Replacement of conventional feedstuffs with inexpensive and non-conventional ingredients such as quinoa may improve animal performance and the quality of their products. Quinoa supplementation is believed to have a good nutritive value as a ruminant feed, but evidence is scarce. The present experiment aimed to evaluate the nutritive value of whole, dried quinoa plant (Chenopodium quinoa) as a feed for ruminants. In the first experiment, the in sacco technique was used to evaluate nutrient disappearance and fermentation kinetics of quinoa. In the second experiment, the in vitro gas production technique was used to evaluate diets with substitution of clover hay with quinoa at 0 (Q0), 15 (Q15), 30 (Q30), and 45% (Q45) of the diets. Proximate analysis showed that quinoa contained about 18.6% crude protein (CP) with oleic acid, arachic acid, linoleic acid, and palmitic acid as the major fatty acids. The in sacco degradability showed that the “a” fraction of dry matter (DM) was low, while the fraction “b” was high for DM and CP. Replacing clover hay with quinoa did not affect gas or methane production; however, Q30 treatment quadratically increased (P < 0.05) its production. It is concluded that quinoa can be used as a feed for ruminants and can replace clover hay up to 45% in the diet.

Protein quality plays a key role than quantity in growth, production, and reproduction of ruminants. Application of high concentration of dietary crude protein (CP) did not balance the proportion of these limiting amino acids (AA) at duodenal digesta of high producing dairy cow. Thus, dietary supplementation of rumen-protected AA is recommended to sustain the physiological, productive, and reproductive performance of ruminants. Poor metabolism of high CP diets in rumen excretes excessive nitrogen (N) through urine and feces in the environment. This excretion is usually in the form of nitrous oxide, nitric oxide, nitrate, and ammonia. In addition to producing gases like methane, hydrogen carbon dioxide pollutes and has a potentially negative impact on air, soil, and water quality. Data specify that supplementation of top-limiting AA methionine and lysine (Met + Lys) in ruminants’ ration is one of the best approaches to enhance the utilization of feed protein and alleviate negative biohazards of CP in ruminants’ ration. In conclusion, many in vivo and in vitro studies were reviewed and reported that low dietary CP with supplemental rumen-protected AA (Met + Lys) showed a good ability to reduce N losses or NH₃. Also, it helps in declining gases emission and decreasing soil or water contamination without negative impacts on animal performance. Finally, further studies are needed on genetic and molecular basis to explain the impact of Met + Lys supplementation on co-occurrence patterns of microbiome of rumen which shine new light on bacteria, methanogen, and protozoal interaction in ruminants.

Water represents 71% of all earth area and about 97% of this water is salty water. So, only 3% of the overall world water quantity is freshwater. Human can benefit only from 1% of this water and the remaining 2% freeze at both poles of earth. Therefore, it is important to preserve the freshwater through increasing the plants consuming salty water. The future prosperity of feed resources in arid and semi-arid countries depends on economic use of alternative resources that have been marginalized for long periods of time, such as halophytic plants, which are one such potential future resource. Halophyte plants can grow in high salinity water and soil and to some extent during drought. The growth of these plants depends on the contact of the salted water with plant roots as in semi-desert saline water, mangrove swamps, marshes, and seashores. Halophyte plants need high levels of sodium chloride in the soil water for growth, and the soil water must also contain high levels of salts, as sodium hydroxide or magnesium sulfate. There are many uses for halophyte plants, including feed for animals, vegetables, drugs, sand dune stabilizers, wind shelter, soil cover, wetland cultivation, laundry detergents, and paper production. This paper will focus on the use of halophytes as a feed additive for animals. In spite of the good nutritional value of halophytes, some anti-nutritional factors as nitrates, nitrite complexes, tannins, glycosides, phenolic compounds, saponins, oxalates, and alkaloids may be present in some of them. The presence of such anti-nutritional agents makes halophytes unpalatable to animals, which tends to reduce feed intake and nutrient use. Therefore, the negative effects of these plants on animal performance are the only objection against using halophytes in animal feed diets. This review article highlights the beneficial impact of considering halophytes in animal feeding on saving freshwater and illustrates its nutritive value for livestock from different aspects.