ABSTRACT
The objective of this study was to assess the importance of strain and sex and their interaction effect on broiler chickens performance and susceptibility to ascites. Chicks from three strains [Ross 308, Cobb 500 and Arian, labeled as A, B and C respectively] were obtained from the same age breeder and sexed when one-day-old. Each crosses' sex was assigned to four pens of 60 broilers each. Body weight gain [BWG] feed intake, feed conversion ratio [FCR] and ascites mortality were determined. At the age of 28 and 49 d haematocrit values, arterial pressure index [API = right ventricular/total ventricular weight ratio] the values of plasma thyroid hormone concentration [thyroxin, T4 and triiodothyronine, T3] and metabolic lung weight [lung weight/body weight [0.75]] were determined. Strain B had the highest BWG but an equal incidence of ascites as strain A, which had low BWG and ascites mortality. Ascites mortality was not correlated with BWG and FCR. A significant strain interaction by sex on feed conversion [P<0.01] and final weight [P<0.05] was found. The sex effect was significant only in strain C on feed conversion and final weight. Strains B and C had lower thyroid hormones and reduced metabolic lung weights compared with strain A. The sex effect was not significant on the parameters associated with ascites syndrome and its incidence
ABSTRACT
Thyme extract had shown to have antimicrobial and autoxidative activities. It is claimed that it causes reduction in serum cholesterol and improves immune system. An experiment was conducted to investigate the effect of dietary Thyme extract on serum cholesterol, yolk cholesterol and immune system under heat stress in laying hens. for six weeks with 108 hens from Lohman strain of 45 weeks old. The experiment had a 2× 2 × 3 factorial arrangement. Treatments include cyclic hot and neutral temperature, two fat sources of saturated and unsaturated and tree experimental treatments of control group [without additive], vitamin E and thyme extract. To determine the factors which affect on antibody production, the Sheep Red Blood Cell [SRBC] was injected on the day 30 and 37 following the start of experiment. Statistical analysis has shown a significant increase differences between the level of serum cholesterol and yolk cholesterol significantly under heat stress [p<0.05]. Saturated fat significantly increased yolk cholesterol [p<0.05]. However, thyme treatment decreased serum and yolk cholesterol [p<0.05]. In addition, temperature had significant effect on first and second antibody titer [p<0.05]. Furthermore, in second SRBC injection, thyme had the highest significant effect on antibody increment [p<0.05]. Phenolic compounds within thymol reduced serum cholesterol and improved immune response especially in high environment temperature
ABSTRACT
This study was carried out to examine aflatoxin B[1] [AFB[1]] removal ability of four strains of lactic acid bacteria [LAB]
Three indigenous (Lactobacillus rhamnosus TMU094, Lactobacillus fermentum TMU121 and Pedioccus pentosaceus TMU457] and a non-indigenous [Labacillus rhamnosus PTCC1637] isolates were studied. The strains were incubated with [AFB[1]] at different time. The toxin residual in the supernatant was determined. Reduction of the toxin quantity was observed by all species. Binding of aflatoxin by the studied LAB varied from 19.41 to 75.06%. Aflatoxin-binding activity showed time dependent trend taking into consideration of different incubation periods. Lactobacillus rhamnosus TMU094 bound 25.64 to 75.06%, L. fermentum bound 38.63 to 72.15%, P. pentosaceus bound 24.86 to 63.21% and L. rhamnosus PTCC1637 bound 19.41 to 35% of AFB[1] during the studied course of incubation times. These results showed that indigenous strains of LAB are able to bind AFB1 effectively?
ABSTRACT
Poultry requirements for vitamins and minerals are met from two sources feed ingredients and premixes. In practical poultry nutrition, the role of feed ingredients is over looked. This experiment was conducted to evaluate the effects of the time of vitamin and mineral premixes withdrawal on growth and economic performance of broilers. Four hundred and fifty, one day-old male broiler chickens [Ross 308] were used in a completely randomized design with 6 treatments of 5 replicates. Chicks were fed on a common starter diet formulated based on corn and soybean meal, with common vitamin and mineral premix [VMP] levels [0.25% each] for the first week. Then, the treatments 1 to 6 were constructed, on the basis of withdrawal time of VMP, in a way that treatment numbers were represented the number of weeks fed on VMP supplemented diet. The results showed that VMP withdrawal from 7,14 and 21 days of age decreased daily weight gain and feed intake significantly [p<0.01], and impaired feed efficiency [p<0.01]. While VMP withdrawal from day 28 and day 35, did not influence weight gain, feed intake and feed efficiency. Relative weights of abdominal fat, bursa of fabricius and spleen, and carcass yields were not influenced by VMP withdrawal. The overall results of the present study, considering economical aspects showed that the removal of vitamin and trace mineral supplements from 7 days prior to slaughter can reduce production costs without negative consequences on growth performance of broiler chickens
Subject(s)
Male , Animals , Minerals , Chickens/growth & development , Economics , GrowthABSTRACT
This study was conducted to investigate the effects of diets containing different levels of hull-less barley on caecal microflora of broiler chicks. Two hundred and forty one-day old male broiler chicks [Arbor Acres strain] were used in a completely randomized design with 4 tratments, and 3 replicates were allocated to each treatment. Different levels of hull-less barley in diets had not significant effects on total bacterial count, E.coli, Clostridia and Lactobacillus population in caeca at starter period [21 days old], but at 49 days of age, caecal Lactobacilus population increased significantly by increasing the levels of hull-less barley in diets[p<0.05]. Based on the results of the present study, it can be stated that inclusion of hull-less barley in diets, changes the caecal microflora of broiler chicks. These components reduced pathogenic bacteria [Clostridia] and increased the usefull bacteria [Lactobacillus]
Subject(s)
Animals , Cecum , Chickens , Clostridium , Lactobacillus , Escherichia coliABSTRACT
In this study, 480 on-day-old Arbor broiler chicks were used in a 2 [asterisk] 3 factorial arrangement with 2 levels of hull-less barley [0.30%] and 3 levels of enzyme [0.300 and 600 g/ton], to investigate the effect of diets containing high soluble non-starch polysaccharides [NSPs] concentrations on morphological characteristics of small intestine and performance of broilers. Increasing in concentration of soluble NSPs significantly decreased feed intake and body weight gains of broilers, [p<0.05] height and width of villi and tongue shaped villi percentage but increased other types of villi and crypt depth in small intestine [p<0.01], Enzyme supplementation of diets had no significant effects on studied traits, results show increase in the concentration of soluble NSPs of diet causes negative effects on morphological characteristics of small intestine in broiler chicks. Therefore, it could reduce absorption surface in digestive tract, and consequently decrease broiler performance