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1.
2 rearing trials were carried out on a total of 8550 hybrid chicks (White Leghorn) to investigate in which way food mixtures containing reduced levels of crude protein (supplemented or unsupplemented with amino acids) might influence the growth of chicks and young hens. Decreases from 21.5% to 16.5% in the crude protein content of chicken feed and from 15% to 13% in feeds feed to young hens (greater than 8 weeks of life) did not reduce the live weight of birds at the end of the rearing period to any appreciable extent. No clearly defined differences were found to exist between the different types of feed tested concerning the amount of food and energy consumed per unit of weight gain and the mortality rate among the birds; it was shown, however, that the demand for crude protein per unit of weight gain was clearly reduced in birds reared at the lower crude protein level. For young hens receiving the diet poorer in protein the date when the birds began laying was slightly delayed. Otherwise, no statistically significant differences were found to exist between the young birds fed varying levels of crude protein, concerning the age at 50% laying performance and other parameters that are characteristic of the entire laying period (laying performance, weight of individual eggs, food consumption, mortality, fertilization of hatching eggs, hatchability of eggs). It appears that the feeding of a reduced protein diet to chicks and young hens (laying stock) did not have any detrimental effect on the growth and later laying performance of the birds. Apart from the fact that the demand for protein feeds is considerably reduced during the rearing period the costs of feeding per bird can also be cut down. 相似文献
2.
《The Journal of Applied Poultry Research》2010,19(1):1-12
This study evaluated the influence of inoculation of different nutrients into eggs of 18-d-old broiler embryos. On d 18 of incubation, before transferring, eggs were injected with a solution containing either maltose, a multivitamin supplement, zinc-glycine, glutamine, a mixture containing all these elements, or sodium chloride (control). After hatching, 2,400 male broiler chicks were placed in an experimental broiler house and distributed into 60 floor pens in a completely randomized design comprising a 2 × 6 factorial arrangement of treatments (2 egg weights × 6 solutions), for a total of 12 treatments. Birds and feed consumption were measured weekly. At 42 d of age, 3 birds per replicate pen were randomly selected for processing. Birds derived from heavier eggs had greater hatchability and hatching weight. At 42 d of age, birds from heavier eggs had higher BW, carcass weight, and breast meat weight. The livability of birds derived from heavy eggs was higher at 7 and 14 d of age. The in ovo inoculation of the nutrients to 18-d-old embryos did not influence live performance or carcass traits. The technique of in ovo inoculation of certain nutrients may be used in industrial poultry production, but further studies are required to define the best solutions or mixture of nutrients to be used. 相似文献
3.
A total of 84 farmers in 31 villages of Guadalcanal, Western, Malaita and Central Provinces of the Solomon Islands were surveyed
to obtain baseline information on the current feeding practices and farmer attitudes to village poultry production. Farming
of village chickens in the Solomon Islands is conducted on a small scale. Most surveyed farmers thought chickens were easy
to care for, provide food for the family and was a good cash income enterprise. Some farmers were interested in keeping local
chickens, but found it difficult to obtain the birds. The main feed sources are fresh coconut, copra meal, fish meal, mill
run, food scraps and forage sources from the range. Some villagers believe that chickens only need to eat household scraps
and did not provide drinking water. Many villagers lacked the knowledge of managing a village poultry enterprise. Some chicken
houses were built by using bush materials or by purchasing construction materials. Farmers indicated they would like the government
to provide funds for establishing a smallholder poultry enterprise and to provide information on feeding and management of
birds. 相似文献
4.
Kondombo SR Nianogo AJ Kwakkel RP Udo HM Slingerland M 《Tropical animal health and production》2003,35(6):563-574
This study aimed to describe and compare village chicken production in two farming systems in Burkina Faso. The systems were those in which crops and livestock production were, respectively, the most important. A rapid rural appraisal preceded a monitoring study in which data were collected fortnightly for 2 months. The study revealed that village chickens are used as sacrifices, gifts and objects of exchange for traditional medicine, or are sold for a little money under both systems. Chicken production is a free-range procedure in both farming systems, but there are differences in management. On average, the flock size was 33.5±3 birds, of which 57% were chicks. During the period of 2 months in the rainy season, the overall mortality was relatively low (8.8%±1.5) but mortality in chicks was high (31.7%). The main cause of financial loss in the village chickens was mortality, which represented up to 84% of the total exits. The hatching rate and mortality in young chicks differed significantly (p<0.05) between the two farming systems. 相似文献
5.
The National Animal Health Monitoring System (NAHMS) Small-Enterprise Chicken study was conducted to better understand bird movement and biosecurity practices of commercial poultry operations having fewer than 20,000 chickens. A stratified random sample of 2511 operations having 1000–19,999 chickens was selected from a list maintained by the National Agricultural Statistics Service (NASS), based primarily upon data from the 2002 Census of Agriculture; 1789 (72.1%) operations participated in the study. Over one-half of operations were contract operations with breeding birds, and one-fourth were contract operations without breeding birds. Only 17% of operations were independent (noncontract) operations. Independent operations were primarily table-egg producers and to a lesser extent, growers. Independent operations were more likely to have birds other than chickens, to allow outdoor access to birds, and had less stringent biosecurity requirements compared to contract operations. 相似文献
6.
Day-of-hatch broiler chicks housed in isolation units were each given, by oral gavage, 0.1 ml of Mucosal Starter Culture (MSC) or saline control. Each of the treated and control chicks was subsequently given a composite culture of three strains of bacitracin-resistant Clostridium perfringens (Cp) previously isolated from chickens with symptoms of necrotic enteritis. Some chicks were maintained on a corn-based diet provided ad libitum. Others were given the feed supplemented with 50% rye (a predisposing factor for necrotic enteritis). At 7, 14, and 21 days after receiving Cp, chicks were euthanatized, and cecal contents were diluted and plated on selective agar containing bacitracin. For chicks on corn feed, Cp numbers were similar in control birds and birds given MSC in three of four trials. In two of the trials that demonstrated no effect of MSC on Cp numbers, enterotoxin presence was determined. The number of birds with detectable Cp enterotoxin in their small intestine and the mean toxin levels were lower in the MSC-treated birds. In a fourth trial with birds on corn-based feed, mean Cp numbers and the number of Cp-positive birds were lower in the MSC-treated birds. For the two trials involving chickens on rye-supplemented feed, Cp numbers and the percentage of Cp-positive birds were significantly reduced in MSC-treated birds compared with control birds. Enterotoxin in birds receiving the 50% rye diet was at low levels or not detected in control and MSC-treated birds. Results suggest that MSC may reduce intestinal proliferation of Cp, a causative agent of necrotic enteritis in poultry and of foodborne disease in humans. 相似文献
7.
《The Journal of Applied Poultry Research》2009,18(2):355-366
Since the USDA implemented the National Organic Program, the growth of the organic food market has continued to increase, with organic poultry as leading products. Organic livestock husbandry practices focus on living conditions that permit natural behaviors and provide outdoor access, preventive health management with a prohibition of antibiotics or other drugs (although vaccines can be used), and organic feed. Organic feed is raised without synthetic fertilizers and pesticides; pastures to which birds have access must also be organic. Hatcheries are currently not required to be organic, and conventional chicks may be used if they are under organic management by the second day after hatching. Although alternative, slow-growing genotypes are used in organic production in the European Union, conventional genetics are used in the United States. Poultry products, including meat and eggs, must be handled organically. Most synthetic materials are not permitted in organic food production, whereas most natural materials are; however, the National Organic Program National List specifies which materials are allowed. Of particular interest is an impending ban on the use of synthetic methionine in organic poultry diets. Research in the United States has examined alternative strategies, including the use of slow-growing broilers that are less heavily muscled than conventional fast-growing meat birds, but has not shown these birds to have lower methionine requirements. Research has also examined sensory differences between specialty and conventional meat chickens in the United States. Consumer panelists indicated no preference between these products, although trained panelists found some differences in the flavor of thigh meat. More meat quality differences were due to genotype than to outdoor access. Breast meat from slow-growing birds was more tender than that from fast-growing birds. Outdoor access resulted in leaner meat, but only in the case of slow-growing birds. As interest grows in specialty and organic poultry meat products, additional research is needed. 相似文献
8.
MacLachlan DJ 《British poultry science》2008,49(3):290-298
1. Implementation of Good Manufacturing Practice and HACCP (Hazard Analysis Critical Control Points) in the production of poultry feed requires efficient tools for profiling risks associated with pesticide use in the production of crops for feed. 2. This paper describes a simple model that may be of use in the first tiers of risk profiling of feeds. 3. The model adequately reproduced the pattern of residues in fat and eggs of laying hens dosed with a selection of lipophilic pesticides that may be used in the production of crops for poultry feeds: deltamethrin, diflubenzuron, fipronil, lindane, piperonyl butoxide and spinosad. 4. Simulations suggest results derived from studies on laying chickens can be extrapolated to other laying birds. 5. Poultry meat production systems focus on maximising growth of birds giving rise to significant potential for dilution of residues that transfer to fat from feed. 6. Simulations of residues in fat of chickens, ducks, geese and turkeys exposed to a lipophilic pesticide with an elimination half-life of one day at 10 mg/kg body weight/d from hatching to typical market ages suggest residues in fat that are highest in turkeys > chickens > geese > ducks. 7. The model is of use in interpreting published dosing studies and predicting likely residues in birds at times after last exposure/dosing. 相似文献
9.
Gutierrez-Ruiz EJ Ramirez-Cruz GT Camara Gamboa EI Alexander DJ Gough RE 《Tropical animal health and production》2000,32(6):381-390
The commercial flocks in Yucatan, Mexico are free of Newcastle disease virus (NDV) in its velogenic viscerotropic form, but little is known about the disease status of backyard poultry. A seroprevalence survey in 30 villages using haemagglutination inhibition (HI) tests for infectious bronchitis virus (IBV) and NDV antibodies was carried out from December 1997 to June 1998. The seroprevalences were 56.5% (95% CI 50–63%) for IBV and 2.2% (95% CI 0.5–3.8%) for NDV. All the villages had chickens that were positive for antibodies to IBV and nine of the villages had chickens that were positive for antibodies to NDV. This suggests that IBV may be responsible for a large proportion of the respiratory disease observed in backyard chickens in Yucatan. The implications of these findings are discussed, including the highly susceptible status of the backyard chickens in Yucatan to NDV and the possibility of this virus being one cause of the syndrome known as mortandad by the local people. 相似文献
10.
Free-range Village Chickens on the Accra Plains, Ghana:Their Husbandry and Productivity 总被引：1，自引：1，他引：0
Aboe PA Boa-Amponsem K Okantah SA Butler EA Dorward PT Bryant MJ 《Tropical animal health and production》2006,38(3):235-248
A cross-sectional[4pc] survey investigating husbandry and productivity of free-range village chickens was carried out in four
administrative districts within 60km of Accra. Responses were provided by 101 men and 99 women. The mean (SD) household flock
size was 28.7 (25.97) and the median was 20. The factors included in the final model investigating variance in flock size
were sex of the respondent (p=0.011), administrative area (p=0.004), the numbers of members in the household (p=0.017) and the number of cattle, sheep and goats owned by the household (p=0.031). Chickens were owned by individual members of the household, but women and children were the predominant providers
of care for chickens. All respondents described their chickens as scavengers that were provided with supplementary feed, and
over 80% of respondents named maize as a supplementary food source. Approximately 50% of respondents claimed difficulty in
providing supplementary feed, with the degree of difficulty varying between administrative areas (p<0.001). A majority of respondents (approximately 65%) claimed that their chickens laid 3–4 clutches of eggs per year. Over
70% of respondents estimated that each clutch contained 10–20 eggs, and approximately 70% of respondents estimated that 75%
of the eggs hatched. Opinions on mortality varied, but 60% of men and 70% of women estimated that between 50% and 75% of both
chicks and adult birds died each year. Approximately 80% of respondents named Newcastle disease as the most important health
issue. The opportunities for and consequences of controlling Newcastle disease are discussed. 相似文献
11.
Production of quail-chick chimaeras by blastoderm cell transfer 总被引：2，自引：0，他引：2
1. Quail-chick chimaeras were produced by injecting dissociated quail blastoderm cells into chick embryos. 2. Quail blastoderms were removed from the yolk and the cells were dispersed by trypsin treatment or pipetting. The cell suspension (1 to 5 microliters) was injected into the subgerminal cavity of unincubated chick embryos. The chick embryos were then cultured in recipient eggshells. 3. Quail blastoderm cells injected into the chick embryos adhered to the chick embryonic cells. The rates of hatching were 8.6% (38 chicks from 441 eggs) and 40.3% (48 chicks from 119 eggs) when the volumes of the cell suspension injected were 3 to 5 microliters and 1 microliter, respectively. 4. Seven out of 86 hatched birds were clearly identified as being chimaeric because part of the feather colouring was of quail specificity. In addition to these chimaeric birds, there were 8 chimaeric embryos which died before hatching. The distribution patterns of the quail feathers were varied among the chimaeric birds and embryos. 5. This technique provides a basis for the investigation of chick embryo cryopreservation, genetic transformation and analysis of cell lineage of chickens. 相似文献
12.
13.
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
14.
The progress and transmission of blackhead disease in chickens was studied in battery cages and floor pens in the absence of vectors. Two-week-old chicks were inoculated intracloacally with Histomonas meleagridis and allowed to commingle with others in floor pens. There was no confirmed transmission of blackhead to other birds in the pen, whether stocked at 10% or 25% with infected birds. A second experiment evaluated the effects of feed restriction of chickens on spread of blackhead within floor pens. Inoculated seeder birds had severe cecal lesions of blackhead at necropsy, regardless of feed restriction. Uninoculated birds did not develop lesions by the time of necropsy at 42 days of age, regardless of whether full-fed or limited by skip-day feeding. Chickens inoculated intracloacally with H. meleagridis and placed in battery cages became infected and had cecal lesions of blackhead, but few liver lesions. Chickens allowed to commingle with the inoculated birds in batteries had no lesions of histomoniasis at necropsy 2 wk postinoculation. Coccidial oocysts from turkeys (Eimeria adenoeides) were inoculated along with H. meleagridis from cultures to test the effects of sporozoite penetration in the ceca on progress of blackhead disease. Histomoniasis was not worsened by the interaction with sporozoites, as shown by unchanged severity of cecal lesions, the number of birds showing liver lesions, or the overall number of positive birds. Overall, blackhead infections showed no inclination to spread from bird to bird under conditions of these studies, in contrast to what has been reported for turkeys. These results suggest that the dynamics of blackhead transmission in chickens differs significantly from that of turkeys, where transmission from bird to bird is rapid and effective in the absence of vectors. 相似文献
15.
16.
Distribution of maternally transmitted Salmonella antibodies and their protective effects were studied in the progeny of broiler breeder birds which had been vaccinated with live S. Typhimurium and inactivated S. Enteritidis vaccines. Vaccination resulted in a significant increase of the antibody concentration in yolk of hatching eggs and in serum and jejunum of the progeny of immunized breeder birds. Higher antibody titres for isotypes IgG and IgA were still seen on day 21 of age. Antibody production of isotypes IgA and IgM by the chickens themselves was found between 14 and 21 days of age. Two challenge models (10(2) cfu/bird on day 1 of age and a seeder bird model, respectively) were used to evaluate the efficacy of maternal antibodies against challenge with S. Enteritidis. Using both models numbers of challenge organisms were lower in the caeca of the progeny of immunized parent birds between day 7 and day 21 of age (maximum about 1.5 log10 units) compared with control chicks. The results indicate the efficacy of maternally transferred antibodies but it remains the question of their practical relevance. The effects of acquired maternal antibodies on an active immunization of the progeny of immunized breeder birds with live Salmonella vaccines are discussed. 相似文献
17.
Village chickens are an important livestock for many rural families in Myanmar and other developing countries. Village chickens are kept under free-ranging conditions, with confinement only at night. Therefore, it is likely that some deaths are not observed by farmers. We conducted a longitudinal study from November 2003 until May 2004 to describe temporal patterns of mortality of village chickens in 10 villages in Myanmar. Field veterinarians first identified the numbers of birds in all chicken-owning households in each village. We then selected 307 households randomly with stratification by flock size. Each study household was then visited once monthly at which time questionnaires were completed recording current flock structure and numbers of hatchings, mortalities, sales and birds consumed since the previous visit. In addition, sera were collected from a sample of adult birds and growers. Depending on month and age group of chicken, from 71 to 231 (out of 290-307) households had discrepancies in the counts of birds. For chicks, at least one-quarter of the households had unobserved losses of at least 5 chicks per household (maximum 66 chicks); unobserved losses were less for growers and adult chickens. The median month-specific, village-specific mortality rates per 1000 bird-days at risk (counting missing birds as deaths) ranged from 0.8 to 1.7 for adults, from 0.4 to 4.7 for growers and from 8.0 to 16.5 for chicks. Across all birds, the prevalence of protective titres against Newcastle disease virus was 79% (95% confidence interval 74, 84); higher prevalences of protective titres were associated with reduced mortality rates in the following months. 相似文献
18.
黑鹳在人工饲养条件下的繁殖 总被引：2，自引：0，他引：2
１９８５年－１９９３年对黑鹳先后组成４对配偶，共产卵３２枚，受精卵１４枚，受精率４３．７５％，出雏８只，出雏率５７．４％，成活５只，成活率６２．５％。黑雏在笼养条件下，３岁龄性成熟。齐齐哈尔地区４－６月份产卵，一般窝产卵４枚，年最多产卵１６枚，孵化期３１天。黑鹳为晚成鸟。自然育雏在雏鸟出壳后３－４小时开食，人工育雏２４小时开食，１５日龄雏鸟开始生长初级飞羽羽鞘，２０－２５日龄能站立，３０－３５日龄 相似文献
19.
Jang SI Jun MH Lillehoj HS Dalloul RA Kong IK Kim S Min W 《Veterinary parasitology》2007,144(1-2):172-175
Anticoccidial effects of green tea (GT)-based diets were evaluated in chickens following oral infection with Eimeria maxima an ubiquitous intestinal parasite of poultry that impairs the growth and feed efficiency of infected birds. Five-week-old chickens were assigned to four groups (GT 0.5%, GT 2.0%, untreated/infected and non-infected control) and each group consisted of 15 chickens. Chickens were fed a standard diet supplemented with ground green tea for 2 weeks prior to infection with E. maxima (10,000 sporulated oocysts per bird). The effects of green tea on E. maxima infection were assessed by two parameters, fecal oocyst shedding and body weight gain. The green tea-fed chickens produced significantly reduced fecal oocysts (P<0.05) when compared to the E. maxima-infected group fed standard diet. The green tea-based diet, however, did not improve body weight loss caused by E. maxima infection. This study is the first to demonstrate anticoccidial effect of green tea on Eimeria parasites. 相似文献
20.
Waldenstedt L Elwinger K Lundén A Thebo P Bedford MR Uggla A 《British poultry science》2000,41(4):459-464
1. The effect of intestinal digesta viscosity on bird performance in chickens with coccidiosis was compared to those without coccidiosis. 2. Six hundred chicks were divided into five groups: one control group was fed a basal maize/soyabean-based diet and the other groups were fed the basal diet supplemented with 2, 4, 6 or 8 g carboxymethyl cellulose (CMC) per kg of feed. At 14 d of age half the birds were individually inoculated with sporulated oocysts of Eimeria acervulina and Eimeria praecox. 3. Intestinal digesta viscosity increased with increasing inclusion of CMC. This effect was considerably less pronounced in inoculated than in non-inoculated birds. 4. There was a significant negative effect on live weight gain and feed conversion ratio (FCR) with increasing CMC inclusion in non-inoculated birds, but in inoculated birds there was no clear relation between CMC inclusion and performance. Neither intestinal lesion scores, nor numbers of Clostridium pefringens in the caeca, were significantly affected by CMC inclusion. 5. Across all diets inoculation impaired growth rate by 9% and FCR by 8%, but did not affect the amount of C. perfringens in the caeca. 相似文献