most of the phosphorus (p) in feed ingredients is present as phytate, which is poorly available for absorption in the gastrointestinal tract of different poultry species due to the lack of endogenous phytase. The supplementation of phytase increases the utilization of p by hydrolyzing phytate, which consequently may reduce the excretion of p in the environment. in addition, it has been suggested that phytase may improve the feed utilization, weight gain, egg production and egg traits, nutrient digestibility, energy availability, retention of important minerals in blood and bones. Thus, the effectiveness of phytase on performance and ca and p absorption in layer chickens fed corn-soybean based diets has been well recognized. The current review briefly discusses the supplementation of phytase in the diet of poultry on performance and egg production and characteristics as well as amino acids and minerals availability.

Bacterial Kidney Disease (BKD), which is caused by a Gram-positive, intracellular bacterial pathogen (Renibacterium salmoninarum), affects salmonids including Atlantic salmon (Salmo salar). However, the transcriptome response of Atlantic salmon to BKD remained unknown before the current study. We used a 44K salmonid microarray platform to characterise the global gene expression response of Atlantic salmon to BKD. Fish (∼54 g) were injected with a dose of R. salmoninarum (H-2 strain, 2 × 10 8 CFU per fish) or sterile medium (control), and then head kidney samples were collected at 13 days post-infection/injection (dpi). Firstly, infection levels of individuals were determined through quantifying the R. salmoninarum level by RNA-based TaqMan qPCR assays. Thereafter, based on the qPCR results for infection level, fish (n = 5) that showed no (control), higher (H-BKD), or lower (L-BKD) infection level at 13 dpi were subjected to microarray analyses. We identified 6,766 and 7,729 differentially expressed probes in the H-BKD and L-BKD groups, respectively. There were 357 probes responsive to the infection level (H-BKD vs. L-BKD). Several adaptive and innate immune processes were dysregulated in R. salmoninarum-infected Atlantic salmon. Adaptive immune pathways associated with lymphocyte differentiation and activation (e.g., lymphocyte chemotaxis, T-cell activation, and immunoglobulin secretion), as well as antigen-presenting cell functions, were shown to be differentially regulated in response to BKD. The infection level-responsive transcripts were related to several mechanisms such as the JAK-STAT signalling pathway, B-cell differentiation and interleukin-1 responses. Sixty-five microarray-identified transcripts were subjected to qPCR validation, and they showed the same fold-change direction as microarray results. The qPCRvalidated transcripts studied herein play putative roles in various immune processes including pathogen recognition (e.g., tlr5), antibacterial activity (e.g., hamp and camp), regulation of immune responses (e.g., tnfrsf11b and socs1), T-/B-cell differentiation (e.g., ccl4, irf1 and ccr5), T-cell functions (e.g., rnf144a, il13ra1b and tnfrsf6b), and Eslamloo et al. Atlantic Salmon Response to BKD antigen-presenting cell functions (e.g., fcgr1). The present study revealed diverse immune mechanisms dysregulated by R. salmoninarum in Atlantic salmon, and enhanced the current understanding of Atlantic salmon response to BKD. The identified biomarker genes can be used for future studies on improving the resistance of Atlantic salmon to BKD.

Diminishing the cost of broiler chicken diet is a critical issue in the poultry industry. Numerous studies were performed to achieve this pivotal objective by diet supplementation with alternative feed additives. In the current study, low-energy broiler rations were supplemented with different commercial multienzyme formulations to minimize the cost, and increase the digestibility and absorption of the digested macronutrients. Cobb Avian 48 broiler chicks (mixed sex, 1-d-old, n = 3120) were randomly allocated into six groups, and each group was subdivided into four replicates (130 birds per replicate). The birds were randomly allocated into a control group fed basal diet (CB); control group fed low-energy diet (CL); and birds fed low-energy diets supplemented with different enzyme formulations. The enzyme formulations used were Xylam 500® (CLX group), Hemicell® (CLH group), Avizyme® (CLA group), and Megazyme® (CLM group,) following the doses recommended by the manufacturers. The growth performance of CLA and CLH group birds was significantly improved when compared with CL. In comparison with CB, Avizyme® significantly (p < 0.001) increased the intestinal PEPT1, GLUT2, ACC, and IL-2 expression; PEPT1 facilitates the absorption of micronutrients. In conclusion, exogenous multienzyme complexes may be included in the low-energy diet to enhance the performance of broiler chickens (Avizyme® ˃ Hemicell® ˃ Megazyme®), and reduce the diet cost by up-regulating the expression of intestinal nutrient transporter genes, and improving the immunity and serum biochemical parameters of broiler chickens.

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The objective of the present study was to determine the effect of feed restriction systems, herbal mixture and their interactions on growth performance, carcass traits, and microbial aspects of growing New Zealand White (NZW) rabbit kept from 5 to 13 weeks of age. A 3 Â 4 factorial arrangement was performed, including three feed restriction systems (ad-libitum, 90%, and 80% of ad-libitum) and four dietary supplementation levels of herbal mix (0, 0.30%, 0.50% and 0.70%). A total number of 120 rabbits (male and female ratio 1:1) at five weeks of age were randomly allotted into twelve experimental groups (n ¼ 10 each). Results showed a significant decrease in body weight, body weight gain and feed intake in restricted-fed rabbits compared to the control group (ad-libitum). HERBS levels significantly influenced the growth performance and carcass traits of rabbits. The herbal blend had a positive effect on reducing the population of pathogenic microorganisms and increasing the population of lactic acid bacteria. Conclusively, it could be concluded that the feed restriction system has beneficial effects in the improvement of feed conversion ratio (FCR), weight gain, and carcass traits. In addition, HERBS supplementation to the growing rabbits resulted in significant improvements in growth performance, carcass characteristics, and microbial aspects of rabbits kept from 5 to 13 weeks of age. HIGHLIGHTS:This work investigated the effect of feed restriction systems (FRS), herbal mix (HERBS), and their interactions with rabbits. Restricted feed decreased live body weight during all ages studied. Feed conversion ratio, weight gain and carcass traits were improved due to FRS. The HERBS improved the growth, carcass traits, and microbial aspects of rabbits.