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1.
Influence of dietary conjugated linoleic acid isomers on early inflammatory responses in male broiler chickens 总被引：5，自引：0，他引：5
1. The influence of dietary conjugated linoleic acid isomer (CLA, 0 and 10 g/kg) on the metabolic and physiological responses to immune stimulation induced by a single injection of Salmonella enteritidis lipopolysaccharide (LPS) or repeated injections of LPS and Sephadex G-50 was determined in male broiler chicks. 2. In experiment 1, 10-d-old chicks were fed on experimental diets for 14 d and half of the birds fed on each diet were injected intraperitoneally with LPS (1.5 mg/kg body weight). In experiment 2,7-d-old chicks were fed on experimental diets for 18 d. Immune stimulation was started at 19 d old and continued for 5 d. Half of the birds fed on each diet were injected intraperitoneally with 0.25 mg/kg body weight of LPS at 19, 21 and 23 d of age, and with 250 mg/kg body weight of Sephadex at 20 and 22 d of age to stimulate the immune system. 3. In experiment 1, giving CLA prevented an increase in blood heterophil to lymphocyte ratio 7 h after a single injection of LPS, and increases in plasma ceruloplasmin and alpha 1 acid glycoprotein (AGP) 24 h after the injection, but not 7 h after the injection. CLA also prevented a decrease in food intake for 24 h after LPS injection. 4. In experiment 2, the CLA diet partially prevented reductions in body weight gain and weight gain to feed intake ratio caused by repeated injections of LPS and Sephadex. Feeding CLA prevented increases in plasma ceruloplasmin and AGP at 24 d of age caused by repeated injections of LPS and Sephadex, but not at 20 d of age. 5. These results suggest that feeding CLA alleviates some undesirable metabolic and physiological changes induced by immunological stimulation in male broiler chicks. 相似文献
2.
It has been argued that stimulation of the immune system depresses performance. Accordingly, an experiment was conducted to determine the effect of dietary xylitol (150 g/kg diet) on growth and selected inflammatory responses in male broiler chickens. During the final 6 d of the experimental periods, chicks were injected with antigens: Escherichia coli lipopolysaccharide (LPS) on days 1, 3 and 5 and with Sephadex-G50 superfine on days 2 and 4 to stimulate macrophage functions. The immune stimulation reduced body weight gain and food intake, but enhanced alpha 1 acid glycoprotein (AGP) concentration and interleukin (IL-1) like activity in plasma. Feeding the xylitol diet partially, but significantly, prevented the reductions in body weight gain and food intake, without affecting the early stage of inflammatory responses triggered by LPS and Sephadex injections. 相似文献
3.
An experiment was undertaken to determine if dietary conjugated linoleic acid (CLA) influences the early stage of the inflammatory response caused by a single injection of Salmonella enteritidisi lipopolysaccharide (LPS) in male broiler chicks. Chicks (7 days old) were fed either 0 or 10 g CLA/kg in their diet for 21 days. At 28 days old, birds were injected intraperitoneally with 1.5 mg LPS/kg body weight after 12 h fasting. Changes in feed intake, rectal temperature and plasma α‐1 acid glycoprotein and ceruloplasmin concentrations were measured during 24 h after LPS injection. Chicks fed the CLA diet were fed more feed for 24 h, had a lower rectal temperature at 9 and 24 h and a lower plasma α‐1 acid glycoprotein concentration at 24 h after LPS injection than chicks fed the basal diet. Plasma ceruloplasmin concentration tended to be lower in chicks fed the CLA diet than in chicks fed the basal diet. The results suggest that dietary CLA alleviate undesirable early inflammatory response due to LPS injection in male broiler chicks. 相似文献
4.
1. The influence of age, sex and injection of Escherichia coli lipopolysaccharide (LPS) on the plasma concentration of alpha‐1 acid glycoprotein (AGP) was determined in broilers using the single radial immunodiffusion method.
2. Plasma AGP concentration increased in the 3 d after hatching, and then stabilised at 240 ± 33 μg/ml up to 14 d of age.
3. No sex‐related differences in plasma AGP concentration were observed up to 6 weeks of age.
4. A single injection of 900 μg LPS per chick resulted in a 5‐fold increase in AGP concentration compared with that in saline‐injected chicks. Multiple injections of LPS (200 μg/chick every 2d for 14d) caused only a 50% increase in AGP concentration. 相似文献
5.
1. A study was conducted to identify the specificity of insulin-glucose interactions in newly hatched broiler chicks. 2. Plasma insulin concentrations in fed chicks at one day post-hatch were lower than those at later ages and tended to increase up to d 7, while the concentrations from 1 to 7 d of age were lower than those in chickens of 10 to 28 d of age. 3. Plasma glucose concentrations were lowered for 60 min by injection of insulin at 10 and 40 microg/kg body weight (BW) in both 1- and 21-d-old chicks, showing that the hypoglycaemic effect of exogenous insulin is of larger magnitude but shorter duration in 1-d-old chicks. 4. The decrease in plasma glucose concentration at 60 min after insulin injection (10 and 40 microg/kg BW) was larger in 1- to 7-d-old chicks than in 14- to 21-d-old chickens. 5. These results indicate that newly hatched broiler chicks are under the control of specific insulin-glucose interactions characterised by low plasma insulin concentrations with high sensitivity to insulin. 相似文献
6.
Single injection of clenbuterol into newly hatched chicks decreases abdominal fat pad weight in growing broiler chickens 
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下载免费PDF全文 Daichi Ijiri Kanae Ishitani Mahmoud Mohamed Hamza El‐Deep Mana Kawaguchi Saki Shimamoto Yoshitaka Ishimaru Akira Ohtsuka 《Animal Science Journal》2016,87(10):1298-1303
The aim of the current study was to examine the effects of clenbuterol injection into newly hatched chicks on both the abdominal fat pad tissue weight and the skeletal muscle weight during subsequent growth. Twenty‐seven 1‐day‐old chicks were divided into two groups, receiving either a single intraperitoneal (i.p.) injection of clenbuterol (0.1 mg/kg body weight) or phosphate‐buffered saline (PBS). Body weight gain, feed intake and feed conversion ratio were not affected by clenbuterol injection during the 5‐week experimental period, while the abdominal fat pad tissue weight of the clenbuterol‐injected chicks was lower than that of the control chicks at 5 weeks post‐injection. Plasma non‐esterified fatty acid concentrations were significantly increased in the clenbuterol‐injected chicks, while plasma triacylglycerol concentrations did not differ. Additionally, the enzymatic activity of fatty acid synthase was lower in the liver of the clenbuterol‐injected chicks. Conversely, the skeletal muscle weights were not affected by clenbuterol injection. These results suggest that a single clenbuterol injection into 1‐day‐old chicks decreases the abdominal fat pad tissue weight, but may not affect skeletal muscle weights during growth. © 2015 Japanese Society of Animal Science 相似文献
7.
1. The experiment was conducted to investigate the effects of dietary sodium butyrate on the growth performance and immune response of broiler chickens. In experiment 1, 240 1-d-old chickens were allocated into 4 dietary groups (0, 0·25, 0·50 or 1·00 g sodium butyrate/kg) with 6 replicates each. In experiment 2, 120 1-d-old chickens were fed a control diet (without sodium butyrate) or 1·00 g sodium butyrate/kg diet. Half of the chickens fed on each diet were injected intra-peritoneally with 0·5 g/kg body weight of Escherichia coli lipopolysaccharide (LPS) at 16, 18 and 20 d of age. 2. There was no effect of dietary sodium butyrate on growth performance. On d 21, serum interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α) were decreased in chickens given 1·00 g sodium butyrate/kg, serum superoxide dismutase (SOD) and catalase activities were significantly increased, and malondialdehyde (MDA) was decreased by dietary sodium butyrate at 0·50 or 1·00 g/kg. On d 42, serum IL-6 was markedly decreased by dietary sodium butyrate, while 1·00 g sodium butyrate/kg greatly reduced MDA and increased catalase. 3. LPS challenge significantly reduced the growth performance of chickens. Serum IL-1β, IL-6, TNF-α, corticosterone, alpha-1 acid glycoprotein (AGP) and prostaglandin E(2) (PGE(2)) were increased in LPS-challenged chickens. Dietary sodium butyrate supplementation maintained the body weight gain and feed intake. Sodium butyrate supplementation inhibited the increase in IL-6 and AGP in serum at 16 d of age and TNF-α, corticosterone, AGP and PGE(2) at 20 d of age. Similar inhibitory effects of sodium butyrate in serum glucose and total protein concentrations were also found at 20 d of age. 4. The results indicated that dietary sodium butyrate supplementation can improve the growth performance in chickens under stress and that this may be used to moderate the immune response and reduce tissue damage. 相似文献
8.
Effects of thiamine and clenbuterol on body composition, plasma metabolites and hepatic oxygen consumption in broiler chicks. 总被引：1，自引：0，他引：1
1. We examined the effects of thiamine-hydrochloride (10 mg/kg body weight) and a beta-agonist, clenbuterol (50 microg/kg body weight), on plasma metabolites and hepatic oxygen consumption in female broiler chicks. 2. Clenbuterol, thiamine or both, dissolved in saline, were injected into thigh muscle on 2, 4 and 6 d of age. At 7 d of age blood samples in each treatment group were obtained and breast muscle and liver were weighed; liver slices were used for measurement of oxygen consumption. 3. Body weight gain was reduced by clenbuterol. Thiamine increased breast muscle weight as a proportion of body weight regardless of clenbuterol dose. Clenbuterol increased relative liver weight markedly, especially when chicks received thiamine also. 4. Clenbuterol increased plasma free fatty acid concentration in chicks treated with thiamine. Thiamine decreased plasma triglyceride regardless of clenbuterol dose. Plasma glucose concentration was decreased by both thiamine and clenbuterol. 5. The absolute rate of oxygen consumption in liver slices was greater in the thiamine-treated chicks; clenbuterol did not affect hepatic oxygen consumption. 6. These findings suggest that thiamine-induced energy expenditure results not only from thermogenesis in the liver, but also from increasing energy utilisation for muscle hypertrophy and this vitamin supplementation facilitates the lipolytic effects of the beta-agonist. 相似文献
9.
探讨山豆根多糖对PRRSV感染小鼠脾淋巴细胞分泌细胞因子水平的影响。将70只昆明种小鼠随机分为7组(A组、B组、C组、D组、E组、F组、G组),每组10只,雌雄各半,依据前期已经建立氧化应激模型的感染条件,D组、E组、F组、G组小鼠于试验第1、2、3天分别采用口服、滴鼻和腹腔注射3种途径联合感染PRRSV病毒原液1.0mL/只,A组、B组、C组给予生理盐水1.0mL/只。第4、5、6天,A、D组小鼠分别腹腔注射生理盐水,0.2mL/10g。B组小鼠腹腔注射5.0mg/kg的脂多糖(LPS)溶液,C组、E组、F组、G组小鼠分别腹腔注射不同剂量的山豆根多糖(200、50、100、200mg/kg)。供试小鼠均于第14天处死,并取其脾脏制备匀浆。采用ELISA检测脾匀浆中TNF-α、IL-1β、IL-6、IL-8、IL-10和MCP-1等细胞因子的水平。结果显示,PRRSV感染小鼠后能升高小鼠脾脏匀浆内TNF-α、IL-1β、IL-6、IL-8、IL-10和MCP-1水平,50mg/kg~100mg/kg剂量的山豆根多糖能降低上述细胞因子的水平。结果表明,山豆根多糖能有效降低PRRSV感染小鼠脾脏细胞因子的水平。 相似文献
10.
共轭亚油酸对免疫应激仔猪生长抑制的缓解作用 总被引：5，自引：0，他引：5
试验选用 72头 (2 8± 2 )d断奶的仔猪 ,采用 2× 2因子试验设计 ,研究共轭亚油酸 (CLA)是否有缓解仔猪免疫应激的作用。结果显示 ,添加CLA缓解了因注射脂多糖 (LPS)引起的日增重降低 (P <0 .0 5 ) ,并改善了试验全期的饲料转化效率 (P <0 .0 5 )。两次LPS刺激后 ,CLA抑制 (P <0 .0 5 )了由LPS诱导的血浆白细胞介素 6 (IL 6 )、肿瘤坏死因子 α(TNF α)和α 乙酰糖蛋白 (AGP)浓度的上升。在第 14d和 2 1d ,LPS刺激提高 (P <0 .0 5 )了血浆IL 1β和皮质醇含量 ,而CLA则降低了IL 1β和皮质醇含量。本试验证明 ,CLA能缓解免疫应激引起的仔猪生长抑制 ,其防止免疫应激诱导的生长抑制作用可能与CLA抑制炎性细胞因子的分泌有关 相似文献
11.
Shiro KUSHIBIKI Hiroyuki SHINGU Rika KAWASAKI Tokushi KOMATSU Fumiaki ITOH Atsushi WATANABE Eiko TOUNO Akinori OSHIBE Kazuo KATOH Yoshiaki OBARA Koichi HODATE 《Animal Science Journal》2008,79(3):375-381
One of the biological functions of bovine lactoferrin (LF) is modulation of the host defense system, including cytokine production and immune response. The aim of the present study was to investigate the effect of oral administration of LF in calves on lipopolysaccharide (LPS)‐induced metabolic and hormonal changes in inflammatory response. Thirty Holstein calves at 4 day of age were given one of three oral doses of LF (0, 1, 3 g/day) for 10 days (?10 day to ?1 day). They were injected i.v. with LPS (50 ng/kg bodyweight) the day (day 0) after the end of LF treatment. Plasma samples were obtained on ?10, 0 day (immediately before LPS injection), and at 2, 6, 12, 24, 48, 72, and 96 h after LPS injection. Plasma tumor necrosis factor‐α concentrations at 2 h after LPS treatment were lower (P < 0.05) in LF 1 g/day‐fed claves compared with LF 0 g/day (control) calves. On day 0 there were no significant group differences in plasma LF concentration. Plasma concentration of haptoglobin in control calves was elevated by LPS injection. In LF groups, plasma haptoglobin concentrations slightly increased after LPS injection, but those levels at 6–24 h were lower (P < 0.05) than in the control group. The LF treatment inhibited (P < 0.05) the reduction of plasma ferrin concentration in calves following LPS challenge. The concentration of plasma aspartate aminotransferase in calves treated with LF was lower (P < 0.05) than in control calves at 24–96 h after LPS treatment. The concentration of plasma insulin‐like growth factor‐1 (IGF‐1) in all groups was decreased by LPS treatment, while in the LF groups the IGF‐1 level was higher (P < 0.05) than in the control group. Plasma adrenocorticotropic hormone and insulin concentrations in LF groups were lower (P < 0.05) than in control calves at 2 h after LPS injection. These data suggest that LF has a substantial anti‐inflammatory effect on the modulation of the host defense system in preruminant calves. 相似文献
12.
The acute phase response to inflammation induces changes in the secretion of hepatic proteins. To examine the time course of an acute phase protein response in broiler chickens, the plasma levels of hemopexin (HX) and alpha1-acid glycoprotein (AGP) and liver HX mRNA were measured at various time points from 3 hr to 336 hr after an intraabdominal injection of either lipopolysaccharide (LPS), complete Freund's adjuvant, incomplete Freund's adjuvant, phytohemagglutin, or mineral oil. Uninjected chicks served as controls. The accumulation of liver HX mRNA began within 3 hr of stimulation and peaked at 12 hr. Relative to control levels, plasma HX and AGP levels increased by 6-12 hr postchallenge and peaked at 24 hr. Complete Freund's adjuvant and LPS treatments induced the greatest increase in plasma HX (threefold; P < 0.05). Plasma levels of HX and AGP returned to control levels at 336 and 168 hr postinjection, respectively. A second experiment demonstrated that turpentine induced a similar AGP response as LPS and that albumin is a negative acute phase protein. The results suggest that plasma levels of HX or AGP could be used as an indicator of the systemic component of a local inflammatory response in chickens. 相似文献
13.
Dietary L-carnitine increases plasma insulin-like growth factor-I concentration in chicks fed a diet with adequate dietary protein level 总被引：2，自引：0，他引：2
1. The effect of L-carnitine supplemented into experimental diets with varying dietary protein concentrations (50, 200 and 400 g/kg) on body weight gain and plasma insulin-like growth factor-I (IGF-I) concentration in chicks was examined. 2. Dietary L-carnitine supplementation provided 0, 200, 500 and 1000 mg/kg. Chicks were given the diet ad libitum for 10 d. 3. When L-carnitine was provided as 500 or 1000 mg/kg, body weight gain was significantly improved in birds receiving the 200 and 400 g protein/kg diets. 4. There was an interaction between dietary L-carnitine and protein content on plasma IGF-I concentration. L-carnitine supplementation had little influence on plasma IGF-I concentrations in birds receiving the low protein (50 g/kg) diet. When dietary L-carnitine concentrations were increased from 0 to 1000 mg/kg in the adequate protein (200 g/kg) diet, plasma IGF-I concentrations were also increased. However, when dietary L-carnitine content was more than 500 mg/kg in the 400 g/kg protein group, plasma IGF-I concentration decreased with increasing dietary L-carnitine content. 5. Body weight change correlated significantly with the alteration in plasma IGF-I concentrations in chicks given diets with adequate dietary protein. 6. In conclusion, the improvement in body weight gain caused by dietary L-carnitine supplementation was achieved when chicks were given their dietary protein requirement, which may be partially explained by an increase in plasma IGF-I concentration. 相似文献
14.
Abnormalities appeared a few hours after groups of 14-day-old chicks (Gallus domesticus) were injected intravenously with 15 mg/kg of endotoxin (LPS) from Salmonella gallinarum. Clinical illness without mortality was accompanied by significant (P less than 0.05) falls in body temperature, bursa weight, the main haematological parameters, serum iron (SI) and transferrin saturation (TS) and a significant increase in unsaturated iron-binding capacity. All responses, apart from bursa weight, SI values and total and differential white-cell counts, returned to normal within 24 to 48 h. LPS given daily for three consecutive days did not cause changes in the main haematological parameters during the 48 h period following the third injection. However body and bursa weight and heterophil counts were significantly depressed, whereas body temperature, SI and TS were affected biphasically, being first depressed and then raised above normal. Chicks injected with LPS daily for six consecutive days showed broadly similar responses but a persistent microcytosis was also present. 相似文献
15.
Dietary conjugated linoleic acid enhances spleen PPAR-gamma mRNA expression in broiler chicks 总被引：1，自引：0，他引：1
1. The anti-inflammatory effects of dietary conjugated linoleic acid (CLA) on broilers repeatedly challenged with lipopolysaccharide (LPS) were investigated. 2. Day-old broiler chicks were allotted into three treatment groups and fed on a control diet or diets containing 5.0 or 10.0 g CLA/kg diet. Six chicks from each treatment were injected with LPS (0.25 mg/kg body weight) at 16, 18 and 20 d of age. Splenic cyclooxygenase (COX) and inducible nitric oxide synthase (iNOS) activities, and prostaglandin E(2) (PGE(2)) and nitric oxide (NO) production as well as peroxisome proliferator-activated receptor-gamma (PPAR-gamma) mRNA expression were measured at 21 d of age. 3. Chicks fed 10.0 g CLA/kg diet had lower COX activities and PGE(2) production that the controls. Dietary CLA (10.0 g/kg) did not significantly diminish LPS-induced enhancement of COS-2 activity, inhibited the subsequent increase in PGE(2) production. 4. Regulation of COX-1 activity contributed to the difference in PGE(2) production. 5. CLA did not markedly attenuate the increase of iNOS activity and NO production caused by LPS challenge. Chicks fed CLA had lower iNOS activity and NO production than the controls. 6. Dietary CLA activated splenic PPAR-gamma mRNA expression and increased PPAR-gamma mRNA expression after LPS injection. 7. These results suggest that dietary CLA has immunomodulatory effects in the spleen by restricting basal PGE(2) and NO to lower levels and enhancing PPAR-gamma mRNA expression. During the inflammatory response, dietary CLA did not alleviate the increase in COX-2 and iNOS activities but enhanced PPAT-gamma mRNA expression. 相似文献
16.
研究N-乙酰半胱氨酸(NAC)对脂多糖(LPS)刺激仔猪免疫应激的影响。选取18头健康仔猪,随机分成3个处理(对照组、LPS组和NAC组),每个处理6个重复。对照组和LPS组饲喂基础日粮,NAC组饲喂基础日粮+500 mg/kgNAC。试验期为20 d。LPS组和NAC组于试验第10、13、20天腹膜注射100μg/kg BW的LPS,对照组注射相应剂量的灭菌生理盐水。第10、20天注射LPS后3 h采血,第21天屠宰,取小肠黏膜。结果表明:NAC缓解了LPS刺激导致的血浆和小肠黏膜中TNF-α、IL-6、PGE2含量的升高(P<0.05),缓解了小肠黏膜HSP70相对表达量的升高(P<0.05)。由此可见,日粮中添加500 mg/kg NAC可有效抑制LPS刺激导致的血浆及小肠黏膜中炎性因子的升高,缓解免疫应激。 相似文献
17.
《中国畜牧杂志》2019,(8)
本试验旨在探究饲粮中添加壳寡糖(COS)和鸡源屎肠球菌PNC01(PNC)对脂多糖(LPS)诱导的肉鸡炎症反应的调节作用。选取1日龄健康且体重相近的AA公雏560羽,采用2(LPS刺激/非LPS刺激)×2(添加COS/不添加COS)×2(添加PNC/不添加PNC)三因素试验设计,共8个处理,每处理7重复,每重复10只鸡,试验期21 d。采用玉米-豆粕型基础饲粮,试验饲粮分别在基础日粮基础上添加COS(200 mg/kg)和PNC(1×10~9 CFU/kg)。于试验第17、19、21天,刺激组腹腔注射LPS(1 mg/kg体重),对照组注射等量生理盐水。结果表明:LPS刺激降低肉鸡采食量(P<0.01),破坏肠道形态,降低盲肠食糜中丁酸含量和血清IgA水平(P<0.05),引起脾脏肿大,上调IL-1β和IL-8 mRNA表达(P<0.01);添加COS缓解LPS刺激肉鸡采食量的下降(P<0.05),提高盲肠丙酸和丁酸含量(P<0.05),COS降低脾脏指数和回肠IL-8mRNA表达量(P<0.05),有下调脾脏IL-1βmRNA表达的趋势(P<0.1);PNC可提高21 d肉鸡血清IgA含量(P<0.05),降低肉仔鸡脾脏指数(P<0.01);非LPS刺激时,同时添加COS和PNC可提高盲肠中乙酸含量(P<0.05)。可见,添加COS和PNC均能缓解LPS刺激导致的脾脏肿大,缓解炎症反应,改善LPS刺激对肉仔鸡的不利影响。 相似文献
18.
The impact of acute phase response (APR) on the plasma clearances of antipyrine, theophylline, phenytoin and nifedipine was studied using 50 female rabbits. APR was induced by a bolus intramuscular injection of Escherichia coli lipopolysaccharide (LPS, 50 microg/kg). No abnormal findings, other than an increase in rectal body temperature and the plasma concentration of interleukin-6 (IL-6), were observed in the LPS-treated animals. Twenty-four hours after LPS injection, the pharmacokinetic parameters of the four drugs were obtained following intravenous administrations of antipyrine (7 mg/kg), theophylline (5 mg/kg), phenytoin (10 mg/kg) and nifedipine (1 mg/kg). Total body clearances of antipyrine, theophylline, phenytoin and nifedipine in LPS-treated rabbits decreased, and terminal elimination half-life and the mean residence time of these drugs increased compared with those in the control rabbits. The apparent volume of distribution for phenytoin and nifedipine increased after the LPS injection, although the binding percentage of the drugs with plasma protein did not change. These results suggested that APR appears to decrease the plasma clearances of these drugs in rabbits, which may be due to the suppression of the activity of cytochrome P450 enzymes. 相似文献
19.
1. Three battery experiments were conducted with broiler chicks during the 2nd and 3rd week of life. Graded amounts of cholecalciferol (D3) were added to maize-soyabean meal diets that were designed to be (a) severely deficient in available phosphorus (P), (b) marginally deficient in calcium (Ca) or (c) adequate in both available P and Ca. 2. With diets containing 1.0 g available P and 6.3 g Ca/kg (assay 1), graded doses of D3 between 0 and 37.5 mu/kg produced linear (P 0.05) positive responses in both weight gain and tibia ash. With a D3 concentration of 1250 mug/kg, 250 times the requirement recommended by the NRC, bone ash was increased (P 0.05) over that of birds fed 37.5 mug/kg, and neither weight gain nor food intake were reduced. 3. With a P- adequate diet (4.5 g available P/kg) containing 8.5 g Ca/kg (assay 2), weight gain and bone ash increased linearly (P 0.05) upon supplementing the basal diet with 0, 2.5 and 5.0 mug D3/kg. Higher doses of D3 did not elicit further responses, and chicks fed on a diet containing 1250 mug D3/kg gained as fast and had bone ash values that did not differ from those of chicks receiving 5, 10, 20 or 40 mug D3/kg. 4. When the maize-soyabean meal basal diet was fortified with Ca and P to achieve adequate amounts of Ca (10.1 g/kg) and P (4.5 g available P/kg) in assay 3, dietary additions produced results similar to those obtained in assay 2 where P was adequate and Ca was slightly deficient. Again, chicks receiving a surfeit of D3 (1250 mug/kg) exhibited weight gains and bone ash values that were as great as those of chicks receiving 5, 10, 15 or 30 mug D3/kg. 5. It is apparent that young chicks have a high tolerance for excess D3, and chicks fed on diets that are severely deficient in available P continue to respond to D3 in excess of 37.5 mug/kg. 相似文献
20.
Buyse J Swennen Q Niewold TA Klasing KC Janssens GP Baumgartner M Goddeeris BM 《Veterinary immunology and immunopathology》2007,118(1-2):154-159
The objective of the present study was to evaluate the potential effects of dietary L-carnitine supplementation on acute phase protein response upon a lipopolysaccharide (LPS) challenge of male broiler chickens receiving a commercial broiler diet supplemented with 15 or 100 mg L-carnitine/kg or an unsupplemented (control) diet from 14 days of age onwards. At 28 days of age, eight chickens per dietary treatment were weighed and subcutaneously injected with 300 microg LPS from E. coli (100 microg LPS/ml saline) or 3 ml saline (unsupplemented group only). During the next 10 days, blood samples were taken repeatedly and analysed for their hemopexin (HX) and alpha-1 acid glycoprotein (AGP) levels. Extra dietary L-carnitine did not affect broiler performance. At day 1 postinjection, plasma HX and AGP levels were significantly increased in all treatment groups. However, the elevations in circulating HX and AGP levels were more pronounced in the L-carnitine supplemented chickens, especially in the 100mg L-carnitine group. It is concluded that extra L-carnitine in the diet of broiler chickens enhances or advances the acute phase protein response. The exact mode of action needs to be elucidated but seems to be consistent with a glucocorticoid mimicking effect. 相似文献