Change in growth performance and liver function enzymes of broiler chickens challenged with infectious bursal disease virus to dietary supplementation of methionine and threonine

Problem statement: The aim of this study was to verify the effects of methionine and threonine supplementations higher than the NRC recommendation on growth performance, liver function enzymes, blood parameters and immune tissues of broiler chickens challenged with infectious bursal disease. Approach: A total of 450 day-old male broiler chicks were assigned to nine groups. Chickens were fed by three graded levels of DL-methionine [NRC (M1), 2 times NRC (M2) and 3 times NRC (M3)] and three graded levels of L-threonine [NRC (T1), 2 times NRC (T2) and 3 times NRC (T3)] from day 1-42 of age. On day 28, all birds were challenged with a commercial live-IBDV vaccine. Results: Body Weight Gain (BWG) and Feed Intake (FI) and Feed Conversion Ratio (FCR) were significantly influenced by the dietary treatments in starter phase and either methionine or threonine at the highest levels significantly decreased BWG, FI and FCR in broiler chickens. A similar trend by methionine and threonine at the highest levels was noted on BWG and FI in grower phase. The highest level of threonine significantly increased spleen weight on day 28 (pre-challenge) and 14 days post challenge. At 14 days after challenge, dietary supplementation of methionine at NRC recommended level (M1) significantly increased the serum concentrations of Alanine Aminotransferase (ALT), aspartate Aminotransferase (AST) and Lactate Dehydrogenase (LDH). In the T3 group, the serum concentrations of AST and LDH were significantly decreased, whereas the serum uric acid concentration was significantly increased. Conclusion/Recommendations: In conclusion, our data suggest that the methionine and threonine requirement of male broiler chicks is higher for growth performance than was suggested by the last NRC committee and liver function enzymes results showed that methionine and threonine supplementation three times higher than NRC requirements in broiler chickens has not toxic potential

Omega-3 polyunsaturated fatty acids enrichment alters performance and immune response in infectious bursal disease challenged broilers.

Background Infectious bursal disease (IBD) results in economic loss due to mortality, reduction in production efficiency and increasing the usage of antibiotics. This study was carried out to investigate the modulatory roles of dietary n-3 polyunsaturated fatty acids (PUFA) enrichment in immune response and performance of IBD challenged broiler chickens. Methods A total of 300 day old male broiler chicks were assigned to four dietary n-3 PUFA ascending levels as the treatment groups (T1: 0.5; T2: 8.0; T3: 11.5; T4: 16.5) using combinations of tuna oil and sunflower oil. All diets were isocaloric and isonitrogenous. On day 28, all birds were challenged with IBD virus. Antibody titer, cytokine production, bursa lesion pre and post-challenge and lymphoid organ weight were recorded. Results On d 42 the highest body weight was observed in the T2 and T3 and the lowest in T4 chickens. Feed conversion ratio of the T2 broilers was significantly better than the other groups. Although productive parameters were not responded to the dietary n-3 PUFA in a dose-dependent manner, spleen weight, IBD and Newcastle disease antibody titers and IL-2 and IFN-γ concentrations were constantly elevated by n-3 PUFA enrichment. Conclusions Dietary n-3 PUFA enrichment may improve the immune response and IBD resistance, but the optimum performance does not coincide with the optimum immune response. It seems that dietary n-3 PUFA modulates the broiler chicken performance and immune response in a dose-dependent manner. Thus, a moderate level of dietary n-3 PUFA enrichment may help to put together the efficiency of performance and relative immune response enhancement in broiler chickens

Oxidative stability of polyunsaturated fatty acids of n-3 designer eggs under different cooking methods

Variation in the extent of cooking time, temperature and heating source may greatly affect the polyunsaturated fatty acid (PUFA) double bond stability in eggs. A study was carried out to determine the oxidative stability of PUFA content of designer eggs subjected to different cooking methods. A total of 160 eggs of 4 commercial brands were obtained: A: conventional, B: DHA Gold™, C: LTK™, and D: Safegg™, and equally and randomly assigned to 4 cooking methods: (i) no cooking, (ii) boiling, (iii) frying, and (iv) microwaving. The results showed that brand and cooking method significantly influenced the PUFA content in the eggs. B had the highest n-3 and n-6 PUFA contents, and the lowest n-6/n-3 PUFA ratio compared to brands A, B, and D. The brand B had the lowest malondialdehyde (MDA) concentration compared to other brands. All methods of cooking increased MDA content (P0.05). In conclusion, boiling appeared to be the most and microwaving the least suitable method of cooking for eggs, as measured by PUFA and MDA content

Influence of selected essential amino acid and fatty acid supplementation on growth performance and immune response of broiler chickens challenged with infectious bursal disease virus

Products of poultry are now understood to be vulnerable to contagious diseases and are indicated to affect global industries. According to the research-based evidences shows that infectious bursal diseases (IBD) play a major role in economic losses due to reduced production efficiency, mortality and also the increased usage of antibiotics and chemicals to fight against infections which is a main concern for human health. Therefore, minimizing its impact is an important policy with different strategically approaches for success in the poultry industry. Nutrition is known as a strategy to control immunodeficiency. It is suggested that essential amino acids and fatty acids as immunostimulants are important for animal health. A series of experiments were conducted to examine the effects of essential amino acids and fatty acids as growth and health promotes in broiler chickens challenged by IBD virus. Experiment I was conducted to examine the effects of dietary methionine and threonine levels higher than the National Research Council (NRC) recommendation on growth performance and immune responses of broiler chickens challenged with IBDV. A total of 450 day-old male broiler chicks (Cobb) were housed in 45 pens of 10 birds each until day 42. The dietary treatments were three levels of methionine in the form of DL-methionine; at recommended (M1), double (M2) and triple (M3) NRC levels and three levels of threonine in the form of L-threonine at recommended (T1), double (T2) and triple (T3) NRC levels. There was significant decline in body weight and feed intake in birds subjected to the highest level of threonine and methionine but highest antibody titers and also the lowest lesion score were obtained in broilers receiving M2T3 and M3T3. Performance and immune responses of chickens fed with two folds of methionine (M2T1) were significantly (P<0.05)better than other treatment. The results obtained in the present study indicated that threonine and methionine requirements of broilers based on the recommendations of NRC did not give the maximum response. Experiment II was conducted to examine the effects of tuna fish oil and sunflower oil as sources of n-3 and n-6 PUFA on growth performances, fatty acid profiles and immune responses to IBDV challenged broiler chickens. Commencing from day one, five replicate pens of 15 one-day-Cobb male chicks each were assigned to one of the five dietary treatments, giving a total of 25 pens for 42 days. The dietary treatments were: 1) Basal diet (NRC) (C), (2) Basal diet containing 5.5% tuna oil + 0.5% sunflower oil (VL), 3) Basal diet containing 4% tuna oil + 2% sunflower oil (L), 4) Basal diet containing 2.5% Tuna oil + 3.5% sunflower oil (H) and 5) Basal diet containing 1.5% tuna oil + 4.5% sunflower oil (VH). The lowest feed conversion ratio of 1.94 (P<0.05) was observed in birds treated with H group. The birds fed VH group had lowest level of Interferon-gamma (IFN-) at 2 d post challenge ((P<0.05). The increase in n-3 PUFA levels significantly (P<0.05) tended to enhance Interlukin-2 (IL-2) as well as antibody titers production in IBDV challenged broiler chickens. Therefore, an ideal fatty acid profile should be maintained in the diet to improve the broiler chickens’ immune system. Experiment III was conducted to examine the response of IBDV challenged broiler chickens receiving different dietary ratios of n-6 to n-3 PUFA and supplementation of methionine on performance and immunity. A total of 350 one-day-old male broiler chicks (Cobb 500) were assigned to one of the six dietary treatments, giving a total of 35 cages. There were three ratio of n-6: n-3 PUFA [(45 (N1), 1.1 (N2) and 4.19 (N3)] and two levels of methionine in the form of DL-methionine [NRC (M1), 2 times NRC (M2)]. The birds aged 0-21 days were fed diets containing graded concentrations of methionine (0.25 and 0.80% of diet) similarly graded concentrations of methionine (0.23% and 0.74% of diet) to birds aged 22-42 days. Therefore, six dietary treatments were compared: 1) Basal diet based on NRC recommendation (M1N1), 2) Basal diet containing methionine 2 fold higher than NRC (M2N1), 3) Basal diet containing 5.5% tuna oil + 0.5% sunflower oil (M1N2), 4) Basal diet containing 2.5% tuna oil + 3.5% sunflower oil (M1N3), 5) Combination of diet 2 and 3 (M2N2) and 6) Combination of diet 2 and 4 (M2N3). A second control group served as IBDV-unchallenged group (CON) in this study. Prechallenge performance data indicates that body weight gain and feed conversion ratios significantly affected by the interaction between the methionine levels and n- 6: n-3 PUFA ratios. A mean body weight gain of 1411 g was highest at weeks 4 in birds treated with M2N3 group with an improved feed conversion ratio of 1.48 at pre challenged period. However, there was no any interaction between methionine and n-6: n-3 PUFA in broilers subjected to immunological challenge (P < 0.05). An antibody titer of 4.15 ng/ml and 4.04 ng/ml was significantly (P < 0.05) higher in birds fed a low ratio of n-6: n-3 PUFA (N2) than the other groups at 7 and 14 days after challenge. When methionine × n-6: n-3 PUFA ratio interaction was significant,the IL-2 level of M1N2 and INF- level of M2N1 were higher than other groups on 2 days and 7 days post-challenged, respectively. On d 28, serum cholesterol levels were significantly lowered (2.5mmo/L) in the birds treated with N2M1 (P<0.05). A significant improvement (P<0.05) in lesion score was observed in N2,N3 group on 7 days post-challenged and M2 group on 14 days post-challenged (P<0.05). Therefore, this study emphasizes those changes induced by the amount of n-6: n-3 fatty acid ratio may be supplied to the human diet as a result of consuming a portion of fat-modified chicken meat. In conclusion, current studies demonstrated that increasing the dietary methionine level up to two-fold of NRC (1994) standards is required to achieve adequate growth, feed conversion ratio and optimal immunity in IBD challenged broiler chicken. Dietary n-3 PUFA enrichment may improve the immune response and IBD resistance, but the optimum performance does not coincide with the optimum immune response. It seems that dietary n-3 PUFA modulates the broiler chicken performance and immune response in a dose-dependent manner. Thus, a moderate level of dietary n-3 PUFA enrichment may help to put together the efficiency of performance and relative immune response enhancement in broiler chickens.Further, although there was no interaction between high level of methionine and ratio of n-6:n-3 PUFA for performance parameters, humeral immunity and lesion score of bursa in broilers subjected to immunological challenge, the individual roles of n-6:n-3 PUFA ratio and methionine on bursa lesion reduction and/or antibody production are documented. Therefore, a balanced intake of both n-6 and n-3 fatty acid combined with methionine supplementation have the potential to promote performance and improve the broiler chicken immune system. Moreover, supplementation of fish oil in broiler diet may be considered as a functional practice to produce n-3 PUFA enriched meat with optimum n-6:n-3 PUFA ratios with regards to human health

Responses of performance and differential leukocyte count to methionine and threonine supplementations on broiler chickens challenged with infectious bursal disease in tropical condition

The aim of this study was to find the effect of methionine and threonine supplementations higher than the NRC recommendation on growth performance and white blood cell differentiation of broiler chickens challenged with infectious bursal disease. A total of 450 day-old male broiler chicks were assigned to nine groups. Chickens were fed by three graded levels of DL- methionine [NRC (M1), 2 times NRC (M2) and 3 times NRC (M3)] and three graded levels of L-threonine [NRC (T1), 2 times NRC (T2) and 3 times NRC (T3)] from day 1-42 of age. On day 28, all birds were challenged with a commercial live-IBDV vaccine. Body Weight Gain (BWG) and Feed Intake (FI) and Feed Conversion Ratio (FCR) were significantly influenced by the dietary treatments before challenge and either methionine or threonine at the highest levels significantly decreased BWG, FI and FCR in broiler chickens. Birds were fed with M3T3 had the lowest body weight gain after challenge. Supplementation of two times methionine and threonine (M2T2) to the diet decreased peripheral blood heterophils and increased lymphocytes and H/L ratio on day 28. On day 42, complete white blood cell tended to increase with increasing level of methionine supplementation. Threonine did not affect peripheral blood differential leukocyte count of broiler chickens. In conclusion, our data suggest that the methionine and threonine requirement of male broiler chicks is higher for growth performance than was suggested by the last NRC committee and methionine and threonine higher than NRC requirements in tropical condition can ameliorate the negative effects of heat stress

Functional alteration of breast muscle fatty acid profile by manipulation of dietary n-6:n-3 ratios in broiler chickens

Breast muscle fatty acid (FA) profile was studied in broiler chickens fed at different levels of n-6:n-3 polyunsaturated fatty acid (PUFA) ratios in 4 treatment groups; very high level of n-6:n-3 ratios (VH), high level of n-6:n-3 ratios (H), low level of n-6:n-3ratios (L), very low level of n-6:n-3 ratios (VL) and control, respectively. All the birds were slaughtered at 42 days of age and breast muscle were collected. FA profile of breast muscles was determined by gas liquid chromatography. Increased levels of fish oil significantly (P < 0.05) increased the long chain PUFA (LC-PUFA) n-3level, mainly because of the docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) content in the VL and L groups. n-6: n-3 ratios were effectively changed by the experimental diets. The LC- PUFA n-3 content of the VL and L groups of the breast muscle was significantly (P < 0.05) lower than in the VH, H and control groups. In conclusion, an increase in PUFAs n-3 associated with the dietary supplementation of fish oil maybe consider as a functional approach to elevate the nutritional value of chicken meat with regards to human nutrition

The effect of methionine and threonine supplementations on immune responses of broiler chickens challenged with infectious bursal disease

Problem statement: The aim of this study was conducted to determine the effects of supplementing methionine and threonine higher than the National Research Council (NRC) recommendation in the diets on immune responses of broiler chickens challenged with Infectious Bursal Disease (IBD). Approach: A total of 450 day-old male broiler chicks were assigned to one of the nine dietary treatments. Three levels of methionine (NRC (M1), 2 times NRC (M2) and 3 times NRC (M3)) and 3 levels of threonine (NRC (T1), 2 times NRC (T2) and 3 times NRC (T3)) were fed. On day 28, all birds were challenged with a commercial live-IBDV vaccine. Results: Antibody titer against IBD and ND were influenced by interaction of threonine and methionine. On 7 days after IBD challenge, ND antibody titer of the broilers receiving the highest level of methionine and threonine was significantly higher than that of other treatment groups. Lesion score of the bursa of the broilers receiving control diet was significantly the highest compared with the other treatments. Conclusion/Recommendations: The results obtained on the present study indicated that threonine and methionine requirements of broiler based on recommendation of NRC are not sufficient to meet the requirement of the new commercial poultry and commercial broiler companies under non-hygienic condition