فصلنامه تحقیقات تولیدات دامی
سال هشتم شماره 3 (پاییز 1398)

This research was conducted to evaluate the effects of different levels of nucleotide supplementation on growth performance and immune responses of broiler chickens. An experiment was conducted as a completely randomized design using 300 day-old male chicks, were divided into five treatments with five replicates and 12 chicks in each replicate. The treatments consisted of the basal diet without additives (control), the basal ration + 500 g/ton of probiotic CloSTAT, basal diet + 400, 500 and 600 g/ton enriched nucleotide supplement, respectively. Daily feed intake, daily body weight gain and feed conversion ratio were measured at the end of each period. Humoral and cellular immunities were evaluated by intramuscular injection of sheep red blood cell (SRBC) and intradermal injection of phytohemagglutinin-P (PHA-P) in wing, respectively. The results indicated that all levels of the nucleotide reduced the daily feed intake (89.7, 83.3 and 79.4 vs. 98.2 g, respectively) and improved feed conversion ratio (1.67, 1.62 and 1.62 vs. 1.93, respectively; P<0.05).  On day 28, probiotic CloSTAT and 400 and 500 g/ton of nucleotide had higher levels of total anti-SRBC (5.20, 6.60 and 6.90 vs. 3.20) and IgM (2.60, 3.20 and 2.20 vs. 0.90; P<0.05). On day 35, the treatments of 400 and 500 g/ton nucleotide have higher total anti-SRBC (6.60 and 6.10 vs. 3.80 and 4.50), IgG (3.50 and 3.30 vs. 2.10 and 2.50) and IgM (3.10 and 2.80 vs. 1.70 and 2.00) than the control group and probiotic CloSTAT (P<0.05).  Cell immunity in response to PHA-P injection was not affected by treatment groups (P>0.05). It is concluded that consumption of 400 and 500 g/ton enriched nucleotide supplement in the diet has beneficial effects on performance and immune responses of broiler chicks.

The aim of this study was toinvestigate the effect of pomegranate peel extract (PPE) on the growthperformance, carcass characteristics, blood indices, intestinal morphology andmeat stability of broiler chickens. A total of 120 one-day-old Ross 308chicks were used in this study in a completely randomized design with threetreatments each replicated four times. The experimental treatments included were:0, 300 and 600 mg PPE/kg. Allstarter rations had four percentages of canola oil and grower and finisherdiets had six percentages of canola oil. The results showed that the PPE had nosignificant effect on performance of broiler chicks, including feed intake,body weight and feed conversion ratio. Pomegranate peel extracts (600 mgPPE/kg) increased the relative weight of bursa of fabricus (0.22 vs.0.11%) and decreased abdominal fat (0.92 vs. 1.93%) as compared tocontrol. The 600 PPE diet had lower concentration of serum cholesterol (147.95 vs.155.78 mg/dL), and LDL (44.45 vs. 53.36 mg/dL) than control diet (P<0.05). Compared to control group, thelevel of 600 PPE reduced the activity of lactatedehydrogenase (1111 vs. 2182 μL) and aspartate aminotransferase (210 vs.239 u/L). The stability of the meat during storage (0.85 vs. 0.99 ng/g) increasedin birds fed diets contained PPE as compared with control group. The birdsreceived PPE had higher jejunal villus height (1245 vs. 1027 μm) and thecrypt depth to the villus height (6.74 vs. 5.05) compared to the control.It is concluded that PPE supplementation at the level of 600 mg/kg of diet improvedmeat stability and morphology of jejunum and reduced the blood cholesterol ofbroiler chickens.

The aim of this study was to investigate the effect of dietary inclusion of butyric acid, multi-enzyme or their combination on growth performance, intestinal morphology and bone ash percentage of tarsometatarsus and toe in broiler chickens. A total of 450 male broiler chicks (Ross 308) were randomly allocated in a completely randomized design with five treatments and six replicates and 15 birds in each replicate for 42 days. The experimental treatments consisted of T1) a positive control, T2) a negative control (low-nutrient; the concentration of nutrients was 5% lower than those of high-nutrient diets), T3) a negative control+ multiple-enzyme complex (Natuzyme Plus), T4) a negative control+ butyric acid (Baby C4) and T5) a negative control+ multiple-enzyme+ butyric acid. Average daily weight gain increased in positive control (T1) compared to other treatments (P<0.001) and T3, T4 and T5 treatments had higher average daily weight gain compared to T2 treatment. Feed conversion ratio in T1 treatment was lower than T2 treatment, but other treatments had no significant difference. The T4 treatment caused to increase relative ileum weight compared with other treatments (P<0.05). The T3 and T4 treatments caused to increase villus height compared to T2 treatment but differences were not significant. Also, T3 and T5 treatments caused to increase production index compared to T2 treatment (P<0.001). The higher nutritional profit in T1 and T3 treatments was observed compared to T2 treatment (P<0.05). There was no significant difference in percentage of bone ash between the treatments (P>0.05). In conclusion, the use of only multi-enzyme was advisable for improving growth performance, however, the use of combination of butyric acid and multi-enzyme supplements did not provide greater improvement in performance.

In this study effect of fish meal and soybean meal supplementation was investigated on quantity and quality of colostrum and blood parameters in pregnant ewes. A total of 40 multiparous ewes (average body weight of 68 ± 6.3 kg) during last month of gestation were fed with one of the four experimental diets including basal diet (CON), basal diet + 5% fish meal (T1), basal diet + 5% soybean meal (T2) and basal diet + 2.5% soybean meal + 2.5% fish meal (T3). The quantity of colostrum production was determined at six h post-partum using oxytocin injection method. The quantity of colostrum in T1, T2 and T3 was higher (P<0.05) than that in CON and the highest amount of colostrum production was obtained from group receiving basal diet + 2.5% soybean meal+2.5% fish meal (T3). Ewes in 5% fish meal group (T1) had higher (P<0.05) colostrum IgG concentration than ewes in other groups. The experimental treatments reduced the glucose concentration of the blood in pre-partum ewes (P<0.05). The addition of undegradable protein sources decreased the BHBA concentration and increased IgG concentration in the post- partum ewes (P<0.05). The lowest concentrations of glucose and NEFA in post-partum ewes were in the 5% soybean group (P <0.05). In conclusion, undegradable protein supplementation during late gestation increased serum IgG concentrations and improved colostrum quantity and quality in pregnant ewes.

This study was conducted to evaluate nutritive value of whole cucumber plant (WCP) and then, assessing its different dietary levels effects on in vitro gas production and rumen fermentation parameters using cow rumen liqour. For this purpose, firstly chemical composition and rumen fermentation kinetics of WCP were compared with wheat straw (WS) and alfalfa hay. After that, the effects of substituting levels of 0, 5, 10, 15 and 20% WCP for forage part of the diet were investigated on in vitro digestion and fermentation parameters. Results indicated that WCP had lower dry matter (DM), organic matter (OM) and lignin contents than alfalfa and WS (P<0.05). However, its crude protein (CP) was considerably higher than WS and also was comparable with alflalfa CP content. Neutral detergent fibre and acid detergent fibre contents of WCP were lower than WS (P<0.05), but they were similar to alfalfa. Incubation of WCP showed higher total gas production (GP), potential of GP (b), DM and OM digestibility and microbial mass production than WS, while they were lower than alfalfa (P<0.05). In conclusion, results of present study showed that WCP has favourable chemical composition and nutritive value compared to WS, and its CP content also is comparable with alfalfa. Moreover, its incorporation in ruminant nutrition up to 20% of diet is recommended.

The aim of this research was to study the effects of supplementation of alfalfa silage with a combination of essential oils and fresh apple pulp and on the dry matter, organic matter and crude protein degradabilities by nylon bags. The treatments included: 1) alfalfa silage (control treatment), 2) alfalfa silage processed with essential oil, 3) alfalfa silage (75%) + apple pulp (25%), 4) alfalfa silage (75%) + apple pulp (25%) + essential oil, 5) alfalfa silage (50%) + apple pulp (50%), 6) alfalfa silage (50%) + apple pulp (50%) + essential oil, 7) alfalfa silage (25%) + apple pulp (75%) and 8) alfalfa silage (25%) + apple pulp (75%) + essential oil that ensiled for 90 days. Degradabilities determined using nylon bags technique with four replications. The data were analyzed in a factorial arrangement of 2×4 on a completely randomized design. At the end of 96 h of incubation, the highest amount of dry matter disappearance was observed in the treatment of alfalfa 25% and apple pulp 75% with the essential oil additive and the lowest amount was for the treatment alfalfa and essential oil additive. Adding essential oil to alfalfa silage during the preparation of silage increased the dry matter degradation rate and the effective degradation and improved nutritive value of silage. Also, the addition of apple pulp at different levels increased rapidly degradation and slowly degradation fractions and effective degradability.

The aim of this study was the molecular and bioinformatics analysis of regulatory upstream region of leptin and SIGLEC5 genes in association with production and reproduction traits in Holstein cattle. For this purpose, 300 blood samples were collected randomly and DNA was extracted. Two fragments of 251 and 406 bp from regulatory upstream regions of leptin and SIGLEC5 genes were amplified by PCR and genotyping was done by SSCP method. One sample from each banding pattern was sequenced and bioinformatics analysis were done by BioEdit and DNASIS MAX softwares. The SIGLEC5 locus was monomorphic, whereas, four banding patterns of A, B, C and D with frequencies of 0.25, 0.36, 0.22 and 0.17 were observed in leptin locus, respectively. Statistical analysis showed that leptin gene polymorphism was significantly (P<0.05) associated with milk lipid and status of parturition, so that cows with banding pattern A had the highest milk fat and cows with banding pattern D showed lowest milk fat. Also, cows with banding pattern D had the best status of parturition (easy birth) (P<0.05). The bioinformatics analysis showed 14 and nine motifs in SIGLEC5 and leptin genes, respectively. Therefore, according to the results of this study, leptin gene can be suggested to improve production and reproduction traits. In addition, complementary studies on other regions of SIGLEC5 gene to find relations between production and reproduction traits in Holstein cattle are highly recommended.

The aim of this study was to partial genome scan (chromosome 5) of Japanese quail to detect QTLs affecting growth traits based on a four-generation partial diallele cross design in Special Domestic Animals Research Center of University of Zabol. For this purpose, four strains of Wild (A), A and M of Texas (B), Italian Speckled (C) and Tuxedo (D) Japanese quails were crossed in two-strain reciprocal method and were created the first generation. Grandparents and fourth parents (18 and 36 birds, respectively) and all birds of fourth generation (315 birds) were genotyped for three microsatellite markers on chromosome 5. Also, all birds from hatch to 45 days were weighted at 5-day intervals. The QTL analysis was carried out using a regression-based interval mapping method and additive genetic model using GridQTL software. The results showed three different QTLs for hatch weight, weights at 15 and 20 days of age in 4.65, 16.03 and 15.63 cM, respectively.Therefore, if the adjacent marker information be entered in equation of breeding values estimation, it can lead to improve the reliability of prediction breeding value and finally result in genetic progress.