Antibacterial peptides were isolated and purified from whey proteins of camel milk (CaW) and cow milk (CoW) and their antimicrobial activities were studied. The whey proteins were hydrolyzed using trypsin, and the degree of hydrolysis was identified by gel electrophoresis. The whey hydrolysate (WH) was purified using ultrafiltration and Dextran gel chromatography to obtain small peptides with antibacterial activity. The effect of the antimicrobial peptides on the morphology of bacterial strains was investigated using transmission electron microscopy. Their amino acid composition and antimicrobial activities were then determined. Polypeptides CaWH-III (<3 kDa) and CoWH-III (<3 kDa) had the strongest antibacterial activity. Both Fr.A2 (CaWH-Ⅲ’s fraction 2) and Fr.B1 (CoWH-Ⅲ’s fraction 1) had antibacterial effects toward Escherichia coli and Staphylococcus aureus, with minimum antimicrobial mass concentrations of 65 mg/mL and 130 mg/mL for Fr.A2, and 130 mg/mL and 130 mg/mL for Fr.B1, respectively. The highly active antimicrobial peptides had high amounts of alkaline amino acids (28.13% in camel milk Fr.A2 and 25.07% in the cow milk Fr.B1) and hydrophobic amino acids. (51.29% in camel milk Fr.A2 and 57.69% in the cow milk Fr.B1). This results showed that hydrolysis of CaW and CoW using trypsin produced a variety of effective antimicrobial peptides against selected pathogens, and the antibacterial activity of camel milk whey was slightly higher than that of cow milk whey.

Camel meat could have health benefits for human consumers due to its nutritional value. The influence of age and muscle type on the chemical composition and quality characteristics of Bactrian camel meat was examined in the present study. Samples of the Longissimus thoracic (LT), Semitendinosus (ST), and Psoas major (PM) muscles were collected from a total of fifteen male camels in three different age groups (3–4 years, 6–7 years, and 9–10 years). The younger camels exhibited higher values of moisture, polyunsaturated fatty acids, ultimate pH, cooking loss, and lightness, but lower fat, shear force, and redness values compared to meat collected from older camels. The LT muscle had higher fat and color parameters (lightness, redness, yellowness) but lower shear force values than the ST and PM muscles (p < 0.05). The ST muscles had a higher content of n-6 polyunsaturated fatty acids and n-3 polyunsaturated fatty acids but lower cooking loss values than the LT and PM muscles. These results indicated that younger camels provide better meat quality traits than older camels. The results of the present study will improve the marketing of Bactrian camel meat products and will provide more information about the most suitable muscles and the optimal slaughter age.

Bactrian camel (Camelus bactrianus) meat, as a product of national geographical indication, is mainly produced in the northwest regions of China. This study systematically evaluated the edible quality, nutritional quality, and carcinogenic substances of Bactrian camel meat using different heating times in four thermal processing methods (steaming, boiling, frying, and microwaving). Compared with the control group (uncooked), the thermal processing of meat demonstrated lower redness and moisture content; higher shear force values and protein, fat, and ash contents; and sharply increased the levels of amino acids and fatty acids. The moisture content of the fried and microwave-treated meat was significantly lower than that of the steamed and boiled meat (p < 0.05). Steamed meat was higher in protein but had a lower fat content than the other three processing methods (p < 0.05). Compared with frying and microwaving, meat from steaming and boiling showed higher levels of essential amino acids and lower shear force values. However, the smoke generated during frying led to the formation of large amounts of polycyclic aromatic hydrocarbons (PAHs) and nitrites, and the levels of these substances increased with heating time. In addition, with the extension of the heating time, the shear force of the meat also increased gradually (p < 0.05). In summary, steaming and boiling were proven to be suitable processing methods for preserving better nutritional values while delivering less carcinogenic risk. With our results, we have established a nutritional database for Bactrian camel meat, providing a reference for selecting a suitable thermal processing method.

Bactrian camels (Camelus bactrianus) are one of the few large livestock species that can survive in the Gobi Desert. Animal immunity and disease resistance are related to hematological traits, which are also associated with tolerance observed in Bactrian camels. However, no genome-wide association studies have examined the genetic mechanism of the immune capability of Bactrian camels. In the present study, we used genotyping-by-sequencing data generated from 366 Bactrian camel accessions to perform a genome-wide association study for 17 hematological traits. Of the 256,616 single-nucleotide polymorphisms (SNPs) obtained, 1,635 trait–SNP associations were among the top quantitative trait locus candidates. Lastly, 664 candidate genes associated with 13 blood traits were identified. The most significant were ZNF772, MTX2, ESRRG, MEI4, IL11, FRMPD4, GABPA, NTF4, CRYBG3, ENPP5, COL16A1, and CD207. The results of our genome-wide association study provide a list of significant SNPs and candidate genes, which offer valuable information for further dissection of the molecular mechanisms that regulate the camel’s hematological traits to ultimately reveal their tolerance mechanisms.

Objective: Old World camels are a valuable genetic resource for many countries around the world due to their adaptation to the desert environment. At present, Old World camels have encountered the challenge of unprecedented loss of genetic resources. Through our research, we would reveal the population structure and genetic variation in Old World camel populations, which provides a theoretical basis for understanding the germplasm resources and origin and evolution of different Old World camel populations.Methods: In the present study, we assessed mtDNA control region sequences of 182 individuals from Old World camels to unravel genetic diversity, phylogeography, and demographic dynamics.Results: Thirty-two haplotypes confirmed by 54 polymorphic sites were identified in the 156 sequences, which included 129 domestic and 27 wild Bactrian camels. Meanwhile, 14 haplotypes were defined by 47 polymorphic sites from 26 sequences in the dromedaries. The wild Bactrian camel population showed the lowest haplotype and nucleotide diversity, while the dromedaries investigated had the highest. The phylogenetic analysis suggests that there are several shared haplotypes in different Bactrian camel populations, and that there has been genetic introgression between domestic Bactrian camels and dromedaries. In addition, positive values of Tajima’s D and Fu’s Fs test demonstrated a decrease in population size and/or balancing selection in the wild Bactrian camel population. In contrast, the negative values of Tajima’s D and Fu’s Fs test in East Asian Bactrian camel populations explained the demographic expansion and/or positive selection.Conclusion: In summary, we report novel information regarding the genetic diversity, population structure and demographic dynamics of Old World camels. The findings obtained from the present study reveal that abundant genetic diversity occurs in domestic Bactrian camel populations and dromedaries, while there are low levels of haplotype and nucleotide diversity in the wild Bactrian camel population.