مجله تحقیقات دام و طیور
سال دوم شماره 1 (1392)

This experiment was conducted to evaluate the effects of chromium supplementation on performance, blood parameters, lipid oxidation of longissimusdorsi muscle (LDM) and tissue chromium in Mahabadi goat kids. Thirty-two male kids (average initial BW of 22 ± 2 kg, 4-5mo) were used in a completely randomized design with four treatments: 1) control (without Cr suppl.), 2) 0.5 mg Cr suppl., 3) 1 mg Cr suppl. and 4) 1.5 mg Cr suppl. as Cr-Met/animal/d. Diets were the same and experimental period was 94 days. Animals were kept in individual pens with self-mangers. Kids were weighed at 21 day intervals and slaughtered at the end of the trial. Dry matter intake and average daily gain were not affected by the chromium supplementation but, feed conversion ratio (FCR) improved in the 1.5 mg Cr/d. Maximum blood glucose concentration during an epinephrine challenge test decreased in the 1.5 mg Cr/d group. However, blood insulin and cortisol remained unaffected. TBARs values of the LDM significantly increased as their storage time increased from 1 to 2 months (P<0.05). It was also found that increasing dietary chromium supplementation, especially 1.5 mg Cr/animal/d, significantly decreased lipid oxidation and TBARs value of LDM after 2 months storage (P<0.05). On the first month of storage, dietary Cr supplement not significantly tended to decrease lipid oxidation of LDM (P<0.1). Chromium contents in plasma, liver, kidney and LDM increased significantly with the addition of Cr-Met in diet (P<0.05). The results of this experiment showed that supplemental Cr improved performance, decreased TBARs value of LDM and increased chromium contents in blood and tissues of Mahabadi goat kids.

The objective of this study was to determine the effect of inclusion of polyethylene glycol (PEG, MV= 6000) on gas production kinetics, organic matter digestibility (OMD), the metabolisable energy (ME) and dry matter (DM) disappearance of pistachio epicarp by in vitro method. PEG used at rates 0, 300 and 600 mg/300g DM. Gas production volume and the amount of DM disappearance was determined after 2, 4, 6, 8, 12, 16, 24, 36, 48, 72 and 96 h of incubation. The data was analyzed using completely randomized design. Addition of PEG resulted in an increased gas production at all incubation times than control and this process continued until final hours of incubation (P<0.05). Addition of PEG resulted in increased ME and OMD than control (P<0.05). In vitro DM disappearance after 48 h incubation PEG at level 2 g had the highest DM disappearance amount (P<0.05). This study showed that inclusion of PEG demonstrated the negative effect of tannins in pistachio epicarp on digestibility.

The aim of this study was to determine the proportion of Lactobacillus strains liquid solution which was supposed to be added to the surface of restaurant waste (RW). To do so, each of different levels (2, 3, 5 and 7 ml) of liquid solution containing selected Lactobacillus strains (L. acidophilus, L. reuteri, L. plantarum and L. casei) was added to 1 kg of homogeneous and uniform waste with three replicates. The results of the first experiment indicated that adding 5 ml of liquid solution to 1 kg of the waste had the highest survival and economic justification. The second experiment evaluated the effect of 5 ml level of liquid solution on the amount of RW nutrients. Five treatments (four Lactobacillus treatments and one control treatment) were added to 1 kg of waste with five replicates. Finding of the experiment related to RW nutrients showed that microbial processing by Lactobacillus treatments caused a significant improvement as compared to the control treatment (P<0.05). Among the strains used L. acidophilus had the highest mean amount of crude protein (CP), ether extract (EE), dry matter (DM) and gross energy (GE) with respectively 21.40%, 19.91%, 41.02% and 4872.61 kcal/kg and it had the lowest amount of ash with 3.67% compared with the other strains. Due to fluctuations in the chemical composition of each meal and to resolve the ambiguity that whether the change in chemical composition of the waste is influenced by days and weeks or not, an individual experiment was conducted and the chemical composition of the meals was separately analyzed during 4 weeks. The results of the experiment demonstrated that there was not a close relationship between the weeks and the mean chemical compositions of the raw waste. Average CP, DM, EE, ash and GE for all days of the week were 18.74% 38.46% 18.67% 4.09% and 4497.65 kcal/kg, respectively. These results clearly showed that the numbers gained from sampling and the uniform mixtures of the waste were not significantly different. The amounts of CP, DM, EE, ash and GE within the uniform mixture were 18.87%, 38.78%, 18.84%, 4.12% and 4507.33 kcal/kg, respectively. The economic calculation of using RW showed that its use in poultry diet is permitted and it is more economical.

This experiment was conducted to evaluate the effect of different levels of Silybum marianum seed on performance and some egg characteristics such as egg shell weight, shell thickness, yolk index, yolk color and Haugh unit of laying hens. The experiment was undertaken on hay-line strain (w-36) from 32 to 42 weeks, using a completely randomized design with three treatments, four replicates and four hens in each replicate. The experimental diets were: 1- basal diet (control), 2- basal diet + 1% Silybum marianum seed and 3- basal diet + 2% Silybum marianum seed. The results showed that through performance trait, the average egg weight in treatment having 2% Silybum marianum had a significant increase compared to the control treatment (P<0.05). Although egg production increased in treatments containing Silybum marianum, this increase was not statistically significant. Egg mass in the treatment having 2% Silybum marianum significantly increased compared to the control (P<0.05). Feed intake and feed conversion ratio decreased in the treatments containing Silybum marianum but was not statistically significant. Between egg characteristics, yolk color in the first period was significantly increased by 1% Silybum marianum (P<0.05). Also Haugh unit increased in all treatments containing Silybum marianum, but this increase was significant only in the second period (P<0.05). Based on the results obtained from this research, the use of milk thistle seeds in the diet of laying hens had beneficial effects on performance and egg characteristics such as the Haugh unit in laying hens.

This experiment carried out to determination of the chemical composition and nutritional value of sorghum silage ensiled by bucket or plastic bag. The chopped forage were ensiled in mini-silo for 81 days. To measurement of the degradation characteristics of dry matter, crude protein and NDF was used nylon bags and gas test method. The results showed that the crude protein and ammonia nitrogen in silage plastic was significantly greater than the silage bucket (P<0.05). Crude fat, ash, total and condensed tannins, NDF, ADF and pH were not significant difference between two treatment. The results of the degradation of dry matter, crude protein and NDF showed that part of rapid degradation (a) of crude protein and NDF of the silage buckets was significantly higher than plastic silage (P<0.05). The values of other parameters degradation, there were no significant differences in between the treatment. Results of gas test showed no significant difference between gas produced during the incubation different times. The overall results showed that the value nutritional of silages were similar in two methods.

Forage plants have different qualities at different times and places. Determination of rangeland forage quality is the main factor for the proper management of rangeland. This study was performed to determine and compare some properties of nutritional value in two rangeland species (Prangos ferulaceae and Dorema aucheri) in three phenological stages (vegetative growth, flowering and seeding) in the summer rangelands of Kohgiloyeh. The experiment was carried out in a completely randomized design with three treatments (three phenological stages) and four replicates for each treatment. Samples were collected, dried and milled and then analyzed for determination of crude protein (CP), ash, phosphorus (P), calcium (Ca) and gross energy (GE). SAS software and Tukey test were used for statistical analysis and means comparison. The results indicated that the amount of crude protein, ether extract, ash, calcium and phosphorus of both species were greater in the growth stage than the other phenological stages. Crude protein, ash and calcium contents were significantly different (P<0.05) in two plants at all of the three phenology stages. The results showed that the highest forage quality was found in both species at the vegetative growth stages.

A study was conducted to investigate the effects of different dietary levels of Cumin seed on internal and external egg quality characteristics and some blood parameters in Japanese quail. Experiment was conducted in a completely randomized design with 288 pieces of Japanese quail egg English white with six treatments, four replicates and 12 quails per each for eight weeks from 7 to 15 weeks of age. Diets consisted of six levels, 0 (no Cumin seed), 0.5, 1, 1.5, 2 and 2.5 percent of cumin seeds. The results showed that the different levels of Cumin seeds in eggshell softness, yolk color, shell weight and shell thickness were not significantly affected. However statistically significant differences were observed in Haugh unit score (P<0.05). The highest levels Haugh unit score were resulted by using the control diet. The diet contained 1.5 percent of Cumin seed decreased significantly Haugh unit of the quail eggs (P<0.05). The effects of different dietary levels of Cumin seed on average concentration of serum blood cholesterol, triglycerides, HDL and glucose were not statistically significant. The result of this experiment indicated that 1.5 % of Cumin seed increased Haugh unit but there was not any effect on the other characters.

The effect of feeding barley-diets supplemented with three commercial enzymes containing xylanase and β-glucanase activities based on matrix value were investigated on performance and gastrointestinal tract size of broiler chicks. A total of 260-day-old male broiler chicks (Ross 308) were allocated to five treatment groups, with four replicates per treatment group and 13 birds per replicate pen. All data were analyzed in a randomized complete design. In the entire period, adding all enzymes to barley-based diet significantly (P<0.05) increased average daily feed intake (ADFI) in comparison with barley and corn-based diet without enzyme. Generally, from 0 to 42 d of age, body weight gain (BWG) and feed conversion ratio (FCR) were significantly (P<0.05) improved when diets containing enzymes as compared to barley-based diet without enzyme. At 43 of days of age, relative weight of pancreas and relative length and weight of duodenum, jejunum, ileum and cecum significantly decreased by addition of all enzymes compared to barley and corn-based diet. Relative weight of liver and spleen were not significantly affected by enzyme. However, the relative weight of the abdominal fat were significantly (P<0.05) increased by enzyme addition. In general, it seems that use of enzyme based on matrix value can improve performance of birds that fed barley-based diet. According to the results, feeding enzymes A, C and corn-based diet similarly improved FCR, but by considering final body weight broiler, enzyme A showed the best performance among enzymes used in this experiment.