BACKGROUND: The use of additives, such as medicinal plants, may result in improved digestion and fermentation and consequently, animal production. OBJECTIVES: The present experiment was conducted to determine the most appropriate amount of Ziziphora cliniopodiodes plant to be utilized in lamb diet and its effect on digestibility, fermentation, growth performance, blood, and quality of carcass and meat. METHODS: Different amounts of Ziziphora cliniopodiodes (0, 0.2, 0.4, 0.6, 0.8, 1 %) were added to diet of lambs. The best diet was selected based on gas production method and fed to male lambs with an average weight of 41 ± 2 kg in a completely randomized design with three treatments and six replications. The selected diets for feeding lambs included: control diet (Ziziphora cliniopodiodes) and control diet supplemented with 0.2 or 0.4 % Ziziphora cliniopodiodes. Feed intake, digestibility of nutrients, fattening performance, blood and rumen fermentation parameters, protozoan population, and certain meat quality indexes were measured. At the end of the experiment, the carcass traits were studied. RESULTS: The obtained results herein revealed that the potential of gas production, partitioning factor, truly degradable organic matter, dry matter intake, apparent digestibility of dry matter, organic matter, crude protein, neutral detergent fiber, acid detergent fiber, glucose, cholesterol, triglyceride, blood urea nitrogen, and protozoa population were not affected by the experimental diets. There was a significant difference among the experimental diets for daily weight gain, the total weight gain of lambs, and microbial biomass production. The highest records belonged to the diet containing 0.2 % Ziziphora cliniopodiodes. Antioxidant characteristics, colorimetric indices, and pH of meat were not affected by the applied treatments. CONCLUSIONS: In general, according to livestock experiments, the best amount of Ziziphora cliniopodiodes to be employed was 0.2 %, which improved certain fermentative and performance traits.

BACKGROUND: Identifying the potential of livestock and forage plants of each region is a way to compensate the lack of forage, and efficient use of edible resources of the country. Milk Thistle is a medicinal plant which may be used as fodder for native livestock of Khuzestan Province. OBJECTIVES: The purpose of this research was to study  the effects of different levels of Milk Thistle on rumen fungi and whole rumen microorganisms (WRM) of Khuzestan buffalo, with diets containing grains with different degradation rate (barley and maize). METHODS: The impact of diets containing different levels of Milk Thistle (0, 100 and 200 g per kg DM) on rumen fungi and WRM of buffalo was measured by different techniques. RESULTS: Potential and rate of gas production from experimental diets by WRM were not significantly different. This parameters by buffalo rumen fungi were significantly differed and increased in diets containing Milk Thistle (p<0.05). Adding Milk Thistle in the barley-based diet increased dry matter and NDF digestibility numerically while in the corn-based diet dry matter and NDF digestibility was slightly reduced. In the SRFCM, NDF digestibility, in both basal diets in 9 days and during total period was affected by diets containing Milk Thistle and decreased NDF digestibility with increasing levels of Milk Thistle (p<0.05). Regardless of the type of basal diet, digestibility of NDF (p<0.05) and dry matter (p>0.05) for day 6, were increased with increasing the amount of Milk Thistle. CONCLUSIONS: In general, the use of Milk Thistle did not have negative effect on microorganisms and digestion of nutrients by them. Therefore, results suggest that Milk Thistle could be used up to 20 percentage in buffalo diet without any negative effect on digestion and fermentation characteristics by total microorganisms and fungi.