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The aim of this study was to examine the suitability of different growth functions (linear, sinusoidal, Gompertz, Schumacher and Richards) to fit cumulative milk production data from buffalo cows. Cumulative milk production at each day in milk was calculated from two published datasets reporting (i) fortnightly test-day milk yield records of the first lactation of Murrah buffalo that had calved during 1977–2012 and (ii) the first lactation records of Jaffarabadi buffalo collected from history-cum-pedigree registers for each quinquennium between 1991 and 2010. Each function was fitted to the lactation curves using nonlinear regression procedures. The Richards and sinusoidal equations provided the smallest root mean square error values, Akaike's and Bayesian information criteria and, therefore, the best fit for the cumulative lactation curves for milk yield. The Richards equation appeared to provide the most accurate estimate of the cumulative milk production at peak milk yield. Sinusoidal and flexible classical growth functions are appropriate to describe cumulative milk production curves and estimate lactation traits in buffalo. [ABSTRACT FROM AUTHOR]

Context: Broiler chickens are exposed to various stressors, which can affect production performance. The use of dietary probiotics is one of the feasible methods to maintain performance, intestinal health, humeral immunity, and ameliorating physiological stress in the broiler. Aims: In all, 288 1-day-old male broiler chicks were used to evaluate the effect of probiotic supplementation on performance, morphology, and gene expression associated with immune responses in the starter phase of broiler chickens exposed to stress. Methods: In total, 288 1-day-old male broiler chicks (Ross 308) were assigned to evaluate the effects of Bacillus subtilis spore (BSS; Gallipro®200) supplementation at three levels (0, 0.8 × 105 colony-forming units (CFU) and 1.6 × 105 CFU/g feed) with corticosterone (CORT; 4 mg/kg BW at 7–9 days of age) or without CORT (oil) subcutaneous injection. The experiment was conducted in a completely randomised 2 × 3 factorial design. Key results: CORT injection and probiotic supplementation led to an increase and decrease respectively, in food conversion ratio compared with the control group (P < 0.05). CORT injections reduced the expression of TLR4, HSP70 and IgA in all parts of the intestine. However, the TLR4 gene expression increased in jejunum by CORT injections. BSS supplementation induced the expression of TLR4 in all sections of the intestine, both in stress and non-stress conditions. In stress-exposed chickens, IgA expression in the jejunum was affected by BSS supplementation. Interaction effects between CORT injections and BSS supplementation on the gene expression were significant in different parts of the intestine. Conclusions: Chicks exposed to stress conditions induced by CORT injection showed that the ileum was more susceptible than were the other parts, especially for TLR4 and HSP70 gene expression. BSS-supplemented birds showed more capability to face the stress condition, probably due to intestinal health and immunity-modulated effect of BSS. Implication: Formulating a ration with a probiotic can be more effective in stress conditions, through modulating immune-responsive genes in the intestine. The effects of various environmental stresses on the behavioral, physiological, and performance responses of birds have been studied for years. It has been shown that probiotics, also known direct-feed microbes, substantially influence nutrient digestibility, gut microflora and immunity, and inhibit pathogens and, ultimately, improve growth performance in broilers. Our findings suggested that formulating a ration with probiotic can be more effective in stress condition, with immune response genes modulating the effect in the intestine of broiler chicken. [ABSTRACT FROM AUTHOR]

BACKGROUND: The application of phytogenic additives in the form of essential oils have attracted considerable attention in poultry industry. OBJECTIVES: An experiment was conducted to evaluate effects of the blends of essential oils (EO) isolated from some medicinal plants including savory, thyme, fennel and rosemary on performance, blood metabolites, intestinal microflora, and meat quality of broilers. METHODS: Two hundred 1-day-old broilers were randomly allocated to 5 treatments with 4 replicates of 10 chicks. The dietary treatments included 1) NC (negative control; without EO), 2) PC (positive control; 300 mg commercial EO of oregano/kg diet), 3) SR (300 mg EOs of savory and rosemary/kg diet), 4) SRT (300 mg EOs of savory, rosemary and thyme/kg diet), 5) SRTF (300 mg EOs of savory, rosemary, thyme and fennel/kg diet). RESULTS: Neither PC nor combinations of EOs affected growth performance of broilers. Serum cholesterol reduced (P<0.05) by feeding the blend of EOs compared with NC. The lowest ileal Lactobacillus counts were observed in chicks fed diets supplemented with EO of oregano or SR (P<0.05). Dietary supplementation of oregano EO decreased (P<0.05) lipid peroxidation of thigh meat after 30 and 60 days of frozen storage compared with NC group. CONCLUSIONS: Broilers fed diets supplemented with EOs of oregano or SR had the lowest ileal Lactobacillus spp. counts probably due to their large amount of carvacrol contents which suppress growth and proliferation of Gram-positive bacteria. Contrary to blended EOs, oregano EO did not reduce serum cholesterol concentration, suggesting hypocholesterolemic effect of other compounds except carvacrol in EOs. The highest stability to meat oxidation was achieved in oregano EOs-fed broilers. This antioxidative effect was lower in treatments with less carvacrol contents. [ABSTRACT FROM AUTHOR]