Chitin digestibility is dependent on feeding behaviors, which determine acidic chitinase mRNA levels in mammalian and poultry stomachs.

Chitin, a polymer of N-acetyl-D-glucosamine (GlcNAc), serves as a key structural component of chitin-containing organisms including crustaceans, insects and fungi. More recently, we reported that the acidic chitinase (Chia) is highly expressed in mouse, chicken and pork belly network and that it can digest chitin in their gastrointestinal tract (GIT). 

In this study, we focus on major livestock and domestic animals General Clia Kits and showed that the mRNA levels of Chia in their stomach tissue is regulated by feeding behavior. Chia mRNA levels were significantly lower in cows (herbivores) and dogs (carnivores) of the stomach compared with rats, pigs and chicken (omnivores). Consistent with the level of mRNA, protein Chia is very low in the stomach of a cow. In addition, chitinolytic activity of E. 

coli-expressed enzyme Chia cows and dogs are pretty but significantly lower than those of the enzyme Chia omnivores. cows and dogs Chia recombinant enzyme can degrade chitin substrate under conditions of artificial GIT. Furthermore, the genome of some herbivorous animals such as rabbits and guinea pigs do not contain functional genes Chia. These results showed that the eating behavior affects the level of expression of Chia and chitinolytic enzyme activity, and determine the digestibility of chitin in certain animals.

bovine mastitis caused by Staphylococcus aureus is a serious problem in the production of milk and effective immunoprophylaxis is a goal that has not been fulfilled so far. The purpose of this study was to assess the humoral immune response of calves against two recombinant S. aureus antigens: Clumping factor A Human Clia Kits (ClfA) and Fibronectin Binding Protein A (FnBPA), formulated with a novel adjuvant based on cationic liposomes (Lip) and CpG oligodeoxynucleotides (CpG -ODN). Six groups of 6-8 month old veal calves received three weekly doses of two antigens, formulated with Al (OH) 3, liposomes, CpG-ODN or Lip + CpG-ODN. 

Animals also received a fourth dose after one year (410 days) and a booster before calving. Administration of Al (OH) 3 + FnBPA / ClfA and Lip + FnBPA / ClfA + CpG-ODN induced the highest IgG certain level, after the first 3 doses and trigger a rapid increase of antibodies after the fourth dose. 

All formulations stimulates the production of IgG1 particular, after the third and fourth doses. IgG2 specific for the second protein is stimulated only after the fourth dose with Lip + FnBPA / ClfA + CpG-ODN. Pre-calving immunization with Lip + FnBPA / ClfA + CpG-ODN cause the highest IgG levels during the childbirth and for the production of IgG2 subclass. the formulation is also capable of inducing high antibody levels in mi

lk, 30 and 45 days after calving pre-amplifier. 

The combination of liposomes and CpG-ODN as an adjuvant for a subunit vaccine, together with the immunization schedule described, triggering a strong humoral immune response with production of specific IgG2. The formulation demonstrated to induce immune memory which allows a single application of the pre-calving amplifier to maintain the high antibody levels during periods of increased susceptibility to intramammary infection.