Multidrug resistance and prevalence of microorganisms isolated from umbilical infections of suckling lambs diagnosed by mass spectrometry

Abstract

The consumption of sheep products and derivatives has increased all over the world, particularly consumers who are adept at the taste of sheep meat or intolerant of bovine milk. The first months after birth are considered critical in the life of the sucking lamb, due to the high occurrence of mortality secondary to umbilical infections, commonly related to inadequate consumption of colostrum, deficiencies in postpartum umbilical antisepsis, and maintenance of newborn animals in environments with dirt, feces, and moisture. Umbilical infections origin can progress to serious complications, e.g., pneumonia, (poly)arthritis, organ abscesses, encephalitis, and septicemia. Escherichia coli, Trueperella pyogenes, streptococci, staphylococci, Pseudomonas sp., and Proteus sp. are the most frequently microorganisms identified in in lambs with umbilical infections. The most common clinical signs of umbilical infection include edema, pain on palpation, and hyperemia of the umbilicus, with or without purulent secretion. In bovine calf, the severity of umbilical infections is classified in different scores: 1 (mild), 2 (moderate), and 3 (severe). Routine diagnosis is based on anamnesis, physical examination of the umbilical region, microbiological culture (phenotypic tests), and in vitro antimicrobial sensitivity pattern of the isolates. Treatment consists on supportive therapy and broad-spectrum antimicrobials, preferably supported by in vitro sensitivity tests. The prognosis is poor, especially in cases of systemic complications secondary to umbilical infections. Despite the damage caused in sheep farming, a limited number of studies have investigated the causal agents of infectious umbilical infections in lambs; restricted to report of cases and diagnosis in species level of agents based on conventional phenotypic tests. In this scenario, the present study will investigate the microbial etiology of umbilical infections in suckling lambs diagnosed based on mass spectrometry, classify the scores of umbilical lesions (and possible association with specific agents), and determine multidrug resistance of isolates.