Abstract: [Objective] To evaluate the safety and nutritional value of animal-derived protein hydrolysate prepared from meat and bone meal of disease-induced dead animals. [Methods] Meat and bone meal from different batches was processed through high-temperature and high-pressure treatment, degreasing, acid hydrolysis, distillative acid removal, neutralization and decolorization, concentration, and drying to collect animal-derived protein hydrolysate. The nutritional components （crude protein, crude fat, crude fiber, and protein digestibility, etc.）, mineral elements （calcium, total phosphorus, copper, iron, zinc, etc.）, heavy metals （arsenic, chromium, mercury, etc.）, prohibited drugs and antibiotics （clenbuterol, sulfonamides, quinolones, etc.）, microorganisms （Escherichia coli, Salmonella, etc.）, mycotoxins （vomitoxin, aflatoxin B₁, etc.）, and nucleic acids of major porcine pathogens （African swine fever virus, porcine reproductive and respiratory syndrome virus, etc.） were detected. Twenty-four healthy Duroc × Landrace × Yorkshire weaned piglets of similar age and body weight were selected and randomly divided into three groups. The control group was fed a basal diet, while experimental groups 1 and 2 were fed the basal diet supplemented with 0.1% and 0.5% animal-derived protein hydrolysate, respectively, for 35 days. Growth performance, diarrhea incidence, and serum immune, antioxidant, and biochemical parameters were measured. [Results] The animal-derived protein hydrolysate had a dry matter content of 94.04% and a crude protein content of 68.74%, with crude ash was rich in multiple mineral elements, including calcium, phosphorus, and iron exceeding 1 g/kg, and other trace elements exceeding 1 mg/kg. In terms of safety, the heavy metal mercury was not detected, and lead, cadmium, chromium, and total arsenic levels were below 1 mg/kg. No residues of prohibited drugs, harmful microorganisms, or nucleic acids of common porcine viruses were detected. Deoxynivalenol was detected at only 0.31 mg/kg, while other toxins were absent. The total bacterial count was 809 CFU/g, compliant with the Feed Hygiene Standard （GB 13078—2017）. In the weaned piglet trial, compared to the control group, diets supplemented with animal-derived protein hydrolysate significantly （P<0.05） increased average daily gain, significantly （P<0.05） reduced feed-to-gain ratio, and highly significantly （P<0.01） decreased diarrhea incidence. Additionally, it significantly （P<0.05） increased serum total protein and immunoglobulin A levels, highly significantly （P<0.01） increased immunoglobulin G levels, and significantly （P<0.05） enhanced the activities of glutathione peroxidase （GSH-Px）, superoxide dismutase （SOD）, and total antioxidant capacity （T-AOC） in plasma. [Conclusion] The animal-derived protein hydrolysate exhibits high safety and nutritional value, with the ability to modulate the body′s immune function.

Key words: meat and bone residue, animal-derived protein hydrolysate, nutritional value, safety