ABSTRACT:The aim of the present study was to evaluate the effect of commercial monostrain and multistrain probiotics in diets on growth performance, intestinal morphology and mucin gene (MUC2) expression in broiler chicks. Three hundred seventy-eight 1-d-old male Arian broiler chicks were allocated in 3 experimental groups for 6 wk. The birds were fed on a corn-soybean based diet and depending on the addition were labeled as follows: control-unsupplemented (C), birds supplemented with Bacillus subtilis (BS) and lactic acid bacteria (LAB) based probiotics. Each treatment had 6 replicates of 21 broilers each. Treatment effects on body weight, feed intake, feed conversion ratio and biomarkers such as intestinal goblet cell density, villus length, villus width, and mucin gene expression were determined. Total feed intake did not differ significantly between control birds and those fed a diet with probiotics (p>0.05). However, significant differences in growth performance were found. Final body weight at 42 d of age was higher in birds fed a diet with probiotics compared to those fed a diet without probiotic (p<0.05). Inclusion of Bacillus subtilis based probiotic in the diets also significantly affected feed conversion rate (FCR) compared with control birds (p<0.05). No differences in growth performance were observed in birds fed different types of probiotic supplemented diets. Inclusion of lactic acid bacteria based probiotic in the diets significantly increased goblet cell number and villus length (p<0.05). Furthermore, diets with Bacillus subtilis based probiotics significantly increased gene expression (p<0.05), with higher intestinal MUC2 mRNA in birds fed diet with probiotics compared to those fed the control diet. In BS and LAB probiotic fed chicks, higher growth performance may be related to higher expression of the MUC2 gene in goblet cells and/or morphological change of small intestinal tract. The higher synthesis of the mucin gene after probiotic administration may positively affect bacterial interactions in the intestinal digestive tract, intestinal mucosal cell proliferation and consequently efficient nutrient absorption.

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The effects of stocking density and environmental conditions on performance, economic profit, carcase characteristics, immunity, and blood plasma parameters of Cobb 500 strain of broiler chickens were evaluated. The 4 climate regions (mild and humid, semi-arid, alpine, hot and dry) and 4 densities (10, 15, 17 and 20 chicks/m 2 ) were carried out as a completely randomised design with 4 Â 4 factorial arrangement of treatments. The corn and soybean based diets were formulated according to the nutrition requirements guide of the Cobb 500 for starter and grower periods. The amount and the composition of the diet were the same for all experimental groups. Growth performance and feed intake were measured weekly. After the injection of sheep red blood cell at 15 and 35 days, blood samples were taken at 24 and 42 days, respectively, to study the immunity of broiler chickens. At the end of the experiment, 3 birds were slaughtered from each experimental unit for measuring the weights of carcase, abdominal fat, gastrointestinal organs (the total weight of gastrointestinal tract and caeca, and liver) and blood parameters. The interaction effects of stocking density and climate region on feed conversion ratio (in starter period), survival rate, cost, profit, cholesterol, triglyceride, high density lipoproteins (HDL), HDL/low density lipoproteins (LDL) ratio, and liver enzymes aspartate aminotranferases (AST), also known as serum glutamic oxaloacetic transaminase (SGOT), and alanine aminotranferase (ALT) were significant (p < .05). Climate and density each had a significant effect on production index (p < .05). The highest production index was obtained in alpine climate. Moreover, the density of 10 chicks/m 2 showed the highest production index. The results showed that rearing Cobb strain chickens in hot and dry climate and at the density of 17 chicks/m 2 had the most economic benefit. Based on the results of this study to achieve the highest profit in different climates, a density of 17 chicks/m 2 (0.633 ft 2 per bird) is recommended for Cobb 500 strain chickens. HIGHLIGHTSNutritional efficiency changes by environmental factors such as climate and stocking density. Obtain sufficient information to combined effect of stocking density and climate on the performance of Cobb 500 broiler chickens. The most reached profit was in the dry climate at a density of 17 chicks/m 2 compared to other climates and densities.

The effect of sourdough inoculated with three novel single strains of lactic acid bacteria (LAB) (Lactobacillus casei jQ412732, Lactobacillus plantarum jQ301799, and Lactobacillus brevis IBRC-M10790) as well as mixed strains was evaluated on the quality characteristics of Toast bread. Antifungal properties of sourdoughs due to organic acid production were measured by HPLC, and storability was evaluated by thermal and textural analysis in days 1, 3, and 6. Despite the impact of sourdough concentration on microbial preservation, no significant effect was observed in the case of enthalpy reduction. Mixed LAB strains showed the best results in reducing the enthalpy and hardness of bread as well as better microbial preservation by producing the highest amount of organic acids, justified by sensory panelists. Among single strains, L. casei gave better results in reducing hardness and staling rate of bread. Scanning Electron Microscopy micrographs of bread also showed the differences.

ABSTRACT. The edited data set for the estimation of heritability, genetic and phenotypic correlations of fertility traits contained up to 23,402 records from 10,894 cows calved between 2001 and 2015. Heritability estimates for success in first service (FS), gestation length (GL), number of inseminations (NI), insemination outcome (IO), calving interval (CI), calving birth weight (CBW) and days open (DO) were low and ranged between 0.016 (DO) and 0.123 (GL). Repeatability of fertility traits was estimated to vary from 0.021 (FS) to 0.411 (IO). The genetic correlations between DO × CI, DO × NI and CI × NI were positive and nearly perfect (0.98, 0.88 and 0.88, respectively), while those between DO × IO and CI × IO were negative (-0.98 and -1, respectively). Further, the phenotypic correlations between DO × CI, DO × NI, CI × NI, CBW × IO and SF × IO were 0.99, 0.83, 0.83, 0.99 and 1, respectively, while those between DO × IO, CI × IO, GL × IO and NI × IO were -0.99, -0.99, -0.99 and -1, respectively. Overall genetic parameters imply a good practical management in heat stress conditions will be essential for improving fertility efficiency.Keywords: heritability, repeatability, genetic correlation, phenotypic correlation, heat stress. Análise genética de traços de fertilidade em vacas leiteiras Holstein em climas quentes e temperadosRESUMO. Os dados editados para definir a estimativa de herdabilidade, correlações genéticas e fenotípicas de características de fertilidade continham até 23,402 registros a partir de 10,894 vacas paridas entre 2001 e 2015. As estimativas de herdabilidade para o sucesso no primeiro serviço (SF), duração da gestação (GL), número de inseminações (NI), resultado de inseminação (IO), intervalo entre partos (CI), peso ao nascer (CBW) e dias abertos (DO) foram baixas e variaram entre 0,016 (DO) e 0,123 (GL). A repetitividade das características de fertilidade foi estimada e variou entre 0,021 (SF) e 0,411 (IO). A correlação genética entre DO × CI, DO × NI e CI × NI foi positiva e quase perfeita (0,98, 0,88 e 0,88, respectivamente), enquanto que aquela entre DO × IO e CI × IO foi negativa (-0,98 e -1, respectivamente). A correlação fenotípica entre DO × CI, DO × NI, CI × NI, CBW × IO e SF × IO foi 0,99, 0,83, 0,83, 0,99 e 1, respectivamente, enquanto aquela entre DO × IO, CI × IO, GL × IO e NI × IO foi -0,99, -0,99, -0,99 e -1, respectivamente. Os parâmetros genéticos constatados implicam que será essencial uma gestão bem prática na condição de estresse por calor para melhoria da eficiência da fertilidade.Palavras-chave: herdabilidade, repetitividade, correlação genética, correlação fenotípica, estresse por calor.

This study was carried out to investigate a possible protein‐sparing action of l‐carnitine and ractopamine in rainbow trout, Oncorhynchus mykiss. An 8‐week feeding trial was carried out to evaluate the effects of supplementation of three levels of l‐carnitine (0, 1 and 2 g kg−1) and two levels of ractopamine (0 and 10 mg kg−1) on growth performance, fillet fatty acid compositions and blood biochemical parameters in a 3 × 2 factorial experimental design. Ractopamine and 1 g kg−1 carnitine improved the specific growth rate (1.03% and 1.05% day−1), feed conversion ratio (FCR, 1.3 and 1.29), protein efficiency ratio (PER, 1.88 and 1.85) of fish and crude protein (73.5 and 73.8) content of fish fillet. l‐carnitine and ractopamine increased the levels of albumin, total protein and globulin in the serum of fish. Apart from eicosapentaenoic acid and docosahexaenoic acid, other fatty acids of fish fillet were increased by ractopamine, while total saturated fatty acids were almost intact. However, the total n‐3 poly unsaturated fatty acids were reduced by l‐carnitine supplementation (P<0.05). The present study showed that 1 g kg−1l‐carnitine and 10 mg kg−1 ractopamine each can improve the performance of rainbow trout and their combination in diet could enhance the protein level and change the fatty acids profile in fillet muscle.

1. The objective of present study was to evaluate the effects of intra-amniotic injection of different probiotic strains (Bacillus subtilis, Enterococcus faecium and Pediococcus acidilactici) on the intestinal MUC2 gene expression, microbial population, growth performance and immune response in broiler chicken. 2. In a completely randomised design, different probiotic strains were injected into the amniotic fluid of the 480 live embryos (d 18 of incubation), with 4 treatments and 5 replicates. Ileal MUC2 gene expression, microbial profile, growth performance and immune response were determined. 3. Injection of probiotic strains, especially B. subtilis, had significant effect on expression of the MUC2 on d 21 of incubation and d 3 post-hatch, but not on d 19 of incubation. 4. Injection of the probiotic strains decreased significantly the Escherichia coli population and increased the lactic acid bacteria population during the first week post-hatch. 5. Inoculation of probiotics had no significant effect on antibody titres against Newcastle disease virus, antibody titres against sheep red blood cell and cell-mediated immune response of chickens compared to control. 6. In ovo injection of the probiotic strains had no significant effect on growth performance of broiler chickens. 7. It was concluded that injection of probiotic bacteria especially B. subtilis into the amniotic fluid has a beneficial effect on ileal MUC2 gene expression and bacteria population during the first week post-hatch, but has no effect on growth performance and immune response in broiler chickens.