Antipyretic effect of oral sodium salicylate after an intravenous E. coli LPS injection in broiler chickens

A study was set up to investigate the influence of sodium salicylate on fever and acute phase reaction after lipopolysaccharide (LPS) injection in broiler chickens. An acute phase reaction was provoked through the intravenous injection of Escherichia coli LPS. Four oral doses of sodium salicylate were tested. Apart from body temperature, other inflammation indices, such as plasma corticosterone and ceruloplasmin, serum thromboxane B2 and zinc concentrations were monitored. Intravenous LPS induced a fever of about 1 degree C. A dose-dependent attenuation of the fever response of the chickens in the salicylate treated groups was observed. LPS-injected chickens also showed elevated plasma corticosterone and ceruloplasmin, while serum thromboxane and zinc concentrations decreased. Except for thromboxane B2, no linear relationship with increasing salicylate dose could be shown for the other blood variables. These data confirm that sodium salicylate is an effective antipyretic agent after injection of LPS in chickens, if used at an appropriate dosage. No dose-related change could be found for the other inflammation indices.     

Pharmacodynamics of tepoxalin, sodium-salicylate and ketoprofen in an intravenous lipopolysaccharide inflammation model in broiler chickens

de Boever, S., Neirinckx, E.A., Meyer, E., de Baere, S., Beyaert, R., de Backer, P., Croubels, S. Pharmacodynamics of tepoxalin, sodium‐salicylate and ketoprofen in an intravenous lipopolysaccharide inflammation model in broiler chickens. J. vet. Pharmacol. Therap. 33 , 564–572. The pharmacodynamic properties of tepoxalin, Na‐salicylate and ketoprofen were determined in an intravenous lipopolysaccharide (LPS) inflammation model in broiler chickens. The drugs were administered orally at a dose of 30, 50 and 3 mg/kg, respectively. LPS administration induces an increase in the intracellular expression of interleukin (IL)‐1β and IL‐6 and the secreted IL‐6 plasma concentration. Furthermore, an elevation in body temperature is noted. Despite pretreatment with a single dose of the drugs and LPS administration on the T_max of the drug after a second dose, no decrease was seen in systemic IL‐6 levels. The intracellular expression of IL‐1β in the heterophils was slightly decreased if LPS was administered in combination with each of the three drugs. Tepoxalin and Na‐salicylate administration had no significant effect on the LPS‐induced increase in prostaglandin E₂ plasma concentration, in contrast to ketoprofen. None of the three drugs were able to influence the elevation in body temperature after LPS administration. The pharmacokinetic properties of Na‐salicylate and ketoprofen were not altered in combination with LPS administration. However, LPS significantly decreased the AUC_{0→6 h} of the active metabolite of tepoxalin, RWJ‐20142, indicating a perfusion‐limited elimination for this molecule.     

Hypophagic and dipsogenic effect of the 5‐HT1A receptor agonist 8‐OH‐DPAT in broiler chickens

The effects of the 5‐HT_1A receptor agonist 8‐OH‐DPAT on food and water intake in male broiler chickens were investigated. The injection of 25 or 50 μg/kg of 8‐OH‐DPAT 15 min before refeeding in fasted animals produced a decrease in food intake. No effect was observed in drinking. The injection of 25 or 50 μg/kg of the 8‐OH‐DPAT 60 min after the start of refeeding did not produce any significant modification in food intake. No effect on drinking was recorded. The agonist 8‐OH‐DPAT injected 15 min before water presentation in water‐deprived chickens, produced an increased drinking 60 min after the presentation of water. No effect on food intake was observed. The results show that the effect on food intake of the agonist 8‐OH‐DPAT in fasted–refed broiler chickens was similar to those observed in mammals and layer‐strain chickens. However, the agonist did not alter significantly the food intake when the broilers were fed 60 min before the injection. These results are contrary to the observed effects in mammals and in layer‐strain chickens. Probably, the selection for rapid growth rate in broilers causes modifications in the feeding control pattern. The comparison between broilers and layers strain may be a useful tool to elucidate the complex mechanisms involved in food and water intake regulation in chickens.     

Disposition of sodium salicylate,flunixin and meloxicam after intravenous administration in broiler chickens

Three nonsteroidal anti-inflammatory drugs (NSAIDs) [sodium salicylate, flunixin (FLU) and meloxicam (MEL)] were administered intravenously to broiler chickens. Plasma concentrations were determined by high-performance liquid chromatography methods and pharmacokinetic parameters were calculated. After intravenous administration of sodium salicylate (50 mg/kg), FLU (1.1 mg/kg) and MEL (0.5 mg/kg), these drugs were eliminated from plasma with a mean half-life of 04.04, 05.45 and 03.20 h, respectively. Apparent volumes of distribution (0.39, 0.08 and 0.12 L/kg, respectively) indicated that tissue distribution was limited for the three drugs. Total body clearance was 70 mL/h.kg for sodium salicylate and 10 and 25 mL/kg.h for FLU and MEL, respectively. Based on the pharmacokinetic parameters these NSAIDs may offer possibilities for treatment of various conditions in chickens.     

The effect of melanocortin (Mc3 and Mc4) antagonists on serotonin-induced food and water intake of broiler cockerels

The current study was designed to examine the effects of intracerebroventricular injections of SHU9119 [a nonselective melanocortin receptor (McR) antagonist] and MCL0020 (a selective McR antagonist) on the serotonin-induced eating and drinking responses of broiler cockerels deprived of food for 24 h (FD24). For Experiment 1, the chickens were intracerebroventricularly injected with 2.5, 5, and 10 µg serotonin. In Experiment 2, the chickens received 2 nmol SHU9119 before being injected with 10 µg serotonin. For Experiment 3, the chickens were given 10 µg serotonin after receiving 2 nmol MCL0020, and the level of food and water intake was determined 3 h post-injection. Results of this study showed that serotonin decreased food intake but increased water intake among the FD24 broiler cockerels and that these effects occurred in a dose-dependent manner. The inhibitory effect of serotonin on food intake was significantly attenuated by pretreatment with SHU9119 and MCL0020. However, the stimulatory effect of serotonin on water intake was not altered by this pretreatment. These results suggest that serotonin hypophagia and hyperdipsia were mediated by different mechanisms in the central nervous system, and that serotonin required downstream activation of McRs to promote hypophagia but not hyperdipsia in the FD24 chickens.     

Food availability and the feeding and drinking behaviour of broiler chickens grown commercially

1. Field observations were made on the effect of food depth in pans on the feeding and drinking behaviour of commercially grown broiler chickens aged between 17 and 43 d. 2. The group of birds receiving less food in pans had longer visits to the pans, occupied their feeding space more completely, evicted each other more often from pans and were more 'competitive' and less 'relaxed' when feeding. 3. These observations provide data about the feeding and drinking behaviour of broiler chickens reared in commercial conditions and emphasise how environmental factors, particularly food management, can influence bird behaviour. 4. The potential for qualitative and quantitative changes of feeding behaviour to affect performance is also discussed.     

Peripheral ghrelin reduces food intake and respiratory quotient in chicken

Ghrelin injection, either centrally or peripherally strongly stimulates feeding in human and rodents. In contrast, centrally injected ghrelin inhibits food intake in neonatal chickens. No information is available about the mechanism and its relationship with energy homeostasis in chicken. Since ghrelin is predominantly produced in the stomach, we investigated the effect of peripherally injected ghrelin (1 nmol/100g body weight) on food intake and energy expenditure as measured in respiratory cells by indirect calorimetry for 24h in one-week-old chickens. Plasma glucose, triglycerides, free fatty acids, total protein and T(3) were measured in a separate experiment until 60 min after injection. Food intake decreased until at least 1h after intravenous ghrelin administration. The respiratory quotient (RQ) in ghrelin-injected chickens was reduced until 14 h after administration whereas plasma glucose and triglycerides concentrations were not altered. Free fatty acids and total protein levels also remained unchanged. Ghrelin did not influence heat production and this was supported by the absence of changes in plasma T(3) levels when compared to the control values. In conclusion, peripheral ghrelin reduces food intake as well as RQ and might influence the type of substrate (macronutrient) that is used as metabolic fuel.     

Pharmacokinetics of tylosin in broiler chickens

Biological availability and pharmacokinetic properties of tylosin were determined in broiler chickens after oral (p.o.) and intravenous (i.v.) administration at a dose of 10 mg/kg. The calculated bioavailability--F%, by comparing AUC values--p.o. and AUC--i.v., ranged from 30%-34%. After intravenous injection tylosin was rapidly distributed in the organism, showing elimination half-life (t1/2 beta) values of 0.52 h and distribution volume (Vd) of 0.69 L/kg, at a clearance rate (Cl) of 5.30 +/- 0.59 ml/min/kg. After oral administration, tylosin has a similar distribution volume (Vd = 0.85 L/kg), while the elimination half-life t1/2 beta of 2.07 h was four times bigger than after i.v. administration at Cl = 4.40 +/- 0.27 ml/min/kg. The obtained value tmax = 1.5 h for tylosin after oral administration indicates that using this antibiotic with drinking water in broiler chickens is the method of choice. However, a relatively low value Cmax = 1.2 micrograms/ml after oral administration of tylosin shows that dosing of this antibiotic in broiler chickens should be higher than in other food producing animals.     

日粮中添加腐植酸钠对肉仔鸡成活率及生长性能的影响

本试验旨在研究日粮中添加不同水平腐植酸钠对肉仔鸡成活率及生长性能的影响。选用1000只健康科宝商品肉仔鸡,随机分为5组,每组5个重复,每个重复40只鸡。对照组饲喂基础日粮,Ⅰ～Ⅳ组在基础日粮中分别添加黄霉素、1.0%腐植酸钠、2.0%腐植酸钠、1.0%腐植酸钠＋黄霉素。试验期49 d。结果表明,与对照组相比,各组肉仔鸡成活率均有明显提高,Ⅲ组平均日采食量显著提高（P＜0.05）,Ⅱ、Ⅳ组平均日增重显著提高（P＜0.05）,Ⅱ、Ⅲ、Ⅳ组料重比显著降低（P＜0.05）。综上所述,日粮中添加腐植酸钠可提高肉仔鸡的成活率,改善其生长性能,其中以添加1.0%腐植酸钠效果最佳,同时与黄霉素具有较好的配伍作用。     

Influence of dietary conjugated linoleic acid isomers on early inflammatory responses in male broiler chickens

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.     

Sodium bicarbonate and potassium bicarbonate supplements for broilers can cause poor performance at high temperatures.

1. Supplements of between 2 and 8 g of sodium bicarbonate (NaHCO3)/l in drinking water provided between 21 and 49 d of age to broilers at 31 degrees C increased growth after 35 d of age and food intake after 42 d of age compared to unsupplemented controls. The most consistent responses were observed with 2 g NaHCO3/l. 2. Differences in weekly water intakes with different concentrations of NaHCO3 in the drinking water did not equate with variations in weekly food intake and growth. 3. Unexpected high mortality from dehydration and nephrosis was observed with a 10 g NaHCO3/l supplement. This mortality was associated with major changes in blood acid-base balance and plasma electrolyte concentrations. 4. Dietary supplements of NaHCO3 gave significantly better food conversion and numerically better growth in broilers at 31 degrees C than supplements of potassium bicarbonate (KHCO3) providing similar dietary concentrations of bicarbonate. 5. Supplements of NaHCO3 were more toxic to broiler chickens when supplied in the drinking water than in the diet. This appeared to be related to the intake of sodium and alterations to cellular membrane ionic potential.     

Eating behaviour, and preprandial and postprandial correlations in male broiler and layer chickens

1. It has been suggested that broiler chickens have a disturbed satiety and hunger mechanism. The satiety mechanism for eating can be expressed as the positive correlation between meal length and the length of the preceding (preprandial) interval; the hunger mechanism for eating as the positive correlation between meal length and the length of the succeeding (postprandial) interval. An experiment was conducted to investigate eating behaviour of male broiler and layer chickens by measuring meal and interval lengths. 2. Eight male broilers and 8 male layer chickens were housed individually and visually isolated in floor pens (1 m2/pen) on wood shavings. From 4 to 7 weeks of age, eating behaviour of each bird was recorded for 3 h in two conditions each week. In the first condition, the birds were not deprived from feed. In the second condition, they were 24-h food deprived and feed was provided just before the observation started. Preprandial and postprandial correlations were calculated based on data of the non-deprived condition. Before and after each observation bird and feeder were weighed to measure weight gain and feed consumption during observation. 3. Under the non-deprived condition, the broilers spent initially more, but at a later age less time on eating. The broilers had fewer meals per hour, consumed more feed per hour, and had longer meal and interval lengths than the layer chickens. After 24-h feed deprivation, the broilers had a longer first meal, consumed more feed per hour and spent more time on eating than the layer chickens. Significant preprandial correlations but no postprandial correlations were found in the broilers. In the layer chickens, both significant preprandial and postprandial correlations were found. This indicates that for regulating eating behaviour, the satiety mechanism dominates the hunger mechanism in broilers, and satiety and hunger mechanisms are equally involved in layer chickens. 4. The typical eating behaviour of broilers and the calculated preprandial and postprandial correlations have given new indications that hunger and satiety mechanisms in broilers have changed compared with layer chickens. In broilers, there is no lower set point, but only an upper set point for controlling eating behaviour, which suggests that broilers eat to their maximal physical capacity.     

Peripheral leptin effect on food intake in young chickens is influenced by age and strain

The acute effect of leptin on the regulation of food intake was investigated in layer and broiler chickens. In an initial study, we observed that a single intraperitoneal injection of recombinant chicken leptin (1 mg/kg BW) dramatically reduced (38%) food intake in 56-day-old layer chickens, more moderately reduced (15%) food intake in 9-day-old layer chicks, and had no significant effect in 9-day-old broiler chicks. In a subsequent study, body weight and plasma concentrations of leptin were measured weekly in layer and broiler chicks from day 1 to 35 of age and brain leptin receptor and neuropeptide Y (NPY) mRNA expression were analyzed at 1, 9, and 35 days of age. At day 1 of age, peripheral concentrations of leptin were significantly greater in layer than broiler chicks. Subsequently, despite increases in body weight and differences in growth rates between layer and broiler chicks from day 8 to day 35 of age, peripheral concentrations of leptin were constant and similar in both genotypes. Leptin receptor and NPY mRNA were expressed in brain from day 1 in chicks of both genotypes and increased significantly to day 35 of age. These observations provide evidence that the inhibitory effect of leptin on the regulation of food intake in growing chicks is an age dependent process. Furthermore, acquisition of the anorectic effect of leptin is likely to be associated with greater expression of the leptin receptor and NPY mRNAs than to changes in blood levels of leptin. Finally, this study provides evidence that chickens selected for high growth rates may be less sensitive or responsive to peripheral concentrations of leptin than chickens with low growth rates (layers), suggesting that the faster growth of broiler chicks may be related to a lessened responsiveness to anorexigenic factors.     

Response of young broiler chickens to chronic injection of recombinant-derived human insulin-like growth factor-I

The purpose of this study was to determine if exogenous insulin-like growth factor-I (IGF-I) would improve growth rate or body composition of young broiler chickens. Broiler cockerels were given a daily intramuscular (im) injection of sodium acetate buffer (buffer control), 100 or 200 μg recombinant-derived human IGF-I (rhIGF-I) per kg body weight from 11 to 24 days of age. Exogenous IGF-I did not affect the average daily gain, average daily feed consumption, or the gain-to-feed ratio of broiler chickens. Although daily injection of 200 μg/kg of rhIGF-I reduced (P<0.05) body ash content, there was no significant effect of IGF-I treatment on either body fat or protein content. Plasma GH levels were depressed (P<0.05) by chronic treatment with rhIGF-I. In contrast, plasma levels of T₃ and T₄ were not affected by rhIGF-I treatment. The half-life of rhIGF-I in plasma was determined at 25 days of age in naive control or chronically-injected chickens after a single intravenous dose of 50 μg rhIGF-I/kg. We found a single compartment, first-order disappearance pattern of rhIGF-I from chicken plasma. The half-life (t_1/2) of rhIGF-I in plasma was similar (t_1/2 = 32.5 min) for naive controls (injected once) or chronically-treated chickens which had received a daily injection of rhIGF-I (100 or 200 μg/kg) for 14 d. These data indicate that daily injection of IGF-I cannot be used to enhance growth performance or body composition of broiler chickens when given during the early growth period. The depression of plasma GH levels in rhIGF-I-injected chickens supports a negative-feedback role of IGF-I on pituitary GH secretion.     

Saline drinking water in broiler and Leghorn chicks and the effect in broilers of increasing levels and age at time of exposure

The purpose of this research was to assess the effect of increasing levels of salt and 5 g/L of salt (0.20% extra sodium) in the drinking water in broiler chickens at various ages up to five weeks of age and to compare the response of broiler chickens and White Leghorns to saline water (0.20% sodium). The effect was measured by the response of the right ventricle to pulmonary hypertension. The results indicated that broiler chickens under three weeks are more susceptible to saline water containing 0.20% sodium than those over three weeks of age, and that broilers given increasing levels of dietary salt may be more resistant to excess dietary salt than those that have had no previous exposure. The results also demonstrated that broiler chickens are more susceptible than White Leghorns to 0.20% extra dietary sodium in drinking water. We conclude that Leghorn chicks are more resistant to excess dietary sodium than broilers and that broilers become more resistant to saline water containing 0.20% sodium after three weeks of age.     

Changes in feed consumption and water intake among broiler chickens subjected to melatonin treatment during the hot-dry season

Tropical Animal Health and Production - The experiment was conducted to evaluate changes in feed consumption and water intake among broiler chickens subjected to melatonin treatment during the...     

Involvement of histaminergic and noradrenergic receptors in the oxytocin-induced food intake in neonatal meat-type chicks

Oxytocin neurons have a physiological role in food intake and energy balance. Several studies have shown that central histaminergic and adrenergic systems synapse on oxytocin neurons but there is no information for their interaction on food intake regulation in birds. The purpose of this study was to examine the effects of intracerebroventricular (ICV) injection of α-fluoromethylhistidine (α-FMH, histidine decarboxylase inhibitor), chlorpheniramine (histamine H1 receptors antagonist), famotidine (histamine H2 receptors antagonist), thioperamide (histamine H3 receptors antagonist), prazosin (α1 receptor antagonist), yohimbine (α2 receptor antagonist), metoprolol (β1 adrenergic receptor antagonist), ICI 118,551 (β2 adrenergic receptor antagonist) and SR59230R (β3 adrenergic receptor antagonist) on oxytocin-induced hypophagia in 3-h food-deprived (FD₃) neonatal broiler chicken. In Experiment 1, 3 h-fasted chicks were given an ICV injection of saline, α-FMH (250 nmol), oxytocin (10 μg) and co-injection of α-FMH + oxytocin. Experiments 2–9 were similar to experiment 1 except birds were injected with chlorpheniramine (300 nmol), famotidine (82 nmol), thioperamide (300 nmol), prazosin (10 nmol), yohimbine (13 nmol), metoprolol (24 nmol), ICI 118,551(5 nmol) and SR59230R (20 nmol) instead of α-FMH, respectively. After injection cumulative food intake was measured until 120 min post injection. According to the results, ICV injection of oxytocin significantly decreased food intake in broiler chickens (P < 0.001). ICV injection of α-FMH significantly attenuated hypophagic effect of oxytocin (P < 0.001). Also, co-injection of chlorpheniramine plus oxytocin significantly decreased the effect of oxytocin on food intake (P < 0.001). Co-administration of thioperamide and oxytocin significantly amplified hypophagic effect of oxytocin in chickens (P < 0.001). In addition, ICI 118,551 attenuated hypophagic effect of oxytocin (P < 0.001); while famotidine, prazosin, yohimbine, metoprolol and SR59230R had no effect on oxytocin- induced food intake in FD3 broiler chickens. These results suggest that the effect of oxytocin on food intake is probably mediated by histaminergic (via H1 and H3 receptors) and noradrenergic (via β2 receptors) systems in broiler chickens.     

Growth, food intake and energy balance of layer and broiler chickens offered glucose in the drinking water and the effect of dietary protein content

1. Four experiments were carried out to study the effect of offering a 91.5 g/l solution of glucose, compared to tap water, on fluid intake, food intake and growth of individually-caged immature chickens of both layer and broiler strains. 2. Male chicks of an egg-laying strain were offered glucose solution or tap water from 27 to 62 d after hatching. There was no effect of glucose on fluid intake but it depressed food intake (P less than 0.01) to give equal total energy intakes for each treatment. Body weight gain was reduced (P less than 0.001) and carcase fat content increased (P less than 0.001) by the glucose to yield no difference to total carcase energy. 3. When birds were placed in a respiration chamber for two 23-h periods there was no effect of treatment on outputs of energy as faeces + urine or as heat. 4. Male broilers were offered glucose solution or tap water with diets containing either 150 or 195 g protein/kg from 20 to 55 d after hatching. With the low-protein diet glucose depressed food intake (P less than 0.01) but total energy intake and carcase energy were not significantly affected. With the high-protein diet glucose did not depress food intake but increased total energy intake and total body fat. 5. Layer and broiler chicks were offered either a choice of the low- and high-protein diets or a single diet intermediate in protein content, with glucose solution or tap water. With broilers total food intake was depressed by glucose, mainly by a reduced intake of the low-protein diet. Intake of neither diet by the layer chicks was significantly affected by glucose. 6. It is concluded that provision of extra energy in glucose solution depresses food intake when the resultant energy:protein ratio becomes limiting. With a higher protein diet, or with birds having lower protein requirements, glucose solution does not depress food intake and increased fat deposition occurs.     

钠水平及种类对肉鸡生长性能、胴体性状及血清矿物质水平的影响

文章旨在评估日粮钠水平及种类对肉鸡生长性能、胴体性状及血清矿物质水平的影响。试验选择平均初始体重一致的白羽肉仔鸡832只,随机分为8组,每组4个重复,每个重复26只鸡。试验日粮采用4×2因子设计,即日粮钠水平分别为1.5、2.4、3.3和4.2 g/kg,以小苏打和硫酸钠两种形式添加,试验共进行42 d。结果:1~10 d肉鸡的增重和采食量受钠盐水平及钠盐水平与种类交互作用的显著影响(P<0.05),在1~10 d时,硫酸钠组日增重和采食量最高(P<0.05)。同时,在整个试验期间(1~42 d),2.4 g/kg硫酸钠显著改善了增重(P<0.05)。随着钠水平的升高,血液pH表现为显著升高(P<0.05),硫酸钠组血液pH显著高于小苏打组(P<0.05),硫酸钠组腹脂占比较小苏打组显著提高2.23%(P<0.05)。4.2 g/kg钠水平组血清钠和钙浓度最高(P<0.05),3.3 g/kg钠水平组血清钾、氯和镁浓度最高(P<0.05)。与小苏打组相比,硫酸钠组血清钾水平显著降低0.33%(P<0.05),而血清钙浓度显著提高9.2%(P<0.05)。结论:日粮中钠以硫酸钠的形式添加2.4~3.3 g/kg可改善1~10 d肉鸡的生长性能,而在33~42 d时降低日粮钠水平可以使肉鸡获得最大的增重和采食量。     

壳寡糖与屎肠球菌对肉仔鸡生长性能、免疫功能及肠道短链脂肪酸含量的影响

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。