2022.Iss1.RaisingCommericalDairyCalves

Question 1

Cryptosporidiosis

How is crypto spread?

Answer 1

primarily fecal-oral transmission

**good hygiene is imperative to prevent the spread

Question 2

Cryptosporidiosis

Which species of cryptosporidium are found in adult cattle & infect the abomasum?

Answer 2

C. andersoni

Question 3

Cryptosporidiosis

Which species of cryptosporidium are primarily identified in weaned calves?

Answer 3

C. bovis
C. ryanae

Question 4

Cryptosporidiosis

What are important factors involved in increasing or decreasing the risk of cryptosporidosis in dairy calves?

Answer 4

Question 5

Cryptosporidiosis

What is the main clinical presentation of calves infected with C. parvum?

Answer 5

-diarrhea
-depression
-dehydration
-dec feed intake
-abdominal pain
-potentially tenesmus

Question 6

Cryptosporidiosis

What are the treatment recommendations for cryptosporidium in calves?

Answer 6

-supportive (usu dz is self limiting):
- replacement of fluids: oral electrolyte or IV solutions
-anti-inflammatories

Question 7

Cryptosporidiosis

Are there any licensed treatments for cryptosporidiosis in calves in the US?

Answer 7

None

Question 8

Cryptosporidiosis

Which factors are associated with morbidity and mortality with crypto in calves?

Answer 8

**colostrum may not be specifically protect against Crypto
–serum IgG levels & passive transfer of immunity are directly assoc with morbidity & mortality

Question 9

Milk Replacer Ingredients: What & Why Not?

Why is clean, wholesome whole milk inadequate for food for a calf?

Answer 9

because it doesn’t have appropriate vitamin & trace mineral nutrition

Question 10

Milk Replacer Ingredients: What & Why Not?

What is the largest ingredient expense in a CMR ?

Answer 10

protein
**care should be taken to use proven, consistent & suitable sources

Question 11

Milk Replacer Ingredients: What & Why Not?

What is a practice with colostrum/milk that is shown to improve gut health and reduce diarrhea?

Answer 11

-extending the feeding of colostrum and transition milk is shown to improve gut healthy & reduce diarreha

Question 12

Acceptable young calf vaccination strategies– what, when and how?

calves are born deficient in which vitamin?

Answer 12

Vitamin A
*colostrum is rich in vit A & active metbaolic forms: retinol, retinal, retinoic acid, provitamin beta carotene

Question 13

Acceptable young calf vaccination strategies– what, when and how?

The live colostral cells results has what reported benefits?

Answer 13

-less respiratory disease
-higher vaccine responses

Question 14

Acceptable young calf vaccination strategies– what, when and how?

which colostrum management practices reduce the effect of live cells?

Answer 14

pasteurization
freezing

Question 15

BRD Considerations in Young Dairy Calves

Name the 4 mechanisms that primary viral infections can compromise the house resulting in bacterial pneumonia.

Answer 15

1. damage to upper respiratory tract mucosa & mucociliary clearance mechanisms
2. damage to tracheal epithelial cells resulting in bact attachment
3. depletion or damage to innate host defense mechanism in teh airways and lungs including macros & neuts req for phagocytosis of foreign invaders
4. suppression of the acquired immune sys including both cell- mediated & humoral responses

Question 16

BRD Considerations in Young Dairy Calves

Which virulence factor of Mannheimia hemolytica causes cytolysis of ruminant lymphocytes, macros, plts & neutrophils?

Answer 16

exotoxin– leukotoxin

Question 17

BRD Considerations in Young Dairy Calves

Histophilus somni can result in septicemia and spread to what other organs causing disease?

Answer 17

endometrium–> endometritis
joints–> polyarthritis
heart–> myocarditis
lungs–> pneumonia

Question 18

BRD Considerations in Young Dairy Calves

Infections with mycoplasma bovis (or M dispar) can present clinically as:

Answer 18

mastitis
tenosynovitis
pneumonia-arthritis syndrome

Question 19

BRD Considerations in Young Dairy Calves

What is a big mechanism for Mycoplasma bovis, that allows for its extensive genetic and antigenic variation?

Answer 19

variable surface proteins & surface lipoproteins

Question 20

BRD Considerations in Young Dairy Calves

Mycoplasma bovis impairs which immune cells?

Answer 20

Neutrophils & macrophages– impairs activity
lymphocytes– apoptosis

Question 21

what are risk factors associated with respiratory disease in commercial dairy calves?

Answer 21

Question 22

Bacterial causes of intestinal disease in dairy calves: acceptable control measures

what are the most common enteric pathogens in neonates?

Answer 22

Escherichia coli
Salmonella enterica
Clostridium perfringens
+/- campylobacterspp

Question 23

Bacterial causes of intestinal disease in dairy calves: acceptable control measures

ETEC is most commonly seen in which age of calves?

Answer 23

within the first 4 day so f life
**colibacilosis can occur in any age calf

Question 24

Bacterial causes of intestinal disease in dairy calves: acceptable control measures ETECT most commonly produce which antigens?

Answer 24

-fimbrial antigens **most commonly F5 (K99) -enterotoxins-- heat stable entertoxin STa

Question 25

Bacterial causes of intestinal disease in dairy calves: acceptable control measures Diarrhea caused by the enteric salmonellosis in cattle is caused by which spp?

Answer 25

Salmonella enterica serotype typhimurium or sretype Dublin

Question 26

Bacterial causes of intestinal disease in dairy calves: acceptable control measures Which spp of salmonella is considered host-adapted to cattle?

Answer 26

Samonella dublin

Question 27

Bacterial causes of intestinal disease in dairy calves: acceptable control measures salmonella preferentially affects which part of the GIT?

Answer 27

distal small intestine & proximal large bowel

Question 28

Bacterial causes of intestinal disease in dairy calves: acceptable control measures Which type of clostridium perfringens is the associated with acute hemorrhagic abomasitis in neonates that manifests as colic, abdominal distension, depression & death?

Answer 28

Type A, C. perf

Question 29

Bacterial causes of intestinal disease in dairy calves: acceptable control measures Why is C. perfringens type C, disease most commonly seen in neonates younger than 10 days?

Answer 29

C. perf type C produces alpha & beta toxin **beta toxin-- is susceptible to trypsin degradation

Question 30

Bacterial causes of intestinal disease in dairy calves: acceptable control measures What are the 4 treatment goals for diarrhea in calves

Answer 30

1. correction of dehydration & electrolyte abnormalities 2. Correction of acid- base abnormalities 3. Provision of nutrition 4. treatment of bacterial infection

Question 31

Bacterial causes of intestinal disease in dairy calves: acceptable control measures What should be included in an appropriate oral electrolyte solution for calves?

Answer 31

*90-130 mmol/L sodium *40-80 mEq/L Chloride *10-30 mmol/L potassium *osmolality 300-600 mOsm *alkalinizing agent: acetate, proprionate, bicarbonate or citrate (>50 mmol/L) *strong ion difference >60 (Na+K-Cl)

Question 32

Bacterial Causes of Intestinal disease in Dairy Calves: Acceptable Control Measures What type of IV fluids are recommended in diarrheic calves (b/c they are typically acidotic)?

Answer 32

0.9% saline Ringers +/- bicarbonate

Question 33

Bacterial Causes of Intestinal disease in Dairy Calves: Acceptable Control Measures If unable to calculate a bicarb deficit in a calf, what is a good estimate to use?

Answer 33

standing calf: 250 mmol HCO3 weak calf, unable to stand: 500 mmol HCO3 recumbent calves: 750 mmol HCO3

Question 34

Bacterial Causes of Intestinal disease in Dairy Calves: Acceptable Control Measures Describe isotonic bicarbonate and how to make it?

Answer 34

isotonic bicarb is 156 mmol/L ---dissolve 13 g baking sode in 1 L water

Question 35

Bacterial Causes of Intestinal disease in Dairy Calves: Acceptable Control Measures What antibiotics are beneficial in calf diarrhea?

Answer 35

1. Amoxicillin 11-15 mg/kg IM once daily-- dec mortality in S dublin calves 2. ampicillin trihydrate 22 mg/kg SQ or IM SID dec mortality in naturally occuring diarrhea 3. florfenicol 20 mg/kg IM q48h for 2 doses shown efficacy against salmonella 4. ceftiofur hydrochloride: 5 mg/kg IM for 5 days dec C/S & fecal shedding of salmonella

Question 36

Bacterial Causes of Intestinal disease in Dairy Calves: Acceptable Control Measures What is a key preventative measure for prevention of ETEC in calf diarrhea?

Answer 36

colostrum management **colostral abs bind bact fimbriae in intestinal lumen and prevent adherence to intestinal epithelial cells

Question 37

Bacterial Causes of Intestinal disease in Dairy Calves: Acceptable Control Measures Vaccination of the damn using what component is beneficial in prevention of ETEC calf diarrhea?

Answer 37

vaccines directed against F5 (K99) at 6 and 3 weeks prior to calving

Question 38

Bacterial Causes of Intestinal disease in Dairy Calves: Acceptable Control Measures When using vaccination as a preventative measure against salmonella calf diarrhea, is MLV vs bacterin better?

Answer 38

MLV demonstrate better efficacy

Question 39

Rumen transition from weaning to 400 pounds which substrate is superior to developing rumen pappillae?

Answer 39

grain is superior to forage **dietary structural carbs into preweaning diet limits rumen papillae growth & density

Question 40

Rumen transition from weaning to 400 pounds How long does it take for rumen flora to populate the rumen and begin to efficiently ferment structural carbs in hay?

Answer 40

some bacteria 2-4 weeks

Question 41

Rumen transition from weaning to 400 pounds Differentiate VFA that are produced from diet

Answer 41

butyrate & proprionate: grain acetate: hay

Question 42

Preparing male dairy calves for the veal & dairy beef industry At dairy herds of origin, what are key factors to improve veal & dairy calf health?

Answer 42

1. assuring adequate bwt before transport (>50 kgs, 110 lbs), 2. adequate transfer of passive immunity 3. specific immunity by vaccination 4. avoid or alleviate stressors

Question 43

Preparing male dairy calves for the veal & dairy beef industry of the cattle industries, which has the highest use of antimicrobials despite the use of laws & sector initiatives w/in european union?

Answer 43

veal sector

Question 44

Preparing male dairy calves for the veal & dairy beef industry What are 2 vaccination strategies used for calves in the veal industry?

Answer 44

1. vaccination of dams combined with successful colostral mangmt 2. vaccinating calves either intranasally or intramuscularly if sufficient time on farm of origin is available