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1.
1. In experiment 1, 10 laying hens were given the choice to eat food pellets from any of 4 food bowls illuminated by overhead, incandescent luminaires at <1, 6, 20 or 200 lux. During a trial hens were allowed to eat for 5 min. After each minute had elapsed (from the start of eating) the light sources were extinguished and the illuminances re-assigned to the food bowls in a random manner. Each hen received two trials, one where the food was freely available and another where it was hidden in a sand and gravel mix. 2. The hens chose to eat for most time in the brightest (200 lux) and least in the dimmest (<1 lux) environments for both free and hidden food (free: 5.9, 10.5, 10.4, 15.7s for increasing illuminance; Hidden: 5.5, 9.8, 9.1 and 15.7s. 3. In experiment 2, 9 hens were trained to peck at either an illuminated or unilluminated panel to access a food reward behind a guillotine door for 3 s. Five hens were trained to peck the illuminated panel to access food brightly lit (200 lux) or the unilluminated panel to access food dimly lit (<1 lux); 4 hens were trained vice versa. The flock was then divided into three groups of three, and three treatments imposed on each group in a Latin-square arrangement. In treatment 1, one peck at either panel allowed access to the chosen light environment (F1:F1). In treatment 2, 5 pecks were required to access food brightly lit on a variable ratio, but only one to access food dimly lit (ratio V5:F1). In treatment 3, the variable ratio was increased to V10:F1 to access food in the light. 4. Over 40 trials for each hen, the mean number of attempts to eat food in the light (where the panel which allowed access to food brightly lit was pecked at least once) was 34.5 for F1:F1, 12.1 for V5:F1 and 8.5 for V10:F1. The mean number of food rewards taken in bright light was 34.5, 3.1 and 1.8, respectively. For both variables, the difference between F1:F1 and V5:F1 was significant but not between V5:F1 and V10:F1. By interpolation of the 'attempts' data, it was estimated that hens would work 2.3 times harder to gain access to food brightly lit than for food dimly lit. 5. In experiment 3, the influence of the same illuminances applied over a food bowl as in experiment 1 (<1, 6, 20 or 200 lux) on the number of pecks/min, food consumed/min, food consumed/peck and the force of pecks was examined. 6. The amount of food consumed was lowest in the dimmest environment (3.1 vs 7.5, 7.4 and 7.1 g/ min for increasing illuminance, respectively); as was the number of pecks (35.6 vs. 125.0, 123.1, and 125.4 pecks/min respectively for increasing illuminance). The amount consumed per peck did not vary significantly with illuminance. The mean peck force showed a trend to be lowest in the dimmest environment (5.3 vs. 6.6, 7.0 and 6.6 N respectively, for increasing illuminance). 7. Overall, the hens showed a preference and appeared motivated to eat in bright as opposed to dim light. The hens were unwilling to eat at low illuminances although the 'efficiency' of eating (g/peck) was not impaired significantly. These data may have implications for novel lighting systems and those where hens are required to eat in the dark or in very dim light. 相似文献
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1. Age-related changes in egg production, oviposition sequence length and inter-sequence pause length were studied by analysis of oviposition records of 50 individually-caged broiler breeders from 24 to 62 weeks of age. 2. The 44 surviving hens exhibited a production profile characteristic of broiler breeders (184 eggs per hen), with a peak mean sequence length of 19 eggs at 32 weeks of age. Inter-sequence pause length was maximum (1.6 d) at 54 weeks of age. Overall, the hens averaged 48 sequences, with a mean sequence length of 4.1 d. 3. Most hens had a single characteristically long sequence about the time of peak egg production (average: 24.3 d). The term 'prime' is suggested to denote this sequence. 4. Sorting the hens into groups on the basis of total egg output (upper and lower 50% and upper and lower 25%) indicated that high producing hens (upper 50% and 25%) had a very long prime sequence early in lay, and had few inter-sequence pauses of greater than 1 d duration. The converse was true for low producers (lower 50% and 25%). 5. The length of the prime sequence may be a good indicator of reproductive efficiency of hens later in life. 相似文献
3.
1. Commercial broiler breeder hens lay many eggs on the floor rather than in nest boxes provided. A study was conducted to determine whether feeding feed-restricted broiler breeder hens during the sitting phase of nesting results in a higher incidence of floor eggs and/or retained eggs. 2. Sixty broiler breeder females (Ross 308) were randomly assigned to 6 deep litter pens containing 10 nest-boxes. At 35 weeks of age and for 9 weeks, feed was distributed to all pens at lights-on every second day (fed normally, FN). On alternate days (feeding delay, FD), feed was distributed when 2-3 hens/pen were sitting in a nest box. Behaviour was sampled at 41 weeks of age, for 26 d. Eggs and egg location data were collected daily, and eggs were scored for extra-cuticular calcium. 3. Of 81 instances in which the hen was sitting firmly in a nest box at the time of feeding, on 80 instances the hen left the nest-box to feed, and on one instance the hen laid her egg then exited to the feeder. Of these 80 instances, on 58 occasions the hen returned to a nest-box to lay her egg; on 12 the hen returned to the nest-box but laid no egg; on 7 the hen did not return to the nest box and laid no egg; and on three the hen laid her egg on the floor. 4. Mean floor egg percentage was 13·3 ± 3·2% on FN and 13·3 ± 4·7% on FD days; these did not differ significantly. 5. The mean extra-cuticular calcium score over all pens was 0·9 ± 0·06 on FN days and 1·2 ± 0·06 on FD days; these differed significantly. 6. In conclusion, feeding broiler breeder hens during nesting results in a conflict between feeding and nesting motivation and higher numbers of extraneously calcified eggs, but does not result in a significant increase in floor eggs even though nesting hens will leave the nest box for food. 相似文献
4.
After N-balance experiments with broiler hens in the top laying period and the feeding of soybean coarse meal/fish meal protein the protein utilisation values were calculated. The PNu curve and the PEW curve could be described as utilisation values from the N-retention curve (e-function). At an intake of N at which the hen neither decomposed nor retained protein, the utilisation (PNu) for maintenance and egg production was 55.3% and the utilisation of feed protein for egg production 49.4%. Maximum PEW 34.3% could only be ascertained at an N-intake/LW0.67kg of 1500 mg. The corresponding crude protein quota of 18.7 g recommended as crude protein requirement is calculated from this N-quota (xm) and a live weight of the broiler hen of 2804 g. For the same N-quota (xm) and the same live weight of the hens this results in a necessary quota of S-AA of 694 mg per hen and day. Provided the daily feed intake is 145 g and thus the intake of crude protein 18.7 g and that of S-AA 694 mg per hen, the necessary crude protein content of the feed is 130 g per kg original substance and an S-AA concentration which is equivalent to 3.7% of the crude protein (in g/16 g N). 相似文献
5.
本试验旨在探索添加大豆黄酮后对肉种鸡产蛋和繁殖性能的影响。选取43周龄体况接近一致(体重、产蛋率)的肉种鸡S2系母鸡240只,随机分成4组,每组6个重复,每个重复10只:选取1组作为对照组,饲喂无大豆黄酮的基础饲粮,其余3组分别在基础饲粮基础上添加5、10、20 mg/kg大豆黄酮。再挑选20只强健的S2系公鸡采集精液,混精对试验鸡进行人工授精,试验期为15周。结果表明:与对照组相比,1)添加大豆黄酮对S2系母鸡体增重、采食量及死亡率无显著影响(P0.05)。2)添加大豆黄酮后能显著提高产蛋率(P0.05),其中10 mg/kg组产蛋率提高了4.1%(P0.05),日产蛋量提高了3.5%(P0.05),为3组最佳。5、10 mg/kg组料蛋比分别降低了8.0%和11.2%(P0.05)。3)10 mg/kg组受精率、孵化率和健雏率分别提高了13.1%、20.5%和5.8%(P0.05)。由此可见,饲粮中添加大豆黄酮能显著影响肉种鸡产蛋和繁殖性能,其中10 mg/kg组综合效果最佳。 相似文献
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7.
In the top laying period (29th/30th week of life) egg protein synthesis and protein retention in the bodies of laying hens were ascertained. Based on egg-N analyses, the relation between N-intake/live weight0.67kg and egg-N discharge/kg LW0.67kg was regressively calculated and described. The subtraction of egg-N discharge/LW0.67kg from N-balance/LW0.67kg made it possible to estimate N-retention/LW0.67kg in the body. From the intersection of this curve with the chi-axis it follows that the broiler hen meets the N-requirement for maintenance and egg production with a daily consumption of 1,264.7 mg N/LW0.67kg, which corresponds to 15.8 g crude protein, and then neither loses nor retains body protein. At a daily intake of this amount of CP (15.8 g) the broiler hen produces 44.1 g egg per day. An energy intake of more than 70 EFUhen/animal and day resulted in fat retention in the broiler hen. 相似文献
8.
Dietary phosphorus and food allowance of dwarf breeders affect reproductive performance of hens and bone development of their progeny. 总被引：1，自引：0，他引：1
1. An experiment was conducted with 144 caged hens to study the effects of different dietary concentrations of phosphorus and of food restriction on the reproductive performance of dwarf breeder hens and on the growth and the bone development of their progeny. 2. Severe food restrictions at 105 g/hen day compared to 115 g/hen day, decreased hen body weight and hen day egg production. Fertility was unaffected and hatchability slightly depressed by the more severe restriction. 3. Egg and one-day-old chick weights were decreased by limiting the food intake of the breeders but the negative effect disappeared at slaughter (7 weeks). 4. Shell quality decreased as the dietary phosphorus increased and was not affected by food allowance. Albumen quality was slightly impaired in severely restricted hens. 5. Serum inorganic phosphorus in hens and yolk phosphorus increased with increasing dietary phosphorus. Tibial breaking strength and tibial percentage ash of the progeny at hatching was markedly improved in proportion to maternal phosphorus and food intake. This improvement in bone quality was not maintained at 7 weeks. 6. The number of chicks affected by twisted legs (valgus) and dyschondroplasia were similar whatever the maternal diet. The frequency of valgus was higher in males than in females. 7. It is concluded that maternal food intake and phosphorus supply are of importance for the initial bone development of the progeny. 相似文献
9.
Khaled Abouelezz Fouad Mohammed Luis Sarmiento-Franco Ronald Santos-Ricalde Javier Francisco Solorio-Sanchez 《Tropical animal health and production》2013,45(2):367-372
The aim of this experiment was to study the suitability of the outdoor system for Rhode Island Red hens under the tropical conditions of southern Mexico. Twelve floor pens, each containing four birds, were divided randomly into two groups. The first group was raised indoors only, while each of the second group replicates had access to an outdoor area with natural-grown vegetation from 0800 to 1700 hours daily. Both groups fed ad libitum on a commercial layers diet. The results revealed no differences in body weight between treatments. The outdoor group recorded significantly higher egg laying rate (86.90 vs. 78.05 %), higher egg mass (50.66 vs. 45.30 g egg/hen/day), and higher feed intake (103.70 vs. 97.67 g/day) versus the indoor group. The outdoor group had eggs with darker yellow yolks (9.46 vs. 5.46), lower yolk, and higher albumen proportions (P?<?0.05) versus the indoor group. The crop content of the outdoor hens consisted of 86.55 % concentrated feed, 6.30 % plant material, 2.27 % grit stones, 1.69 % snails and oyster shells, 1.25 % seeds, 0.95 % farm wastes, and 0.99 % insects, worms, and larvae. Of the outdoor hens, 43.1 % was observed to be in the range at each scanning time. The outdoor system in the tropics had beneficial effects on Rhode Island Red hen performance, and the hens utilized the outdoor area effectively and obtained various feed items. 相似文献
10.
Heck A Onagbesan O Tona K Metayer S Putterflam J Jego Y Trevidy JJ Decuypere E Williams J Picard M Bruggeman V 《British poultry science》2004,45(5):695-703
(1) Tolerance to ad libitum feeding was compared in three genotypes of broiler breeder hens: a standard broiler breeder fed ad libitum (SA) or restricted (SR), a slow growing 'label' broiler breeder (L) and an experimental dwarf heavy broiler breeder (E). Two similar experiments were conducted in two distinct research centres. (2) Feed intake and body weight were measured every 3 weeks from hatch to 40 to 49 weeks of age. Egg production and egg abnormalities were recorded. The number of yellow follicles in ovaries was counted at the age of 32 weeks. (3) Body weight was stabilised at 2.2, 3.7 and 5.4 kg after 24 weeks of age in L, E and SA hens, respectively. Growth of the SR hens was similar to that of L up to 20 weeks and stabilised at a similar level to that of E hens after 30 weeks of age. (4) Sexual maturity was delayed by 6 weeks in restricted breeders compared to ad libitum fed hens that started to lay at 20 weeks. SA hens had low egg production and a high proportion of defective eggs, which was largely compensated for by feed restriction. However, productivity of SR hens remained lower than that of L breeders. (5) Compared to the low viability and reproductive fitness observed with SA hens, the E dwarf broiler breeder tolerated ad libitum feeding and had better egg production, fewer egg abnormalities and yellow follicles per ovary and a higher egg production. However, laying rate was still lower than that of the SR and L groups. Energy conversion (kJ/g egg) from 32 to 40 weeks of age was much higher in the SA group than in the other three groups. 6. The feasibility of feeding a dwarf broiler breeder ad libitum calls for further research on implications of specific IGF and GH-receptor expression at the level of the ovary in dw chickens. 相似文献
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12.
Owoade AA Oluwayelu DO Fagbohun OA Ammerlaan W Mulders MN Muller CP 《Avian diseases》2004,48(1):202-205
Sera samples from seven poultry farms in southwest Nigeria consisting of 7 broiler, 10 pullet, 1 layer, 1 cockerel, and 1 broiler breeder flocks were tested for the presence of chicken infectious anemia virus (CIAV) antibodies using a commercial enzyme-linked immunosorbent assay kit. Eleven of the 20 flocks (55%) and six out of seven (86%) farms were positive for CIAV antibodies. The seroprevalence largely depended on the age of the flocks. Seroprevalence was higher within the older pullet and layer flocks (83%-100%) than in the younger broiler flocks (0%-83%). In essence, all flocks older than 6 to 8 wk became infected. This is the first report of serologic evidence of CIAV in Subsaharan Africa. Since Southwest Nigeria is the main port of entry of imported chicken and the hub of major poultry breeders, the disease can probably be found throughout the country and beyond. Further studies are necessary to assess economic losses due to CIAV and the cost benefit of countermeasures. 相似文献
13.
在青海省海东地区某部队养鸡场观测黄金褐商品蛋鸡的生产性能，并总结其饲养管理。结果表明雏鸡成活率为98.95%，育成期成活率为96.95%，产蛋期成活率为95.15%，饲养日增产蛋率79.1%，平均最高峰产蛋率92%，平均蛋重61.5g。该品种比较适应青海高海拔、寒冷的地理环境，且有推广价值。 相似文献
14.
Bisschop SP van Vuuren M Gummow B 《Journal of the South African Veterinary Association》2004,75(3):125-128
Ornithobacterium rhinotracheale (ORT) is a recently identified bacterial pathogen of poultry, linked to the respiratory disease complex of broilers and the economic losses associated with that disease complex. Present control measures applied for the disease include the continuous use of in-feed antibiotics. A recently developed bacterin vaccine that is applied to broiler-breeder hens to pass on protective immunity to their broiler progeny was tested under large-scale commercial conditions in South Africa. An indirect ELISA test for antibodies to ORT, optimised for use in South Africa, was used to determine antibody levels in breeders and broilers. ELISA test results showed that the vaccine stimulated the development of high antibody titre levels in broiler breeders. The efficacy of the vaccine in protecting the progeny of these birds from ORT challenge could not be determined during the trial, although the progeny of vaccinated hens appeared to perform slightly better under commercial conditions than the progeny of unvaccinated hens. 相似文献
15.
An infectious bursal disease vaccine, registered for use in breeder flocks, was studied for efficacy on the day-old offspring of vaccinated hens and for virulence in susceptible day-old and 6-week-old chickens. When given to susceptible day-old chicks and 6-week-old cockerels, the vaccine was found to induce atrophy and pathology of the bursa of Fabricius similar to that observed in field infections. Chicks vaccinated at day-old had markedly lowered titres in the haemagglutination inhibition test to Newcastle disease virus, when this was given 2 weeks later, but the response of the 6-week-old cockerel was similar to that of control birds. Maternal antibody induced by the vaccine protected chicks against infection at day-old. 相似文献
16.
The possibility that egg production in broiler breeder hens may be increased by selection for reduced oviposition interval under continuous light was investigated by comparing the pattern of pre-ovulatory releases of plasma luteinising hormone (LH) and the associated ovipositions in the same broiler hens maintained under normal cycles (15.25 h light/d) or continuous light. The lighting conditions had no effect on plasma concentrations of LH before and at the pre-ovulatory LH peak in first, mid-sequence or terminal ovulatory cycles. Plasma LH concentrations were similar during first, mid-sequence and terminal ovulatory cycles. Mid-sequence oviposition intervals and the interval between a mid-sequence LH peak and its associated oviposition were longer under continuous light than under normal lighting. Pre-ovulatory releases of LH occurred during a restricted period of day in both lighting conditions. Under continuous lighting they were probably entrained by the daily pattern of restricted feeding. Any selection programme for reduced oviposition interval under continuous lighting in broiler breeder hens should take into account the entraining effects of the daily pattern of feeding. 相似文献
17.
《The Journal of Applied Poultry Research》2004,13(4):533-539
A study was conducted to examine the effect of yeast culture residue (YCR) on the suppression of aflatoxicosis in broiler breeder hens. One hundred twenty, 35-wk-old, Cobb broiler breeder hens of the same cross were fed diets supplemented with aflatoxin (AF) (0 or 3 mg/kg) and YCR (0 or 2 lb/ton) singly and combined in a 2 × 2 factorial designed experiment. The birds were randomly assigned to pens with 3 replicates of 10 females and 1 male per treatment. Eggs laid by the hens were collected daily, stored at room temperature, and incubated every 7 d for 3 wk. Response variables analyzed were mean percentage of fertility, hatchability, hen-day egg production, egg weight, chick weight at hatch, and embryonic mortality over the 3-wk treatment period. At the end of 3-wk treatment, blood was collected from the hens and analyzed for total protein, globulin, and albumin. Aflatoxin did not negatively affect fertility. However, hen-day egg production (57.6%), percentage of hatchability (67.6%), embryonic mortality (24%), serum total protein, globulin, and albumin were significantly (P < 0.05) affected by AF. Hatch of fertile eggs from the AF-fed hens was significantly lower than the control (67.6 vs. 78.5%). The inclusion of YCR in the AF-treated diet raised the level of hatchability (74.9 vs. 67.6%), egg production (65.83 vs. 57.26%), and lowered embryonic mortality (16.8 vs. 24%). Serum globulin and albumin were lowered in the AF-fed hens but was partially restored with the addition of YCR. The data demonstrated that YCR may enhance the performance of broiler breeder hens that are provided feed contaminated with AF. 相似文献
18.
Effects of food intake regulation on the energy metabolism of hens and cockerels of a layer strain 总被引：1，自引：0，他引：1
1. Indirect calorimetry was used to study the effects on the energy metabolism of cockerels and hens after peak lay of a hybrid layer strain of regulating food or energy intake to 80% of ad libitum for an extended period of time. 2. Regulation of food intake decreased fasting and fed heat productions per bird and per unit metabolic body weight (kg0.75). 3. Maintenance energy requirements (per kg0.75) of both sexes were reduced about 20% by regulation; maintenance requirements of cockerels were about 30% lower per kg0.75 than hens on the same treatments. 4. Reducing the intake of all nutrients by 20% had the same effect on the energy metabolism of cockerels as restricting energy alone by the same amount. 5. Gross efficiency of egg production, in terms of both mass and energy, was higher when intake was regulated. During weeks 21 to 52 of restriction, daily egg mass output was significantly higher in hens fed ad libitum. 6. After 52 weeks of food regulation, restricted hens weighed 20% less and their total carcass energy was 36% less than hens fed ad libitum; similar effects were found in the cockerels. 相似文献
19.
The crop immune response against Salmonella Enteritidis (SE) challenge in eight commercial egg-layer strains (five white-egg layer and three brown-egg layer) and specific-pathogen-free (SPF) White Leghorn (WL) hens was investigated. Pre- and post-SE challenge mucosal immune responses within the crops were evaluated. Commercial layers and SPF WL hens were orally challenged with 10(8) CFU/ml SE PT13a and SE nalR PT13, respectively. Crop lavage samples were collected at weekly intervals from day 0 (pre-challenge) to day 25-27 postinfection (PI), and bacteriological examination was performed to monitor progression of SE infection. Crop lavage samples were analyzed for SE-lipopolysaccharide (LPS)-specific IgA using enzyme-linked immunosorbent assay (ELISA). H&E-stained slides of crop sections from day 34 PI and uninfected controls were assessed for lymphoid tissue via light microscopy. Lymphoid areas were graded based on morphology, size, and cellularity using a score 0 to 5 scale. The 0 to 5 (low to high) numerical values represented progressive increases in size and cellular density of lymphoid tissue. Bacterial culture results showed the highest percentage of SE-positive crop lavage samples from all hen groups at day 5-6 PI and day 11-12 PI. A progressive decline in percentage of SE-positive crop lavage samples did occur as time PI lengthened; however, at day 25-27 PI SE persisted in crop lavage samples from SPF WL hens and three commercial white-egg layer strains. A marked increase in SE-LPS-specific IgA was measured in crop lavage samples between day 0 and day 11-12 PI for all hen groups. Crop SE-LPS-specific IgA response remained elevated above day 0 baseline for the duration of the experiment. Well-defined score 3 to 5 lymphoid tissue aggregates were observed in crop tissue sections harvested at day 34 PI. Comparison of crop sections determined a 1.2-4.0 times increase in ratio of lymphoid tissue in day 34 PI SE-challenged hens vs. uninfected control hens. 相似文献
20.
饲粮添加维生素E和酵母硒对黄羽肉种鸡产蛋性能、孵化性能及蛋中维生素E和硒沉积量的影响 总被引：1，自引：0，他引：1
本试验旨在研究饲粮添加维生素E和酵母硒对黄羽肉种鸡产蛋性能、孵化性能及蛋中维生素E和硒(Se)沉积量的影响。试验采用3×3双因子设计,设3个维生素E添加水平(0、20、40 IU/kg)和3个Se添加水平(0、0.15、0.30 mg/kg)。选用32周龄快大型岭南黄羽肉鸡父母代种母鸡864只,根据产蛋率和体重一致性原则随机分成9个组,分别为VE_0Se_0组、VE_0Se_(0.15)组、VE_0Se_(0.30)组、VE_(20)Se_0组、VE_(20)Se_(0.15)组、VE_(20)Se_(0.30)组、VE_(40)Se_0组、VE_(40)Se_0.15组和VE_(40)Se_0.30组,每组6个重复,每个重复16只鸡。试验期8周。结果表明:1)饲粮中维生素E和Se添加水平对黄羽肉种鸡的体增重、平均日产蛋量、料蛋比、平均蛋重、产蛋率、破蛋率和不合格蛋率均无显著影响(P0.05)。2)饲粮中维生素E和Se添加水平对黄羽肉种鸡的蛋长径、蛋短径、蛋白高度、蛋黄颜色、哈氏单位、蛋黄重、蛋壳重和蛋壳厚度均无显著影响(P0.05)。3)饲粮中维生素E和Se添加水平对黄羽肉种鸡的健雏出壳重、孵化率、弱雏率和受精率均无显著影响(P0.05)。4)饲粮中维生素E添加水平对黄羽肉种鸡血浆MDA含量有显著影响(P0.05),随饲粮中维生素E添加水平的升高血浆MDA含量呈降低趋势,其中维生素E添加水平为40 IU/kg时血浆MDA含量显著低于0 IU/kg时(P0.05);饲粮中维生素E和Se添加水平对血浆MDA含量有显著交互作用(P0.05),其中VE_(40)Se_0组的血浆MDA含量显著低于VE_0Se_(0.15)和VE_0Se_(0.30)组(P0.05)。5)随饲粮中维生素E和Se添加水平的升高,黄羽肉种鸡蛋中维生素E和Se含量显著增加(P0.05);饲粮中维生素E和Se添加水平对蛋中维生素E和Se含量有显著交互作用(P0.05)。结果提示,维生素E可以提高黄羽肉种鸡的抗氧化水平,饲粮中维生素E和Se添加水平可以显著影响蛋中维生素E和Se的含量;建议在无任何应激因素刺激和不使用Se缺乏地区饲料原料的情况下,黄羽肉种鸡玉米-豆粕型饲粮可以不用额外添加维生素E和Se。 相似文献