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1.
In this study we investigated the temporal relationship between ovulation, egg formation, oviposition and the changes in plasma concentrations of progesterone, luteinizing hormone and estradiol-17beta during the egg laying cycle in farmed ostriches. In 10 egg-producing birds, transcutaneous ultrasound scanning was performed at 3h intervals and blood sampling at hourly intervals during a period of at least 48h (one egg laying cycle). In hens (n=8) that ovulated during the observational period, the ovulated egg was first detected 2h after oviposition; thus, ovulation occurred shortly after oviposition in all birds. During the period between two consecutive ovipositions, the developing egg remained for 9h in the proximal part (infundibulum, magnum or isthmus) and for 39h in the distal part of the oviduct (uterus). In ovulating hens, plasma progesterone concentrations showed a characteristic and consistent profile: from basal levels of around 0.1ng/ml concentrations started to increase 12h before oviposition, reached an average maximum of 3.5ng/ml at 3h before oviposition and returned to basal levels 3h and 30min after oviposition. Changes in plasma luteinizing hormone and estradiol-17beta concentrations showed comparable patterns of elevation and decline relative to the timing of oviposition and ovulation. However, variation in their individual basal concentrations was generally larger and peak values were less conspicuous than those of progesterone. In non-ovulating hens (n=2) neither progesterone, nor luteinizing hormone nor estradiol-17beta showed elevations to peak concentrations before oviposition. These data demonstrate that during the egg laying cycle of ostriches, events such as ovulation, egg development and oviposition evolve according to a rather strict time schedule, and that progesterone, luteinizing hormone and estradiol-17beta reach peak concentrations shortly before ovulation. Additionally, our findings also show that on-farm ultrasound scanning is a useful technique to discriminate between ovulating and non-ovulating hens.  相似文献   

2.
矮小型褐壳蛋鸡产蛋时间和间隔的统计分析   总被引:4,自引:0,他引:4  
本文对880只纯系矮小型褐壳蛋鸡的产蛋时间进行了连续5天的观察,分析结果表明,矮小型褐壳蛋鸡的产蛋时间集中在上午12时以前,并以9:00~10:00期间产蛋最为密集,占全天产蛋的19.5%。连产内第一枚蛋产出时间集中在上午(89:33%),以7:00~9:00间产蛋最多(49.71%);而最后一枚蛋产出时间集中在下午(71.20%),以2:00~4:00间产蛋最多(36.58%)。矮小型褐壳蛋鸡连产内产蛋间隔范围为22.35~31.15小时,每枚蛋平均间隔高峰在24小时(36.0%),群体平均产蛋间隔为25.08小时。相邻连产间间隔时间的变异范围很大,最短为38.0小时,最长达100.45小时。  相似文献   

3.
The study was performed to determine the hormonal status of mature germline chimeras obtained by blastodermal cell transfer from chicken embryos of a donor breed [Green-legged Partridgelike breed (GP) x Araucana (AR)] to those of a recipient breed [White Leghorn (WL)] being at the same stage of embryonic development. The egg-laying chimeras and WL hens (control) of the same age were used in the experiment. At first, blood samples were taken from each bird at 0.5, 5, 12.5 and 18.5 h following oviposition. Subsequently, the chimeras and the WL hens were decapitated 1-2 h after ovulation. A stroma and the following follicles were isolated from the ovary: white normal (1-4, 4-6 and 6-8 mm), white atretic and yellow preovulatory follicles (F4-F1). Sex hormones, progesterone (P4), testosterone (T) and oestradiol (E2) in blood plasma and ovarian follicles were determined radioimmunologically. The activity of the 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the granulosa and theca layers of the follicles was analysed histochemically. In chimeric chickens, a higher level of T in blood plasma during the ovulatory cycle was noticed. However, in the stroma, white prehierarchical and medium-size preovulatory ovarian follicles the level of T was significantly lower. With respect to E2, its elevated levels were found both in blood and in the ovarian follicles. There were no significant differences in P4 concentrations in blood plasma while in ovarian follicles a higher level was observed only in white 6-8 mm follicles. 3beta-HSD activity in granulosa and theca layers of the ovarian follicles in chimeras was not different from that in the WL hens. In conclusion, the results obtained indicate that germline chimeras exhibit significant alterations in sex hormone levels in the ovary and blood plasma, which in turn may affect their reproductive abilities.  相似文献   

4.
The aim of this study was to investigate the effects of suppression of plasma prolactin (PRL) concentration on circulating concentrations of luteinizing hormone (LH), progesterone (P(4)), estradiol (E(2)beta), pause days and egg production in birds later in the reproductive period. Twenty-four White Leghorn birds of same age group were divided into two groups of 12 in each. Birds of each group were administered s/c either with placebo (control group) or equal volumes of anti PRL agent (2-bromo-alpha-ergocriptine) solution containing at 100 microg/kg body weight/hen/week (treated group) from 72 to 82 weeks of age. Egg production and inter sequence pauses were recorded daily from both the groups. Plasma PRL, LH, E(2)beta and P(4) concentrations were estimated in blood samples collected at weekly intervals. At 77th weeks of age, blood samples from treated and control birds were obtained every 3h for 36h to study the surges of LH. It was found that plasma PRL concentration was lower (p<0.01) in bromocriptine treated birds with high concentrations of LH, its 3h LH surges, E(2)beta and P(4) in plasma. Higher egg production, less pause days in treated birds may be the result of low PRL concentration, associated with positively correlated responses of high concentrations of LH (with regular interval and duration of LH surges), E(2)beta and P(4) concentration required for completion of egg formation and oviposition. In conclusion, bromocriptine administration decreased (p<0.01) PRL concentration increased (p<0.01) steroid hormones and LH surges, for egg formation and oviposition and enabled the birds to lay more eggs even later in the productive period with the available resources under normal husbandry practices.  相似文献   

5.
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   

6.
The effects of selection under continuous light for reduced oviposition interval within a sequence of eggs on plasma luteinising hormone (LH) concentrations during the ovulatory cycle were investigated in lines of Australorps and White Leghorns maintained on a 24-h light:dark cycle. Selection did not significantly alter LH concentrations during mid-sequence cycles in either breed. In the control lines, concentrations were higher in the Australorps than in the White Leghorns before and at peak in mid-sequence cycles. The increase in egg production resulting from selection was associated with an advance in the mean time of lay of mid-sequence eggs in both breeds and, in the Australorps, with more pre-ovulatory LH peaks being initiated at the beginning of the open period of the ovulatory cycle. Selection reduced the time an egg spends in the oviduct and, in the Australorps, significantly reduced the interval between a pre-ovulatory LH peak and the oviposition of the egg currently in the shell gland. We suggest that selection under continuous light for reduced oviposition interval increased the rate of ovarian follicular maturation by a mechanism which did not involve an increase in pre-ovulatory concentration of plasma LH in a 24-h light-dark cycle.  相似文献   

7.
The objective of the present study was to establish the changes in plasma concentrations of LH, FSH, estradiol 17-beta (E2) and progesterone (P4), as well as to understand their temporal relationships during oestrus in mithun (Bos frontalis). The experiment was conducted on 11 mithuns during third or fourth postpartum oestrous cycle. Since oestrus onset the jugular vein blood samples were collected every 2 h for 72 and 96 h, respectively from the animals without and with standing heat. The LH, FSH, E2 and P4 concentrations were estimated in plasma. The P4 concentration was fluctuated throughout the oestrus period and the average P4 concentration was found significantly (p<0.05) lower on the day of oestrus onset. The multiple rises in LH and FSH concentrations above the basal level in spike like fashion were observed throughout the oestrus period irrespective of the occurrence of standing heat. A significant (p<0.01) gradual increase in the average daily E2 concentration was observed till day 2 following oestrus onset irrespective of the occurrence of standing heat. A significant (p<0.05) simultaneous increase in LH, FSH and E2 concentrations and a transient increase in P4 concentration at approximately the time of standing heat onset were observed. During investigation a definite temporal coupling between LH and FSH rises was absent throughout the oestrus period. The results suggest that (1) the multiple short-duration low-amplitude LH and FSH surges during oestrus may be crucial for the final maturation of ovulatory follicle and subsequent ovulation in mithun; (2) a differential mechanism for controlling LH and FSH secretions probably exists in mithun.  相似文献   

8.
Twenty-six Balady goats categorized according to parity into primiparous and pluriparous goats were used to investigate bacterial flora of the genital tract and hormonal profiles during the postpartum (PP) period. Escherichia coli and Staphylococcus aureus were isolated in pure or mixed culture from the uterus. Arcanobacterium pyogenes was isolated from swabs obtained from the vagina and cervix of one primiparous goat. Uteri and cervices but not vaginas were free of bacterial contamination by day 10 PP except for one pluriparous goat with scanty E. coli contamination on day 25 PP. Fluctuating oestradiol 17beta (E2) levels demonstrated resumption of follicular activity as early as day 13 PP in both parity groups. Progesterone (P4) levels remained low at basal levels throughout the study period. Higher concentrations of 15-keto-13,14-dihydroprostaglandin F2alpha (PGFM) were observed during the first week PP compared with the rest of the PP period. PGFM concentrations dropped to low basal level by day 10 PP and remained constantly low throughout the study period. P4, E2 and PGFM profiles were not different between the different parity groups. In conclusion, intrauterine infection is not common in goats with normal kidding. E. coli was the most common intrauterine bacterial isolate. E2 and P4 profiles were consistent with resumption of follicular growth but not ovulation. High PGFM concentrations coincided with the fast regression phase of uterine involution. Hormonal profile and bacterial contamination and clearance were similar to those reported in other related species and not related to parity.  相似文献   

9.
We investigated the effects of dietary copper and vitamin E in diets containing 6% rapeseed oil on the performance and the antioxidative and oxidative status of growing pigs. The 10 dietary treatments consisted of a basal diet (9 mg of vitamin E/kg feed, 15 mg of Cu/kg feed), the basal diet + 6% rapeseed oil (Diet 1; 18 mg of vitamin E/kg feed, 15 mg of Cu/kg feed), and Diet 1 plus supplements of vitamin E (0, 100, and 200 mg of dl-alpha-tocopheryl acetate/kg feed) and copper (0, 35, and 175 mg of Cu/ kg feed) in a 3 x 3 factorial arrangement of treatments. Eight or nine pigs were given ad libitum access to each diet from 25 to 100 kg of live weight. The inclusion of rapeseed oil tended (P < .10) to improve ADG and feed utilization. Compared with the addition of 35 mg of Cu/kg, the addition of 175 mg/kg improved growth rate and increased feed intake early in the experiment, but, over the total experiment, neither 35 nor 175 mg of Cu/kg affected performance. Compared with the addition of 100 mg of vitamin E/kg or no addition, the addition of 200 mg/kg reduced ADG over the total experiment (P = .05). The antioxidative and oxidative status of the pigs was evaluated in terms of blood and liver concentrations of antioxidants (alpha-tocopherol, ascorbic acid, vitamin A, superoxide dismutase, glutathione peroxidase), prooxidants (Cu), concentrations of lipids (triglycerides and cholesterol), fatty acid composition, thiobarbituric acid-reactive substances (TBARS), and clinical chemical (creatine kinase and glutamate-oxaloacetate-transaminase) and hematological variables that indicate the level of oxidative stress. There were no vitamin E deficiency signs or increased oxidative stress in pigs fed low dietary vitamin E levels, and no prooxidative effect of Cu was found. Increasing dietary levels of vitamin E increased the concentration of alpha-tocopherol in plasma and liver. Supplementation with Cu increased liver concentrations of Cu and alphatocopherol. The progression in liver TBARS was reduced by the addition of vitamin E and Cu. The addition of rapeseed oil changed the fatty acid composition of liver, increased alpha-tocopherol concentration in plasma and Cu concentration in liver, and reduced the rate of lipid oxidation in liver. In conclusion, even though the effects were minor, vitamin E, Cu, and rapeseed oil improved the antioxidative status of the live pigs.  相似文献   

10.
Changes in progesterone (P4), 17 beta-estradiol (E2) and 11-hydroxycorticosteroid (11-OHCS) concentrations in blood plasma were determined in daily intervals from the day of parturition to day 15 post partum (p.p.) in cows with physiological puerperium (n = 8), with puerperal endometritis (n = 6), and with placenta retention (n = 6). Cows with puerperium disorders (endometritis, placenta retention) had significantly higher P4 levels in the period from day 3 to day 7 p.p. than cows with physiological puerperium. E2 concentrations decreased to basal values following the parturition in cows with spontaneous parturitions and subsequent expulsion of the placenta. A delayed decrease in E2 concentrations after parturition and a significant increase on day 5 and day 7 p.p. were recorded in the group of animals with placenta retention. Significantly higher levels of 11-OHCS in blood plasma were detected by day 5 or by day 8 p.p. in cows with placenta retention and puerperal endometritis. Extraovarial sources of sexual steroids resulting in endocrine malfunctions are discussed as well as likely consequences for puerperium.  相似文献   

11.
研究了添加VA、VC和VE混合物(1.5 kg/t饲料)对浙东白鹅繁殖性能、血浆激素浓度和下丘脑-垂体-性腺轴基因mRNA水平的影响。结果显示:饲喂维生素混合物可显著提高浙东白鹅第1产蛋周期蛋重和受精率(P<0.05),但对第2产蛋周期产蛋量、蛋重、受精率和孵化率影响有限;饲喂维生素混合物可提高浙东白鹅第2产蛋周期内血浆FSH、P4、HCG和赖抱期、恢复期E2的浓度,降低LH浓度,改变浙东白鹅产蛋周期内FSH波动规律(P<0.05),降低下丘脑内PRLR、垂体内PRL和卵巢内PRLR基因的mRNA水平(P<0.05),提高卵巢内ESR2基因的mRNA水平(P<0.05),对下丘脑内GnRH、垂体内PRL和FSHβ、卵巢内PRL、ESR1和FSHR基因的mRNA水平影响不显著。因此,VA、VC和VE混合物可以通过影响繁殖期内部分血浆激素浓度变化,下调生殖轴PRLR mRNA水平以减弱PRL信号,从而改善浙东白鹅的繁殖性能。  相似文献   

12.
HyLine Brown laying hens at 30 weeks of age were treated twice daily with Fadrozole, a non-steroidal aromatase inhibitor (AI; 1 mg/kg body weight; i.m.) for six consecutive days; control hens received saline. Blood was collected every day 0.5 h after oviposition, i.e. just before AI treatment. Ovarian steroids: progesterone (P4), testosterone (T) and estradiol (E2), and iodothyronines: thyroxine (T4), triiodothyronine (T3) and reverse-triiodothyronine (rT3) were measured in blood plasma by radioimmunoassay methods. In AI-treated hens a gradual delay in oviposition time was observed. AI significantly decreased P4 and E2 levels, maximally by 43% on day 4 and by 74% on day 5, respectively, and elevated T level, maximally by 248% on day 4. Simultaneously, the increases in T4 and T3 levels with no changes in rT3 levels were observed. The maximal effect of AI on T4 and T3 levels was found on day 4 (60% increase) and day 5 (312% increase), respectively. Moreover, statistically significant, negative coefficient of correlation between E2 and T3 (r = -0.51), and positive coefficient of correlation between T and T3 (r = 0.42) in AI-treated hens were found. The results obtained indicate that in mature laying hens there is a strong relationship between ovarian steroids and thyroid hormones, and suppression of E2 synthesis not only disrupts ovarian function but also affects the activity of the thyroid gland and peripheral metabolism of thyroid hormones.  相似文献   

13.
1. Oviposition patterns in dwarf and normal pullets were compared after the dw gene had been introduced into a White Leghorn and an Australorp strain, which had been selected for reduced oviposition interval.

2. The dw gene increased oviposition interval by about 2 h and reduced clutch length by two‐thirds in both strains. It also decreased the occurrence of intervals shorter than 21 h and of membranous and soft‐shelled eggs in the White Leghorn strain, but had little effect on these traits in the Australorp. About two‐thirds of the 17% difference in rate of lay between dwarf and normal pullets could be attributed to the difference in oviposition interval.

3. It is suggested that the dw gene may be useful in overcoming certain physiological barriers when selecting for shorter oviposition interval.  相似文献   


14.
1. The effects of supplemental dietary vitamin E and organic selenium (Se), and their combination, on improving semen quality characteristics and antioxidative status were investigated in cockerels exposed to high ambient temperature.

2. A total of 36 Egyptian local cross males, 40 weeks old, were housed individually in cages in an open-sided building (average daily temperature ranged from 33 to 36°C and relative humidity from 60 to 70%). Birds were divided randomly into 4 experimental treatments (n?=?9 each): (1) control (basal diet without any supplementation with vitamin E or Se); (2) vitamin E (basal diet +200?mg α-tocopherol acetate/kg diet); (3) Se (basal diet +0·3?mg organic Se/kg diet); and (4) vitamin E?+?Se (basal diet +200?mg α-tocopherol acetate/kg diet +0·3?mg organic Se/kg diet).

3. Under heat stress conditions, inclusion of vitamin E and/or organic Se in the diets enhanced the semen quality traits, including the spermatozoa count and motility, and reduced the percentage of dead spermatozoa.

4. A combination of 200?mg/kg vitamin E with 0·3?mg/kg organic Se reduced the thiobarbituric acid reactive substance concentration in seminal plasma samples to about 28% of the controls; and also enhanced the seminal plasma glutathione peroxidase activity by two-fold compared with controls.

5. It was concluded that dietary vitamin E in combination with organic Se has a synergistic effect in minimising lipid peroxidation and improving the antioxidative status in seminal plasma of the domestic fowl, which probably translated into enhanced spermatozoa count, motility and reduced percentage of dead spermatozoa under heat stress conditions.  相似文献   

15.
Two experiments evaluated the relationship of vitamin E (source and level) and vitamin A (level) on the apparent absorption and retention of both vitamins in weaned pigs. Both experiments used a combined total of 460 crossbred pigs ([Yorkshire x Landrace] x Duroc), housed in elevated 1.2- x 1.2-m crates containing five pigs per pen. Experiment 1 was a 2 x 2 x 2 factorial arrangement of treatments in a randomized complete block design conducted in seven replicates. Levels of vitamin A (2,200 or 13,200 IU/kg), vitamin E (15 or 90 IU/kg), and two vitamin E sources (D-alpha-tocopheryl acetate [D-TAc] or DL-alpha-tocopheryl acetate [DL-TAc]) were evaluated over a 35-d period. Vitamin A or E levels and the two vitamin E sources did not affect pig performances to 20 kg BW. Serum retinol and alpha-tocopherol concentrations increased (P < 0.01) as the dietary level of each vitamin increased. Serum alpha-tocopherol declined as dietary vitamin E level increased when vitamin A level increased resulting in an interaction (P < 0.05). Serum alpha-tocopherol concentrations were higher (P < 0.05) at 35-d postweaning when D-TAc was the vitamin E source. Experiment 2 was a 3 x 2 factorial arrangement of treatments conducted in six replicates. Three levels of vitamin A (2,200, 13,200, or 26,400 IU/ kg) and two sources of vitamin E (D-TAc or DL-TAc) each provided at 40 IU/kg diet were evaluated over a 35-d period. Pig performances to 35-d postweaning were not affected by the dietary variables. Serum alpha-tocopherol (P < 0.01) and retinol (P < 0.05) concentrations increased as their respective vitamin level increased. Serum (P < 0.05) and liver (P < 0.01) alpha-tocopherol concentrations both declined as dietary vitamin A levels increased resulting in interaction responses. Serum alpha-tocopherol concentration was higher (P < 0.05) at 35-d postweaning when d-TAc was the vitamin E source. Dietary vitamin E sources had no effect on serum or liver retinol concentrations. These results demonstrated that both supplemental vitamin A and vitamin E increased in the blood as their dietary levels increased. However, as dietary vitamin A level increased, serum and liver alpha-tocopherol concentrations declined, suggesting a reduced absorption and retention of alpha-tocopherol when weaned pigs were fed high dietary vitamin A levels.  相似文献   

16.
1. The concentrations of 17 beta-oestradiol (E2) and progesterone (P) were determined in the plasma of layer breeder hens at the end of their first laying season, in relation to neoplasms of the oviduct, including magnum tumours and leiomyomas. 2. The plasma concentration of E2 was higher in tumorous than in non-tumorous hens indicating it may be involved in the development of oviduct tumours. 3. The plasma concentrations of P in tumorous and non-tumorous hens were not significantly different, suggesting no active role of P in the aetiology of the tumours. 4. The E2: P ratio was higher in tumorous than in non-tumorous hens. This ratio could be of value in predicting hens at risk of developing oviduct tumours.  相似文献   

17.
The effect of weaning the 4-5 heaviest piglets in the litter on day 33 of lactation and the remainder 2 days later (fractionated weaning) on plasma levels of prolactin, cortisol, oestradiol-17 beta (E2), progesterone (P4) and LH, as well as on the weaning to oestrus interval in primiparous sows was studied. Twelve crossbred sows were grouped into 6 pairs according to farrowing date and litter size. The litter of 1 sow in each pair (F) was weaned in 2 stages, and the other conventionally weaned at 35 days (C). Blood samples were collected via a permanent jugular vein catheter every 3 h from 9 a m to 9 p m daily throughout the experimental period, and intensively at 15 min intervals for 12 h on the day of first and final weaning and for 6 h on the day after each weaning. All sows were slaughtered following their first post-weaning oestrus and the reproductive organs were macroscopically examined. Lactational oestrus was not observed in any of the sows. Sows from 5 out of 6 pairs showed oestrus within 8 days of weaning and post-mortem examination showed normal ovulation. There was a tendency for the F sows to have a shorter weaning to oestrus interval, as compared with the C sows (5 of 6 pairs, 4.8 days v 5.6 days). The plasma levels of prolactin around weaning were not significantly different between the 2 groups. Within 6 h after final weaning, the prolactin concentrations decreased gradually from 7.6 and 8.7 to 1.6 and 1.7 microgram/l in the control and treatment groups, respectively. The plasma levels of cortisol, showing a diurnal rhythm (with the lowest level at 6 and/or 9 p m), did on no occasion differ between the 2 groups. On the day of final weaning, no diurnal rhythm was observed, with cortisol remaining high at 6 and 9 p m. The plasma levels of E2 and P4 were low until final weaning in both groups. After final weaning the E2 levels rose faster in the F sows than in the C sows, to 44.3 and 34.8 pmol/l, respectively, on day 2 (p less than 0.01). No significant differences in levels of plasma LH and the number of LH pulses were observed between the groups. After final weaning the average and base levels of LH and the number of LH pulse(s) increased significantly.  相似文献   

18.
This study was conducted to determine the effect of dietary selenium (Se) and vitamin E (Vit E) on various blood characteristics and the primary and secondary humoral immune response of lambs challenged with parainfluenza3 virus (PI3 V). Treatments included: 1) +Se/+Vit E, 2) -Se/+Vit E, 3) +Se/-Vit E and 4) -Se/-Vit E. The basal diet (-Se/-Vit E) was deficient in Se and Vit E. Sodium selenite (.2 mg Se/kg diet) and alpha-tocopherol acetate (20 mg Vit E/kg diet) were added to +Se and +Vit E diets, respectively, to provide adequate levels of each according to NRC recommendations. Following a 10-wk dietary adaptation and depletion period, lambs in all treatment groups were intratracheally inoculated with PI3 V on d 0 and 35 of the 70-d study. Prior to inoculation, whole blood and plasma glutathione peroxidase (GSH-Px) activities were higher (P less than .01) for +Se lambs. Whole blood and plasma GSH-Px increased (P less than .01) after primary viral inoculation in +Se lambs but not in -Se lambs. Serum immunoglobulin M (IgM) concentrations were enhanced (P less than .05) by Se supplementation on d 14, 35 and 49 of the study. Selenium and (or) Vit E did not affect serum immunoglobulin G (IgG) levels. Serum PI3 V antibody titers increased after inoculation on d 0 and 35 in all treatment groups. Titer levels appeared to increase more substantially for +Se lambs after primary inoculation, but increases were greater (P less than .01) for +Vit E lambs after secondary challenge.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
Three experiments conducted with weanling pigs evaluated the effects of vitamin E added to the drinking water or diet on plasma and tissue alpha-tocopherol concentrations. When natural or synthetic vitamin E was used, it was added at an IU-equivalent basis, but natural vitamin E was 73.5% (mg basis) of the synthetic vitamin E. Experiment 1 used 18-d-old weanling pigs (n = 120) in a 3 x 2 factorial arrangement of treatments in a randomized complete block design with 4 replicates. The first factor evaluated the dietary levels of natural vitamin E (RRR-alpha-tocopheryl acetate) added at 0, 50, or 300 IU/kg, whereas the second factor was the natural vitamin E added to the drinking water at 0 or 100 IU/L. Pigs were bled at periodic intervals, and 1 pig per pen was killed at the end of the 21-d trial and tissues (liver, heart, lung, and loin) were collected for alpha-tocopherol analysis. When vitamin E was not added to the diet or water, plasma alpha-tocopherol declined over the 21-d period. Although there were some interactions (P < 0.01), tissue and plasma alpha-tocopherol concentrations increased linearly when vitamin E was added to the diet or water. Experiment 2 was a 3 x 2 factorial in a randomized complete block design with 4 replicates. A total of 96 pigs weaned at 18 d of age, with an initial BW of 6.2 kg, were fed a nonvitamin E fortified diet, but natural or synthetic (all-rac-alpha-tocopheryl acetate) vitamin E was added to their drinking water at 50, 100, or 150 IU/L. Pigs were bled at 0, 3, 7, 10, 14, and 21 d postweaning, with tissues (liver, lung, heart, and loin) collected for alpha-tocopherol analysis at d 21. The results indicated that plasma alpha-tocopherol concentrations increased (P < 0.01) as vitamin E increased, with greater tissue alpha-tocopherol concentrations (P < 0.01) when natural vitamin E was provided. Experiment 3 was conducted in 2 replicates, but pigs (n = 60) were not provided vitamin E in the diet or water for 7 d postweaning, and then natural or synthetic vitamin E was added to the drinking water as in Exp. 2 (50, 100, or 150 IU/L). Pigs were bled at 0, 2, 4, 6, 8, 10, and 24 h after being provided vitamin E to evaluate the absorption from each vitamin E source and level. Plasma alpha-tocopherol increased quadratically (P < 0.01) and plateaued at 8 to 10 h for each treatment group. These results indicate that adding vitamin E to the pig's water supply at weaning was more effective in increasing plasma alpha-tocopherol than when it was added to the diet during the initial 14 d postweaning, and that natural vitamin E was a superior source compared with synthetic vitamin E.  相似文献   

20.
A previous study demonstrated that a dietary treatment of young geese with cholesterol and cholic acid raises lipid concentrations in the liver. The present study was carried out to investigate whether such a lipid accumulation caused by those hyperlipidemic compounds can be intensified by low dietary choline concentrations. Therefore, 38 eight-week old geese were divided into four groups of 9 or 10 animals each and received a basal diet poor in choline which consisted predominately of maize and soy protein isolate over a period of 8 weeks. Treatment factors were supplementation of diets with cholesterol and cholic acid (0 vs. 5 g of cholesterol and cholic acid each per kg) and supplementation of choline chloride (0 vs. 1.5 g/kg). Final body weights as well as carcass weights were neither influenced significantly by dietary treatment with cholesterol and cholic acid nor by low dietary choline concentrations. However, feeding diets supplemented with cholesterol and cholic acid markedly increased liver weights (two-fold), hepatic triglyceride (3.7-fold) and cholesterol (12-fold) concentrations and percentages of monounsaturated fatty acids at the expense of saturated and polyunsaturated fatty acids in the liver. In geese fed diets with cholesterol and cholic acid, insufficient choline supply did not intensify, but even slightly reduced hepatic lipid accumulation. Geese fed diets with cholesterol and cholic acid exhibited markedly increased levels of cholesterol, triglycerides and phospholipids in plasma and very low-density lipoproteins, regardless of the choline supply. Muscle tissue of geese fed diets supplemented with cholesterol and cholic acid exhibited also increased concentrations of triglycerides and cholesterol whereas the fatty acid composition of muscle lipids remained unchanged. Among geese without hyperlipidemic treatment, concentrations of triglycerides in plasma and very low-density lipoproteins as well as the concentrations of phosphatidylcholine in liver and muscle tissue were not reduced by low dietary choline concentrations. Therefore, it is suggested that those animals were able to synthesize endogenous sufficient choline.  相似文献   

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