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1.
1. The effect of replacing dietary cholecalciferol (D3) by 1 alpha,25-dihydroxycholecalciferol (1,25-(OH)2D3) on egg shell quality and egg production was tested on 32-week-old White Leghorn laying hens over 9 weeks. 2. Hens fed on a diet supplemented with 5 micrograms 1,25-(OH)2D3/kg diet, tended to lay more eggs, and the eggs had significantly higher specific gravity and percentage shell than eggs from control hens fed on a diet supplemented with 27.5 micrograms D3/kg diet. 3. The effect became apparent after about 4 weeks of treatment and persisted until the end of the test. 4. Hens fed on a diet without D3 supplement started to lay very thin or soft shelled eggs within 4 weeks, suggesting that the birds' reserves of D3 or its metabolites were depleted within this period. 5. The results suggest that 1,25-(OH)2D3 can be substituted for D3 in layer diets to improve egg shell quality. 相似文献
2.
In 29 domestic hens, four blood samples were collected during the period of egg formation, at time points representing different metabolic stages. Plasma concentrations of total calcium, total phosphorus, inorganic phosphorus and total protein were measured, and the effect of adding oyster shell particles to a standard laying diet was investigated. Analyses of covariance were made and correlations between the plasma characteristics were calculated. The following were significantly correlated: total and inorganic phosphorus, calcium and total phosphorus, and calcium and protein. Each of the four characteristics showed a significant decrease during egg formation. Inorganic phosphorus reached a peak 15 h after ovulation, probably related to medullary bone resorption. Plasma total phosphorus differed significantly between chickens. Addition of oyster shell to the diet did not affect the concentration or the pattern of the plasma characteristics during egg formation and did not reduce calcium mobilisation from medullary bone during shell formation. 相似文献
3.
Mrljak V Grabarević Z Dzaja P Barić Rafaj R Perić J Artuković B Bidin Z Kis S Stavljenić Rukavina A Serman V 《British poultry science》1999,40(4):523-528
Five groups of laying hens were treated with different gizzerosine doses (0, 2.5; 5.0; 7.5; 10.0 mg/kg/body weight of gizzerosine) daily over a 21-day period to determine the serum concentrations of 1.25-dihydroxycholecalciferol (1,25(OH)2D), total calcium, inorganic phosphorus and magnesium. Blood samples were taken on days 7, 14, and 21 of the experiment. The concentration of 1,25(OH)2D remained unchanged after day 7 in the gizzerosine-treated birds compared to the control group. After 14 days, it was significantly lower in the birds receiving. gizzerosine, compared with the control group. On day 21, 1,25(OH2)D concentrations were also significantly decreased in all 4 gizzerosine-treated groups compared with the control hens. The serum total calcium, inorganic phosphorus and total magnesium concentrations varied significantly, but irregularly, during the period of the study. 相似文献
4.
1. In 2 experiments the effects of dietary phosphorus on relationships between plasma inorganic phosphorus concentration (Pi), shell and egg production and depletion states were measured in brown laying hens. 2. In a 12-week experiment dietary phosphorus concentrations from conventionally deficient (1.6 g non-phytate-phosphorus (PNP)/kg) to moderate excess (3.9 g PNP/kg) had little effect on egg and shell production, although there was evidence that plasma Pi concentration, when not influenced strongly by shell formation, reflected dietary phosphorus content. 3. Among birds at each dietary phosphorus concentration there was a negative linear relationship between shell weight of early eggs in the sequence and plasma Pi concentration. The relationship was apparently not affected by dietary phosphorus concentration. 4. Continued feeding of the deficient diet to 61 weeks of age did not have effects on body weight, egg and shell production, other than those associated with age, but plasma Pi and bone measurements indicated marginal phosphorus depletion. 5. In another experiment excessive dietary phosphorus (11.9 g PNP/kg) fed in a cross-over design caused small adverse effects on shell production, increased food intake and body weight and increased plasma Pi content, while there was no relationship between shell weight and plasma Pi concentration. 6. The results are consistent with an indirect effect of plasma phosphorus accumulation on shell formation, probably via an inhibitory effect on skeletal calcium release, in addition to any effect of excess dietary phosphorus on intestinal calcium availability. 7. Phosphorus requirement and status in the laying hen are complicated by the failure to recognise the contribution of digestible phytate-phosphorus to the available phosphorus supply. 相似文献
5.
A. W. WALKER 《British poultry science》1998,39(5):696-699
1. When laying hens are stressed some retain their eggs in the shell gland beyond the normal time of laying and this can result in the deposition of extra-cuticular calcium which makes brown eggs appear paler. 2. Three different types of enriched modified cage were compared: the location where eggs were laid was recorded and shell colour was measured using a reflectometer. 3. In 2 types of cage with enclosed nest boxes more eggs (80%) were laid in the nests than in a design with nest hollows in the open part of the cage (41%). 4. The eggs from the cages with enclosed nests were darker (had less extraneous calcium) than those with open nest hollows. This implies that in the designs with nest boxes fewer eggs had been retained and the hens may have been less stressed. 5. The results support previous evidence that to reduce stress and improve welfare it is desirable to provide enclosed nest sites for caged laying hens. 相似文献
6.
1. Daily injection of hypothalameal extract (HE) and adenohypophyseal extract (AE) into hens aged 56 or 67 weeks for 14 d did not significantly influence the production of shell-less (SL) or ultra-thin-shell (UTS) eggs. 2. The injection of HE significantly increased hard-shell (HS) egg production in the younger hens. 3. Neither AE nor HE affected egg weight, serum calcium, gain in body weight or food consumption. 4. In a third experiment hens selected for poor egg production laid at a rate of 58% of which 36% were SL, 29% UTS and 35% HS eggs. Whereas the production rate of the good layers was 65% of which 1-4% were SL and 1-4% were UTS eggs. 5. Specific gravity of HS eggs, serum calcium, weight of ovary, oviduct, or adenohypophysis did not differ between good and poor layers. 6. Since SL and UTS eggs are easily overlooked the decrease in egg production with age may be as great as indicated by normal production records; the problem may be concerned more with the mechanism of shell formation. 相似文献
7.
Administration of 1,25 dihydroxyvitamin D3 (1,25(OH)2D3) to lactating dairy cows resulted in increased dietary calcium absorption and elevated concentrations of plasma calcium. Dietary magnesium absorption was unaffected by 1,25(OH)2D3 however, plasma magnesium concentration was depressed. Injections of 1,25(OH)2D3 were effective in elevating plasma calcium concentrations in both normal and hypomagnesaemic cows. This indicates a potential use for 1,25(OH)2D3 to prevent and treat hypocalcaemic cows with or without concurrent hypomagnesaemia. 相似文献
8.
White Leghorn hens were fed either a conventional diet containing 40 gCa/kg from oyster shell, or one low in Ca (3 g/kg) with oyster shell offered separately. In experiment 1 access to oyster shell was unrestricted; in experiment 2. Access was time-restricted to the first 6 h of the photophase of the 14L:10D photoperiod. Irrespective of time-restriction, hens offered oyster shell laid heavier eggs, but shell thickness was reduced. On days on which only ovulation occurred, time-restricted hens consumed significantly less Ca than unrestricted hens. In contrast, on days on which only oviposition occurred, time-restricted hens consumed significantly more Ca than unrestricted hens. These results suggest that when access to oyster shell is time-restricted to morning hours Ca consumption occurs in response to a Ca deficit persisting from the previous period of shell calcification. 相似文献
9.
K. M. SCHNEIDER G. B. PARKINSON J. C. HOUSTON D. D. LEAVER 《Australian veterinary journal》1985,62(3):82-85
Sheep given a liquid diet low in calcium and magnesium by infusion directly into the abomasum developed concurrent hypocalcaemia and hypomagnesaemia, with plasma concentrations of calcium and magnesium decreasing to 2.0 and 0.4 mmol/l respectively. Treatment of these hypomagnesaemic sheep with 1,25 dihydroxyvitamin D3 (1,25(OH)2 D3) increased the plasma calcium, magnesium and phosphorus concentrations with plasma calcium increasing to 2.5 mmol/l and plasma magnesium to 0.6 mmol/l. Plasma magnesium increased despite a small but significant increase in the daily excretion of magnesium in the urine, and the amount of magnesium derived from either bone and/or intestine must have been greater than the amount lost in the urine. Since in other experiments we have demonstrated that plasma calcium remains within the normal range when a liquid diet adequate in magnesium but low in calcium is infused, these results imply that either synthesis of and/or end organ response to 1,25(OH2) D3 is impaired in magnesium deficient sheep. 相似文献
10.
A B Gilbert 《British poultry science》1969,10(1):83-88
When fed a calcium‐deficient diet normal hens stopped laying within 10 days, but hens with a thread in the shell gland continued to lay soft‐shelled eggs for about 9 weeks. This finding supports the hypothesis that calcium loss is an important factor in the regulation of reproductive activity in the domestic fowl. 相似文献
11.
Aged laying hens at oviposition were given four levels of dietary vitamin D3 and three levels of 1,25-dihydroxyvitamin D3 (1,25[OH]2D3) to determine the effects of the additives on the medullary and endosteal bone. Oxytetracycline hydrochloride labeling and histomorphometry of undecalcified sections were used in the determination of changes in medullary bone and endosteal surface of mid-diaphyseal tibiotarsal bones. Treatment with 1,25(OH)2D3 increased mineralized medullary bone area, endosteal surface length, amount of tetracycline labeling in medullary and endosteal bone, total number of osteoclasts on endosteal and medullary bone, and appositional rate of mineralizing bone. Vitamin D3 increased mineralized medullary bone area and total tetracycline labeling in endosteal bone but decreased endosteal mineral apposition rate. Medullary bone matrix with no mineral was observed only in the group receiving neither supplement. These areas were much larger than typical osteoid seams usually seen in trabecular bone. Both 1,25(OH)2D3 and vitamin D3 were effective in stimulating bone formation and retention of mineral within medullary bone matrix at oviposition. 相似文献
12.
1. Uterovaginal junction (UVJ) tissues were collected 24 h after artificial insemination (AI) from 85- and 125-week-old broiler breeder hens in three physiological states: laying hard shell eggs (HS), laying shell-less eggs (SL) and non-laying (NL). This was confirmed by egg production records and visual appraisal of the oviduct at the time of necropsy. 2. Three longitudinal sections of each UVJ were evaluated microscopically and sperm host glands (SHG) were scored in 5 categories: glandular morphology evident but not lumen present, basophilic stained epithelium and no spermatoza present, glands that contained one to five spermatozoa; glands that contained 6 to 20 spermatozoa and glands that contained more than 20 spermatozoa. 3. Laying hens (HS and SL) at 85 weeks of age had significantly more sperm host glands (SHG) containing spermatozoa than NL hens. At 125 weeks of age HS and SL hens had significantly more unscorable glands. 4. The only category that showed no difference between age and physiological status group was the empty category. No significant differences were observed for any gland category in 82- and 125-week-old NL hens. 5. A greater proportion of the 85-week-old group of HS and SL hens had more SHG containing spermatozoa and fewer unscorable glands that the 125-week-old birds. The only category that showed any difference within the SL group was the low category. 相似文献
13.
Voluntary food and calcium intake by the laying hen 总被引：2，自引：1，他引：1
Two experiments, each of 40 d duration, are described in which a diet rich in calcium (3.5% Ca) or one deficient in calcium (1% Ca), but with oyster shell offered separately, were fed ad libitum to four laying hens. The voluntary consumption of food and oyster shell was automatically recorded every 2 h. The hourly consumption of the high Ga diet increased during the afternoon while the daily pattern of consumption was modified by the position of the egg in the clutch.
When the low Ca diet was fed with oyster shell, the daily consumption was increased but the effect of the position of the egg in the clutch was reduced. The ingestion of oyster shell was very high between 16.00 and 20.00 h when egg calcification was in progress; after the last oviposition of the clutch this elevated level of intake remained though to a lesser degree. In relation to the stage of egg formation, the voluntary intake of oyster shell increased sharply between 4 and 12 h after the former oviposition.
These results confirm that the laying hen can discriminate between food and calcium intake. It seems that appetite for calcium is firstly related to light‐dark cycles with a modulation of the afternoon peak by ovulation and then egg shell calcification. 相似文献
14.
Food and calcium intake and egg shell strength were measured for 24 d with 40 laying hens fed on a daily ration of either 120 g of an all‐mash diet containing 3.25% Ca or 111 g of a 0.6% Ca diet plus 8.7 g of oyster shell. The additional calcium source was offered for a 3¼‐h period beginning at 09.00, 14.00 or 17.15 h.
Consumption of oyster shell was lowest in the morning. When the calcium meal was offered at this time, the hens slightly increased their calcium ingestion on oviposition days. However, calcium intake was higher on ovulation days when oyster shell was offered after 14 h. In each case, actual requirements seemed to be one of the main factors for determining calcium appetite.
Variations of food intake in relation to laying cycle were evident with the control diet but disappeared when oyster shell was offered separately in the afternoon. Consumption of low Ca diet was greater than that of control diet only when oyster shell was given in the late afternoon of days without ovulation.
The best egg shell quality was obtained by offering oyster shell between 14.00 h and 17.15 h but the difference with control was rarely significant. Practically it is recommended that oyster shell is given at least 3 h before light extinction. 相似文献
15.
试验旨在比较洪江雪峰乌骨鸡和罗曼粉蛋鸡的鸡蛋营养成分和蛋品质,为洪江雪峰乌骨鸡蛋用新品系选育提供依据。随机选取40周龄的洪江雪峰乌骨鸡(绿壳)、洪江雪峰乌骨鸡(粉壳)和罗曼粉壳蛋鸡各100只,每品种鸡随机分为5个重复,每个重复20只,在相同饲粮和饲养管理方式下进行饲养,45周龄收集鸡蛋检测营养成分和蛋品质指标。结果表明:洪江雪峰乌骨鸡绿壳蛋的蛋黄比例极显著高于罗曼粉壳蛋(P<0.01),蛋重、蛋壳厚度、哈氏单位极显著低于罗曼粉壳蛋(P<0.01),洪江雪峰乌骨鸡粉壳蛋的蛋重和蛋壳厚度极显著低于罗曼粉壳蛋(P<0.01);洪江雪峰乌骨鸡蛋中的多不饱和脂肪酸和硒元素含量均极显著高于罗曼粉壳蛋(P<0.01),洪江雪峰乌骨鸡绿壳蛋胶原蛋白含量极显著高于罗曼粉壳蛋(P<0.01)。综上所述,洪江雪峰乌骨鸡鸡蛋蛋黄比例高,蛋黄多不饱和脂肪酸、胶原蛋白、硒和锰含量高,适合作为优质禽蛋开发。 相似文献
16.
本试验旨在研究凝结芽孢杆菌对感染沙门氏菌前后蛋鸡生产性能、蛋品质的影响,并探究其对感染沙门氏菌蛋鸡血浆生化指标的影响。将400只沙门氏菌阴性、体况健康的京红商品代蛋鸡根据产蛋率无显著差异(P0.05)原则随机分成4组(A组、B组、C组和D组),每组5个重复,每个重复20只鸡。对照组(A组和C组)饲喂基础饲粮,凝结芽孢杆菌组(B组和D组)在基础饲粮中添加2.5×1010CFU/kg凝结芽孢杆菌;饲喂1周后,C组和D组连续2 d定量口服肠炎沙门氏菌悬浮液(1×108CFU/mL),A组和B组口服等量无菌磷酸盐缓冲液(PBS),继续饲养3周。结果表明:1)感染沙门氏菌前,凝结芽孢杆菌对蛋鸡生产性能无显著影响(P0.05)。感染沙门氏菌后,沙门氏菌显著降低了蛋鸡平均日采食量(P0.05);凝结芽孢杆菌极显著降低了蛋鸡料蛋比(P0.01),显著降低了平均日采食量(P0.05)。2)感染沙门氏菌前,凝结芽孢杆菌极显著增加了蛋鸡蛋壳重/蛋重(P0.01)。感染沙门氏菌后,沙门氏菌和凝结芽孢杆菌对蛋鸡蛋品质指标均无显著影响(P0.05)。3)感染沙门氏菌后,凝结芽孢杆菌显著降低了血浆总胆固醇和甘油三酯含量(P0.05);沙门氏菌显著降低了血浆总胆固醇、甘油三酯和钙含量,显著提高了血浆谷草转氨酶活性(P0.05),极显著提高了血浆碱性磷酸酶活性(P0.01);凝结芽孢杆菌与沙门氏菌对血浆总蛋白含量、钙/磷及谷草转氨酶活性有显著交互作用(P0.05)。综上,凝结芽孢杆菌可改善蛋鸡生产性能和蛋品质,在蛋白质代谢、脂质代谢、肝功能和钙磷吸收上都具有一定程度的改善作用。 相似文献
17.
Background
Cracked shells, due to age related reduction of shell quality, are a costly problem for the industry. Parallel to reduced shell quality the skeleton becomes brittle resulting in bone fractures. Calcium, a main prerequisite for both eggshell and bone, is regulated by estrogen in a complex manner. The effects of estrogen, given in a low continuous dose, were studied regarding factors involved in age related changes in shell quality and bone strength of laying hens. A pellet containing 0.385 mg estradiol 3-benzoate (21-day-release) or placebo was inserted subcutaneously in 20 birds each of Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB) at 70 weeks of age. Eggs were collected before and during the experiment for shell quality measurements. Blood samples for analysis of total calcium were taken three days after the insertion and at sacrifice (72 weeks). Right femur was used for bone strength measurements and tissue samples from duodenum and shell gland were processed for morphology, immunohistochemical localization of estrogen receptors (ERα, ERβ), plasma membrane calcium ATPase (PMCA) and histochemical localization of carbonic anhydrase (CA).Results
Estrogen treatment increased shell thickness of both hybrids. In addition, shell weight and shell deformation improved in eggs from the brown hybrids. The more pronounced effect on eggs from the brown hybrid may be due to a change in sensitivity to estrogen, especially in surface epithelial cells of the shell gland, shown as an altered ratio between ERα and ERβ. A regulatory effect of estrogen on CA activity, but not PMCA, was seen in both duodenum and shell gland, and a possible connection to shell quality is discussed. Bone strength was unaffected by treatment, but femur was stronger in LSL birds suggesting that the hybrids differ in calcium allocation between shell and bone at the end of the laying period. Plasma calcium concentrations and egg production were unaffected.Conclusions
A low continuous dose of estrogen improves shell strength but not bone strength in laying hens at the end of the laying period. 相似文献18.
1. Seventeen 32-week-old White Leghorn laying hens were induced to become deficient in calciferol or in calcium (laying thin or soft shelled eggs) by withdrawing either cholecalciferol (27.5 micrograms/kg diet) or calcium (31 g/kg diet) supplements from the control diet. 2. The metabolic fate and metabolic clearance rate (MCR) of intravenously injected 3H-oestradiol-17 beta were then monitored for 40 min. 3. In both the calciferol and calcium-deficient groups a major oestrogen sulphate pathway was particularly affected, resulting in a decreased conversion of oestradiol-17 beta-3-sulphate to oestradiol-17 alpha-3-sulphate, with a concomitant reduced MCR of oestradiol-17 beta from plasma. 4. The metabolic defect was corrected by feeding the control diet. 5. Because the metabolic defect observed in calciferol deficiency occurred in Ca deficiency in a more severe form, we conclude that the more immediate cause was calcium rather than calciferol deficiency. To our knowledge, this is the first observation of a calcium-deficient effect on oestrogen sulphate metabolism in vivo. 相似文献
19.
本试验旨在研究京红1号商品代蛋鸡产蛋后期在小麦-DDGS(玉米酒精糟及可溶物)型饲粮中钙的适宜需要量,在充分利用非常规饲料资源的同时为京红1号商品代蛋鸡营养标准的制定提供科学依据。试验采用360只52周龄京红1号商品代蛋鸡,随机分成4个处理,每个处理6个重复,每个重复15只鸡。试验基础饲粮为小麦-DDGS型日粮,各组钙水平分别为3.50%、3.89%、4.28%、4.67%。试验期6周。结果表明:与3.50%钙水平组相比,4.28%钙水平组料蛋比显著降低,而3.89%、4.28%、4.67%钙水平组间的料蛋比无显著差异;4.28%钙水平组的蛋壳厚度显著高于3.50%钙水平组,蛋黄颜色显著高于3.50%、3.89%钙水平组;不同钙水平对其他生产性能和蛋品质指标均无显著影响。饲粮钙水平和蛋壳厚度回归方程为y=-0.0528x^2+0.4668x–0.676(R^2=0.9862),据此方程计算得到日粮最佳钙水平为4.59%。结果提示,京红1号蛋鸡产蛋后期小麦-DDGS型饲粮中钙水平推荐量为4.28%~4.59%。 相似文献
20.
旨在利用从藏灵菇中筛选的可显著降低血清胆固醇和耐受胃肠道逆环境的副干酪乳杆菌KL1菌株制备微生态制剂,探讨该制剂在低胆固醇鸡蛋生产中对蛋鸡生产性能、蛋品质及鸡蛋中胆固醇含量的影响。本试验将120只30周龄健康状态良好且产蛋率接近的农大3号矮小蛋鸡随机分为低、中、高剂量试验组和对照组,每组5个重复,每个重复6只蛋鸡,试验组在基础饲粮中分别添加105、106、107 CFU·（只·d）-1副干酪乳杆菌KL1微生态制剂,对照组饲喂基础饲粮,连续饲喂10周。对蛋鸡的生产性能、蛋品质和鸡蛋中的胆固醇进行测定和计算。结果表明：1）中剂量组的蛋鸡饲养日产蛋率与对照组相比有显著提高（P<0.05）;2）与对照组相比,中、高剂量组的蛋壳强度、蛋壳厚度和血清钙水平有显著提高（P<0.05）,蛋黄相对重有极显著提高（P<0.01）;3）低、中、高剂量组的蛋黄胆固醇含量及血清总胆固醇（TC）、甘油三酯（TG）含量均极显著低于对照组（P<0.01）;高剂量组的血清高密度脂蛋白胆固醇（HDL-C）和低密度脂蛋白胆固醇（LDL-C）含量分别极显著高于对照组（P<0.01）和显著低于对照组（P<0.05）。在饲粮中添加副干酪乳杆菌KL1微生态制剂可显著提高蛋鸡生产能力和蛋壳品质,降低鸡蛋中胆固醇含量,总体来看,以106 CFU·（只·d）-1作为最终添加剂量效果最佳,在低胆固醇鸡蛋的生产中具有良好的应用价值。 相似文献