Infectious Causes Of Reproduction Failure (Pg4)

Front 1

Group 1 Infectious Agents

1) What is the type?

2) What are the most common agents and/or disorders? (6)

Back 1

1) Ubiquitous micro-organisms that occur as common commensals.

2) Arcanobacterium pyogenes, E. coli, Erysipelothrix rhusiopathiae, Streptococcus spp, Salmonella spp, Staphylococcus aureus.

Front 2

Group 2 Infectious Agents

1) What is the type?

2) What are the most common agents and/or disorders? (6)

Back 2

1) Contagious micro-organisms which are present in a high proportion of pig herds.
2) PRRS, porcine parvovirus, Leptospira bratislava, Swine influenza, Porcine circovirus 2, Enteroviruses.

Front 3

Group 3 Infectious Agents

1) What is the type?

2) What are the most common agents and/or disorders? (6)

Back 3

1) Infections associated with severe reproductive disease which are uncommon or absent from the UK.

2) Aujjeszky's disease, Swine fever, Brucellosis, SVD, Foot and Mouth Disease (FMD), TGE.

Front 4

How many infection enter the uterus? (2)

Back 4

1) Ascending through the cervix post-service or at farrowing (problems most common in early gestation-leading to endometritis and vaginal discharge).

2) The hematogenous route (any stage of pregnancy-localization in the endometrium or enter the lumen, leading to placental damage and fetal death).

Front 5

How are problems investigated?

Back 5

Clinical history and signs, detection of the agent (in the right location) during the acute stage or paired serology.

Front 6

Reproductive failure associated with vaginal discharge in the sow after service

1) What is the aetiology?
2) What is the epidemiology?

3) How can this be treated?

4) What are control measures?

5) When is this seen?

6) In what group is a higher prevalence seen?

Back 6

1) Mixed population of ubiquitous organisms (e.g. A. pyogenes, E. coli, Streptococci, Pseudomonas spp). Eubacterium suis infection common in cystitis or pyelonephritis.

2) Environmental factors important (can be introduced through infected genitalia).

3) Sows: Long-acting broad spectrum antibiotic by injection or instillation via AI catheter.

*Note that if discharge within first week after service-usually seminal debris.

Boars: long acting broad-spectrum antibiotic by injection and infuse prepuce with intramammary tubes daily for 5d.

*If widespread issue, then can use in-feed antibiotic medication given to sows post weaning up to 28d post service.

4) Do not re-serve sows while discharging. Once recovered, use AI for next service. Cull sows at parity 7. Adopt stringent hygiene for boar pens, service pens, and sow stalls/accommodation (esp. used in the first 21d post service).

5) 10-20d post service. May persist for weeks/months if untreated or resolve spontaneously after 1-2w.

6) High parity sows (more than 4).

Front 7

Coliform mastitis

1) How do organisms reach teats?

2) Is this associated with immunity?

3) What are the clinical signs?

4) How can this be treated?

5) How can it be prevented?

Back 7

1) Through inadequate hygiene or via piglet's oral flora.

2) NO, not associated with protective immunity.

3) Initial signs on 1-2d post farrowing (but may occur during parturition), temperature (up to 42C), listless, weak, loss of interest in piglets, prefer sternal recumbency, may become weak and comatose (rare), reduced feed and water intake. Signs last 2-3d. Skin over mammary area reddened. Possible SQ edema.

*Piglets gaunt and hungry looking, continually trying to feed, restless.

4) Broad-spectrum antibiotic, NSAIDs, oxytocin. Care for piglets, cross fostering, feed with milk substitute, prevent chilling.

5) Good hygiene.

Front 8

What is meant by:
1) Direct effects of virus

2) Indirect effects of virus

Back 8

1) When virus causes a systemic reaction which results in a cytokine burst that can cause systemic effects (e.g. fever, anorexia, abortions).

2) When a virus replicates in the reproductive tract or fetus.

Front 9

What are common viral infections of the reproductive system in pigs? (4)

Back 9

1) Porcine reproductive and respiratory syndrome (PRRS, Blue Ear)

2) Swine Influenza

3) Porcine Parvovirus

4) Porcine Circovirus type 2

Front 10

Porcine Reproductive and Respiratory Syndrome (PRRS, Blue Ear)

1) What is the aetiology?

2) What are the clinical signs?

3) What are epidemiological features?

4) Describe the pathogenesis

5) How can it be diagnosed?

6) What are the ddx?

7) What are prophylactic management strategies?

Back 10

1) RNA virus. Different strains in USA, Asia, and Europe. Acute phase of dz lasts approximately 4-16w. Consistent features: reproductive losses in pregnant stock, increased pre-weaning mortality, and influenza like illness affecting all ages of pigs.

2) Non-specific illness in sows (anorexia and dullness), then 1-2w later reproductive losses followed by unthriftiness, respiratory illness, and mortality in piglets and all ages of growing stock. Neonatal piglets: respiratory dz, scour, unthriftiness, high mortality. Semen quality may be impaired. Blue ears, snout, and vulva occasionally seen (1-5%). Reproductive problems include infertility, premature farrowing, stillbirths, and weakly piglets born.

3) No evidence of human infection. Found worldwide. No non-porcine hosts identified. Pig-to-pig transmission occurs readily. Introduction through carrier animals, airborne spread, semen, and fomites.

4) Incubation period 1-7d. Farrowing abnormalities and neonatal deaths follow after 14-28d. Fetal infection can occur following maternal challenge in late pregnancy resulting inpre and post natal dz, abortions may result from purely maternal illness. Protective immunity may develop.

5) Clinical features, serology, virus isolation. PCR test from blood, semen, throat swabs.

6) Swine influenza, Aujeszky's dz.

7) If PRRS free: buy replacements and AI semen from sero-negative herds, ensure thorough biosecurity. Vaccines available.

Front 11

Swine Influenza

1) What is the aetiology?

2) What are the clinical signs?

3) Describe the pathogenesis

4) What are epidemiological features?

5) How can it be diagnosed?

6) What are the ddx?

7) What are the prophylactic management strategies?

Back 11

1) 4 strains of influenza A virus in UK. Avian-like strain is recurring problem. Acute phase dz 4-16w. Consistent features: influenza-like illness affecting all ages of pigs, reproductive losses in pregnant stock, and increased pre-weaning mortality.

2) Very similar to PRRS except respiratory signs are more widespread and severe.

3) Virus enters respiratory tract, multiplies rapidly in bronchial epi, virus disappears by 9-10d post infection. Animals can become viraemic. Transplacental infection occurs.

4) Infection can persist for months. Maternal immunity demonstrable for up to4m and can interfere with development of active immunity. ZOONOSIS.

5) Clinical features, serology, virus isolation.

6) PRRS, Aujeszky's dz.

7) Do not allow staff or any visitors who are suffering from influenza to have contact with pigs. If influenza free: buy replacements from sero-negative herds. Enforce herd biosecurity. Only one vax available in UK.

Front 12

Porcine Parvovirus

1) What is the aetiology?

2) What are the clinical signs?

3) Describe the pathogenesis

4) How can it be diagnosed?

5) What are the ddx?

6) How can it be controlled?

Back 12

1) Occurs worldwide. V high prevalence in UK herds. Associated with SMEDI syndrome and enteroviruses.

2) All reproduction associated: Stillbirths, mummification, embryonic death, infertility, increased regular and irregular returns to oestrus, small litters.

Signs depend on stage of pregnancy:

*Less than 35d: failure to implant, re-absorption, return to oestrus.

*35-70d gestation: mummification, piglets are infected progressively, resulting in small to large mummies.

*After 700d: stillbirths, live but weakly piglets.

3) Infection by oro-nasal or venereal routes, viraemia, transplacental spread 10-14d post-infection. Spreads into boar reproductive organs and semen (7-21d post infection). Virus adheres to eggs, embryos, and fetuses until they reach immunocompetence at 70d gestation. Colostral-derived immunity lasts 4-6m.

4) Clinical features, paired maternal serology. Fetuses: virus detection. Serology in large, fresh fetuses and stillborns.

5) PRRS, Enteroviruses, Swine influenza, Leptospirosis, Aujeszky's dz, Brucella.

6) Vaccinate susceptible stock. Annual vax rec.

Front 13

Porcine Parvovirus type 2

1) What is this primarily associated with?

2) What groups are at risk?

Back 13

1) Posteweaning multisystemic wasting syndrome (PMWS). Most herds endemically infected.

2) Naive herds or infection of naive gilts. Leads to reproductive problems including transient infertility, fetal re-absorption, and increased regular and irregular returns to oestrus.

Front 14

What is the most common bacterial infection affecting reproduction in pigs?

Back 14

Porcine Leptospirosis

Front 15

Porcine Leptospirosis

1) What is the aetiology?

2) What are the clinical signs?

3) Describe the pathogenesis

4) How can it be diagnosed?

5) What are the ddx?

6) How can it be controlled?

Back 15

1) Leptospira. Occurs worldwide, with varying serotypes and serovars. L. bratislava is most imp in UK. More common in outdoor units.
2) Mainly reproductive in the UK. Abortion, stillbirths, weak piglets of reduced viability. Abortion in last trimester common. Infertility, increased returns to service.
3) Infection by oro-nasal, venereal routes. Bacteremia, localized in renal tubules, shed in urine. Transplacental infection can occur, localizes in uterus, fetal invasion, abortion 10d-4w post-infection. Infection can persist in urinary and genital tracts of boars and sows.
4) Clinical signs, paired maternal serology. Fetus: antigen detection (FAT), serology.
5) PRRS, Parvovirus, Erysipelas, Swine influenza, Aujeszky's dz, Salmonella, Brucella.
6) In-feed medication of sows (Chlortetracycline 3kg/tonne) for 1 month in spring and 1 month in autumn. Prevent contact with free-living vectors. No vax available in UK.

Front 16

What are common commensal bacteria? (4)

Back 16

A. pyogenes, E. Coli, Streptococci spp, Salmonella spp