Relationship between fecal Color and Feed composition in Pigs

Under normal circumstances, the color of pig feces changes with the composition of feed materials. There are several kinds of feed materials, which have a significant effect on the color of feces. First, green feed, such as grass powder, beating forage, etc., pig feces are dark brown yellow, relatively loose; one is blood powder, blood cell protein or high iron feed, pig feces are brown and black after eating, and the depth is related to the content of blood powder or iron in the feed; first, high copper, that is, copper sulfate above 200ppm is added to the feed, and the feces excreted after pig food are pure black and relatively dense. First, with the addition of additives such as sodium humate, the feces of pigs are also black, but they are lighter than those of pigs fed with high copper diets. So in the implementation of document 1224, from the perspective of pig nutrition, which is the most suitable? The improvement effect on feed intake and growth rate is the most obvious. If you are interested, come in and discuss it. The color of feces doesn't matter. The important thing is not to hurt the pig's internal organs and not to affect people! The color of feces does not reflect the quality of the feed. The addition of high copper, especially sodium humate, can only increase the cost.-- for the first problem, it does not harm the viscera of pigs, which has the most to do with drug feed additives and therapeutic drugs. Whether it is high copper or high iron in feed, the intestinal absorption of pigs is limited. It is generally converted into sulfides (ferrous sulfide, copper sulfide) and discharged from the body. As for the second question, it is much more complicated. For example, high copper and high iron faeces are excreted into the environment and used as fertilizers, which has a certain toxic effect on crops and will lead to a decline in crop yields. While some drugs are said to not be degraded in pigs, it is not known whether direct discharge without treatment will lead to the emergence of a large number of drug-resistant strains or lead to genetic variation in bacteria.