Ascariasis, Respiratory Diseases andProduction Indices in Selected Prince EdwardIsland SwineHerds

Thelevels ofproduction, ascarid burdenandrespiratory disease were measured on 15purposively selected swineherds, andtherelationships betweenthevarious measures of ascarid burdenwere examined. On eachfarm30randomly selected pigs wereweighed andrectal fecal samples were collected atapproximately 11, 15,19and22weeksofage,andat slaughter. Fecalascarid-egg counts and durationof infection were combined tocalculate a composite measure ofascarid burdencalled "lifetime burden". Attheabattoir the carcass weightand levelsof anteroventral pneumonia, atrophic rhinitis, and liverlesions were recorded foreachhog.Thenumberof ascarids inthesmallintestines were counted. Studyhogsweremarketed at an averageof189± 22days.The averagedressed carcassweight was 77.0 ± 5.9kgandthemean average daily gain was 0.519 ± 0.071 kg/day. Thepercent ofhogswithascariasis varied widely among farms, no matter whatmeasure ofascariasis was used; thepercent withintestinal ascarids at slaughter ranged from0%to96%,the percent thatshedascarid eggsduring their lifetime ranged from0%to100%, andtherange forhogswithliver lesions ranged from27%to100%.Of thehogsslaughtered, 82%hadmilk spotlesions, 32%shedascarid eggs duringtheir lifetime and35% had intestinal ascarids. Thelatter hadan average of 12 intestinal ascarids. Anteroventral pneumonia occurred in 55%oftheslaughtered hogsand9% hadatrophic rhinitis scoresoffive. Thepercent ofhogsper farmwith pneumonia ranged from17%to96%. Thepercent ofhogsper farmwith atrophic rhinitis scoresoffive ranged from0%to57%. RESUME Quinzeelevages deporcsfurent choisis pour leurtauxdeproduction ainsi quepourlapresenced'Ascaris et demaladies respiratoires. Parlasuite on examinalesrelations pouvant exister entre lesdifferentes indications delacharge parasitaire. Surchacune desfermes, on selectionna au hasard 30sujets; aux agesde11,15,19et22 semaines, ainsi qu'au moment de l'abattage, chaqueanimal futpeseet un echantillon defumier futpreleve directement du rectum.En tenant comptealafois delaponteparasitaire etdeladureedinfection, on putainsi calculer la"charge parasitaire avie". A l'abattoir, on nota,pour chaque animal, lepoidsdelacarcasseainsi que lestauxdepneumonie anteroventrale, derhinite atrophique etde lesions hepatiques; on comptaaussi le nombred'Ascaris danslepetit intestin. Cesanimauxarriverent surle marchea l'ige moyen de189± 22 jours; lepoids moyen deleur carcasse futevalue a77,0 ± 5,9kg,etleurgain depoids moyen journalier, a0,519 + 0,071kg/jour. Le pourcentage de porcsavecdel'ascariase varia grandementd'unefermea l'autre independammentdutestdedepistage utilise: ainsi, on detecta desAscaris dans lintestin de0a96%desanimaux, 0a 100%desanimauxexcreterent des oeufsd'Ascaris a un moment ou I'autre deleur vieet27a100%d'entre eux presenterent deslesions hepatiques. Dansl'ensemble, l'incidence desporcspresentant des"taches de lait" s'est etablie a 82%,celle des animaux excretant desoeufs d'Ascaris durant leur viea32%etcelle dessujets avecdesAscaris dansl'intestin a35%. Lenombremoyen desAscaris futde douze. Lapneumonie antero-ventrale futdetectee chez55% desporcs abattus etlarhinite atrophique de classe cinqchez9%.Dix-sept a 96% desporcsparfermepresenterent dela pneunomie et0 a 57%delarhinite atrophique declasse cinq.