Mesenchymal stem cells (MSCs) are the most promising seed cells for cell therapy. Comparing the biological and transcriptome gene characteristics of MSCs from different sources provides an important basis for the screening of clinically used cells. The main purpose of this experiment was to establish methods for the isolation and culture of MSCs from five different canine sources, including adipose tissue, bone marrow, umbilical cord, amniotic membrane, and placenta, and compare biological and transcriptome characteristics of MSCs, in order to provide a basis for the clinical application of canine MSCs. MSCs were isolated from Chinese pastoral dogs, and the following experiments were performed: (1) the third, sixth, and ninth generations of cells were counted, respectively, and a growth curve was plotted to calculate the MSC population doubling time; (2) the expression of CD34 and CD44 surface markers was studied by immunofluorescence; (3) the third generation of cells were used for osteogenetic and adipogenic differentiation experiments; and (4) MSC transcriptome profiles were performed using RNA sequencing. All of the five types of MSCs showed fibroblast-like adherent growth. The cell surface expressed CD44 instead of CD34; the third-generation MSCs had the highest proliferative activity. The average population doubling time of adipose mesenchymal stem cells (AD-MSCs), placenta mesenchymal stem cells (P-MSCs), bone marrow mesenchymal stem cells (BM-MSCs), umbilical cord mesenchymal stem cells (UC-MSCs), and amniotic mesenchymal stem cells (AM-MSCs) were 15.8 h, 21.2 h, 26.2 h, 35 h, and 41.9 h, respectively. All five types of MSCs could be induced to differentiate into adipocytes and osteoblasts in vitro, with lipid droplets appearing after 8 days and bone formation occurring 5 days after AD-MSC induction. However, the multilineage differentiation for the remaining of MSCs was longer compared to that of the AD-MSCs. The MSC transcriptome profiles showed that AD-MSC and BM-MSCs had the highest homology, while P-MSCs were significantly different compared to the other four types of MSCs. All the isolated MSCs had the main biological characteristics of MSCs. AD-MSCs had the shortest time for proliferation, adipogenesis, and osteogenic differentiation.

Yield and quality are fundamental features for any researchers during nucleic acid extraction. Here, we describe a simplified, semi-unified, effective, and toxic material free protocol for extracting DNA and RNA from different prokaryotic and eukaryotic sources exploiting the physical and chemical properties of nucleic acids. Furthermore, this protocol showed that DNA and RNA are under triple protection (i.e. EDTA, SDS and NaCl) during lysis step, and this environment is improper for RNase to have DNA liberated of RNA and even for DNase to degrade the DNA. Therefore, the complete removal of RNA under RNase influence is achieved when RNase is added after DNA extraction, which gives optimal quality with any protocols. Similarly, DNA contamination in an isolated RNA is degraded by DNase to obtain high-quality RNA. Our protocol is the protocol of choice in terms of simplicity, recovery time, environmental safety, amount, purity, PCR and RT-PCR applicability.

This study was conducted to investigate the causes of mortality in young rabbits. A total of 110 V-Line breed female rabbits aged 5 m were used in this study. Rabbit kits were examined daily in pre- and postweaning stages to detect clinical disorders that caused death. The postmortem examination was carried out on dead kits. Furthermore, rabbits were examined for the probable bacteriological and parasitological causes of death. Fecal samples were collected from each dead kit and examined by standard microbiological procedures for bacterial pathogens and macroscopically and microscopically for the presence of endo- and ectoparasites. Throughout two breeding seasons, 2238 newborns were obtained, of which 1736 died, accounting for a 77.57% mortality rate. During preweaning (1st month of age) and postweaning (up to 3 months of age), 1501 (67.10%) and 235 (31.90%) deaths were recorded, respectively. A postweaning fecal examination revealed that 198 out of 229 (86.50%) were diarrheic rabbits due to Eimeria infection. Cittotaenia spp. eggs were detected in 4.37% of fecal samples, and mites (Sarcoptis scabiei) were present in 6.55%. E. coli was detected in 100% of examined animals during pre- and postweaning periods; however, Salmonella spp. were 97.22% and 43.67, respectively. Managemental risk factors were the main causes in preweaning mortality, including insufficient milk supply (37.37%), cannibalism (26.38%), mange infestation of a rabbit doe (22.20%), mastitis (4.30%), lack of doe care (5.00%), bronchopneumonia (2.13%), and enteritis (1.80%). However, risk factors in postweaning mortality included sudden death with general septicemia (13.80%), enteritis (9.63%), bronchopneumonia (5.43%), mange infestation (2.04%), and malnutrition (0.81%). In conclusion, the etiology of preweaning mortality in kits was related mainly to the doe, especially managemental risk factors. However, a combination of multiple pathogenic agents (parasites and bacteria) and managemental factors was reported in the postweaning stage. Careful attention must be paid to avoid these causes.

Shiga toxin-producing Escherichia coli (STEC) isolates (N = 38) that were incriminated in human disease from 2006 to 2013 in South Africa were characterized by serotype, virulence-associated genes, antimicrobial resistance and pulsed-field gel electrophoresis (PFGE). The isolates belonged to 11 O:H serotypes. STEC O26:H11 (24%) was the most frequent serotype associated with human disease, followed by O111:H8 (16%), O157:H7 (13%) and O117:H7 (13%). The majority of isolates were positive for key virulence-associated genes including stx1 (84%), eaeA (61%), ehxA (68.4%) and espP (55%), but lacked stx2 (29%), katP (42%), etpD (16%), saa (16%) and subA (3%). stx2 positive isolates carried stx2c (26%) and/or stx2d (26%) subtypes. All pathogenicity island encoded virulence marker genes were detected in all (100%) isolates except nleA (47%), nleC (84%) and nleD (76%). Multidrug resistance was observed in 89% of isolates. PFGE revealed 34 profiles with eight distinct clusters that shared ≥80% intra-serotype similarity, regardless of the year of isolation. In conclusion, STEC isolates that were implicated in human disease between 2006 and 2013 in South Africa were mainly non-O157 strains which possessed virulence genes and markers commonly associated with STEC strains that have been incriminated in mild to severe human disease worldwide. Improved STEC monitoring and surveillance programs are needed in South Africa to control and prevent STEC disease in humans.