Journal of Animal Production, Print ISSN: 2008-6776., Online ISSN: 2382-994X

Abstract Objective: The suckling calf is particularly susceptible to digestive and respiratory disease because of its immature immune system and increased mortality, making it one of the major challenges of the livestock industry. The nutritional strategy to enhance the performance of suckling calves by supplementing their diet with feed additives, such as probiotic and biochar, was evaluated in this study. Method: Twenty-eight female newborn Holstein calves (41.2 ± 3.8 kg) were used in a 2×2 factorial arrangement within a completely randomized design over a 70‑day experimental period. Experimental treatments were as follows:1- basal diet without additive (control), 2- basal diet with 2 g/day of probiotic, 3- basal diet with 1% biochar and 4- basal diet with 2 g/day of probiotic plus 1% biochar. The basal diet was formulated with a 10:90 forage-to-concentrate ratio to meet nutrient requirements. Water and starter feed were provided ad libitum throughout the experiment. Feed intake was recorded daily, body weight and skeletal growth changes were assessed every two weeks. Blood samples were collected on days 0 (birth time), 35 and 70, and fecal samples were collected to evaluate diet digestibility in the last week of the experiment from all calves. All calves were observed for three days at the end of the experiment to record their feeding behaviors (standing, lying, eating, and ruminating) and non-feeding behaviors (licking, sucking, and chewing on environmental objects). Results: Results indicated that calves that were supplemented with dietary biochar had significantly higher starter feed intake and weaning body weight compared with the non‑biochar groups (P<0.05). Wither height, hip height and abdominal circumference of the calves also increased with biochar supplementation (P<0.05). Concurrent supplementation with probiotic and biochar (treatment 4) further enhanced wither height and hip height (P<0.05). probiotic and biochar supplementation improved apparent digestibility of organic matter and crude protein (P<0.05), respectively, whereas the digestibility of other nutrients was unaffected by experimental treatments. Biochar supplementation also increased blood glucose concentration (P<0.05). Dietary treatments did not significantly affec any of the feeding behaviors. Interaction effects of probiotic and biochar were not significant on any of the parameters measured in this study. Conclusions: Overall, dietary supplementation with biochar, either alone or in combination with probiotic, showed significant positiv effects on performance, skeletal growth indices, and digestibility of nutrients in suckling calves, suggesting that biochar may be used as a functional feed additive to support early-life health and productivity.

Abstract Objective: During the first week of life, body weight increases 2- to 3-fold, and there are significant changes in the weight and morphology of the gut and muscles. Gastrointestinal development is particularly important in early chick growth and delayed feeding during the first few days of life reduces final BW and probably affects gut health and immune function. Probiotics are live microbial feed additives and can be considereda functional nutritional approach, whereby adequate amounts of live beneficial microorganisms are administered to establish a healthy microbial environment and improved intestinal function in young chicks, resulting in stimulation of mucosal immunity, pathogen inhibition, improvedperformance, and modulation of intestinal microflora of young or stressed broilers. As such, probiotic seems to influence broiler growth performance and intestinal growth under late feeding challenge. Method: The objective of this experiment was to investigate the effect of probiotic levels on performance, blood metabolites and small intestine morphology of broiler chickens subjected to late feeding challenge (LFC). The experiment was conducted using a completely randomized design and a 3×3 factorial arrangement with 3 levels of probiotic (0, 0.2 and 0.4 g/kg feed) and 3 LFD time (0-, 12- and 24-h), 450 Ross-308 broiler chickens (one-d-old, mixed sexes) were allocated to 9 treatments, 5 replicates and 10 birds in each replicate. Results: The broiler chickens fed greater level of probiotics and immediately access to feed had the highest BW and BWG and those fed with 24h LFC and greater level of probiotic had the lowest BW at the end of the starter period; and at the end of the experiment, broiler chickens fed 0.2 g/kg probiotics with 12h LFC and those fed greater level of probiotics and immediately access to feed had the lowest FI, BW and BWG (P < 0.05). LFC time had no significant effect on the distribution parameters of chickens at 10d age and carcass parameters at 42d age. Broiler chickens fed 0.4 g/kg probiotics with 12- and 24h LFC had the lowest triglyceride and glucose concentration respectively, and at this level of probiotic with 0- LFC the lowest count of E. Coli was observed while 12 and 24h LFC decreased bifidobacteria count (P<0.05). Villous height increased with LFC time in thoese broiler chickens fed diets contatning 0 or 0.2 g/kg probiotic. The greatest villous surface area was observed in broiler chickens fed 0.2 g/kg probiotic diet with 12h LFC (P<0.05). Conclusions: In conclusion, 12- and 24h DP decreased the performance and intestinal morphometry of broiler chickens, and double recommended probiotic supplementation could not completely ameliorate the negative effects of LFC.

Abstract Effect of different sources of probiotic and prebiotic on growth performance, carcass characteristics, intestinal microflora, and blood metabolites using 720 Ross 308 commercial male broiler chickens in a 3×3 factorial experiment with three levels of probiotic (without probiotic, probiotic type I and type 2) and three levels of prebiotic (without prebiotic, prebiotic type 1 and type II), in a completely randomized design with nine experimental groups (four replications and 20 birds were studied in each replication. Birds that were fed with diets containing type 2 probiotics had a lower conversion factor (P<0.05). Diets containing prebiotic type 1 as well as diets containing probiotic type II and diets containing probiotic type II and two prebiotics under test reduced serum cholesterol and LDL concentrations (P < 0.05). The effect of the experimental treatments on carcass fat was not significant, but the birds fed diets containing prebiotic type 1 had less abdominal fat (P<0.05). At 21 days old, the population of ٍ E. coli in the ileum and ceca of birds that received probiotics, prebiotics, and their combinations decreased (P < 0.05). At 38 days of age, feeding the birds with probiotics and prebiotics and a combination of them reduced the population of E. coli in the ceca and increased lactobacillus in the ileum (P < 0.05). The results of this experiment showed that probiotics or prebiotics assayed in this study have positive effects on the increase of beneficial intestinal bacteria (Acid lactic bacteria), blood biochemical traits, and FCR in broiler chickens.

Abstract In order to investigate the effects of using live, autolyzed yeast and their combination on performance, and intestinal histology in Japanese quail, 360 of one-day-old chicks were used. Birds were randomly divided into 4 experimental groups in a completely randomized design with 6 replicates. The experimental groups included the control group: fed with basal diet without additives, the second group: fed with basal diet containing 0.4% live yeast, the third group: fed with basal diet containing 0.4% autolyzed yeast and the fourth group: fed with basal diet containing 0.2% live yeast and 0.2% autolyzed yeast. The results showed that the addition of autolyzed yeast caused the greatest increase in body weight gain compared to the control and their mixture in the whole period of experiment (P<0.05). The weight of thigh and pancreas as well as the length of duodenum increased significantly in birds fed with autolyzed yeast compared to live yeast and their mixture (P<0.05). The highest height of duodenal villi was observed in birds fed with autolyzed yeast and live yeast compared to the control treatment and their mixture. Birds fed with autolyzed yeast showed a significant decrease in E. coli bacteria and an increase in Lactobacillus bacteria (P<0.05). The results showed that the use of autolyzed yeast as well as live yeast can be useful in feeding Japanese quails due to improving performance, increasing the height of duodenal villi, reducing the microbial population of E. coli and increasing the cecal population of Lactobacillus.

Abstract Introduction: Exposure of poultry birds to extreme temperature stressor modulates the immune responsiveness and haemato-biochemical parameters of birds. Cold temperature can increase ascites susceptibility by increasing both metabolic oxygen requirements and pulmonary hypertension. Biochar is an ash substance that is produced from the burning of biological material via pyrolysis. This study was carried out to investigate the effects of wet Litter Biochar on performance of cold-stressed broiler chickens. Material and Methods: In this experiment, the effect of wet litter biochar (WLB), probiotic and zeolite on performance, blood metabolites and small intestine morphology of broiler chickens reared under cold stress were investigated. In a completely randomized design 350 Ross-308 broiler chickens (one-day-old, mixed sexes) were allocated to seven treatments, five replicates and 10 birds in each replicate. Experimental treatments included: 1) positive control (basal diet in recommended temperature), 2) negative control (basal diet+ cold stress), 3) negative control+ %0.5 WLB, 4) negative control+ %0.75 WLB, 5) negative control+ 1% WLB, 6) negative control+ 0.02% probiotic Ecobacto-P, and 7) negative control+ 1% zeolite. In cold stress groups, house temperature decreased to 17° C from 7 d until end of the experiment (42 d). Results and Discussion: As compared to group reared in recommended house, cold stress significantly decreased broiler chickens feed intake, body weight gain (BWG), carcass and abdominal fat percentages, serum triglyceride concentration, activity of aspartate transaminase and alanine aminotransferase enzymes as well as villous width of jejunum and ileum while increased total and ascitic mortality, ileal and jejunal villous height and crypt depth to villous length ratio (P<0.05). Inclusion of 0.5 and 1% WLB and probiotic increased broiler chickens BWG, ileal and jejunal villous length and surface area, but decreased feed conversion ratio as compared to negative control group (P<0.05). Conclusion: Generally, although addition of wet litter biochar and probiotic led to improvement in performance and small intestine morphometry of cold-stressed broiler chickens, but they did not completely catch-up negative effects of cold stress on broiler chickens.

Abstract The effect of Betaplus probiotic levels in the diet on growth performance and histomorphometry of Japanese quail jejunum was investigated by using 288 broiler chicks with six treatments of four replications and 12 birds per each in a completely randomized design from one to 42 days of age. Treatments included: control group (without additives); three diets containing levels of 0.5, 1 and 1.5 g/kg of Betaplus probiotic; diet with deficient in protein, and diet with deficient in protein and contained 1 g/kg of Betaplus. Feed intake, body weight and increase body weight were measured weekly and conversion factor was calculated. At 42 days of age, two birds were randomly selected from each replicate and the traits related to carcass dissection were assessed. For histomorphometrical evaluation of the intestine, the jejunum samples were collected. The utility of betaplus probiotic at level 1 g/kg improved food intake, weight gain, conversion factor and some histomorphometrical parameters of jejunum (p <0.05), In birds were feed with level of 1.5 g/kg Betaplus, the villi thickness and crypt diameter and number of the goblet cells were decreased (p <0.05). According to the results, the use of Betaplus probiotic at level 1 g/kg in the diet improves the growth performance and histological parameters of the jejunum in Japanese quail.

Abstract The current study aimed to investigate the effects of adding probiotic and encapsulated thyme essential oil (TEO) on growth performance and immune responses of broiler chicks by multi attribute decision making (MADM). In the current study, 420 broiler chicks were allocated into 7 experimental groups with 6 replication and 10 broiler chicks per replication for 42 days. The experimental treatments were included 1) diet lack of TEO and probiotic (control), 2) diet containing 100 mg probiotic, 3) diet containing 100 mg TEO,  4) diet containing 200 mg probiotic, 5) diet containing 200 mg TEO, 6) diet containing 100 mg probiotic+100 mg TEO, and 7) diet containing  200 mg TEO+ 200 mg probiotic. Growth performance and humoral immune responses were investigated. Index weights for weight gain, feed conversion ratio, production index were 0.2, 0.15 and 0.25, respectively and index weight of 0.1 was considered for other parameters. Coefficients for control, probiotic 100, TEO 100, probiotic 200, TEO 200, probiotic 100 + TEO 100 and probiotic 200 + TEO 200 were 0.0476, 0.126, 0.198, 0.315, 0.427, 0.727 and 0.956, respectively. Thus, adding 100 mg probiotic and 100 mg TEO into diet increased immune response and growth performance. Based on obtained results, it is suggested that dietary inclusion of 100 mg TEO + 100 mg probiotic in diet of broiler chicks has a potential to improve immune response and growth performance.

Abstract In this research the effect of using domestic (Multibehcil) and imported (Bioplus B2) probiotic supplements and Avilamycin antibiotics were investigated on performance, parameters of blood lipid and small intestine morphology by a sample of 360 male Ross-308 broilers aging 11 to 42 days-old in a completely randomized design with 6 treatments, 4 replications and 15 chickens per each replicate. Experimental treatments included 1) without additive (control), 2) diets containing 0.1% of commercial bioplus B2 probiotic, 3) diets containing 0.01% of avilamycin antibiotic and treatments 4) to 6) diets containing 0.05%, 1% and 0.15% of Multibehcil, respectively. The results showed that body weight and feed conversion ratio was improved by using bioplus B2 probiotic and antibiotic (P < 0.05). Body weight and feed conversion ratio in birds receiving 0.1% and 0.15% of Multibehcil were not significantly different from birds receiving bioplus probiotic. Feed intake was not affected by the experimental treatments. Humoral immune response and intestinal morphological parameters in birds receiving 0.15% of Multibehcil was not significantly different from the control group and it was statistically equal to the groups receiving bioplus probiotics and antibiotics. The LDL level of blood showed a significant decrease in Bioplus B2, antibiotic and 0.15% of Multibehcil treatments (P < 0.05). In general, the results indicated that using of Multibehcil at the level of 0.15 percent can be a suitable alternative for both Bioplus B2 and Avilamycin during grower and finisher period in broilers.

Abstract The effect of use of acetic acid, propionic acid, butyric acid, and probiotic on productive performance of laying hens and some quality parameters of produced eggs was evaluated using an experiment with 320 Bowens laying hens, in a 4×2 factorial experiment with four fatty acid levels (no additive, 0.1 % diet, propionic acid, 0.2 % diet, butyric acid and 0.3 % diet, acetic acid) and two levels of probiotic (0 and 0.01% diet) in a completely randomized design with 8 treatments, 5 replications and 8 birds per replication. The results of production performance showed that the egg weight, feed conversion ratio, production percentage and egg mass parameters, were not affected by the experimental groups. The main effects showed that organic acid supplementation significantly increased feed intake (P<0.05). It was shown that the percentage, diameter and color index of the yolk were not affected but the height of the yolk was improved by supplements (P<0.05). The results of shell quality also showed that specific gravity, shell percentage and shell thickness were not affected by the experimental groups, but diets containing organic acids and probiotic significantly improved shell resistance compared with non-additive group (P<0.05). It could be concluded that organic acid and probiotic supplements with a positive effect on feed consumption, egg weight, egg yolk height and shell resistance, improved production performance and quality of produced eggs.

Abstract The effect of essential oils blend, probiotic and flavomycin on performance, gastrointestinal tract (GIT) characteristics, cecal microbial population and blood parameters was studied with 288 day-old chickens, Ross 308 broilers from 1 to 42 days of age in a completely randomized design by 4 treatments, 4 replicates and 18 chickens in each replication. The experimental treatments were: 1) basal diet as control group (without additive), 2) basal diet + 150 mg/kg essential oils blend, 3) basal diet + 200 mg/kg Gallipro® probiotic, and 4) basal diet + 150 mg/kg flavomycin. The results showed that feed intake was lower in the control group than other treatments (P<0.05). In the whole trial period, the weight gain of chickens fed with the diet containing flavomycin was higher than other birds and had a better feed conversion ratio than control birds or fed with the diet contains probiotic (P<0.05). The effect of treatments was not significant on relative weight of internal organs, pH of the GIT digesta and Lactobacillus and Escherichia coli population in the ceca. The relative weight of the breast was greater in chickens fed with flavomycin than control group or birds that received essential oils blend (P<0.05). There was no difference between treatments in terms of plasma cholesterol, glucose and triglyceride concentrations, but HDL concentration was lower in the plasma of birds receiving flavomycin compared to other treatments (P<0.05). Based on the results of this study, adding essential oils blend to the diet improved performance and can be used as a growth promoter instead of flavomycin in broilers diet.

Abstract The aim of this study was to examine the effects of Artemisia annua L. essential oil (AAEO) and probiotic (Lactobacillus acidophilus) on egg and carcass quality of laying Japanese quails. A total of 180 46-d-old female Japanese quail were randomly allocated to 4 dietary treatments in a completely randomized design with five replicates and nine birds per each. The experimental diets were: 1) basal diet as control group (without additive), 2) basal diet plus oxytetracycline (200 mg/kg), 3) basal diet plus AAEO (250 mg/kg) and 4) basal diet plus probiotic (4 CFU Lactobacillus acidophilus per kg diet). Results showed that the use of probiotic caused to an increase in the cumulative egg weight and daily egg mass, when compared with control and AAEO treatments (P<0.05). In comparison to control group, supplementing the basal diet with AAEO resulted in decreases on MDA level of egg yolk (P<0.05) and liver weight (P=0.06). In addition, the F3 and F2 follicles weights were increased when the basal diet supplemented with each of the feed additives (P <0.05). It can be concluded that, Lactobacillus acidophilus can be used as an alternative to antibiotics for increasing the egg production, and AAEO can be used to produce healthy products in feeding laying Japanese quails.

Abstract The purpose of this experiment was to evaluate the effect of probiotic and peribiotic supplements on performance of Holstein dairy cows. For this purpose, 40 Holstein dairy cows with daily milk production of 33 ± 0/8 kg and initial weight 700 ± 40 kg were divided into four groups in a completely randomized design. The experimental treatments consisted: 1- control group (basic diet) 2- probiotic group (base diet + 4 gr probiotic per head per day) 3- prebiotic group (base diet + 14 gr perbiotypes per Ross per day) 4- Synbiotic group (base diet + 4 gr probiotic + 14 gr perbiotic per head per day). The results of this experiment showed that there was a significant difference between the average duration of chewing, rumination and eating among different diets (P <0.05). The most duration of chewing, rumination and eating belonged to the group that consumed probiotics and had a significant difference with other groups (P <0.05). Probiotics consumption increased the amount of daily milk production, milk production with 3.5% fat and milk production with 4% fat, and a significant difference (P <0.05) with the control group (basal diet without additive). Feed efficiency increased in supplementary rations and resulted in a better performance of probiotic diets. Health indicators, consistency and fluidity of stool in supplementary diets have also improved.

Abstract Using 350 Ross broiler chickens, the effect of licorice extract (LE), probiotic, antifungal and boiler litter biochar on performance of broiler chickens fed aflatoxin B1 contaminated diet in a completely randomized design with 7 treatment (negative control (basal diet without aflatoxin and additives), positive control (basal diet + 1 mg aflatoxin B1 and without additives) and 5 other treatments were positive control with LE (3 and 6 g/kg), Protexin probiotic (0.5 gr), Agrabond (0.5 gr/kg) and biochar toxin binder (10 g/kg)) and 5 replicates (10 birds in each replicate) considered. The treatments were. The result showed that aflatoxin B1 lowered body weight gain and breast relative weight and increased FCR and abdominal fat of broilers (P < 0.05). Broilers fed negative control, 3 g/kg LE and biochar containing diets during the growing period and birds fed negative control and 3 g/kg LE during the entire period had higher BW and lower FCR as compared to other groups (P < 0.05). Negative control diet decreased breast relative weight and tight meat crude protein percent, while all of the additives led to improving these traits since the highest relative weight of breast and tight meat crude protein percent were observed in probiotic and biochar groups respectively (P < 0.05). The highest serum total protein was seen in broilers fed negative control and 3 g/kg LE diets while the lowest serum uric acid was observed in broilers fed negative control, 6 g/kg LE, Agrabond and biochar diets (P < 0.05). In conclusion, licorice extract and broiler litter biochar additives decreased adverse effects of aflatoxin B1 on broiler chickens performance.

Abstract This study was conducted to determine the effect of commercial bacterial probiotic on milk yield and composition, blood metabolites andenzyme activities in lactating ewes based on a completely randomized design (two treatments and eight replicateseach). The ewes were kept in the individual pens and fed a diet based on alfalfa hay (60%) and concentrates (40%) with or without probiotic. Milk production of the individual ewes was measured and sampled weekly for 12 weeks and blood samples were obtained at four, eight and 12 weeks of lactation before and six hours after feeding. Data were analyzed by repeated measurements procedure. No significant differences were observed due to the addition of probiotic in milk production and chemical composition, but it was changed pattern of milk production during lactation period. The probiotic increased (P<0.01) alanine amino transferase and alkaline phosphatase activities both before and after feeding at four, eight and eight, 12 weeks, respectively. Aspartate transaminase activity was also higher before feeding at eight week (P<0.05) and before and after feeding at 12 week (P<0.01) in experimental treatment. Overall, the probiotic has no significant effect on the production and chemical composition of milk of ewes, but could change the pattern of milk production and some parameters of blood plasma in Mehraban ewes during lactation period.

Abstract In this study, the effect of fat source and type of growth promoting additives in laying hens diets‌ on productive performance and egg quality traits was investigated. In a (2×3) factorial experiment,108 ninety-six week-old Hy-Line W-36 laying hens treated with 2 fat sources (vegtable fat - yellow grease and fat powder) and 3 types of growth promoting additives (none-additive,probiotic and antibiotic) for 12 weeks.The birds were allocated randomly in six treatments with six replicates (3 birds per replicat). Results showed that None of the performance variables (egg production rate, egg mass, average egg weight, feed intake and feed conversion ratio) were affected by the supplemental fat sources (P> 0.05). The addition of probiotic in feed resulted in significant reductions in feed intake, egg production and egg mass as well as in yolk percent (P< 0.05). Interactions between fat source and growth promoting additive type as well as the main effect of fat type on Egg shell thickness were significant. Thus, it could be suggested that the use of the fat sources and growth promoting additives in layer diets as a potential solution to prevent the egg shell quality problems during the late stages of production; however supplemental probiotic reduced feed intake, egg production and egg mass.

Abstract Effects of feeding a commercial probiotic (primalac) on performance and carcass characteristics of Morkhoz goat kids were studied using 16 male kids (13.2 ± 1.6 kg body weight, 3 months old) based on a completely randomized design (2 treatments and 8 replicates). For this purpose kids were fed for 119 days. The amount of feed consumption was recorded daily and body weight gain and feed conversion ratio were recorded and calculated monthly. Blood samples were collected from jugular vein three times during the experimental period, in equal intervals. At the end of the experimental period animals from each treatment were slaughtered to determine the carcass characteristics. Feeding probiotic did not affect performance parameters including the final live body weight, average feed intake, average daily gain, and feed conversion ratio. With the exception of creatinine concentration, which was lower (P<0.05) in probiotic consuming animals, plasma concentration of other metabolites did not affect by the probiotic consumption. Carcass characteristics measured in this study including weights of live body, carcasss, gastrointestinal tract, liver, heart and internal adipose tissues, weights of neck, rib, loin and long leg cuts and rib eye area did not affect by the treatments and only back fat thickness and shoulder weight were affected (P<0.05). In conclusion, it seems that the probiotic used in this experiment had no effect on performance and carcass chararcteristics of healthy, growing Morkhoz goat kids.

Abstract Effect of probiotic, prebiotic and synbiotic in protein-deficient diets on performance and intestinal histomorphometry were investigated in a 2 × 4 factorial experiment. The treatments were arranged in two levels of protein (recommended and 10 percent less than requirements), and four types of additives (without additives, probiotics Gallipro, prebiotic Technomos and a mixture of them) in a completely randomized design with eight treatments and four replicates and 25 birds per each. Birds fed on low protein diet had more feed intake and feed conversion ratio (P<0.05). Feed conversion ratio of birds fed on additives (probiotics, Probiotic and synbiotic) diets was lower than of others (P<0.05). The Relative weight of cecea in birds fed on diets containing low protein was higher than of others (P<0.05). An increase in crypt depth of duodenum and a reduction in villi length in jejenum and villi length: crypt depth ratio in deudenum and jejenum were observed by feeding protein dificeint diets (P<0.05). Villi length in the duodenum of birds fed on additive-less diet were lower than of birds fed diets containing prebiotic  or mixture of probiotic and prebiotic  (P<0.05). Villi length: crypt depth ratio in jejenum of birds fed on diets containing recommended protein and mixture of probiotic and prebiotic were higher than of others (P<0.05). Villi length in ileum were increased by adding the mixture of probiotic and prebiotic to the diet (P<0.05). Villi thickness in the ileum of birds that were received synbiotic was lower than of birds that fed on diets containing prebiotics (P<0.05). It could be concluded that using of probiotic, prebiotic and their mixtre in protein deficient diets, improve the feed conversion ratio in Japanese quail by improving intestinal histomorphometric parameters.

Abstract The present study was carried out to evaluate the effects of vegetable fat sources and additives on performance and morphological parameters of the small intestine of Arain broiler chickens. Birds were randomly used in a 2×3 factorial arrangement of dietary treatments included two fat sources (canola or pumpkin seed) and three additives (without additive, 0.1 g/kg probiotic and 0.15 g/kg virginamycin) with four pen replicates and 20 birds per each. The growth performance and productive traits, with using of neither additives nor fat sources or fat sources × additives were unaffected. However, probiotic was significantly decreased crypt depth and increased villi height to crypt depth ratio in jejunum and ileum (P<0.01). Likewise, the highest of villi height and villi height to crypt depth ratio in jejunum and ileum especially was obtained with combination of pumpkin seed oil and probiotic (P<0.05). Crypt depth, villi thickness and surface area was higher in duodenum of broilers were fed with pumpkin seed oil (P<0.05).Thus, probiotic bactocell can be used in diets contain linoleic-oleic (pumpkin seed oil) and linolenic (canola oil) fat groups without negative effect on performance and productive traits.

Abstract Effect of probiotic (Clostat) levels on the performance and immune response of heat stressed broilers, was evaluated in a completely randomized design on 144 day-old male Ross broiler chicks with four treatments and four replicates (nine birds each). Experimental diets were consisted in four levels of probiotic (0, 0.05, 0.1 and 0.2). Birds were raised under normal condition till 25 days of age and then were exposed to heat stress (34±2°C for eight hours/day) till the end of trial. The results showed that the effect of probiotic on feed intake was not significant, while birds receiving 0.05 and 0.1 percent probiotic had more body weight gain (P<0.05) compared with control birds. Feed conversion ratio (FCR) was better with 0.1 percent probiotic. Increasing probiotic levels, increased relative weight of carcass, breast meat and liver (P<0.05). Blood cholesterol concentration was decreased by probiotic levels (P<0.01). Heterophil and heterophil to lymphocyte ratio was decreased and glutathione peroxidase increased by probiotic addition. It is concluded that dietary supplementation of 0.1 percent probiotic may improve broiler growth performance and immunity under heat stress condition.

Abstract To evaluate effects of adding two probiotics (Thepax and Yeasturer) and two prebiotics (Fermacto and A-Max), and one synbiotic (Biomin) to iso-caloric and iso-nitrogenous diet (ME = 2720 kcal/kg and CP =145 g/kg) on performance of laying hens and egg quality traits, 216 Lohmann LSL-Lite 76-wk old laying hens were divided in 36 cages (n = 6). Productive performance of hens was recorded for six weeks and egg quality characteristics were measured on the last week of trial. Feed additives did not have significant effect on EP, FCR, FI and EM in the present study. Including diets with feed additives in the present experiment significantly increased EW. Egg shell weight and shell thickness were increased in the hens fed additive-included diets compared to hens fed the control diet. In conclusion, feed additives used in this investigation did have beneficial effects on egg quality characteristics in terms of egg shell weight and shell thickness, with no beneficial effects on hens' productive performance.

Abstract The effects of probiotics and antibiotics and fat type in diet on broiler performance were studied by using 900 one-day old Ross 308 chicks in a three × three factorial arrangement with three types of fat (nonfat, three percent fatty acid and three percent soy oil) and three growth promoters (without GP, flavomycin and protexin) in completely randomized design with four replicates per each treatment. Fat and its type had significant effects on weight gain and the body weight gain of birds fed diets containing soy oil were better (P< 0.05). Dietary flavomycin supplementation improved weight gain and FCR (P< 0.05). The fat type × growth promoter’s interaction influenced broiler performance, significantly (P< 0.05). Birds fed on diets containing soy oil and flavomycin showed the highest feed intake and weight gain, whereas, the lowest feed intake and weight gain was belonged to birds fed diets containing fat and protexin (P< 0.05). From the results obtained, it can be indicated that addition of protexin to diets containing fat has negative effect on broiler growth performance.

Abstract In this study, the effect of different levels of fat with antibiotics and probiotics on blood biochemical traits and performance of broiler chicks was investigated. In a factorial experiment, 288 Day-old Ross broiler chicks treated with two level of fat (3 and 6 percent) and three additives (Flavomycin, Protexin and none-additive). The birds were allocated randomly in six treatments with four replicates and 12 birds per replicat. Results showed that the chicks fed on diets containing 3 percent of fat + Flavomycin had higher feed intake and body weight gain compared to birds fed with fat + Protexin (P< 0.05). The concentration of cholesterol, HDL and LDL in serum of birds of 6% fat was more than of those fed diets with 3% fat. Birds fed diets containing protexin had lowest cholesterol, HDL and LDL (P< 0.05). It was concluded that supplementing the rations containing fat with probiotics decrease feed intake and body weight gain in broilers chicks and their performance decrease by increasing fat in diets.