Ali Reza Ghiasvand; Hassan Shirzadi; Hossein Ali Ghasemi; Kamran Taherpour; Shokoufeh Hasanvand; Ali Khatibjoo
Abstract
Objective: The aim of this study was to determine the optimal arginine level in the diet of Japanese quails (Coturnix coturnix japonica) and evaluate its effects on growth performance, feed efficiency, and carcass yield using broken-line and quadratic regression models.
Method: For this purpose, a total ...
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Objective: The aim of this study was to determine the optimal arginine level in the diet of Japanese quails (Coturnix coturnix japonica) and evaluate its effects on growth performance, feed efficiency, and carcass yield using broken-line and quadratic regression models.
Method: For this purpose, a total of 600 twenty-one-day-old Japanese quail chicks were divided into five different treatments with digestible arginine levels of 0.75%, 1.00%, 1.25%, 1.50%, and 1.75%. Six replicates were used for each treatment, with 20 quails per replicate. The experimental diets were similar in all essential nutrients except for arginine. The experiment was conducted from day 21 to day 35, and during the experimental period, various performance parameters, including body weight gain, feed efficiency, and carcass yield, were measured. Additionally, the effects of different arginine levels on the chemical composition of breast and thigh meat were evaluated.
Results: The results indicated that increasing arginine levels had a significant impact on body weight gain and feed efficiency in the quails (P<0.05). Specifically, the 1.25% arginine treatment showed the greatest body weight gain and feed efficiency compared to the other treatments (P<0.05). This treatment showed a significant difference compared to the 0.75% and 1.00% treatments (P<0.05), with no significant difference compared to the 1.50% arginine treatment. No significant changes in feed intake were observed (P>0.05), indicating that greater arginine levels improved feed utilization efficiency due to increased body weight gain. To estimate the arginine requirement, both broken-line linear and quadratic regression models were employed. The broken-line linear model with a single slope identified breakpoints at 1.15% for body weight gain and 1.21% for feed efficiency. Additionally, the quadratic broken-line model predicted breakpoints at 1.30% for body weight gain and 1.29% for feed efficiency. The quadratic regression model showed that at 1.37% arginine, the greatest body weight gain was observed, and at 1.36%, the greatest feed efficiency was recorded. For carcass yield, the 1.25% arginine treatment showed the greatest carcass yield on day 35, with a significant difference compared to the 0.75% and 1.75% treatments. Both broken-line and quadratic regression models indicated that the optimal arginine level for the greatest carcass yield was approximately 1.12% and 1.26%, respectively. Additionally, the quadratic regression model predicted that the optimal level for carcass yield was 1.32% arginine. However, the chemical composition of breast and thigh meat was not affected by the arginine levels, and no significant changes in dry matter, organic matter, and ash content were observed.
Conclusions: The results of this study indicated that the use of broken-line linear and quadratic regression models are effective tools for accurately estimating the arginine requirement in the diet of Japanese quails. Based on the findings, it is recommended that the optimal arginine level for improving growth performance and carcass yield in Japanese quails was set between 1.15% and 1.37%. These findings can contribute to optimizing dietary formulations in the quail farming industry, improving production efficiency, and reducing feed costs.
Faezeh Khani; Ali Assadi-Alamouti; Behzad Khorrami
Abstract
Objective: Livestock producers in Iran face increasing challenges with forage supply due to progressively detrimental climatic changes. Due to nutrient losses during drying, and spoilage and mold during storage of fresh forage, ensiling is used to preserve and utilize forage when fresh produce is unavailable. ...
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Objective: Livestock producers in Iran face increasing challenges with forage supply due to progressively detrimental climatic changes. Due to nutrient losses during drying, and spoilage and mold during storage of fresh forage, ensiling is used to preserve and utilize forage when fresh produce is unavailable. Intercropping barley crop (Hordeum vulgare) with forage pea (Pisum arvense L.) can provide a substantial portion of the protein requirements for growing livestock and dairy cows, given its acceptable protein yield per hectare. Considering the advantages of legume-cereal forage intercropping and the widespread adoption of winter cropping for forage production nationwide, particularly in the Varamin region of Iran, optimizing the legume-cereal ratio in forage crop mixtures is essential to maximize agronomic performance, water-use efficiency, nutritional value, and suitability of the mix for animal feeding. Therefore, this study aimed to investigate the effects of different ratios of whole-crop barley to forage pea on silage fermentation quality and digestibility, and to determine the optimal mixing ratio.
Method: Whole crop barley and forage pea were harvested at specific growth stages (early dough stage for barley and mid-flowering to late flowering/early pod formation for forage pea). The experiment consisted of four treatments: 1) 100% barley silage, 2) 80% barley + 20% forage pea silage, 3) 70% barley + 30% forage pea silage, and 4) 60% barley + 40% forage pea silage, with three replicates in a completely randomized design. Ensiling was carried out in 10-liter plastic mini-silos. After 60 days of ensiling, the silos were opened and sampled for analysis of crude ash, ether extract (EE), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent insoluble nitrogen (ADIN), lignin (ADL), water-soluble carbohydrates (WSC), ammonia N and volatile fatty acids. An in vitro gas production test was used to compare treatments for gas production kinetics, and estimated digestibility, metabolisable energy, and short-chain fatty acid concentrations.
Result: With the increase in the proportion of forage pea, the dry matter content decreased while pH increased. The inclusion of forage pea in the mixture tended to increase crude protein and crude ash contents (P < 0.10). However, the values of EE, ADF, NDF, ADL, and ADIN were not affected by the forage pea (P > 0.05). Furthermore, increasing the proportion of forage pea significantly elevated the concentration of ammonia-N in the silage (P<0.05). No significant differences were observed among silages in terms of acetic, propionic, and butyric acid concentrations, with the levels of these volatile fatty acids falling within the range typically found in well-fermented silages. The treated silage containing 20% forage pea exhibited higher gas production volume, organic matter digestibility, metabolizable energy, and short-chain fatty acids than forage barley silage as the sole crop (P < 0.05).
Conclusions: Overall, the results demonstrated that mixing forage pea with whole crop barley during ensiling improved its nutritional value by enhancing CP content and reducing fiber levels, while taking advantage of barley forage, such as higher dry matter and WSC. This approach could serve as a winter-cropping strategy in semi-arid climates, improving feed quality, reducing costs, and promoting environmental sustainability. The present study suggested a 20% forage pea inclusion level for mixing with barley forage in laboratory conditions. However, this proportion should be further studied in animal trials.