Invited Review: Antimicrobial Use and Antimicrobial Resistance in Pathogens Associated with Diarrhea and Pneumonia in Dairy Calves

Abstract

Antimicrobial use (AMU) is the major driver of antimicrobial resistance (AMR) among bacteria in dairy herds. There have been numerous studies on AMU and AMR in dairy cows; however, studies on AMU and AMR in dairy calves are limited. A comprehensive overview of the current state of knowledge of AMU and AMR among pathogens in dairy calves is important for the development of scientifically supported and applicable measures to curb antimicrobial use and the increasing risk of AMR. Therefore, we performed a systematic review of research on AMU and AMR in dairy calves. A total of 75 publications were included, of which 19 studies reported AMU data for dairy calves and 68 described AMR profiles of the four most prevalent bacteria that are associated with calf diarrhea and calf pneumonia. Large variation in AMU was found among herds across different regions. There seems to be a positive association between exposure to antimicrobials and occurrence of resistance. Most AMU was accounted for by treatment of diseases, while a small proportion of AMU was prophylactic. AMU was more common in treating calf diarrhea than in treating pneumonia, and the resistance rates in bacteria associated with diarrhea were higher than those in pathogens related to pneumonia. Organic farms used significantly fewer antimicrobials to treat calf disease; however, the antimicrobial resistance rates of bacteria associated with calf diarrhea and pneumonia on both types of farms were comparable. Feeding waste or pasteurized milk was associated with a higher risk of AMR in pathogens. Altogether, this review summarizes AMU and AMR data for dairy calves and suggests areas for future research, providing evidence for the design of antimicrobial use stewardship programs in dairy calf farming.

Causes of Mortality of Dairy Cattle Diagnosed by Complete Necropsy

“…Predominant respiratory pathogens causing death in animals from 2 months to 1 year old were P. multocida , M. haemolytica , and T. pyogenes . Pasteurella multocida and M. haemolytica have been cited as the most common causes of pneumonia including fatal cases in this age group [ 30 , 31 ], but T. pyogenes was diagnosed as the primary cause of death in the present study more frequently than some reports. However, a literature review found the latter to be an important respiratory pathogen in dairy cattle as well [ 32 ].…”

Sodium acetate/sodium butyrate alleviates lipopolysaccharide-induced diarrhea in mice via regulating the gut microbiota, inflammatory cytokines, antioxidant levels, and NLRP3/Caspase-1 signaling

“…Though various kinds of measures have been implemented so far to fight against diarrhea, there is still a long way to go ( Cho et al, 2013 ). A recent review found that higher antimicrobial resistance was associated with the drugs being used for the treatment of diarrhea ( Zhang H. et al, 2022 ; Zhang X. et al, 2022 ); therefore, establishing a method to positively regulate the gut microbiota to ameliorate diarrhea is of great importance and meaningful ( Coelho et al, 2022 ).…”

Antimicrobial Resistance Genes in Respiratory Bacteria from Weaned Dairy Heifers

“…Weaned dairy heifers represent a unique production group, compared to pre-weaned calves or adult cattle, in which to study BRD and AMR. This population has unique management conditions that may influence BRD and AMR; they have recently been weaned off milk feeding, which is stressful [ 4 , 5 ], and many have received prior treatment with AMD during the pre-weaned period for BRD or diarrhea [ 3 , 6 , 7 , 8 , 9 , 10 ], and have been moved to group housing where they may be comingled with calves from other farms, which represents stress and a risk for pathogen and AMR spread [ 3 , 11 ]. Antimicrobial resistance (AMR) in food animals is an animal health, welfare, and One Health concern [ 12 , 13 , 14 , 15 ].…”