The aim of the study was to determine the effect of yeast probiotic on body weight, and the activities of anti-oxidant enzymes: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), and malondialdehyde (MDA) concentration of broiler chickens. The experiment was carried out on hybrid Hubbard broiler chickens (n = 200). Two-hundred day-old chicks were randomly selected and distributed into four groups of 50 day-old chicks each: Control, C, and treatment groups comprising T₁, T₂ and T₃ administered with 0.25 mL, 0.5 mL and 1.0 mL yeast probiotic, respectively. Chicks were fed a commercial starter diet for the first 28 days of age, followed by pelleted finisher diet from 29 to 42 days. Chickens in T₁ had a significantly (p < 0.01) higher body weight at 4th week of age when compared with the control. SOD activity in all treatment groups was not significantly (p > 0.05) different when compared with the control. GPx activity was significantly (p < 0.01) higher in T₁, when compared with the control. GPx activity in T₂ was higher (p < 0.01) when compared with the control. There was no significant (p > 0.05) difference in MDA level in all the treatment groups. In conclusion, administering yeast probiotic supplement increased body weight and enhanced serum anti-oxidant enzyme activities of broiler chickens.

Clinical and experimental evidence suggests that hyperglycaemia is responsible for the oxidative stress in diabetes mellitus. The study was designed to investigate the comparative effects of probiotic and vitamin C (Vit-C) treatments on hyperglycaemia, oxidative stress and dyslipidaemia in alloxan-induced diabetic rats. Type 1 diabetes (T1DM) was induced in male Wistar rats by a single intraperitoneal (i.p.) injection of alloxan (150 mg/kg). Six groups of the animals received the following treatment regimens for four weeks: (1) Normal saline, per os; (2) alloxan (150 mg/kg, i.p.); (3) alloxan (150 mg/kg) + insulin (4 U/kg, subcutaneously); (4) alloxan (150 mg/kg) + probiotic (4.125 × 10⁶ CFU/100 mL per os); (5) alloxan (150 mg/kg) + Vit-C (100 mg/kg, i.m.); (6) alloxan (150 mg/kg) + probiotic (4.125 × 10⁶ CFU/100 mL per os) + Vit-C (100 mg/kg, intramuscularly). Probiotic + Vit-C decreased (p < 0.05) blood glucose concentration in diabetic treated group, when compared with the untreated diabetic group. Probiotic + Vit-C reduced malondialdehyde concentration, in the serum, brain and kidneys, respectively, but increased the activity of antioxidant enzymes. Probiotic and Vit-C may be more effective than Vit-C alone, in ameliorating hyperglycaemia, oxidative stress and dyslipidaemia in alloxan-induced diabetic rats.

In poultry, the benefits of probiotic supplementation on broiler performance and health have been reported. The present study examined the effect of supplemental yeast probiotic preparations on body weight, thyroid hormone metabolism and serum lipid profile in broilers. The experiment was carried out on hybrid Marshall broiler chickens (n=200). Two hundred 1-day-old chicks were randomly selected and distributed into 4 groups of 50 1-day-old chicks each (control, C; E10.5%, E21.5% and E32.0%, experimental groups). The birds were housed in an environmentally controlled poultry house with the floor covered with wood shavings. Chicks were fed commercial broiler starter diet for the first 28 days of age, followed by pelleted finisher diet from 29–42 days. Feed and water were provided ad libitum. Chickens fed 2.0% probiotic had a significantly (P<0.05) higher body weight when compared with the control group. The blood glucose concentration was significantly (P<0.05) different in the E31.5% probiotic supplemented group when compared with the control. There was highly significant (P<0.05) difference in T4 level in the E32.0% probiotic group when compared with the control. However, there was a significant difference in cholesterol concentrations observed in the experimental group supplemented with E10.5% probiotic. The concentration of triglycerides was not affected by the probiotic supplementation. Significant differences (P<0.01) were observed in HDL concentrations in all experimental groups supplemented with the probiotic when compared with the control group. In conclusion, supplementing broiler feeds with a yeast probiotic increased body weight, enhanced thyroid hormone metabolism, and decreased cholesterol and lipoproteins in broiler chickens.

The aim of the experiment was to evaluate effects of zinc gluconate (ZnGlu) and probiotic administration on the daily rhythm of cloacal temperature (t_cloacal) in broiler chickens of different age groups during the hot‐dry season. One‐day‐old broiler chicks (n = 60) were divided into groups I–IV of 15 chicks per group, and treated for 35 days: Group I (control) was given deionized water; Group II, ZnGlu (50 mg/kg); Group III, probiotic (4.125 × 10⁶ cfu/100 mL), and Group IV, ZnGlu (50 mg/kg) + probiotic (4.125 × 10⁶ cfu/100 mL). Air dry‐bulb temperature (t_db), relative humidity (RH), and temperature‐humidity index (THI) inside the pen, and t_cloacal of each broiler chick were obtained bihourly over a 24‐h period; on days 21, 28, and 35 of the study. Values of t_db (32.10 ± 0.49°C), RH (49.94 ± 1.91%), and THI (38.85 ± 0.42) obtained were outside the thermoneutral zone for broiler chickens, and suggested that the birds were subjected to heat stress. Application of the periodic model showed disruption of daily rhythm of t_cloacal in broilers on day 21, which was synchronized by probiotic administration. The administration of probiotics or ZnGlu + probiotics to a greater extent decreased the mesor and amplitude, delayed the acrophases of t_cloacal in broilers, especially at day 35, as compared to the controls. Overall, the t_cloacal values in broiler chickens administered with probiotic alone (41.25 ± 0.05°C) and ZnGlu + probiotic (41.52 ± 0.05°C) were lower (P < 0.001) than that of the controls (41.94 ± 0.06°C). In conclusion, probiotic alone synchronized t_cloacal of the birds at day 21, and, in addition, decreased t_cloacal response most, followed by its coadministration with ZnGlu, the antioxidants may be beneficial in modulating daily rhythmicity of t_cloacal and alleviating adverse effects of heat stress on broiler chickens during the hot‐dry season.

Several studies carried out on humans and other mammals show that the temporal organisation of haematological parameters in the blood exhibit daily rhythms; however, such studies have been rare in poultry reared under a natural photoperiod. The present study investigated the occurrence of daily rhythms in blood parameters of broiler chickens kept under tropical climatic conditions. Ten 6-7-week-old broiler chickens served as subjects of the study. They were kept in standard individual cages under natural light-dark cycle and given access to feed and water ad libitum. Two milliliters of blood was collected from each bird via intravenous cannulae inserted into the wing vein. The blood samples were collected every 4 h over a 24-h period, starting from 09:00 h on the first day and completed at 09:00 h on the second day. The blood samples were analysed for erythrocyte, total and differential leucocyte counts. A trigonometric statistical model according to the single cosinor procedure was used to describe the periodic parameters and their acrophases, and ANOVA was used to determine significant differences. The results demonstrated the existence of daily rhythms in packed cell volume, haemoglobin, white blood cell, red blood cell, heterophil, lymphocyte, eosinophil and monocyte counts, while total protein displayed no rhythm. The characteristics of the haematological parameters showed that the acrophases were restricted to the light phase of the light/dark cycle, precisely at 09:00 h, except for eosinophil and heterophil counts, which had acrophases at 21:00 h. The amplitudes of the blood parameters varied, with packed cell volume having the greatest amplitude of 4.2 ± 0.5, closely followed by lymphocyte (3.4 ± 0.5) and heterophil (2.3 ± 0.2) counts. In conclusion, the results of the study demonstrated the existence of daily rhythms with diurnal acrophases in blood parameters of broiler chickens kept under natural photoperiods and tropical conditions.