Efficacy of Bdellovibrio bacteriovorus 109J for the treatment of dairy calves with experimentally induced infectious bovine keratoconjunctivitis

Abstract

OBJECTIVE To determine the efficacy of Bdellovibrio bacteriovorus 109J for the treatment of calves with experimentally induced infectious bovine keratoconjunctivitis (IBK). ANIMALS 12 healthy dairy calves. PROCEDURES For each calf, a grid keratotomy was performed on both eyes immediately before inoculation with Moraxella bovis hemolytic strain Epp63-300 (n = 11 calves) or nonhemolytic strain 12040577 (1 calf). For each calf inoculated with M bovis Epp63-300, the eyes were randomly assigned to receive an artificial tear solution with (treatment group) or without (control group) lyophilized B bacteriovorus 109J. Six doses of the assigned treatment (0.2 mL/eye, topically, q 48 h) were administered to each eye. On nontreatment days, eyes were assessed and corneal swab specimens and tear samples were collected for bacterial culture. Calves were euthanized 12 days after M bovis inoculation. The eyes were harvested for gross and histologic evaluation and bacterial culture. RESULTS The calf inoculated with M bovis 12040577 did not develop corneal ulcers. Of the 22 eyes inoculated with M bovis Epp63-300, 18 developed corneal ulcers consistent with IBK within 48 hours after inoculation; 4 of those eyes developed secondary corneal ulcers that were not consistent with IBK. Corneal ulcer size and severity and the time required for ulcer healing did not differ between the treatment and control groups. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that B bacteriovorus 109J was not effective for the treatment of IBK; however, the experimental model used produced lesions that did not completely mimic naturally occurring IBK.

Lyophilization of Bdellovibrio bacteriovorus 109J for Long‐Term Storage

“…Controlled freeze drying is an excellent method for preserving a wide variety of heatsensitive materials such as bacteria. Lyophilization of B. bacteriovorus grown on M. bovis has been previously described by the authors (Boileau et al, 2016).…”

Predatory bacteria can protect SKH-1 mice from a lethal plague challenge

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The impact of predatory bacteria on experimental periodontitis

“…In vivo studies to date have evaluated the effects of BALOs in the treatment of infections in chickens, rats, cattle, zebrafish, and white shrimp . The effects of BALOs were also evaluated in the intestinal morphology and microbiota of healthy rats .…”