Experimental iron-inactivated Pasteurella multocida A: 1 vaccine adjuvanted with bacterial DNA is safe and protects chickens from fowl cholera.

Fowl cholera is a serious problem in large and small scale poultry production. The present study describes the development and testing of an inactivated whole-cell, low-cost, safe, and effective vaccine for fowl cholera based on a previous work (Vaccine 23:5590-5598). Pasteurella multocida A: 1 grown in the presence of low FeCl(3) concentrations, inactivated with higher concentrations of FeCl(3), and adjuvanted with bacterial DNA from P. multocida B: 2 containing immunostimulatory CpG motifs protect chickens with a lethal P. multocida A: 1 challenge. Chickens were immunized with two whole-cell inactivated vaccine doses at 4 weeks apart and challenged 4 weeks after booster immunization. Experimental vaccines were pure, easy injectable, and caused very little distress in chickens due to their aqueous consistency. Vaccines and bacterial DNA (bDNA) posed no safety problems when chickens were injected subcutaneously (s.c.) with a single, double, and overdose of these preparations. Immunized chickens produced systemic IgY antibodies (Ab) responses and vaccine adjuvanted with bDNA protected 100% chickens from lethal intrapertoneal (i.p.) P. multocida A: 1 challenge. This work suggests that use of bDNA as an adjuvant can improve the cost-effectiveness of inactivated veterinary vaccines for their use in developing countries. Our future studies will focus on safety and potency evaluation of experimental and current vaccines using bDNA as an adjuvant.

Evaluation of mammary gland immunity and therapeutic potential of Tinospora cordifolia against bovine subclinical mastitis.

Enhancement of the diseased mammary gland immunity and therapeutic potential of hydro-methanolic extract of Tinospora cordifolia (T. cordifolia; stem) in bovine subclinical mastitis was investigated. Somatic cell count (SCC), total bacterial count (TBC), phagocytic activity, and leukocyte lysosomal enzymes like myeloperoxidase and acid phosphatase activity and Interleukin-8 (IL-8) level were evaluated after intramammary infusion of hydro-methanolic extract (stem) of T.cordifolia in diseased cows. The qualitative analysis of the extract revealed the presence of polysaccharide, phenol, alkaloid, and protein. Intramammary infusion of hydro-methanolic extract of T. cordifolia treatment initially enhanced the SCC; thereafter, significant reduction in cell count (P < 0.05) was observed on day 15 of the treatment period, however, reduction in TBC was observed from day 3 onwards. The phagocytic activity of milk polymorphonuclear cells enhanced in the diseased cows treated with the T. cordifolia extract. Similarly, the lysosomal enzyme content of the milk polymorphonuclear cells enhanced significantly (P < 0.05) in diseased cows treated with T. cordifolia. The IL-8 level in milk serum also increased significantly (P < 0.05) in diseased cows treated with the herb extract. The results suggest that the hydro-methanolic extract of T.cordifolia (stem) possesses antibacterial and immunomodulatory properties. In the present study, the biological activity of the Tinospora cordifolia extract at standardized dose against bovine subclinical mastitis is reported for the first time. Development of alternative therapy with medicinal plants is an option for livestock farmers who are not allowed to use the conventional allopathic drugs under certain farming system or cannot afford to use allopathic drugs.

Immunotherapeutic potential of Ocimum sanctum (L) in bovine subclinical mastitis.

Immunotherapeutic potential of aqueous extract of Ocimum sanctum (O. sanctum) leaf in bovine sub-clinical mastitis (SCM) was investigated. Somatic cell count (SCC), total bacterial count (TBC), milk differential leukocyte count (DLC), phagocytic activity and Phagocytic index and leukocyte lysosomal enzymes like myeloperoxidase and acid phosphatase content were evaluated after intramammary infusion of aqueous leaf extract of O. sanctum. The results revealed that the aqueous extract of O. sanctum treatment reduced the TBC and increased neutrophil and lymphocyte counts with enhanced phagocytic activity and phagocytic index. Similarly, the lysosomal enzymes contents of the milk polymorphonuclear cells (PMNs) were also enhanced significantly in animals treated with the extract. The results suggest that the crude aqueous extract of O. sanctum (leaf) possesses some biologically active principles that are antibacterial and immunomodulatory in nature. As such, the present wok substantiates the therapeutic use of medicinal herb and also emphasizes on the potential of the commonly available non-toxic substances to enhance the mammary immunity.