Neonatal Calf Diarrhea

important questions to ask when investigating calf diarrhea on a farm

number of calves affected; ages of affected calves; how long have the calves been scouring for; any treatments provided; colostrum management on farm; cow vaccination pre-calving

what other problems might you see in calves with diarrhea?

dehydration, metabolic acidosis, electrolyte imbalance, hypovolemia, hypoglycemia, hypothermia

what are the most likely etiologies for calf diarrhea and why?

infectious — infectious agents often result in secondary inflammatory lesions in the small intestine

nutritional — poor colostrum intake or feeding can either cause diarrhea directly or predispose calves to infectious disease (poor immune system function increases risk of infection)

what are some infectious differentials for a calf with diarrhea?

Rotavirus, Salmonella, Cryptosporidium, Coronavirus, E. Coli

what are some nutritional differentials for a calf with diarrhea?

overfeeding, incorrect milk powder concentration, irregular feeding, failure of passive transfer

when is a calf scours panel useful?

to identify the specific infectious etiological agent(s) causing neonatal diarrhea in order to guide targeted treatment, management, and control measures in the herd

when is serum total protein useful in cases of calf diarrhea?

to evaluate passive transfer status

**should not be taken from dehydrated calves (due to dehydration-related increases in serum proteins)

why is assessment of GGT useful?

to assess passive transfer of immunity by indicated colostrum uptake in the neonatal calf

if only one out of six calves had a low GGT, what might this indicate?

colostrum transfer was generally adequate across the group; the single low result suggests that one calf likely had failure of passive transfer, potentially due to inadequate intake, poor colostrum quality or delayed ingestion

why is blood-gas analysis useful in calves with diarrhea?

to assess acid-base status and identify metabolic acidosis, as well as associated electrolyte and ventilation abnormalities

what health and safety considerations need to be discussed when managing scouring calves?

zoonotic risk! cryptosporidium, E.coli and salmonella are all zoonotic pathogens;

what treatments are indicated in calves with diarrhea?

oral electrolytes, NSAIDs, IV fluids + dextrose, isolation of affected calves, vitamin B12 (supports energy metabolism), bicarbonate supplementation (IV or oral); probiotics

what are some management factors that increase the risk of neonatal diarrhea on farms?

• overcrowd in pens/shed → reduced immune function and greater susceptibility to infection

• failure to isolate affected calves promptly → increases feco-oral spread via shared environment

• inadequate dam vaccination for rota/corona/crypto → reduced passive immunity via colostrum

• poor wet-weather paddock management

• poor colostrum management

if calves are 12-16 weeks, what differentials would be more likely in cases of scouring calves?

parasites (GINs such as Osteragia), coccidiosis (Eimeria spp), yersinosis, salmonellosis

how is coccidiosis prevented in calves?

Coccidiostats (such as decoquinate, monesin, or lasolocid) included in calf milk replacer and solid feeds

usually fed continuously until weaning

what clinical sign is highly suggestive of Yersiniosis in older calves?

marked hemorrhagic gastroenteritis; animals may be found dead or comatose with blood-stained feces

how is Yersiniosis treated in calves?

parenteral or systemic antimicrobials (like oxytetracycline) and supportive treatment such as analgesia, fluid therapy, and supplemental feed/water

what is clinical disease of Salmonellosis usually associated with?

“stress” factors eg transportation, starvation, changes in feed, overcrowding, pregnancy, parturition, exertion, anesthesia, surgery

young animals are more likely to develop septicemia in addition to enteritis

ZOONOTIC!!

how is salmonellosis treated?

antimicrobials effective against Gram negative enteric bacteria (eg oxytetracycline, TMPS and potentially use of red light antimicrobials ONLY if justified), fluid therapy, NSAIDs, supportive care