Utjecaj infekcije virusom AEK na proizvodnju mlijeka francuske alpske koze u Hrvatskoj

We have investigated the influence of infection with Caprine Arthritis Encephalitis Virus (CAEV), developed clinical arthritis and recorded subclinical mastitis on the length of lactation, milk yield and its composition per lactation. The study was carried out on the sample of 808 goats of French Alpine breed from production farms in Croatia. Samples of blood were taken for serological tests and milk samples for subclinical mastitis detection. Presence of clinical arthritis was noted by inspection and palpation of the joints. Lactation and production data were collected by Croatian Agricultural Agency. The influence of infection status for CAEV and clinical arthritis, separately, were tested on milk yield, length of lactation and milk composition (fat, protein and lactose) using GLM procedure for models including the year of measurement, lactation number of the animal and subclinical mastitis record. CAEV was serologically confirmed in 53.72 % of the total number of goats. From the total sample 23.08 % were infected with CAEV with confirmed subclinical mastitis of bacteriological etiology. In addition, 22.47 % of the total sample had clinical arthritis. Of the total sample 16.95 % were CAEV infected and with diagnosed clinical arthritis. Influence of virus infection was confirmed on all of the analyzed traits, with lower production results. Clinical arthritis had significant influence on decrease in most of analyzed traits, exceptions being total milk, fat amount (%) and lactose content (%) and amount (kg). Diagnosed subclinical mastitis was not found to be significant influence in models of duration of lactation, or fat, protein and lactose content (%).Istraživan je utjecaj infekcije virusom artritis encefalitisa koza (AEK), kliničkog artritisa i subkliničkog mastitisa na trajanje laktacije, ukupno mlijeko i sastav mlijeka. Istraživanje je provedeno na uzorku od 808 koza pasmine francuska alpska koza s proizvodnih mliječnih farmi u Hrvatskoj. Uzeti su uzorci krvi za serološka testiranja i uzorci mlijeka za detekciju subkliničkog mastitisa. Prisutnost kliničkog artritisa dijagnosticirana je pregledom i palpacijom zglobova. Podaci o laktacijama i proizvodnji preuzeti su od Hrvatske poljoprivredne agencije (HPA). Zasebno su testirani utjecaji AEK infekcije i kliničkog artritisa na ukupno mlijeko, trajanje laktacije i sastav mlijeka (mast, protein, laktoza) pomoću GLM procedure za modele koji su uključivali godinu mjerenja, broj laktacije i subklinički mastitis. Infekcija AEK virusom potvrđena je u 53,72 % koza od ukupnog broja koza. Od ukupnog uzorka 23,08 % inficirano je s AEK i imalo subklinički mastitis bakterijske etiologije. Nadalje 22,47 % od ukupnog broja imalo je klinički artritis. Od ukupnog broja 16,95 % bilo je AEK pozitivno i imalo klinički artritis. Utjecaj infekcije virusom AEK potvrđen je za sva analizirana svojstva u smislu smanjenja proizvodnih rezultata. Klinički artritis je pokazao značajan utjecaj na smanjenje većine proizvodnih vrijednosti osim na ukupno mlijeko, udio (%) masti laktoze i ukupnu laktozu (kg). Subklinički mastitis nije značajno utjecao na trajanje laktacije, kao ni udio (%) i udio masti, proteina i laktoze