JWSS - Journal of Water and Soil Science

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Feed shortage is one of the most important characteristics of Iranian livestock industry. Therefore, the utilization of agricultural by-products in animal nutrition, especially for fattening animals, is of great importance. In order to study the effect of the four rations containing various levels of tallow (0, 2.5, 5, and 7.5%), on the performance of male Holstein calves (MHC), responding to the above treatments 1, 2, 3 and 4, twenty four MHC (191±32.1 kg) at age 6-7 months-old in a completely randomized design were used. The calves were fed individually for 195 days ad libitum.

Average daily gains (ADG) of the MHC fed diets 1, 2, 3 and 4 were 1.56, 1.61, 1.69 and 1.75 kg (P<0.05), respectively. Feed conversions (as DM) were 4.63, 4.31, 41.2 and 3.98 (P<0.05), respectively. Added tallow to the ration did not affect carcass, empty body weight (EBW), but increased warm carcass weight (P<0.05). The dietary treatments did not increase digestibility (D) of dry matter organic matter, crude protein and gross energy either, but decreased D of neutral detergent fiber and increased apparent crude fat (P<0.05).

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In order to determine the most suitable cultivar and N level based on yield and silage value of forage sorghum, an experiment was conducted in summer 1995. The experiment was arranged in a split-plot design with four replications. Two levels of N (300, 500 Kg/ha urea) were the main plots and the subplots were three sorghum hybrids (Sugar graze, Super dan and Speed feed). Seeds were hand sown on June 29 with an inter row space of 50 cm and a final density of 20 plant/m².

The results showed that when the N rate increased, forage yields and percent of protein in forage and silage increased. Also panicle dry weight increased at anthesis. The N rate had no significant effect on other traits. A significant difference was observed among hybrids for all characteristics measured. Sugar graze with a bigger stem diameter was taller and produced higher number of leaves. At anthesis, plant leaf and stem dry weight was also highest for Sugar graze however, the highest panicle dry weight belonged to Speed feed. There was a significant interaction between hybrids and N levels for dry matter production. The percent of leaf, stem and panicle dry matter was highest in sugar graze, Super dan and Speed feed, respectively. The Sugar graze produced the highest forage and dry matter yield. This hybrid produced 30 ton/ha of dry matter and 97 ton/ha of forage, respectively.

 Furthermore, this cultivar had the highest percent of forage crude protein (7.45%) and the least percent of forage crude fiber (25.12%). Ensiling caused a decrease in percentage of crude protein and an increase in crude fiber. The Sugar graze and Speed feed had the highest and lowest dry matter digestibility, respectively. Based on the results obtained from this study, Sugar graze was found to be the most suitable hybrid due to its highest forage and dry matter yield and better silage quality. Higher N rate (500 kg/ha) is also recommended for higher forage yield and higher percentage of protein.

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Effect of supplemental phytase on phosphorus and protein utilization and performance of broiler chickens fed on eight different wheat varieties were evaluated. The phytate contents of wheat varieties were determined. In a completely randomized design with a 8*3 factorial arrangement, 384 day-old commercial male brioler chicks (HubbardPeterson) were divided into 96 groups, four chicks per group. Each of the 24 experimental diets (eight varieties) and three levels of phytase (zero, 500 and 1000 FTU/Kg) were given to four replicates for a period of 21 days. At 21 days of age, chickens of each replicate were weighed and killed by cervical dislocation. Ileal contents were collected and analyzed for P, N, phytate and chromic oxide. Left tibia of two birds in each replicate were removed, pooled and stored at -20^oC for bone ash determination. There was a significant (P<0.03) difference in phytate contents between different wheat varieties. Effect of wheat varieties on body weight, feed conversion ratio and bone ash was significant (P<0.05). Added phytase improved body weight, feed consumption, feed conversion ratio and bone ash significantly (P<0.05). Phytase added at 500 FTU/Kg, improved protein digestibility significantly (P<0.01), but increasing the supplement to 1000 FTU/Kg had no further effect. Difference between enzyme levels (500 and 1000 FTU/Kg) was not significant regarding body weight, feed consumption, feed conversion ratio and bone ash. Overall addition of phytase to the diets containing wheat caused an improvement in performance, protein digestibility, and phytase phosphorus utilization in broiler chickens, and can, therefore, be used in diets to reduce feed cost and environmental problems.

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The effect of adding two urea levels (0.5 and 0.75% on fresh basis) to whole-crop barley (WCB) on chemical compositon and digestibility in Ghezel rams was studied. The effect of including these silages in the ration of fattening Ghezel and Mehraban rams was also investigated. Urea supplementation of WCB silage resulted in an increase in pH, total nitrogen level, and ammonia-nitrogen concentrations (P<0.05). Apparent digestibility coefficients of dry matter, organic matter, acid detergent fiber, and neutral detergent fiber of WCB silage were not affected by urea treatment (P>0.05), but apparent digestibility coefficient of total nitrogen was higher for 0.5% urea-WCB silage. Apparent digestibility coefficients of total nitrogen and nitrogen balance were higher for 0.5% urea-WCB silage than for 0.75% urea-WCB silage, but the differences were not significant. Ruminal fluid pH at 2.5 h, and ammonia-nitrogen concentration at 4 h post-feeding were higher for 0.75% urea-WCB silage than for 0.5% urea-WCB silage (P<0.05). BUN levels (<20 mg per dl) in sheep fed with a mixture of alfalfa hay and silages were not affected by the treatment. The potential and effective degradabilities of dry matter and crude protein were higher for 0.75% urea-WCB silage. Feed performance and carcass characteristics were not significantly different amongst diets. The results showed that urea supplementation at 0.75% fresh basis, at the time of ensiling, may have a beneficial effect on feeding value of WCB silage.

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The aim of this research was to study the effect of treatment with oyster mushroom (Pleurotus sajor-caju) on digestibility of Glycyrrhiza glabra L. pulp. Pleurotus sajor-caju was inoculated on sterilized wheat grains. Two weeks after growth at 25 °C it was added to the sterilized Glycyrrhiza glabra L. pulp in nylon bags. After two weeks (at 25 °C), mycelia grew on the pulp and were used for treatment. Digestibility coefficients were measured in 12 Ghezel rams. Dry matter, crude protein (CP) and nitrogen free extract (NFE) increased, but ash content, cell wall (NDF) and lignin (ADL) decreased significantly in fungal-treated as compared with non-treated pulps. Crude fiber (CF) and ADF contents were not significantly affected by the treatment. There was a tendency for crude fat (EE ether extract) to decrease by fungal treatment (p=0.08). Mean dry matter intake and digestibility coefficient of dry matter were higher in sheep which were fed the fungal-treated pulp compared with the control group. Digestibility coefficients of CP, CF, organic matter (OM), EE, NFE, NDF, ADF and ADL were significantly greater in fungal-treated pulp than in control group. Treatment with P. sajor-caju increased the nutritive value and digestibility of Glycyrrhiza glabra L. pulp (P<0.05), but culture of this fungus was not possible on non-sterilized pulp, which hinders its field application.

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In a completely randomized design with 3×5 factorial arrangement, the metabolizable energy and nutrients digestibility of three varieties of sorghum grains (low, medium and high tannin) with and without supplemental phytase were determined and was compared with corn and wheat. Three varieties of sorghum were selected from the 36 varieties according to their tannin content and were grown togther with corn and wheat under the same environmental conditions. Supplemental phytase was added at three levels (0.0, 500 and 1000 FTU/kg) to each grain. The metabolizable energy (ME) and nutrients digestibilities were determined by the mature male Leghorn with the method of Sibbald. The results indicated that different grains had different ME, apparent and true digestibilities regarding dry matter, nitrogen and phosphorus. Medium tannin sorghum had the highest apparent and true metabolizable (AME and TME) energy, whereas the high tannin sorghum showed the lowest AME and TME. The apparent and true dry matter digestibilities of corn was more than the other grains (P<0.001). Medium tannin sorghum had the highest apparent and true nitrogen digestibilies than the other two varieties (P<0.001). Difference between tested grains regarding apparent and true phosphorus digestibilities were not significant. All measured criteria were the lowest for the high tannin sorghum. Adding 500 FTU/Kg phytase caused an improvement (P<0.001) in AME, apparent and true dry matter digestibilities and true nitrogen digestibility. Although added phytase improved apparent and true phosphorus digestibilities and true nitrogen digestibility, but the differences were not significant. The differences between 500 and 1000 units phytase was not significant and the results indicated that 500 FTU/Kg phytase was sufficient to improve the nutritional value of grains under study.

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The nutritive value of the annual alfalfa (Medicago rigidulla, Medicago polymorpha and Medicago scutellata) species harvested at flowering stage was assessed by chemical composition, in vitro dry matter and nitrogen digestibility, in sacco dry matter and nitrogen degradation (0, 8, 12, 24, 48 and 72 h) and palatability (short-term intake rate, STIR) methods. Mean values of the chemical analysis results (%) for M. rigidulla, M. polymorpha and M. scutellata respectively were as follows: OM 85.1, 86.1 and 86.9 CP 25.1, 23.8 and 15.6 NDF 23.2, 24.8 and 30.0 ADF 18.3, 19.9 and 24.0 ADIN 0.36, 0.11 and 0.22 calcium 1.4, 1.3 and 1.2 phosphorus 0.23, 0.28 and 0.24 potassium 1.5, 1.5 and 1.4. The digestibilities of the DM and OM for M. rigidulla were 0.82 and 0.79 M. polymorpha 0.83.5 and 0.80 M. scutellata 0.75 and 0.69, respectively. The degradabilities of DM and CP at outflow rate of 0.05 for M. rigidulla were 0.72 and 0.55 M. polymorpha 0.71 and 0.57 M. scutellata 0.63 and 0.58, respectively. Finally, the palatabilities (using short-term intake rate method) for M. rigidulla, M. polymorpha and M. scutellata species were 13.6, 12.8 and 11.3 (g DM/min) respectively. According to the methods used, the descending ranking order (high to low) of these species on the basis of their nutritional value was M.rigidulla, M.polymorpha and M.scutellata.

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This experiment was carried out to determine the nutritional value and the effect of different levels of tomato seed and pomace on performance of broilers. Corn grains and soyabean meals were replaced by tomato seed at levels of 6, 12 and 18 % and tomato pomace at levels of 3, 9 and 12 %. At first, the metabolizable energy of tomato seed and pomace was determined by the Sibbald method. In this experiment, 504 commercial broiler chicks (Ross 308) were used for 8 weeks (from 7 to 56 days old ) in a completely randomized design in 7 treatments with 4 replications per treatment. After 21 days, protein digestibility of the ration in illeum was determined. Apparent metabolizable energy was 3394 kcal/kg for seed and 2329 kcal/kg for pomace and crude protein was 31, 22.7, respectively . The result showed that body weight, protein digestibility of rations in illeum and carcass characteristics were not significantly different . Best energy and protein conversion efficiencies were obtained at the level of 6 % seed and 9 % pomace, that were not significantly different from control treatment. Cheeks fed with seed and 12% tomato pomace had significantly (p<0.5) higher feed intake than control group.The difference between diets containing 6% seed and 3% pomace and control group was not significant regarding feed conversion ratio.

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This experiment was conducted to determinate the effects of different levels of Amet protein binder (0, 1.5, 3, 4.5 and 6) in substitution for fish meal on performance and digestibility of nutrients. This study used 400 broiler chickens (Ross strain) with 5 treatments of 4 replications in a completely randomized design. Weight gain, feed consumption, and feed conversion ratio were determined at the end of each phase of the experiment. In addition, the digestibility of nutrients and apparent metabolizable energy (AMEn) of the whole diets were measured by sampling excreta. The results showed that levels of 4.5 and 6% of Amet significantly decreased feed consumption (P< 0.01). Feed consumption was higher for 1.5, 0(control), and 3% Amet in diets, respectively. At the starting phase, 1.5% Amet treatment improved feed conversion ratio (P<0.01). The treatments 6% and 4.5% Amet increased feed conversion ratio in all phases of experiment and the final phase. Percentages of abdominal fat were not significantly affected by treatments. Replacement of different levels of Amet except the treatment 6% had no significant effect on percentage of carcass. The level of 1.5% Amet versus control significantly increased AMEn (P<0.01). It seems that the inclusion of 1.5% Amet binder in the diet can positively affect performance and AMEn of diet in broiler chickens.

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Eight multiparous Holstein dairy cows with 634±44 BW, 57±6 DIM, and 46.7±3.1 kg daily milk yield were assigned to a duplicated 4×4 Latin square design for 21-day periods (adaptation, 14d sample collection, 7d). The treatment diets were: 1) no pistachio by-product (control), 2) 5% of pistachio by-product, 3) 10% pistachio by-product and 4) 15% pistachio by-product. Corn silage in control diet was replaced with pistachio by-product. The blood metabolites (2h after feeding), DMI, daily milk yield and milk compositions were not affected by the treatment diets. The economically corrected milk (ECM) and fat corrected milk (FCM) were decreased linearly by increasing pistachio by-product in the diet (P<0.1). By increasing the by-product level in the diet, digestibility of DM, OM, NDF and ADF were decreased linearly (P<0.05). Daily rumination and chewing activity alone or per DMI, NDFI or ADFI were linearly decreased when the by-product level increased in the diet (P<0.1). The results showed that the pistachio by-product does not seem to be suitable for complete replacing of the roughages in the diet and it can be used as a part of forage in the diet up to 10% of DMI.