L2: Control and Dx of Common Infectious Causes of Abortion in Cattle (Risco)

Question 1

infectious causes –> repro performance

Answer 1

fertilization failure

preg. loss

Question 2

repro efficiency of a dairy herd graph

Answer 2

slide 4
(parturition –> VWP –> breeding period –> parturition)
-milk yield peaks after parturition but before end of VWP/breeding period

Question 3

when does calf embryo become fetus?

Answer 3

43d

Question 4

majority of pregnancy loss occurs when?

Answer 4

by day 17

Question 5

early embryonic death days:

Answer 5

5-17

Question 6

late embryonic death days:

Answer 6

17-42

Question 7

fetal loss days:

Answer 7

43-term

Question 8

Bovine Herpesvirus Type 1 causes what dz process

Answer 8

Infectious Bovine Rhinotracheatis (IBR or Red Nose)

Question 9

total percent preg. loss from fertilization to term

Answer 9

60%

Question 10

what percent of eggs successfully fertilized?

Answer 10

76%

Question 11

what percent of inseminated cows will have viable embryos at day 6?

Answer 11

50%

Question 12

what percent of inseminated cows will carry to term?

Answer 12

28%

Question 13

Bovine Herpesvirus Type-1 trans.

Answer 13

• resp, ocular and reproductive secretions from infected cattle
• remains in post infected animals via latent infections of the trigeminal ganglia

Question 14

CS of BHV-1

Answer 14

• severe resp. tract infection w/5-10% death loss
• abortions (only in non-immunized dams)
• genital lesions: Infectious Pustular Vulvovaginitis (IPV) and Infectious Pustular Balanoposthitis (IPB)

Question 15

Dx of BHV-1

Answer 15

1) serum neutralization test (paired samples):
- 1st sample neg, 2nd pos.
- 1st. pos., 2nd 4x inc. pos.
- low titers
2) virus isolation from placenta

Question 16

BHV-1 vaccination

Answer 16

• calves: 6mo.
• pre-breeding
• modified live (gives lifelong immunity, naive non-pregnant only) or killed (pregnant cows, must re-boost)

Question 17

effect of Infectious Bovine Rhinotracheitis on ovary

Answer 17

• 30-40% dec. CR for estrous cycle following exposure

- follicular necrosis and lytic infection of developing CL

Question 18

Bovine Viral Diarrhea causes what diseases?

Answer 18

Hepatitis B
Hog cholera
Border disease

Question 19

what type of virus causes BVD

Answer 19

single stranded RNA

Question 20

CS in diseases caused by BVD**

Answer 20

(can be acute or subclinial/persistently infected)
immunosuppression***
thrombocytopenia
gastrointestinal
reproduction
congenital (ocular, cerebellar hypoplasia)

Question 21

2 types of BVD infection of calves during 1sst trimester of gestation

Answer 21

cytopathic –> fetal death, mummification

non-cytopathic (persistently infected) –> viable, immunotolerant, survives to term

Question 22

infection with BVD during 1st trimester can result in:

Answer 22

Early embryo death
abortion
mummification PI calf

Question 23

infection with BVD during 2nd trimester can result in:

Answer 23

cerebellar hypoplasia
ocular defects
abortion

Question 24

infection with BVD during 3rd trimester can result in:

Answer 24

no effect (calf has Ab to BVD)

Question 25

Dx of BVD

Answer 25

- virus isolation from whole blood | - PCR amplification for Ag and Ab

Question 26

prevent/control BVD

Answer 26

- detect and eliminate PI animals - MLV vax for non-pregnant cows, calves - KV for preg. cows + boosters

Question 27

leptospirosis trans.

Answer 27

urine, products of abortion | -invades mm (incubates 4-10d, bacteremia 2-6wks, leptospiruria 2-6mo.)

Question 28

is leptospirosis zoonotic?

Answer 28

yes!

Question 29

2 types of Leptospira serovar hardjo

Answer 29

prajitno and bovis

Question 30

what type of hosts experience acute form of lepto?

Answer 30

INCIDENTAL hosts - high dose required for infection - short-term leptospiruria

Question 31

what type of hosts experience chronic form of lepto?

Answer 31

MAINTENANCE hosts - lifelong shedding in the urine - asymptomatic - high susceptibility - infected with host adapted serovar-endemic infection

Question 32

serovar bratislava maintenance host***

Answer 32

swine, horses

Question 33

canicola maintenance host***

Answer 33

dogs

Question 34

grippotyphosa maintenance host***

Answer 34

racoons skunks opossom

Question 35

hardgo bovis maintenance host***

Answer 35

cattle

Question 36

icterohaemorrhagiae maintenance host***

Answer 36

rats

Question 37

pomona type maintenance host***

Answer 37

swine, cattle, skunks, opossum | *causes acute infection in calves*

Question 38

CS of chronic maintenance serovars of lepto

Answer 38

infertility abortion agalactia mastitis

Question 39

CS of acute incidental serovars of lepto

Answer 39

``` hemoglobinuria fever hemolytic anemia jaundice nephrosis agalactia mastitis ```

Question 40

CS of acute infection in calves with lepto

Answer 40

``` (uncommon) hemoglobinuria fever anemia icterus dyspnea +/-meningitis ```

Question 41

which serovars of lepto cause abortion**

Answer 41

pomona hardgo** -usually occurs at 7-9mo.

Question 42

Indirect Dx of lepto

Answer 42

microagglutination - specific, but not sensitive for some serovars - results affected by vax status

Question 43

Direct Dx of lepto

Answer 43

culture PCR FAT urine collection with use of diuretic

Question 44

control of lepto

Answer 44

- vaccination (only gives immunity for 6 mo.) - env. management - wildlife management (for Pomona and grippo) - tx with OTC

Question 45

chars. of campylobacteriosis (Vibriosis)

Answer 45

- caused by Campylobactor fetus sp. venerealis - venereal dz of cattle char. by infertility and occasional abortion - causes low preg. rates

Question 46

dx of campylobacteriosis (Vibriosis)

Answer 46

- herd history | - abx in cervical mucus

Question 47

control of campylobacteriosis (Vibriosis)

Answer 47

- vax (last 4mo.) | - changes in breeding management: use young bulls, check during breeding soundness exam, change to AI

Question 48

chars. of Trichomonosis

Answer 48

- caused by tritrichomonas foetus (protozoan) | - veneral dz of cattle char. by infertility, occasional early abortion or pyometra

Question 49

Dx of Trichomonosis

Answer 49

exam of prepuce in bulls, pyometra fluid

Question 50

Control of Trichomonosis

Answer 50

- changes in breeding man.: use young bulls - vax in cows - check during BSE - change to AI

Question 51

chars. of Neosporosis**

Answer 51

- major cause of abortion in dairy cattle*** - neospora caninum - dogs may be reservoir - vertical trans. possible - causes lesions in brain of fetus

Question 52

Dz occurs when:

Answer 52

herd immunity drops below lvl of disease pressure

Question 53

2ary or Anamnestic response

Answer 53

response seen after a booster vaccination - stronger, longer lived - primarily IgG - more memory made

Question 54

minimum vaccination program should include:

Answer 54

vax to 4 major viral diseases: BVD 1 and 2 herpesvirus respiratory syncytial Also: leptospira, clostridia, core endotoxin, vibriosis if bulls used, etc.