Pro­tect­ing your pigs and prof­its con­tin­ues her guide to im­prov­ing herd pro­duc­tiv­ity, this time in­ves­ti­gat­ing the im­por­tance of good health care

Country Smallholding - - Liz Shankland Pigs -

Liz Shank­land

urine. It can live out­side the pig for sev­eral months, sur­viv­ing in fae­ces and in the soil and in con­tam­i­nated feed, bed­ding and wa­ter. Stress or vi­ral in­fec­tions can make a pig more sus­cep­ti­ble. If it is dis­cov­ered at the abat­toir, car­casses can be con­demned.

The ef­fects vary ac­cord­ing to the age of the pig and the stage of preg­nancy, but symp­toms can in­clude: Failed preg­nan­cies and abor­tion Small lit­ter sizes Large num­bers of still­born piglets Mum­mi­fied piglets In­fer­til­ity in boars Se­vere and re­cur­ring lame­ness — af­fect­ing mo­bil­ity and so abil­ity to mate Sud­den death — usu­ally due to acute sep­ti­caemia or heart fail­ure. In the acute form of the dis­ease, the or­gan­ism gets into the blood stream and causes sep­ti­caemia, re­sult­ing in fever, stiff­ness while walk­ing, or a re­luc­tance to get up. In se­vere cases, the dis­ease spreads so fast that a pig which pre­vi­ously showed no signs of ill health will sim­ply be found dead. As the or­gan­ism mul­ti­plies in the blood stream, it blocks the blood ves­sels, caus­ing raised, di­a­mond-shaped or oval blotches which can be pink, dark red, or pur­ple. The le­sions fi­nally turn black as skin tis­sue dies. In the chronic form of the dis­ease, arthri­tis de­vel­ops in the joints and in­fec­tion of the heart valves can cause heart fail­ure.

Pre­ven­tion and cure

Vac­ci­na­tion: As erysipelas is so wide­spread and so po­ten­tially dam­ag­ing, vac­ci­na­tion is rec­om­mended. Peni­cillin is ef­fec­tive against erysipelas if it is di­ag­nosed at an early enough stage, but vac­ci­na­tion against it is a much more sen­si­ble course of ac­tion. The most com­mon vac­cine is Por­cilis® Ery. Breed­ing stock should be given an ini­tial course of two sep­a­rate vac­ci­na­tions, four weeks apart, fol­lowed by booster vac­ci­na­tions ev­ery six months or dur­ing each lac­ta­tion. Boars and gilts should be vac­ci­nated at least two weeks be­fore mat­ing.

Treat­ment: As stated above, erysipelas can be tack­led ef­fec­tively with peni­cillin if di­ag­nosed suf­fi­ciently early. In acute cases, a fast-act­ing peni­cillin in­jected twice in the first 24 hours should be given, fol­lowed by daily in­jec­tions for three to four days. In non-acute cases, pigs can be treated with a long-act­ing type.

Porcine par­vovirus (PPV)

An­other pre­ventable re­pro­duc­tive dis­ease is porcine par­vovirus. This kills devel­op­ing piglets in the uterus and is widely be­lieved to be the most com­mon and most sig­nif­i­cant cause of re­pro­duc­tive fail­ure. Around 90% of breed­ing herds in the UK have it. It is trans­mit­ted through the nose or mouth, passes into the in­tes­tine and is shed in fae­ces. Within three weeks of in­fec­tion, it crosses the pla­centa and at­tacks the devel­op­ing em­bryos and foe­tuses.

Un­like most viruses, PPV is in­cred­i­bly re­silient and can sur­vive out­side of a pig for sev­eral months. It is also re­sis­tant to most dis­in­fec­tants. Its ef­fects de­pend on the stage of preg­nancy. Gilts are most sus­cep­ti­ble to PPV at around four or five months old when ma­ter­nal an­ti­bod­ies start to de­cline. They should ide­ally be vac­ci­nated at five months old and al­ways be­fore be­ing put to the boar for the first time. Sows de­velop im­mu­nity either by vac­ci­na­tion or through phys­i­cal ex­po­sure to the virus, but there can be ex­cep­tions. Boars, too, need to be vac­ci­nated. Al­though PPV does not have a detri­men­tal ef­fect on se­men qual­ity, the virus can still be trans­mit­ted in boar se­men.

Pro­tec­tion against PPV

Por­cilis® Ery + Parvo is a com­bined vac­cine which pro­tects against both PPV and erysipelas. The man­u­fac­turer rec­om­mends vac­ci­nat­ing all breed­ing stock, either at wean­ing, or at least two weeks be­fore mat­ing. A sin­gle in­jec­tion prior to mat­ing should pro­tect against PPV, but to achieve pro­tec­tion against erysipelas as well a fur­ther in­jec­tion should be given four weeks later, with either the com­bined vac­cine or the erysipelas-only ver­sion. As men­tioned ear­lier, sows should be re­vac­ci­nated against erysipelas dur­ing each lac­ta­tion pe­riod (or ev­ery six months), but PPV re­quires just an an­nual booster.

Liz Shank­land is the au­thor of the Haynes Pig Man­ual and she teaches cour­ses in small­hold­ing and pig hus­bandry at Hum­ble by Na­ture (www.hum­ble­by­na­ture.com).

A healthy lit­ter of pigs

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