This study aimed to evaluate the influences of electrical stimulation (ES), age at slaughter, and breed type on muscle pH, the decline in carcass temperature, and meat quality attributes of Sudanese indigenous Baggara cattle. Eighty Baggara bulls, representative of Nyalawi (n = 40) and Mesairi (n = 40) breed types, were selected at their typical marketing age of about 4.5 years. Electrical stimulation was applied for 30 seconds at 20 minutes post mortem to 20 randomly selected carcasses from each breed type and compared with 20 carcasses from each type that were not electrically stimulated (NES). Samples of the Longissimus dorsi muscle were collected for meat analyses. Breed type showed no significant influence on meat quality characteristics, while ES and age at slaughter did. Electrical stimulation accelerated the carcass pH decline significantly up to 24 hours post mortem. Meat from electrically stimulated carcasses and younger animals resulted in higher L* values, lower a* values, higher hue values, and better tenderness. Older Mesairi animals had darker meat than their younger counterparts. Electrical stimulation reduced water-holding capacity (WHC), although it had no influence on cooking loss (CL). Meat from older cattle showed better WHC compared with meat from younger animals. The ES treatment decreased the variations in meat tenderness between the younger and older bulls. It is concluded that the use of ES and younger bulls produced more tender meat with better colour. Therefore, these practices should be adopted in Sudan to ensure better beef quality management.

The present study was conducted on 112 Sudanese Baggara bulls (Nyalawi and Mesairi strains) from two separate locations in Darfur and Kordofan, Sudan, raised under dryland farming conditions. A single nucleotide polymorphism (C/T) Arg25Cys in exon 2 of the bovine leptin gene (NC_032653.1) was studied and the association of leptin genotypes with meat quality attributes was evaluated for these two Sudanese Baggara cattle strains which comprise the mainstay of Sudan export and local beef trade. The accuracy of genotyping was checked through PCR-RFLP technique followed by DNA sequencing and analyzed using BioEdit, MEGA6 and project Hope softwares. The genotype frequencies for CC, CT and TT genotypes in Nyalawi strain were 37.5, 39.3 and 23.2%, respectively, whereas the respective genotypic frequencies for Mesairi strain were 46.4, 28.6 and 25%. Significant differences (P<0.05) were found in hot carcass weight, dressing percentage, Myofibril fragmentation index (MFI), water holding capacity (WHC), cooking loss, moisture and fat between the two Baggara cattle strains. Association between the C>T SNP at the leptin gene and carcass weight, dressing and fat percentages was significant (P<0.05). It was concluded that Leptin gene polymorphisms contributed to the observed meat quality differences among these Sudanese cattle strains. This will allow for the use of molecular information in future selection of beef cattle in Sudan. The possible value of the leptin gene and its polymorphisms have been elucidated for the first time in Baggara cattle.

The study involved 127 bulls of two geographically separate strains of Sudanese Baggara zebu cattle (Nyalawi and Mesairi). The target was to investigate two polymorphisms in growth hormone gene (M57764) and insulin like growth factor1 gene (000162.1). PCR-RFLP was used to genotype DNA samples and DNA sequencing was used to check the accuracy of genotyping results using selected samples. Available sequences were analyzed using BioEdit and MEGA6 softwares. Some population genetic measures in the two strains of Baggara zebu cattle were investigated. PCR-RFLP revealed that the two Baggara cattle strains have high genetic similarity at position 2141C>G of the GH1 gene (monomorphic showing the ancestral allele C/C). There were no differences between the two strains at position-472C>T of the IGF-1 gene promoter. The mutant homozygote (TT) was detected in the Mesairi strain only with a frequency of 0.016. The heterozygote (CT) genotype existed in the two strains with low allele frequencies (0. 068 and 0.079 for Nyalawi and Mesairi respectively). Moreover, three mutations were identified in exon5 of the GH1 sequence including two silent mutations at positions 2230 (C>T) and 2291(A>C) and a third transition mutation at position 2258 (C/T) detected in the sequences of the two strains. In conclusion, the two strains were found to be genetically similar at target positions. The detected mutation at exon 5 of GH1 (2258 (C/T) should be validated.