Bursa Of Fabricius Weights Research Articles

Penthorum chinense Prush extract alleviates aflatoxin B1-induced toxicity, oxidative stress and apoptosis via mediating Nrf2 signaling pathway in the Bursa of Fabricius of broilers

Aflatoxin B1 (AFB1) is the primary mycotoxin that is responsible for the severe issues plaguing poultry farming. The study was aimed to explore the relevant pathways connected with immunity (inflammation, oxidative stress and apoptosis) in an AFB1-challenged chicken by using Penthorum chinense Prush extract (PCPE) in Bursa of Fabricius (BF) of broilers. A total one hundred and eighty day-old broilers were divided into six groups: Control, AFB1 (3 mg/kg feed), Yin-Chen-Hao Tang extract (YCHT) (10 ml/kg feed), and PCPE groups (low 1 g/kg, medium 2 g/kg, and high 3 g/kg PCPE/kg feed) respectively. The results showed that AFB1-challenged birds showed significant decrease in growth, BF weight index, serum antioxidant biomarkers and histopathological changes in BF tissues. The mRNA analysis showed that AFB1 upregulated the apoptosis associated genes (caspase-3, caspase-9, Bak, Bax and p53) and downregulated BCL-2. Additionally, AFB1 downregulated expression level of Nuclear Factor EF-2 (Nrf2) related genes (Nrf2, HO-1, NQO1 and GCLC) in the BF of broilers. The PCPE treatment showed positive impact on final weight gain, bursal index, and reversing of pathological changes in the BF of AFB1-challanged broilers. PCPE ameliorated oxidative stress generated by AFB1, as an increase in antioxidant enzyme activities, alleviated histopathological changes in BF, enhanced the Nrf2 expression levels and lowered the apoptosis gene expressions as compared to AFB1. The findings revealed that PCPE activated the Nrf2 pathway, antioxidant defense system and modulated the apoptosis in the BF of broiler chicken.

Resistant effects determination of Lactobacillus supplementation on broilers to consecutive hydrogen sulfide exposure

Hydrogen sulfide (H2S) is one of the most irritant gases present in rearing stalls that suppress broilers' healthy growth, which is seriously required an effective alleviation method. In this study, Lactobacillus was supplemented to investigate the alleviative effects on broilers reared under consecutive H2S exposure. A total of 180 healthy 1-day-old male AA broilers with similar body weight (40.8 ± 1.0 g) were randomly allotted into the control treatment (CON), the hydrogen sulfide treatment (H2S), and the Lactobacillus supplement under H2S exposure treatment (LAC) for a 42-d-long feeding process. Growth and carcass performances, immunity-related parameters, intestinal development and cecal microbial communities, and blood metabolites were measured. Results showed that Lactobacillus supplement significantly increased the body weight gain (BWG) while reduced the mortality rate, abdominal fat and bursa of fabricius weight during the whole rearing time compared with H2S treatment (P < 0.05). Serum LPS, IL-1β, IL-2, and IL-6 contents were observed significantly increased after H2S treatment while remarkably decreased after Lactobacillus supplementation(P < 0.05). Intestinal morphology results showed a significant higher in the development of ileum villus height (P < 0.05). Cecal microbiota results showed the bacterial composition was significantly altered after Lactobacillus supplement (P < 0.05). Specifically, Lactobacillus supplement significantly decreased the relative abundance of Faecalibacterium, while significantly proliferated the relative abundance of Lactobacillus, Bifidobacterium, Clostridium, and Campylobacter (P<0.05). Metabolic results indicated that Lactobacillus supplement may alleviate the harmful effects caused by H2S through regulating the pyrimidine metabolism, starch and sucrose metabolism, fructose and mannose degradation, and beta-alanine metabolism. In summary, Lactobacillus supplement effectively increased BWG and decreased mortality rate of broilers under H2S exposure by enhancing the body's immune capacity, proliferating beneficial microbes (e.g., Lactobacillus and Bifidobacterium), and regulating the physiological pyrimidine metabolism, starch and sucrose metabolism, and beta-alanine metabolism.

EFFECTS OF DIETARY NUCLEOTIDES SUPPLEMENTATION ON THE PERFOR-MANCE OF BROILER CHICKS

This study examined the effects of nucleotide supplementation on broiler chick growth performance, immunological response, carcass traits, meat quality, serum biochemical parameters, total antioxidant capacity, intestinal morphology, mortality rate, and economic efficiency measures of broiler chicks. A total of 180 one-day-old chicks (Ross 308) were distributed into 6 groups, each of which consisted of 30 chicks, and each group was divided into 3 replicates so that each replicate contained 10 chicks fed on six experimental diets as follows: basal diet without oil or nucleotide (T1), basal diet with 1% soybean oil and without nucleotide(T2), 50 grams nucleotide per 100-kilogram diet with different fat sources (no oil(T3), 1% soybean oil(T4), 1% linseed oil(T5) &amp;1% fish oil(T6) respectively during the experimental period (5 weeks). Growth performance parameters were detected per stage period. Four chicks from each replicate were used at the termination of the experiment for analysis of the above mentioned measurements. Results revealed that supplementation of nucleotide in diets of broiler chicks improved feed conversion ratio, carcass traits, intestinal morphology, serum biochemical parameters, immunological response, bursa of Fabricius weight, and the best ratios were observed in groups fed nucleotide in combination with fish and linseed oil. Also, there was an increased economic efficiency in the SBO fed group(T2) then group fed nucleotides in mix with linseed oil (T5) and control (T1). In comparison to the control groups (T1 &amp; T2), groups fed nucleotides and PUFA oil sources had significantly lower n-6: n-3 ratio in breast muscle, and mortality rate.

Effects of Capsaicin on Growth Performance, Meat Quality, Digestive Enzyme Activities, Intestinal Morphology, and Organ Indexes of Broilers.

This experiment was conducted to investigate the effects of capsaicin (CAP) on growth performance, meat quality, digestive enzyme activities, intestinal morphology, and organ indexes of broilers. A total of 256 one-day-old Arbor Acre male broilers were randomly allocated into four treatments with eight replicates of eight birds, feeding a basal diet (control group), a basal diet supplemented with 2, 4, and 6 mg/kg CAP for 42 d, respectively. The growth performance, digestive enzyme activities of intestinal contents, small intestinal morphology, and organ indexes were measured at 21 and 42 d. The meat quality traits of breast muscles were determined at 42 d. The results showed dietary 4 mg/kg CAP supplementation decreased (P < 0.05) the feed to gain ratio (F/G) in the grower phase (22–42 d) and overall (1–42 d) compared with the control group, and 2 mg/kg CAP group also decreased (P < 0.05) the F/G from 1 to 42 d. Dietary 4 mg/kg CAP supplementation decreased (P < 0.05) the drip loss at 48 h and the pH24h of breast muscles relative to the control group. Some digestive enzymes activities of jejunal and ileal contents were increased in the 2 and 4 mg/kg CAP groups compared with the control group both at 21 and 42 d. In addition, dietary 2 mg/kg CAP supplementation increased (P < 0.05) the relative weight of liver, jejunal villus height, villus width, and villous surface area at 21 d; The length of the jejunum segment and the relative weight of Bursa of Fabricius at 42 d in the 4 mg/kg CAP group were higher (P < 0.05) than the control group. In conclusion, dietary 2 or 4 mg/kg CAP supplementation decreased the F/G, improved meat quality, enhanced digestive enzyme activities, improved the jejunal development, and increased the relative liver and Bursa of Fabricius weight in broilers.

Effects of Propolis and Ginger on Broiler performance and Immune Organ Weight in Broilers

phytobiotics were introduced to poultry industries for enhancement of immunity and growth performance. The aim of this study was to assess the effect of propolis and ginger aqueous extract on body weight gain and immune-related organ weight. 100 one day old chicks were allocated into five groups; control, ginger-treated, propolis-treated, ginger/propolis-treated, and vaccinated untreated groups for 35 days. At the end of experiment, the body weight and immune-related organ weight were recorded. The result showed that the treated groups with ginger, propolis, and ginger/propolis non significantly increased the body weight and the weight of spleen and thymus gland alongside with non-significant decrease in the bursa of fabricius weight. This study concluded that ginger and propolis could be considered as growth promoter used for enhancement of growth in broiler chickens.

Morphological characterization of spleen and bursa of Fabricius of Pekin ducks in selenium-deficient area

The study was aimed at examination of age-related morphology of spleen and bursa of Fabricius of Pekin ducks with a dietary selenium deficiency and its correction with an organic selenium additive. The experimental study was carried out in 85 day-old ducks divided into two groups, control group and test group, 40 ducks per group, the experiment lasted for 120 days. Control group was fed with standard mixed feed for meat-type poultry. The test group of ducks was fed with the feed supplemented with DAFS-25k organic selenium additive, 1.3 mg/kg of feed, that fully compensated selenium deficiency. The study showed that the dynamics of absolute body weights and relative weight gains in control and test groups correlated to the general biological pattern – increase in absolute parameters and decrease in relative parameters were dependent on age. Therewith, maximum relative weight gain intensity was reported at the age of 15 days and maximum increase in relative spleen and bursa of Fabricius weights was reported in at the age of 30 days. Weight gain parameter drastically decreased on day 75 and remained low up to the age of 120 days. Changes in the relative spleen and bursa of Fabricius weights were non-linear throughout the study. Therewith, in ducks of all ages tested spleen parameters remained approximately at the same level but bursa of Fabricius parameters changed – relative weight of bursa of Fabricius decreased by the age of 45 days and then increased again by the age of 75 days. Relative weight gains and relative spleen weights of ducklings in test group were higher than that ones of ducklings in control group during the examined ontogenesis periods. The opposite pattern was observed for bursa of Fabricius: the above-mentioned parameters in test group were lower than that ones in control group. It was concluded that organic selenium additive had a positive effect on development of the immune system organs and reduced the stress factor impact on duckling organism.

Effect of different levels of bioplex manganese along with probiotics and multi-enzymes on performance and immune system indices of broilers.

To investigate the effect of different levels of bioplex manganese along with probiotics and multi‐enzymes on the performance and immune system of broilers, 640 one‐day‐old male chicks of the Ross 308 strain were reared and the data analysed in a 4 × 2 × 2 factorial experiment with four levels of bioplex manganese (0, 60, 72 and 84 mg per kg of diet), two levels of Parsilact probiotic (0 and 200 mg per kg of diet) and two levels of Combo multi‐enzyme (0 and 1,000 mg per kg of diet) in a completely randomized design with 16 experimental treatments, 4 replicates and 10 chickens per replicate during a period of 42 days. The results showed that the performance of the broiler chickens in the diets containing 72 and 84 mg bioplex manganese along with probiotics and multi‐enzymes had the greatest difference compared to the control (p < .05). Compared to the control with 0 mg/kg manganese; the bursa of Fabricius weight was greater in chickens fed diets containing additional manganese (p < .05). The concentration of antibodies produced against Newcastle disease virus, as well as the concentrations of IgG, IgM and total immunoglobulins produced against SRBC, were highest in the group fed a diet containing 84 mg manganese along with probiotics and multi‐enzymes (p < .05). The results show combining additional manganese with probiotics and multi‐enzymes in chicken diets leads to better performance as well as a stronger immune system of chickens.

Effect of dietary raw and fermented sour cherry kernel (Prunus cerasus L.) on growth performance, carcass traits, and meat quality in broiler chickens

Sour cherry kernels are waste products of the fruit juice industry. Solid-state fermentation has great potential for recycling the agro-industrial residues. In the present study, the effect of raw sour cherry kernel (RC) and fermented sour cherry kernel (FC) by Aspergillus niger on growth performance, carcass traits and meat quality in broiler chickens was investigated. A total of 343 one-day-old male broilers (Ross 308) were randomly allocated to 7 treatments with 7 replicates for each treatment and 7 birds in each replicate. The chicks were fed on a basal diet (control) and basal diet supplemented with RC or FC at the 1, 2, and 4% level. Dietary RC improved (P < 0.001) the feed conversion ratio (FCR) at the 1% inclusion level although chicks fed 2 and 4% RC had lower (P < 0.01) body weight (BW), body weight gain (BWG), and feed intake (FI) from day 1 to 42, compared with that of the birds in the control group. Dietary FC with 1% inclusion level increased (P ≤ 0.05) BWG from day 22 to 42 and also enhanced (P < 0.001) the FCR from day 1 to 42. However, 4% dietary FC had an adverse effect (P < 0.01) on BW, BWG, FI, and the FCR, compared with the control group. The bursa of Fabricius weight was raised (P < 0.01) as the supplemental FC level increased. Dietary RC and FC elevated gut weight (P < 0.01) and length (P ≤ 0.05). Broilers fed on 2% FC had a higher (P ≤ 0.05) ash level and a lower (P ≤ 0.05) b* value in thigh meat, compared with the 2% RC group. The results indicate that FC can be used in broiler nutrition up to 2% level although RC can be added to broiler diets up to 1% level without a detrimental effect on growth performance. Dietary inclusion of 1% RC or FC can be recommended due to the positive effects on broiler chickens.

Effect of Varying Proportions of Lignin and Cellulose Supplements on Immune Function and Lymphoid Organs of Layer Poultry (Gallus gallus).

To determine the benefits of different types or proportions of insoluble fiber components on growth and immunity, 4-week-old commercial layer pullets were fed supplements containing different proportions of purified lignin and cellulose or a commercial lignocellulose supplement. The 64 Hy-Line Brown pullets were provided basal diets supplemented with 1 g fiber per 100 g diet. The supplements included a commercial lignocellulose, Arbocel® RC fine (group A) with cellulose to lignin ratio of approximately 3:1, cellulose (group Ce), a 3:1 mixture of cellulose: lignin (group Ce3Lig1), and a 2:1 mixture of cellulose: lignin (group Ce2Lig1). After 3 weeks, innate immune function was measured in terms of heterophil phagocytosis and oxidative burst (n=8). After 4 weeks, ex vivo stimulated lymphocyte proliferation was determined for assessment of cell-mediated immune function (n=7). All pullets were killed at 9 weeks of age and lymphoid organs were weighed (n=16) and small intestinal Peyer's patches (PP) were measured (n=8). Pullets in both A and Ce3Lig1 groups had heavier (P<0.05) body and bursa of Fabricius weights. The number of PP in group A was higher (P<0.05) than in group Ce. The percentage of heterophil phagocytosis in A and Ce3Lig1 groups were higher (P<0.05) than in group Ce, and oxidative burst of group A was higher (P<0.05) than that of group Ce. Addition of 1% Arbocel or 1% Ce3Lig1 to the diet of layer pullets from 4 to 9 weeks of age significantly improved their growth and innate immune function compared to group Ce. This suggests that lignin either modulates the effect of cellulose or has specific mechanisms of action in the gut that improves growth and immunity. The proportion of lignin to cellulose may also be important for growth and immune function.

Characterization of Immune and Enteric Systems of Broilers after Imunosupression with Dexamethasone

Background: Bursa of Fabricius (BF) and the thymus are primary lymphoid organs of poultry and play a major role in avian immunity. Enteric system is also involved in immunity. Several pathologic conditions directly impact BF and thymus size, and also affect intestinal parameters. Besides, there are several immune system depressor agents which affect birds. The selection of glucocorticoid as inducer of immunosuppression is applied in many experiments; however there are few studies that are applied to the reality in the field. In this context, the aim of this study was to evaluate the effects of dexamethasone as an inducer of immunosuppression on lymphoid organs and microscopic structures of the jejunum.Materials, Methods &amp; Results: One-day-old chicks were used as a control group (n = 8) and the treated group (n = 25) received intramuscular dexamethasone on 21, 23, 24 and 26 day-old. Control birds and treated birds were euthanized 8, 16, 24, 32 and 40 h after inoculation; four control birds and six treated birds were euthanized on the eighth day after the last inoculation. Thymus, BF and jejunum were collected during the necropsy. The selected organs were processed, stained with hematoxylin and eosin and photographed. The BF and thymus cuts were evaluated by three histopathologists to determine the depletion score. Ten villi of each jejunum were evaluated for width and length of villi, depth crypt, microvillus length, enterocyte length of each villus, and wall thickness. Treated birds presented a mean weight lower than control group during all the experiment. The mean weight and the relative weight of the BF and thymus of control birds were significantly higher than treated ones. The lymphocyte depletion in BF and thymus scores differed significantly between groups, being higher in the group challenged with dexamethasone. There were no significant differences between groups for depth of crypt, height of core and height of microvilli. The intestines of the control group had higher mean values for length of villi, width of villi, height of enterocyte and thickness of wall. Significant correlation between weight of thymus and weight of BF, between weight of thymus and weight of bird and between weight of BF and bird weight were found.Discussion: Easy administration, low cost and the absence of suffering during inoculation make the use of glucocorticoids more advantageous to mimic immunosupression in poultry. Treatment with dexamethasone interfered directly in the weight of the birds. Evaluation of immune response of birds can be performed by the ratio of the BF weight in relation to the weight of the bird, as observed in the present study. The relative weight of the BF of untreated animals varied at all ages between 0.21% and 0.29%. It was also observed that the relative weight of BF and thymus in immunosuppressed birds tended to increase according to the end of the treatment. Depletion scores were higher in thymus, suggesting that glucocorticoid promoted more harmful effects on this organ. Dexamethasone had negative influence on length of villus, once mean value was 13% lower than those of control group. Width of villus and height of enterocyte core of treatment group were lower than those observed in control animals. Coefficient of determination greater than 70% was observed for almost all established relationships, except for the length of villi and weight of the thymus. Administration of dexamethasone promotes significant and negative effects on the gain of weight, length of villi, width of villi and height of enterocytes. These finding are useful for future experiments with controlled immunosuppression induction, once it provides significant information of the secondary effects of glucocorticoids administration in poultry.

Effects of dietary inclusion level of a mixture of probiotic cultures and enzymes on broiler chickens immunity response.

The current study was conducted to analyse the effect of a mixture of probiotic cultures and enzymes (Probio Enzyme, XVET GmbH, Germany) on the immune response and weight of central lymphoid organs and liver in broilers. A total of 270 male chickens were randomly divided into nine groups, with three replicates of 10 birds each. Treatment groups were fed for either 22 or 42days with different levels of Probio Enzyme 250, 500, 750 and 1000g/ton, whereas the control group fed a basal diet without Probio Enzyme. To analyse the effects of dietary supplementation on broilers humoral immune response, the antibodies titres for avian influenza (AI) and Newcastle disease virus (NDV) and to the sheep red blood cells (SRBC) challenge were assayed in birds from each experimental unit, along with the assessment of the weight of the main lymphoid organs and liver. The addition of the Probio Enzyme mixture did not significantly affect the titres of the antibodies against AI and NDV at day 42, despite the wide individual variation observed specially on the antibody titres at day 33. Treatments affected the production of IgG after the second challenge with SRBC (P=0.003), which was transposed to the correspondent total Ig titres (P=0.044). Conversely, a lower birds' body weight (BW) was found in the majority of treated groups compared to control (P=0.031). The spleen was the only lymphoid organ showing differences in the absolute and relative weight (P=0.003 and P=0.001, respectively). No differences were found in thymus and Bursa of Fabricius weights. In conclusion, broilers treated with Probio Enzyme showed a satisfactory immune response compared with control, despite the wide variation found after the first vaccine challenge against AI. Moreover, the probiotic mixture dose and duration modulated differently the immune response and the spleen weight, unaffecting the central lymphoid organs weight.

Genomewide association study of immune traits in chicken F2 resource population.

Immune traits play pivotal roles in animal immune capacity development and disease resistance. Single nucleotide polymorphisms (SNPs) are common forms of genetic variations among individuals, which are thought to account for the majority of inherited phenotypic variations. In this study, we performed genomewide association, using the Illumina 60K SNP BeadChip studies to detect molecular markers and candidate genes associated with immune traits in an F2 population. Sixteen immune traits were measured. We identified 85 significant SNPs (p<2.98×10(-6) ) with 5% as the genomewide significance threshold, 380 SNPs of suggestive significance (p<5.96×10(-5) ) from simple model (general linear model, GLM) and 15 SNPs of suggestive significance (p<5.96×10(-5) ) from the compressed mixed linear model (MLM), which were also found in GLM (six significant SNPs and seven suggestive SNPs). Three significant SNPs (GGaluGA151406, Gga_rs14554319 and Gga_rs13593979) and candidate genes (LYRM4 and KTN1) were found to be associated with avian influenza antibody titres, and the first two SNPs are from the results of two-model analysis. For the immune organs, through the analysis of GLM, 19 SNPs were found to be significantly associated with the thymus weight, 61 SNPs were significantly associated with the bursa of Fabricius weight, six of which were located within a 34-Mb region (125846474-159649698bp) on chicken chromosome 1 (GGA1). A candidate region relevant to haematological traits from GLM was found in GGA4 and 9 loci were located on it. Three loci (GGaluGA348521, Gga_rs16098446 and GGaluGA348518) within 179kb (16286868-16466134bp) on GGAZ from GLM provided evidence that this genomic segment may be relevant to red blood cell volume distribution width (RDW). Our study provides a list of significant SNPs and candidate genes that will be valuable information for unveiling the underlying molecular mechanism of immune regulation.

The effects of environmental enrichment and transport stress on the weights of lymphoid organs, cell-mediated immune response, heterophil functions and antibody production in laying hens.

The effects of environmental enrichment and transport stress on the immune system were investigated in laying hens. A total of 48 1-day-old chickens were used, half of the chickens were reared in conventional cages (RCC) and the rest in enriched cages (REC). Transport stress was applied in the 17th week. Liver weight decreased, spleen and bursa of Fabricius weights, white blood cell count, CD4+ and CD8+ cell proportions increased due to the transport. Environmental enrichment significantly increased antibody production and tended to increase monocyte percentage and CD8+ cell proportion. The effect of transport on, heterophil (H) and lymphocyte (L) percentages was not significant in RCC chickens. While heterophil percentage and H:L ratio increased, lymphocyte percentage decreased in REC chickens subjected to transport. Transport stress increased heterophil functions both in REC and RCC chickens, but the increase was higher in REC hens than in RCC hens. In conclusion, although environmental enrichment did not neutralize the effect of transport on lymphoid organs, it activated the non-specific immune system, cellular and the humoral branches of the specific immune system by increasing heterophil functions, CD8+ cells and antibody production, respectively. Therefore, environmental enrichment suggested for improving animal welfare may also be beneficial to improve the immune system of birds exposed to stress.

Ammonia concentration and relative humidity in poultry houses affect the immune response of broilers.

To investigate the effect of ammonia (NH3) and humidity on the immune response of broilers, broilers were exposed to 30 or 70 mg/kg atmospheric NH3 for 21 days. Additionally, birds were exposed to 35, 60, and 85% relative humidity (RH). The relative weights of lymphoid organs, serum total protein, serum globulin, serum albumin, serum lysozyme, proliferation index of peripheral blood lymphocytes, and splenic cytokine gene expression were determined. Exposure to 70 mg/kg NH3 decreased the relative weight of the spleen during the experimental period, serum lysozyme concentration in the first and second weeks, and serum globulin concentration in the third week. The proliferation of peripheral blood lymphocytes was reduced. High levels of NH3 caused increase in IL-1β gene expression in the experimental period and IL-4 gene expression in the first week. Birds exposed to 85% RH had lower thymus and bursa of Fabricius weights in the third week and serum lysozyme concentration in the first week; IL-1β and IL-4 expressions were higher in the second and third weeks and first and second weeks, respectively, than in birds exposed to 60% RH. IL-4 expression was lower during the first week, and IL-1β expression was higher during the second week with 35% RH than with 60% RH. In conclusion, high NH3 level in the poultry house suppressed the immune response of broiler chickens. Neither high nor low RH benefited the immune response of broilers. Furthermore, there was an interactive effect between NH3 and RH on the immune response of broilers.

Extract and leaf powder effect of Artemisia annua on performance, cellular and humoral immunity in broilers

Summary The effects of methanolic extract and leaf powder of Artemisia annua were studied on performance, cellular and humoral immunity in 240 Cobb broiler chicks in a completely randomized design. Control group did not receive any treatment. The chicks in the second and third groups were fed with feed which contained 2000 and 4000 ppm plant extract in diet and in the groups 4, 5 and 6 chicks received 0.5, 1 and 1.5% of dietary Artemisia annua leaf powder, respectively. Daily feed intake, daily weight gain and feed conversion ratio (performance) were measured. Skin response to phytohemagglutinin-P (PHA-P) injected intradermally on day 16 was measured 24 and 48 h after injection. The birds were immunized with sheep red blood cells (SRBC) on days 8 and 22 of age and serum antibody levels produced in response to SRBC were measured on days 21, 28, 35 and 42. The weights of thymus and bursa of fabricius were also measured after slaughter. The results indicated that plant extract and leaf powder increased daily weight gain and reduced daily feed intake and feed conversion ratio (P<0.05). Plant extract and leaf powder increased cellular immunity on PHA-P injection after 24 and 48 h (P<0.05). Artemisia annua extract and leaf powder increased total anti-SRBC and IgG titer in experimental groups compared to control group (P<0.05). Thymus and bursa of fabricius weights were increased in treatment groups (P<0.05). It is concluded that Artemisia annua extract and leaf powder increases performance, cellular and humoral immunity of broilers.

Immunomodulation in gut-associated lymphoid tissue of neonatal chicks by immunobiotic diets

Developmental changes in immunocompetent cells of the gut during the first week posthatch were determined in broiler chicks fed immunobiotic lactic acid bacteria in the form of Lactobacillus jensenii TL2937-, Lactobacillus gasseri JCM1131(T)-, Lactobacillus delbrueckii ssp. bulgaricus NIAIB6-, or L. gasseri TL2919-supplemented diets. The relative weights of spleen and bursa of Fabricius in chicks fed the immunobiotic diets were slightly higher than the control valued at 1 and 3 d of age, with the exception of spleen weight in the L. gasseri JCM1131(T) at 3 d of age, the bursa of Fabricius weight in the L. gasseri JCM1131(T) at 1 and 3 d of age, and bursa of Fabricius weight in the L. gasseri TL2919 group at 1 d of age. There were no significant differences in body and liver weights among the treatments. When chicks were fed the L. jensenii TL2937- or L. gasseri TL2919-supplemented diets, expression of T cell-related mRNA [cluster of differentiation 3 (CD3), interleukin-2 (IL-2), and interferon-gamma (IFN-gamma)] in the foregut was significantly higher than that of control chicks at 3 or 7 d of age. Expression levels of toll-like receptor (TLR) mRNA tended to increase in the foregut of chicks fed the immunobiotic diets, except for the L. delbrueckii ssp. bulgaricus NIAIB6, compared with expression levels in control chicks. The Bu-1 mRNA expression levels in the bursa of Fabricius were not affected by the supplementations with immunobiotic lactic acid bacteria. These results show that immunobiotics, particularly L. gasseri TL2919, might be useful as immunomodulators to stimulate the gut-associated immune system in neonatal chicks, and thereby protect them from disease without decreasing growth performance as a possible substitution of antibiotics.

Daily variations in response of certain immunity indices to prolactin in White Leghorn chickens.

The purpose of this experiment was to elucidate whether the effect of exogenous prolactin (PRL) on immunity parameters of White Leghorn chickens varies during the day. The experiment was carried out on cockerels kept after hatching during 6 weeks under L:D = 12:12 conditions. During 5 consecutive days cockerels were injected with bovine PRL (150 micrograms per bird daily) or its solvent at different time points, i.e., at 0, 4, 8 or 12 HALO (Hours After Light Onset). The birds were sacrificed 24 hours after the last injection at the same time point when the injections were given. It was found that given at 4 HALO prolactin raised, whereas at 8 HALO it decreased the peripheral lymphocyte number. PRL had no effect on granulocyte number, natural anti-rabbit red blood cells (anti-RRBC) agglutinin titre and serum lysozyme activity. Administered at 0 and 12 HALO PRL tended to decrease the thymus and bursa of Fabricius weight. This different PRL effect on peripheral lymphocytes in chickens during the circadian period may be one of the causes of varying effect of this hormone on immunity (stimulatory or suppressive) described in literature. The role of PRL in regulation of immunity is discussed in relation to the possibility of PRL receptors occurrence on chickens lymphocytes.

Effects of Anti-Bursin Monoclonal Antibody on Immunosuppression in the Duck (Cherry Valley Duck)

To study the immunologic function of bursin, we analyzed the effects of anti-bursin monoclonal antibody (mAb) on the immunosuppression in ducks (Cherry Valley duck) by injecting various doses of the anti-bursin mAb into 13-d duck embryos. After hatch, cell-mediated immune activity and humoral responses were studied using lymphocyte proliferation test, tube agglutination test, and indirect enzyme-linked immunosorbent assay to detect anti-Escherichia coli antibodies and antibodies to Riemerella anatipestifer, respectively. Simultaneously, relative weights (BW-adjusted) of bursa of Fabricius (BF), spleen, and thymus were determined. Additionally, the morphology of BF, spleen, and thymus was examined at various ages using conventional histology. Follicle morphology of BF was analyzed by image analysis. The results indicated that anti-bursin mAb markedly decreased duck lymphocyte proliferation, the antibody-producing ability to bacteria, as well as the relative BF weight. Moreover, the anti-bursin mAb hindered the development of BF follicles.

MYCOTOX® and aflatoxicosis in quails

1. This study was to evaluate the toxic effects of aflatoxin (AF) on growth performance of quail, and to determine the preventive efficacy of MYCOTOX® (oxicinol, tymol, micronised yeast). 2. One hundred and eighty 1-d-old quail (Coturnix coturnix japonica) of both sexes were weighed and randomly divided into 4 experimental groups each with 5 replicates of 9 birds. 3. There were 4 dietary treatments: (1) control with 0 mg AF/kg diet and 0% MYCOTOX®; (2) 0 mg AF/kg diet and 0·5% MYCOTOX®; (3) 2·5 mg AF/kg diet and 0% MYCOTOX®; (4) 2·5 mg AF/kg diet plus 0·5% MYCOTOX®. The chicks were maintained on these treatments to 3 weeks of age. Quail consumed the diets and water ad libitum. 4. Body weight (BW) gains in groups receiving AF alone were the lowest at all periods. Feed intake was lowest in the group consuming the AF diet. The addition of MYCOTOX® to the AF diet did not prevent or reduce the toxic effects of AF on feed intake at any time period. Feeding diets containing MYCOTOX® alone did not change feed intake significantly. With the exception of the 1 to 7 d period, feed conversion of chicks fed the AF diet was similar to those of the other experimental groups. 5. Bursa of Fabricius weight decreased, whereas the relative weights of liver, kidney and spleen increased in quail consuming diets containing AF and AF plus MYCOTOX®. Liver colour was normal in the control and MYCOTOX® alone group, but was lighter in groups fed AF. 6. The results indicated that MYCOTOX® was not effective in preventing the deleterious effects of AF.

Gumboro disease: evaluation of serological and anatomopathological responses in vaccinated broiler chickens challenged with very virulent virus strain

This paper describes the effects of a strong type of vaccine - Moulthrop G603 o and an intermediate-plus type of vaccine - 228E o in meat-type chickens challenged with a very virulent strain of infectious bursal disease virus (vvIBDV). Blood samples and bursa of Fabricius were taken weekly up to 42 days of age. It was concluded that bursa of Fabricius weight, bursa weight:body weight ratio, body weight and antibody titer evaluated before and after challenge with vvIBDV were not enough to consistently and conclusively differentiate or estimate the protection given by vaccination. Quantitative evaluation of injury intensity and the number of altered lymphoid follicles revealed that Moulthrop G603 caused moderate microscopic lesions in one out of seven birds vaccinated at 14 days of age, while 228E vaccine did not induce IBD-typical microscopic lesions in the bursa of Fabricius. Good protection against bursal microscopic lesions was obtained when a strong type of vaccine was used before challenging with vvIBDV. It was concluded that quantitative evaluation of microscopic lesions might be useful to measure the injury induced by vaccinal IBDV, as well as the level of protection and/or immunosuppression induced by IBDV challenge in vaccinated and non-vaccinated chickens.