Research On Animal Production

Extended Abstract
Background: The use of medicinal plants in animal feeding, particularly in finishing rations, has become an increasingly recognized strategy for improving growth performance and the overall health of livestock. One such plant, Mallow (Malva sylvestris), has gained attention for its numerous medicinal and therapeutic properties, which can have significant positive effects on rumen function, nutrient digestion, feed cost reduction, and overall production efficiency. This plant is widely grown in several provinces of Iran, especially in Khuzestan, Bushehr, and Hormozgan, and is recognized as a rich source of bioactive compounds, including flavonoids, phenolic acids, and mucilage, which are beneficial for animal health. Given the increasing use of medicinal plants as substitutes for chemical feed supplements, this study aimed to evaluate the effects of adding hydroalcoholic mallow extract to the diet of male fattening lambs on growth performance, digestibility, and rumen and blood parameters.
Methods: This research was conducted on a total of 30 male Arabic lambs with an average weight of 22 ± 2 kg and an age of 100 ± 5 days at the Animal Husbandry Research Station of the Agricultural Sciences and Natural Resources University of Khuzestan for 90 days.  The lambs were randomly assigned to three treatments, each with 10 replicates. The experimental treatments included a control group (without mallow extract) and treatments with 0.2% and 0.4% mallow extract added as a percentage of dry matter intake. The experimental diets were formulated using the Small Ruminant Nutrition System (SRNS) software and were provided to the lambs twice daily. Throughout the trial, weekly weight measurements, daily feed intake, and blood and rumen content samples were collected to assess blood and rumen parameters. Mallow extract was prepared by soaking the dried plant in 70% ethanol and was added as a supplement to the lambs' daily diets.
Results: The treatment with 0.2% mallow extract led to a significant increase in the final weight (P = 0.019), daily weight gain (P = 0.008), dry matter intake (P = 0.02), and daily feed intake (P = 0.06) compared to the other treatments. The feed intake significantly decreased in the 0.4% mallow extract treatment, despite an increase in daily weight gain. Furthermore, the highest digestibility of organic matter (P = 0.009) and crude protein was observed in the 0.2% mallow extract treatment, suggesting a positive effect of the mallow extract on improving digestive processes and nutrient absorption. Blood parameters showed that the urea nitrogen levels in blood were significantly reduced in the 0.4% mallow extract treatment (P = 0.001), which indicates an improvement in the nutritional status of the lambs. The reduction in blood urea nitrogen is directly related to enhanced nitrogen utilization in the body, which can contribute to reduced environmental pollution and improved feed efficiency. Regarding rumen fermentation parameters, a decrease in rumen fluid pH (P = 0.03) was observed in the 0.4% mallow extract treatment, which could help improve rumen conditions and volatile fatty acid production. However, no significant differences were found between treatments in terms of volatile fatty acid production (P = 0.96). The results of this study clearly show that adding mallow extract to the diet of lambs, especially at the 0.2% level, positively influenced growth performance (P = 0.008) and nutrient digestibility. The bioactive compounds present in mallow extract, particularly phenolic acids and flavonoids, can affect the rumen microbiome, improving rumen fermentation and increasing the availability of nutrients. In addition, the decrease in blood urea nitrogen levels (P = 0.001) as a result of mallow extract supplementation suggests improved nitrogen utilization in metabolic processes, which could ultimately help reduce nitrogen excretion into the environment. These findings are consistent with other studies investigating the use of plant extracts in livestock diets, which have shown similar effects on nitrogen utilization and growth performance. The decrease in rumen pH (P = 0.03) observed in the 0.4% mallow extract treatment could improve the conditions for microbial growth in the rumen, which may enhance the production of volatile fatty acids, an important source of energy for growth. The increase in the production of volatile fatty acids, particularly acetate and butyrate, may contribute to improving rumen health and digestive processes in lambs, leading to better feed utilization and overall performance. An improvement in dry matter intake and daily feed intake (P = 0.02) was observed in the 0.2% mallow extract treatment, indicating the positive effect of mallow extract in stimulating the lambs' appetite. This increase in feed intake may be attributed to the beneficial effects of the extract on digestive processes and nutrient absorption, which in turn encourages the lambs to consume more feed, enhancing their overall growth performance.
Conclusion: This study demonstrated that the addition of hydroalcoholic mallow extract to the diet of fattening lambs, particularly at the 0.2% level, improved growth performance (P = 0.008), enhanced nutrient digestibility (P = 0.009), and improved rumen fermentation (P = 0.03). Furthermore, this extract positively affected the reduction of blood urea nitrogen (P = 0.001) and improved the composition of volatile fatty acids in the rumen. The use of mallow extract, as a natural additive in livestock diets, can serve as an effective strategy for improving growth performance and overall health in lambs. Based on the results obtained, incorporating mallow extract into livestock diets can effectively enhance animal health and performance. It is recommended to conduct further research to examine the long-term effects and precise mechanisms of mallow extract on livestock, which could help refine its application in animal nutrition.