Understanding the genetic structure of domestic species provides a window into the process of domestication. This study attempts to offer an insight into the prevailing genetic status of Tunisian indigenous rabbit breeds using molecular markers. Thirty-six microsatellite loci were used to provide a comprehensive insight into the genetic status and relationship among 12 Tunisian indigenous rabbit populations. A total of 264 rabbits from villages of the Tozeur and Kebili regions were studied. Standard statistics parameters of genetic variability within and between populations were calculated. The observed heterozygosity, unbiased expected heterozygosity and the effective number of alleles were used to assess the genetic variation of each indigenous breed. Results show a high genetic diversity and observed heterozygosity ranged between 0.3 and 0.5, which implies that there is an abundant genetic variation stored in Tunisian indigenous rabbit breeds. Significant population differentiation was observed (F ST =0.11), which means that most of the genetic variation resides within breeds. The percentage of individuals correctly classified to their population was 85%. Breeds with more than one breeder origin were divided into subgroups, due to differences in gene frequencies between breeders, which in some cases creates a genetic differentiation even higher than that observed between distinct breeds. The current study is the first detailed analysis of the genetic diversity of Tunisian indigenous rabbit populations. The data generated here provides valuable information about the genetic structure of the 12 rabbit populations and this can be used to designate priorities for their conservation.

Heat stress is one of the most stressful events in livestock life, negatively impacting animal health, productivity, and product quality. Moreover, the negative impact of heat stress on animal product quality has recently attracted increasing public awareness and concern. The purpose of this review is to discuss the effects of heat stress on the quality and the physicochemical component of meat in ruminants, pigs, rabbits, and poultry. Based on PRISMA guidelines, research articles were identified, screened, and summarized based on inclusion criteria for heat stress on meat safety and quality. Data were obtained from the Web of Science. Many studies reported the increased incidences of heat stress on animal welfare and meat quality. Although heat stress impacts can be variable depending on the severity and duration, the exposure of animals to heat stress (HS) can affect meat quality. Recent studies have shown that HS not only causes physiological and metabolic disturbances in living animals but also alters the rate and extent of glycolysis in postmortem muscles, resulting in changes in pH values that affect carcasses and meat. It has been shown to have a plausible effect on quality and antioxidant activity. Acute heat stress just before slaughter stimulates muscle glycogenolysis and can result in pale, tender, and exudative (PSE) meat characterized by low water-holding capacity (WHC). The enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) act by scavenging both intracellular and extracellular superoxide radicals and preventing the lipid peroxidation of the plasma membrane. Therefore, understanding and controlling environmental conditions is crucial to successful animal production and product safety. The objective of this review was to investigate the effects of HS on meat quality and antioxidant status.

Deoxyribonucleic acid (DNA) can be extracted from different tissue sources. The most common is blood, but in some situations it can be easier to take a biopsy. In some cases when it is difficult to capture animals, especially in wild populations, faeces and hairs can be considered as a source of DNA. This paper presents a pilot study conducted to compare the applicability of invasive and non-invasive sampling methods for extracting DNA for use in genetic studies of rabbits (Oryctolagus cuniculus). The study included 24 rabbits from the INRA 1001 strain. Blood, hair, ear biopsies and faeces were collected and used as DNA sources. Our aim was to verify the quantity of DNA obtained from different tissues using 2 or 3 types of extraction. DNA was obtained for all tissue types and all extraction methods. DNA extraction was shown to be optimal with the LGC (Laboratory of Cellular Genetics) blood extraction method. With regard to non-invasive methods, DNA extraction for hair using the LGC protocol and QIAamp ® DNA mini kit gave very low quantities of DNA that could not be used for PCR reactions. The Chelex extraction protocol gave good results for PCR but could not be quantified. DNA extracted from faeces is a viable source of DNA for determining individual genotypes. The use of such non-invasive samples as a source of genetic material is a recent and very promising technique, especially for the study of endangered species, but these techniques are still too unreliable and costly to altogether replace invasive techniques when the latter are possible.

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