Effect of Different Levels of Dietary Selenium on growth performance and nutrient utilization of broiler birds

Experiment was conducted on 120 broiler chicks for six weeks and their weight gain was taken for consecutive six weeks to observe the effect of different levels of dietary selenium over growth and nutrient utilization of birds. There were three diets prepared with 0.125, 0.15 and 0.175 mg Se/Kg feed for group T1, T2 and T3 respectively. The FCR and st performance index at 1 week for T1 were 1.34±0.02 and 21.21±0.36 that for T2 was 1.51±0.01 and 16.56±0.40 and for th T3 were 1.29±0.02 and 23.88±0.50, the experiment continues for 6 weeks the FCR and performance index at 6 week in T1, T2 and T3 was 3.42±0.19 and 7.37±0.78, 3.56±0.05 and 6.51±0.25, 3.56±0.15 and 6.85±0.58. The percent retention of nutrients was highest in T3 group as compare to T1 and T2 which was supplemented @ 17.50 mg Se/kg of feed. Therefore it was concluded that supplementation of selenium @ 17.50 mg/kg diet of poultry enhances the growth rate as well as nutrient retention in the broiler birds.


Introduction
one hundred twenty broiler chicks (1 d old) were randomly assigned to 12 cages containing 10 chicks Selenium is an essential trace element occurring each, corresponding to each of 3 dietary treatments. in organic and inorganic forms.The organic form is The ingredients and composition of the starter and found predominantly in grains, fish, meat, poultry, and basal diets are shown in Tables 1. Treatment 1 (T1) dairy products (Klein, 2004).Selenium has been contains 25 mg (200 kg feed) (@ 0.125 mg/kg of diet) shown to have an analogous function as an essential selenium while, T2 diet contains 30 mg (@ 0.15 mg/kg component of the Se-dependent glutathione of diet) selenium and diet T3 contains 35 mg (@ 0.175 peroxidase (Combs, 1981).This enzyme protects cells mg/kg of diet) selenium.The chicks were maintained against damage caused by free radicals (Flohe, 1997).on a 24-h constant lighting schedule and allowed The supplementation of feeds with Se is achieved with access to feed and water ad.lib.until slaughter at 42 mainly inorganic sources of Se such as Na SeO day of age.The body weight and feed consumption for (sodium selenite).High levels of dietary Se result in the individual pens were recorded at 1, 7, 14, 21, 32, higher liver, kidney, plasma, and muscle Se and 42 d.Before slaughter of birds three days concentrations in poultry (Echevarria et al., 1988).metabolic trial was conducted to observed the effect of Selenium is an essential micronutrient required dietary selenium over the nutrient utilization of the for normal growth and maintenance in poultry.The birds.Percent composition of concentrate mixture recommended selenium concentration in broiler diet given to the chicks was presented in table 01. is 0.15 mg/kg (NRC, 1994).Swain et al. (2000) Metabolic trial: At the end of the feeding trial, four reported the maximum daily weight gain and highest (4) birds per replicate were randomly selected and feed conversion in chickens that received 0.50 mg transferred to metabolic cages for faecal collection to Se/kg and 300 IU/kg vitamin E.
determine the apparent nutrient digestibility.The birds The present study was conducted to determine were allowed to adjust to the cages for three days.The the effect of various dietary levels of supplemental Se digestibility trial lasted 4 days.The total collection on the growth performance and nutrient utilization of procedure was employed for the faecal collection.broiler chickens.
Polythene sheet spread underneath the cages was used for faecal collection.Feathers and other dirts were

Materials and Methods
hand picked and discarded from the faeces before Birds and Diets: The experiment was conducted on weighing.
The collections for each day were dried in a hot utilization of the birds in all the three supplemented 0 groups.The concentrate mixture was analysed for dry air oven at 60 C. The samples of each replicate were matter, crude protein, crude fibre and ether extract by allowed to cool in glass desiccators to prevent further the method of A.O. A.C (1980).The chemical absorption of moisture from the atmosphere.The 4 composition of concentrate mixture fed to the birds at days samples were pooled, ground and then analyzed the time of metabolic trial was presented in Table -3.for crude protein, crude fibre, ether extract and total The faecal sample collected during the ash according to the method of AOAC (2003).
metabolic trial was chemically analyzed for dry

Results and Discussion
matter, crude protein, crude fibre and ether extract as per the method by A.O. A.C (1980).The chemical Performance of the broiler was determined by composition of faecal samples was presented in the observing their body weight at weekly intervals.The Table -3.overall average body weight of the birds from 0-6 The percent retention of nutrients was calculated weeks were presented in the  by calculating the total intake and total outgo of the Performance of Broiler Chicks: The different level nutrients.Such as in group I the DM intake during the of selenium in the diet of the broiler bird from 0 week period of metabolic trial was 167.83 g while outgo was to 6 week of age doesn't have any significant effect on 43.12 g therefore the percent retention of DM was the weight gain.The average weight gain of the birds 74.30.Same as that of protein the percent retention from the age of 0-6 weeks ranges from 25.36 to 28.02 was 68.71 %, Crude fiber retention in group I was g.Average feed intake per day per bird during 6 week 77.41% and that of ether extract was 84.84 %.Nutrient period ranges from 66.50 g in group II to 68.02 g in retention in group I was lowest among all the three group III.Feed conversion ratio (FCR) was similar in supplemented groups.Percent retention of nutrients in group I and group III i.e. 2.61 and slightly higher in group I was presented in

Table - 1. Percent composition of concentrate mixture along with the composition of selenium in individual diets.
Table-4. group II i.e. 2.73.Performance Index in all the threeIn group II the percent retention of DM was groups for the period of 6 weeks ranges from 10.81 in found to be 85.43 while, protein comes to be 71.44 % group II to 13.40 in group III.The results were in agreement with the results ofGuo et al. (2001)and that of crude fiber and ether extract was 77.71% and Effect of Different Levels of Dietary Selenium on growth performance and nutrient utilization of broiler birds

Table - 2. Overall performance of the broiler (0-6 week)
Effect of Different Levels of Dietary Selenium on growth performance and nutrient utilization of broiler birdsEffect of time and high dietary selenium on tissue group III among all the three experimental groups.The selenium uptake.Poult.Sci., 67:1295Sci., 67: -1301..DM retention was 89.12% that of crude protein, crude 4. Flohe, L.(1997).Selenium in peroxide metabolism.Med.fiber and ether extract was 80.15%, 80.17% and tissue peroxidation of broiler chicks and the stability of thigh meat against oxidative deterioration.Anim.FeedSci.