Iranian Journal of Animal Science Research
Year:2009 | Volume:1 | Issue:2|Papers Count:12

This study was aimed to determine the effects of different dietary levels of methionine and protein on the growth performance and carcass characteristics of broiler chickens. A total of 240 broiler chicks were distributed into a completely randomized design with a 2´3 factorial arrangement. Experimental factors were: two levels of protein (20% or 24% for starter and 18% or 22% for grower), and three levels of methionine (standard, 115% standard and 130% standard). The experiment consisted of 6 treatments with four replicates and 10 birds in each replicate. All diets were calculated to be isocaloric for starter (7 to 21 d) and grower (22 to 42 d) periods. Birds had free access to feed and water throughout the experimental period. Mean body weight (BW) and feed intake were determined at the end of each period. On days 43 two birds were randomly selected from each pen and individually weighed and slaughtered. Then, carcass weight and weight of parts (yield of breast and abdominal fat pat) were determined. The results indicated that excessive levels of methionine and dietary protein improved weight gain and feed conversion ratio (FCR) at starter, grower and total periods. Feed intake was not affect by the increase in dietary methionine and protein levels. The increase in dietary methionine and protein levels was affective in increasing breast meat yield and decreasing abdominal fat pad. There were no interactions between methionine and protein for BW, FCR or carcass characteristics.

An experiment was conducted to evaluate the effects of microbial phytase on apparent digestibility of crude protein (CP), amino acids (AA), and apparent retention of calcium (Ca), total phosphorus (tP), iron (Fe) and zinc (Zn) in female broiler chickens diet. The experiment was designed as a completely randomized design. Each treatment consisted of 4 replicates of 10 broilers in battery cages, for a total of 240 chicks. The birds were fed similar diets containing six levels of microbial phytase (0, 250, 500, 750, 1000 and 1250 FTU/kg of diet) during 1-28 days of age. Excreta were quantitatively collected during 21-24 days of age. The excreta stored at -20ºC, freeze-dried and analyzed for AA, Cp, Ca, tP, Fe and Zn. During the experiment, body weight gain, feed intake, and feed conversion ratio were measured weekly interval basis. 250 and 500 FTU phytase significantly improved apparent digestibility of CP and AA (except than alanine, valine and threonine) (P<0.05). Phytase had a significant effect on apparent retention of Fe and Zn (P<0.05), but did not affect Ca and tP apparent retention (P>0.05). Phytase had no significant effect on body weight gain, feed intake and feed efficiency (P>0.05).

This study investigated genetic variation within indigenous chicken of Khorasan using four microsatellite markers (MCW5, MCW16, MCW18 and MCW34). 90 blood samples were collected from this population and phenol-chloroform extraction method was used to isolate the DNA. The highest and the lowest allele number and effective alleles are shown in MCW5 (6 and 5.293) and MCW34 (4 and 3.138), respectively. The expected heterozygosis varied from 0.8157 (MCW5) to 0.6854 (MCW34). The amount of genetic variation within this population was found 0.74 this could be due to low inbreeding in this population. The Hardy-Weinberg equilibrium (HWE) test showed that all loci deviated from HWE (p<0.005). To short, then results of this study suggested that microsatellite DNA markers are useful tools for studying the genetic relationships among native chicken breeds. This is the first genetical study on indigenous chicken of Khorasan.

One experiment was conducted in order to evaluate four levels of macaroni waste including: 0, 10, 20 and 30 percent age in growing turkey feed in a completely randomized design (CRD) with 120 local turkey including 3 replicates in 12 pens. During the experiment (3-8 weeks), turkeys received feed and water of free access. Weight gain, feed consumption and feed efficiency were measured weekly. Different levels of macaroni waste had no significant effects on feed consumption, but level of 20 percentage of macaroni waste had lowest feed consumption (2072.91gram). Weight gain and feed efficiency were significantly (P<0.05) affected by various levels of macaroni waste, the level of 20 percentage had the highest weight gain (926.47 gram) and lowest feed efficiency (2.237). The results of this experiment indicated that level of 20 percentage of macaroni waste in dietary local turkey at 3-8 weekly had the best performance and the lowest feed cost per kilogram weight gain comparison with other levels.

This experiment was carried out to study the effect of manganese in four levels (30, 60, 90 and 120 mg/kg) and zinc in four levels (50, 100, 150 and 200 mg/kg) on shells with translucent areas, Haugh unit, mortality, percentage of ash in eggshell and composition of eggshell in laying hens, in a completely randomized design and in a 4´4 (16 treatment) factorial arrangement, three hundred and twenty (320) white leghorn laying hens, strain Hy-Line W36 and 28 weeks old were divided in to 64 replicate, five hens per replicate. The experimental period lasted 90 day until hens were 40 weeks of age. The result indicated that manganese and zinc in combination and alone had not a significant effect on mortality and Haugh unit but had a significant effect on percentage of ash in eggshell and shells with translucent areas (P<0.01).

A total of 260709 monthly test day milk records of 30903 first lactation Holstein cows was used to determine the best function to describe the lactation curve. The records were obtained from first lactation Holstein of 216 herds from 1988 to 2006 in Khorasan province. The functions used in current study were Wood’s incomplete gamma function, Ali and Schaeffer function, and Legendre function of fifth order. Six criteria including error sum of squares, mean error sum of squares, coefficient of determination, adjusted coefficient of determination, correlation coefficient and variance inflation factor were used to compare the performance of the functions. The results indicated that Ali and Schaeffer function was more preferable than other functions when the variance inflation factor was ignored. However the Legendre function was found to be more appropriate than other functions when the variance inflation factor was considered.

An experiment was conducted to evaluate the effect of early feed restriction on performance and serum thyroxin concentration of broiler chicks. The experiment was designed in a 2´2 factorial with 5 replicates of floor pens with 12 male or female chicks in each. 240 male and/or female day-old chicks of a commercial strain (Hybrow) were wing banded, weighed and randomly allocated to two treatment groups of each sex. Two treatments involved, one control group (no restriction) and one restricted group, which were fed a mixture of 50:50 rice hulls and commercial starter diet with supplementation of trace minerals & vitamin premixes from 4 to 11 days of age. All groups were fed the same starter, grower & finisher diets from 11 to 56 days of age. Live body weight (LBW) of restricted birds was compensated on day 42 of age and was greater than restricted group at 49 and 56 days of age. Mean daily feed intake and feed conversion ratio up to 42, 49 and 56 days of age wasn't affected significantly by treatments. Feed cost per kg of LBW in Restricted birds markedly improved in compare to control group. Furthermore, feed cost per kg of LBW for male chicks was lower than of female chicks. Carcass fat content of restricted birds was significantly lower than of control birds. Also, carcass fat content of male chicks was significantly lower than of female chicks. Abdominal fat of restricted birds at 49 and 56 days of age was significantly lower than of control birds. Mean LBW up to 42, 49 and 56 days of age, weight gain and feed intake for male chicks was more than female chicks. Serum thyroxin concentration on day 11 in restricted group was significantly lower than control group but its concentration during accelerated growth period (28-49 days of age) in restricted group was non-significantly more than control group. Results of this experiment showed that, broiler chickens after early feed restriction compensated the retarded growth and showed less abdominal and carcass fat content.

Three multiparoys lactating sannen dairy goats in midlactation with mean milk production and DIM pf 1.5±0.22 kg and 167±4 days were used to determine effects of the abomasal infusion wheat starch, wheat starch or cottonseed oil with casein on performance of sannen dairy goats. Goats were fed ad libitum with basal diet include, 40% hay alfalfa and 60% concentrate. Treatments were abomasal infusion of 1 wheat starch (100g/d), 2 wheat starch and casein (100 g/d and 50 g/d respectively) and 3 cottonseed oil and casein (45 g/d and 50 g/d). Infusion of starch of cottonseed oil with casein increased milk yield, percentage and yield lactose, NPN, and whey protein were not affected by treatments. Infusion of wheat starch with casein decreased milk fat concentration. Intake of DM, OM, CP, NDF, ADF and EE in total tract were not different among treatments. No effect on ruminal pH, rumen ammonia concentration and glucose, blood urea nitrogen and triglyceride of plasma were absorved. In general, it is concluded using of casein with starch and oil in postruminal had positive effect on milk yield and milk protein.

This experiment was conducted to increase the resistance of tiger barb (Capoeta tetrazona) against environmental stress by feeding brackish water Gammarus sp. Powder as supplementary diet in three levels (25%, 50% and 75%) and three replicates pe group compared to control group for 60 days. fishes was fed with 4 diet treatment containea of: 100% artificial diet (control group), 25% brakish water gammarus and 75% artificial diet, 50% brakish water gammarus and 50% artificial diet and 75% brackish water gammarus and 25% artifical diet. At the end of experiment, the group that was fed with 25% brackish water gammarus powder and 75% artificial food in exposed to pH=3.8, temperature=15c and deficiency of oxygen hat a significant higher for survival than other groups. At the results obtained, it can be suggested that using of 25% brackish water Gammarus powder with artificial diet SFT00 for rainbow trout is suitable for production of highly quality ornamental tiger fish.

One-hundred-sixty-eight 28-wk-old Hy-line layers (W-36) were used to evaluate the effect of different levels of linseed (LS) and safflower seed (SS) on antibody titter, blood and yolk cholesterol, yolk fatty acid content and the ratio of omega-6/omega-3. Hens were randomly assaigned in a compeletly randomised design each 3 replicates of 8 hens. They were fed diets contained 0, 4, 7 and 10% LS or SS for 12 wks. As a result, antibody titter, mean yolk and blood cholesterol content were not affected by dietary treatments. Dietary linseed or safflower seed did not significantly affect saturated fatty acids (meristat, palemitat and stearat), w-7 (palemitoleat) and w-9 (oleat), arachidonat and long chain omega-3 polyunsaturated fatty acids (eicosapentanoeic and docosahexaenoic acid) in egg yolk. The linoleic acid in yolk was reduced when LS was included in diet, whereas they were significantly increased when fed diets contained SS. The yolk linolenic acid was increased linearly as the level of LS increased from 0 to 10%, but not affected by SS treatment. Although yolk w-6/ w -3 ratio content increased to 21.87 when 10% SS diet was fed, but it reduced from 1.86 in those fed 10% LS diet. It seems that inclusion of SS and LS in laying hen dits can increase the polyunsaturated fatty acid; however, the inclusion LS in laying hen dits increase and decrease the yolk sum of w -3 fatty acids and the yolk ratio of w -6/ w -3 respectively.

The aim of this study was to evaluate the effect of substitution of soybean meal with canola meal and measure its effects on rumen anaerobic fungal population in lactation Iranian of Holstein cows. From d 5 to 56 postpartum, cows were fed diets that were is oenergetic containing soybean meal (SBM; n = 3) or canola meal (CM; n = 3). Cows were housed in tie stalls and fed TMR two times a day. Competitive PCR technique was used to evaluate quantitative difference of anaerobic fungal population within the rumen under the dietary groups. Universal primers were used to amplify a specific region of the rRNA locus from anaerobic rumen fungi. Standard control DNA was constructed for use in the competitive PCR and was shown to amplify under the same reaction condition and with the same amplification efficiency as the target DNA. The relative intensities of PCR products were used to compare variety of fungal population under fed treatments. The signal intensity was quantified by Image J 1.29x and expressed in arbitrary units. The data was analyzed using the GLM procedure of SAS for a completely randomized design. The rumen fungal population was not impacted by diet but numerically was decreased in the CM compare with the SBM diet (34.79 and 35.12±1.87 arbitrary units, respectively). The results of this study demonstrated that substituting soybean meal with canola meal in the early lactation cows had no apparent effect on the fungal population.

An experiment with 240 one-day-old Lohman male broilers was conducted to investigate the effects of different levels of palm kernel meal supplemented diet with/without enzyme on performance and lactic acid bacteria population of ceca. Birds were distributed in 20 experimental units and data were analyzed in a complete randomized design with 2x2 arrangement plus a control diet. The levels of palm kernel meal were 5% and 10% of diet and levels of enzyme were %0.035 and %0.07. Four replicate of 12 birds were assigned to each dietary treatment. Diets were fed to broilers from 0 to 42 days of age. Feed intake, body weight gain, feed conversion ratio and lactic acid bacteria population in ceca were measured in this trial. Feed intake during 0 to 21 and 22 to 42 days of age and feed conversion ratio during 0 to 21 days of age were affected by level of palm kernel meal. But palm kernel meal had no significant effect on other measured parameters. Different levels of enzyme had no significant effect on feed intake, body weight gain, feed conversion ratio during 0-42 days of age and lactic acid bacteria population of ceca measured at 42-day-old. The results of this experiment showed that there was no significant difference between performance parameters treatments contains palm kernel meal plus enzyme and control treatment during 0 to 42 days. However the mean of lactic acid bacteria population of ceca at 42-day-old birds indicated a non significant increased in population of diets contains palm kernel meal.