THR for THR deposition in each period was the same, at 0.85 ± 0.1 mg/mg. As dietary THRc decreased, the amount of body lipid deposition increased. 4. With this information, it is possible to determine the daily requirement for THR for the potential growth of body and feather protein in growing pullets. 相似文献
7.
The objective of this study was to estimate growth parameters of carcass components (wing, thighs and drumsticks, back and breast) and organs (heart, liver, gizzard and gut) in males and females of one meat-type quail strain (Coturnix coturnix coturnix) and two laying strains (Coturnix coturnix japonica) designated either yellow or red. A total of 1350 quail from 1 to 42 d old were distributed in a completely randomised design, with 5 replicates of each strain. The carcass component weights and body organs were analysed weekly and evaluated using the Gompertz function; growth rates were evaluated through derivative equations. The meat-type strain presented the highest growth rates in carcass components and organs. Across strains, females showed the highest weight of internal organs at maturity compared to males. Females had greater growth potential in breast, wings and back than males for both yellow and red laying quail.
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8.
1. A genome-wide scan of 467 F 2 progeny of a broiler x layer cross was conducted to identify quantitative trait loci (QTL) affecting the rate of growth of the tail, wing and back feathers, and the width of the breast feather tract, at three weeks of age. 2. Correlations between the traits ranged from 0·36 to 0·61. Males had longer tail and wing feathers and shorter back feathers than females. Breast feather tract width was greater in females than males. 3. QTL effects were generally additive and accounted for 11 to 45% of sex average feather lengths of the breeds, and 100% of the breast feather tract width. Positive and negative alleles were inherited from both lines, whereas the layer allele was larger than the broiler allele after adjusting for body weight. 4. A total of 4 genome-significant and 4 suggestive QTL were detected. At three or 6 weeks of age, 5 of the QTL were located in similar regions as QTL for body weight. 5. Analysis of a model with body weight at three weeks as a covariate identified 5 genome significant and 6 suggestive QTL, of which only two were coincident with body weight QTL. One QTL for feather length at 148?cM on GGA1 was identified at a similar location in the unadjusted analysis. 6. The results suggest that the rate of feather growth is largely controlled by body weight QTL, and that QTL specific for feather growth also exist. 相似文献
9.
1. The influence of gender on chemical composition, physicochemical parameters, fatty acid profile, amino acid and mineral composition of turkey breast and thigh meat was studied in order to assess nutrient requirements. 2. Chemical composition showed that only intramuscular fat in breast meat was significantly affected by gender (p < 0.05). The results showed a higher percentage of intramuscular fat in male samples, almost double the amount found in females (0.73% vs. 0.38%). 3.For meat colour parameters, only a* showed different results between sexes, with male samples (breast: p < 0.01; thigh: p < 0.001) having the highest values. 4. Fatty acid profiles showed that medium chain unsaturated fatty acids were the most abundant. The significant differences (p < 0.05) found in both breast and thigh muscle could be linked to a difference in metabolism between males and females. 5.There were higher levels of C16:1n-7 in females (breast: p < 0.001; thigh: p < 0.01) compared with male muscle sample (5.05 vs. 2.67 g/100 g in breast and 4.95 vs. 3.27 g/100 g in thigh). Nutritional indices (n-6/n-3 and thrombogenic index) were more favourable in female samples demonstrating that female turkeys had better fatty acid profile than the others. 6. Turkey meat is an important source of dietary amino acids, and female samples had the highest contents both of essential and non-essential amino acids. Furthermore, gender had a numeric effect (p > 0.05) on amino acid composition. 7. Mineral composition showed that Na, Zn and Fe were the minerals most affected by turkey gender. 相似文献
10.
1. Feathers are recalcitrant protein-rich wastes produced in huge amounts by poultry processing for meat production. Hence, feather bioconversion and protease production by Bacillus sp. CL18 were investigated.2. Bacillus sp. CL18 demonstrated a remarkable feather-degrading potential. Through cultivations on feather broth (10 g l ?1 feathers), 94.5% ± 3% of whole feathers were degraded after 4 d. Increases in soluble protein contents were observed and protease production was maximal also at d 4. This strain produced diverse proteolytic enzymes during growth.3. Crude protease displayed optimal activity at 55°C (50–62°C), pH 8.0 (7.0–9.0) and a low thermal stability. Proteolytic activity increased in the presence of Ca 2+, Mg 2+, Triton X-100, Tween 20 and dimethyl sulphoxide. Inhibition profile indicated that crude protease contains, mainly, serine proteases. Enzyme preparation hydrolysed mainly casein and soy protein isolate.4. The keratinolytic capacity of Bacillus sp. CL18 at moderate temperatures (30°C) might be appropriate for feather conversion, resulting in protein hydrolysates and proteolytic enzymes. Proteases are postulated to be added-value products that can be obtained from such a bioprocess. 相似文献
11.
1. AT-402 (20 g/kg), a proprietary blend of Aloe ferox leaf extract and calcium bentonite, had no adverse effect on poult body weights at 3 weeks of age. 2. Lower body weights and lower feed consumption were observed in 4-week-old poults given 10 and 20 g/kg of AT-402 compared to poults given 0 or 5 g/kg. 3. Floor-reared poults, given either 5 or 10 g/kg AT-402 to 4 weeks of age, were significantly heavier than controls (0 g/kg AT-402), and feed conversion ratios for AT-402 given poults were improved. 4. Xylose uptake in 5 g/kg AT-402-fed poults was significantly greater than in poults given AT-402 at 0 and 10 g/kg, reflecting increased body weights of 5 g/kg AT-402-fed poults. 5. Delayed access by poults to the AT-402 until 10 d of age also improved 4-week body weights, suggesting that the AT-402 might improve performance as soon as it is given. 6. AT-402 at 5 g/kg was most efficacious as demonstrated by improved body weights and feed conversions. 相似文献
12.
The Richards growth model was fitted to body weight-age data of local and SASSO T44 chickens to describe their growth performance.
Males had higher ( P < 0.05) asymptotic mature weights than females. Within the local chicken population, birds from the savannah zone had higher
( P < 0.05) asymptotic mature weights compared to forest chicken which ironically had higher body weights at hatch. Male local
chicken had lower maturing rates compared to the females. Female local chicken were superior to SASSO T44 females in terms
of maturing rate. On the average, local chickens took relatively longer time (78.4–83.3 days) to reach the point of inflection
than the SASSO T44 population (74.2–79.8 days). However, there were no significant differences ( P > 0.05) in the age at inflection among local chicken populations. The shape parameter for SASSO T44 chicken (0.053–0.370)
and maturation rate for local chicken (0.177–0.198) were the most critical parameters. Scaling the body weights into degree
of maturity highlighted the degree to which genotypes matured over time. Female chickens had the highest ( P < 0.05) degree of maturity at all ages. The local chicken populations were also metabolically older than SASSO T44 chickens.
Results of this study provide an opportunity to develop breeding strategies for local chicken by modifying either management
practices or their genetic makeup to positively affect their growth and productivity. 相似文献
13.
The aim of this study was to determine the antibiotic susceptibility of 93 Lactobacillus strains isolated from domestic geese raised on Polish farms. The minimal inhibitory concentration (MIC) of 13 antimicrobial substances was determined by the broth microdilution method. All strains were sensitive to the cell wall inhibitors ampicillin and amoxicillin (MIC ≤ 8 μg/ml). Resistance to inhibitors of protein synthesis and to fluoroquinolone inhibitors of replication was found in 44.1% and 60.2% of isolates, respectively; 26.9% strains were resistant to neomycin (MIC ≥ 64 μg/ml), 23.6% to tetracycline (MIC ≥ 32 μg/ml), 15% to lincomycin (MIC ≥ 64 μg/ml), 18.3% to doxycycline (MIC ≥ 32 μg/ml), 9.7% to tylosin (MIC ≥ 32 μg/ml), 56% to flumequine (MIC ≥ 256 μg/ml) and 22.6% to enrofloxacin (MIC ≥ 64 μg/ml). Bimodal distribution of MICs indicative of acquired resistance and unimodal distribution of the high MIC values indicative of intrinsic resistance were correlated with Lactobacillus species. Eleven (11.8%) strains displayed multiple resistance for at least three classes of antibiotics. Data derived from this study can be used as a basis for reviewing current microbiological breakpoints for categorisation of susceptible and resistant strains of Lactobacillus genus and help to assess the hazards associated with the occurrence of drug resistance among natural intestinal microflora.
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14.
Milanino is a heavy Italian chicken breed included in a conservation project of the University of Milan and is an important genetic resource for alternative production systems. This research was aimed to study the effect of the dietary protein concentration on growth, slaughter performance and meat composition in free-range reared Milanino chickens. A total of 120 Milanino chickens were fed on different protein concentrations (HP = 20% CP and LP = 16% CP), reared according to a free-range system and slaughtered at 150 and 180 d of age. Growth, slaughter performance and meat (breast and thigh) composition were recorded. The protein concentration of the diet did not affect the overall Milanino mean body weight recorded in the straight-run group in the whole rearing period. However, the growth rate within sex was significantly different between the dietary treatments: heavier females were found in the HP group from 125 d onwards, while no differences were recorded in male body weights. The protein concentration of the diet did not affect carcass weight data or meat composition. The present results suggest the use of a low-protein diet for rearing straight-run Milanino chickens for long rearing periods. However, in females, a high-protein diet is recommended from 125 d of age onwards.
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15.
1. Body composition was determined in 9‐week‐old chickens sampled from four lines selected either for increased body‐weight gain (line W), for increased food consumption (line F), for decreased food conversion ratio (line E), or at random (line C), after three, four and five generations of selection. 2. After five generations of selection the proportions of carcass water (678 g/kg) and protein (187 g/kg) were highest in line E and lowest (636, 180 g/kg respectively) in line F. The proportion of fat was lowest (83 g/kg) in line E and highest (134 g/kg) in line F. 3. Lines W and C were similar and intermediate to lines E and F for all the carcass constituents. 4. There was more fat in females (115 vs 98 g/kg) and less protein (177 vs 190 g/kg) and water (652 vs 665 g/kg) than in males. 5. Line differences in carcass composition were not appreciably altered if birds were killed at equal weight rather than equal age. 相似文献
16.
This study evaluated the growth performance and meat characteristics of grower geese whose diets included garlic scape meal (GSM), a by-product of garlic production. Scape is the leaf-less flower stem of garlic. Garlic scape (GS) extracts contained 84.7 ± 3.8 μg/g dry weight (DW), 81.4 ± 8.2 μg/g DW, 0.78 ± 0.05 mg gallic acid equivalent/g DW and 31.67 ± 2.25 μg/g DW of allicin, alliin, total phenolics and flavonoid contents, respectively. In total, 120 White Roman geese aged 5 weeks were randomly distributed among 12 pens and fed on a grower diet ad libitum during the growth period. Employing a completely random design, 5 males and 5 females were placed in each pen. Each treatment was applied to three pens (in total 30 birds) and the treatments comprised the following: 1) control (maize–soybean meal), 2) 5% of maize replaced with 5% of GSM (5% GSM), 3) 10% of maize replaced with 10% of GSM (10% GSM) and 4) 15% of maize replaced with 15% of GSM (15% GSM). Each group of 30 birds was treated for 8 weeks. The results revealed that the 15% GSM group was characterised by a lower feed conversion ratio than the control group; however, these groups did not differ significantly in their body weights (BWs). In addition, the 10% GSM group did not differ in both the feed conversion ratio and consumption. The flavour intensity score of meats in the 10% GSM group was significantly lower than those of meats in the 5% GSM and control groups. The general acceptability scores of meats in the 5% GSM and control groups were higher than those of meat in the 10% GSM group. The study concluded that 5% dietary GSM in the feed did not adversely affect the growth performance, meat characteristics or sensory evaluation of grower geese. Hence, the environment can be protected by including agricultural waste in goose diets.
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17.
1. The objective of this study was to investigate differences in growth performance, serum intermediary metabolites, acute-phase proteins and white blood cells in low, medium and high–residual feed intake (RFI) chickens. It was also assessed if the environment affects the feed efficiency (FE) and FE-related performance and serum profiles of chickens.2. Individual body weight (BW) and feed intake (FI) were recorded from d 7 of life. At 5 weeks of age, female and male broiler chickens (Cobb 500) were selected according to their RFI (L1: Austria; L2: UK; n = 9/RFI group, sex and locatity -45on) and blood samples were collected.3. Chickens at L1 had similar FI but a 15% higher BW gain compared to chickens at L2. The RFI values of female chickens were ?231, 8 and 215 g and those of male chickens ?197, 0 and 267 g for low, medium and high RFI, respectively.4. Location affected serum glucose, urea, cholesterol, non-esterified fatty acids (NEFA) and ovotransferrin in females, and serum glucose and triglycerides in male chickens. Serum uric acid and NEFA linearly increased from low to high RFI in females, whereas in males, cholesterol showed the same linear response from low to high RFI. Serum alpha-1-acid glycoprotein and blood heterophil-to-lymphocyte ratio linearly increased by 35% and 68%, respectively, from low to high RFI but only in male chickens at L1.5. Regression analysis showed significant positive relationships between RFI and serum uric acid ( R2 = 0.49) and cholesterol ( R2 = 0.13).6. It was concluded that RFI-related variation in serum metabolites of chickens was largely similar for the two environments and that serum metabolite patterns could be used to predict RFI in chickens. 相似文献
18.
A study was conducted with breeding ostriches over two consecutive breeding seasons to determine their response to different concentrations of a well-balanced dietary protein. Five concentrations of protein were fed to both females and males at an intake of 2.5 kg/bird d. The respective diets contained 75, 91, 108, 123 and 140 g protein/kg feed with energy held constant at 9.2 MJ metabolisable energy/kg feed. Egg production (mean ± SE, 39.1 ± 3.6 eggs/female/season) was unaffected by dietary protein concentration. Similarly, no significant trends were found for the number of unfertilised eggs (9.1 ± 1.8), dead-in-shell chicks (8.2 ± 1.3), the number of chicks hatched (19.5 ± 2.5) and change in the mass of females (?16.3 ± 10.2 kg). Egg weight decreased linearly as dietary protein content increased. Age of the ostrich female had a highly significant effect on the number of eggs laid, the number of chicks hatched, the number of dead-in-shell and infertile eggs produced per hen, as well as the mass change of female breeding birds, but did not affect the response of any of these variables to dietary protein content. It was concluded that ostriches do not benefit from dietary protein contents greater than about 75 g/kg when this is fed at a daily total feed intake rate of 2.5 kg/bird during the breeding season.
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19.
Abstract Blood chemistry panels are commonly used for assessing the general health of vertebrate animals. Here, we present novel blood chemistry data for two North American sturgeon species, shovelnose sturgeon Scaphirhynchus platorynchus and lake sturgeon Acipenser fulvescens. Measurements were done using a portable chemistry analyzer (VetScan Analyzer; Abaxis). Among the plasma values measured (mean ± SD for shovelnose and lake sturgeon, respectively) were total proteins (3.7 ± 0.9 and 2.8 ± 0.4 g/dL), albumin (2.0 ± 0.5 and 1.1 ± 0.2 g/dL), globulin (1.7 ± 0.7 and 1.7 ± 0.3 g/dL), glucose (107 ± 46 and 62 ± 9.7 mg/dL), sodium (Na +; 132 ± 3.6 and 150 ± 14 mEq/L), potassium (K +; 3.5 ± 0.2 and 2.8 ± 1.7 mEq/L), phosphorus (10.4 ± 1.9 and 11.6 ± 3.6 mg/dL), and aspartate aminotransferase (AST; 676 ± 433 and 634 ± 234 IU/L). Higher values for total proteins, albumin, glucose, and Na + in shovelnose sturgeon than in lake sturgeon probably are the result of handling stress. In addition, the plasma of male shovelnose sturgeon had higher concentrations of AST, glucose, and globulin than did that of females, whereas the plasma of females had higher concentrations of albumin and K + than that of males. This study is the first to report blood chemistry data for shovelnose sturgeon. Robust blood chemistry databases can be used by aquaculturists and fish managers for monitoring sturgeon health. Received July 8, 2011; accepted February 2, 2012 相似文献
20.
1. Mass selection in two replicate lines of Leghorn chickens was practiced for low 20‐week body weight in males and by an index designed to reduce age at first egg, body weight at 20 weeks and maintain a constant early egg size in females. 2. Selection responses in body weights of hens at 40 and 60 weeks of age, as well as in average egg weight of all eggs, egg number, egg mass and feed conversion at the above ages are given for 5 generations of selection. 3. Estimation of genetic responses were made separately for selection on males (M i ) and females (F i ) using control groups of hens from matings between females with an index near the population average and either males with body weight near the population average (Cl) or the selected males within lines (C2). 4. Total genetic response to selection of both parents (CR i ) showed an expected decline in body weights of hens, small changes in egg weights and egg numbers, and an improved feed efficiency. 相似文献
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