Effect of Probiotics on Serum Biochemical and Blood Constituents in Chicken Challenged with Salmonella enterica Subsp Typhimurium

Purpose: To examine the effects of two commercial probiotics (Toyocerin and CloSTAT) on serum enzyme activities, and hematological and biochemical indices of broiler chickens challenged with Salmonella enterica serovars Typhimurium (ST).Methods: The chicks received one of the following treatments at 0 day of age: T1 = control group, unmedicated diet, unchallenged birds, (negative control); T2 = unmedicated diet + bacterial challenge (positive control); T3 = medicated diet with neoxyval (0.05 g/kg diet) + bacterial challenge (NEOX); T4 = toyocerin (1 g/kg diet) + bacterial challenge (Toyocerin); and T5 = CloSTAT (1 g/kg diet) + bacterial challenge (COLS). Blood samples were withdrawn from 7 selected chicks in each treatment at 7, 21, 28, 35 and 42 days of age, and analyzed for total protein, albumin and globulin concentration, and the albumin: globulin ratio computed. Glutamate-oxaloacetate transaminase (GOT) and glutatamate pyruvate transaminase (GPT) levels in serum were measured on days 7 and 42.Results: The results revealed that albumin (p < 0.001), globulin (p < 0.001) and albumin: globulin ratio (p < 0.001) were influenced by the time of blood collection. Globulin increased significantly after ST challenge while albumin decreased significantly. Glutamate oxaloacetate transaminase (GOT) after ST challenge was affected by treatment (p < 0.05). Higher levels were obtained from birds which had received NEOX or positive control, compared to negative control group.Conclusion: Salmonella challenge affects serum albumin, globulin and GOT enzyme. The results obtained suggest that the probiotic, Toyocerin, mitigates the negative effects of Salmonella challenge.Keywords: Bacillus subtilis PB6, Bacillus Cereus var. toyoi, Probiotics, Liver enzymes, Hematology, Salmonella enteric

Effects of selenium and vitamin E on performance, physiological response, and selenium balance in heat-stressed sheep

Forty-two 7-mo-old Australian Merino wethers were used in a 50-d trial to investigate the effects of Se and vitamin E on the performance and physiological responses of heat-stressed sheep. Sheep were exposed to thermoneutral conditions (maximum = 24°C and minimum = 20°C) for 28 d followed by heat (maximum = 38°C and minimum = 28°C) for 22 d. Hot conditions were imposed between 0700 and 1800 h. Sheep were randomly allocated to diets containing 0.8 mg/kg Se (Sel-Plex), 150 mg/kg vitamin E, or 0.8 mg/kg Se and 150 mg/kg vitamin E for either the duration of the study (50 d) or from d 1 of the hot period until the end of the study. A control group that received no supplemental Se and vitamin E for the duration of the study was included. Feed intake was measured daily and sheep were weighed weekly. Blood samples were collected from all sheep before feeding on d 1, 21, and 49 for measurement of biochemical and enzymatic variables. The concentration of Se was determined in offered and refused feed, feces, urine, water, plasma, liver, and kidneys. Exposure to heat reduced (P < 0.05) DMI by 11.9%, ADG by 198 g, serum concentration of urea nitrogen and Se by 17.8%, and plasma total antioxidant status by 26.4%. During hot conditions, sheep receiving Se and vitamin E supplements for 50 d had reduced (P < 0.05) BW loss and elevated G:F compared to control sheep. Serum Se concentration and the plasma total antioxidant status were greatest in sheep receiving Se and vitamin E supplements for 50 d (P < 0.05). These results indicate that dietary supplementation with Se and vitamin E reduces the adverse effects of a high heat load. Additional studies are warranted to elucidate the mechanisms responsible for these effects

Microsatellite-Based Genetic Structure and Diversity of Local Arabian Sheep Breeds

The genetic diversity of the sheep breeds in the Arab countries might be considered to be a mirror of the ecology of the region. In this study, the genetic structure and diversity of sheep breeds from Saudi Arabia (Harri, Najdi, Naemi, Arb, and Rufidi) and Awassi sheep from Jordan as an out-group were investigated using 19 microsatellites. All the breeds had high intra-population genetic diversity expressed as allelic number (7.33) and richness (2.9) and, expected heterozygosity (0.77). Structure analysis revealed three main gene pools underlying the ancestral genetic diversity of the study populations. The first pool had Harri, Najdi, and Rufidi breeds; the second had Naemi and Awassi breeds, and the third had the Arb breed which was significantly differentiated from the other breeds. Factorial correspondence analysis lent further support to the presence of the three gene pools. Although the outgroup Awassi sheep was more clearly differentiated, it still genetically close to Naemi sheep. The differentiation of the Arb breed could have been resulted from geographic and reproductive isolation. On the other hand, the genetic structure of the other two gene pools could be the result of the past and recent gene flow between individuals reared in the region known to be the center for animal husbandry and trading until the current time

Phosphorus characterization in feces from broiler chicks fed low-phytate barley diets

The inclusion of low phytate grains in poultry diets can reduce the phosphorus (P) content of poultry feces, but their influence on fecal P composition is not well established. To assess this, 100 male broiler chicks (21 days old) were fed dietary treatments based on either a wild-type barley or one of three low phytate mutant barleys with 59, 62 and 99% reductions in phytate P, compared with the normal barley diet. The birds were housed in raised-floor battery cages with mesh grate floors above fecal collection trays with five birds per pen and five pens per treatment. The birds were fed for 9 days and feces were collected twice a day during the last 2 days of the experiment. Total P concentrations were 14-24% lower in feces from birds fed low phytate barley diets compared with those fed the normal barley diet. Phosphorus digestibility increased (P < 0.05) as phytate in the barley diet decreased. Phosphate was the major P fraction in the feces (69-75% extracted P) regardless of the type of barley fed. Phytate constituted only 3-12% of the P in the feces, indicating its hydrolysis in the bird. Overall, these results suggest that feeding low-phytate barley diets can reduce P concentrations in poultry feces without causing significant changes in P composition

Effect of fat source, energy level and enzyme supplementation and their interactions on broiler performance

This study was conducted to evaluate the effects of replacing soybean oil (SBO), typical in broiler diets, with a less expensive commercial fat blend, Kofat (KOF). A 2 x 2 x 2 factorial experimental design was used to study the interactions of the two fat sources, SBO and KOF, at two levels of metabolizable energy (ME) (low and normal) with the inclusion or not of an enzyme, Tomoko (TOM), in broiler diets. The broilers were fed ad libitum in cages from 1 to 30 days of age. Two hundred one-day-old male (Ross 308) chicks were distributed among 40 cages with five replicates per treatment, and received a starter diet from 1 to 16 days and a finisher diet for days 17 to 30. Cumulative feed intake was not influenced by fat source, energy level or TOM supplementation for the starter, finisher or total periods. For the total period (1 to 30 days), energy x enzyme interaction was significant for bodyweight gain (BWG) and feed conversion ratio (FCR). The TOM supplementation had a positive effect on the low energy diet and a negative effect on the normal energy diet with respect to BWG and FCR. The TOM enzyme was able to restore the nutritional value in the low energy diet. Fat source had no influence on performance of broilers during the experiment period. It was concluded that KOF as a source of fat and the enzyme, TOM at a rate of 0.05%, can be included in a broiler diet where the ME level has been reduced by 414 kJ/kg during the starter and finisher periods.Keywords: Broilers, energy level, Kofat, performance, soybean oil, Tomok