Monthly Archives: August 2011

This study investigated the growth and immune responses of pigs fed diets containing reduced concentrations of aflatoxin (AF) and deoxynivalenol (DON) from naturally contaminated corn. Sixty gilts (13.9 ± 0.2 kg of BW) were randomly assigned to 4 treatments (5 replicate pens per treatment and 3 pigs per pen): A (a control diet without detectable AF and DON); B (a diet with 60 μg of AF/kg and 300 μg of DON/kg); C (a diet with 120 μg of AF/kg and 600 μg of DON/kg); and D (a diet with 180 μg of AF/kg and 900 μg of DON/kg). Pigs were allowed ad libitum access to feed and water for 33 d. Feed intake and BW were measured weekly and pigs were bled (8 mL) on d 33 to measure the numbers of blood cells, to conduct liver function tests, and to measure immunological variables including IgG, IgM, interferon γ, IL4, IL6, and tumor necrosis factor α. One pig representing the average BW of each pen was killed to obtain the liver, kidneys, and spleen for weight, tissue color measurement, and histological evaluation of tissue damage. When compared with A, pigs in C and D tended to have reduced ADG (0.52 vs. 0.43 and 0.41 kg/d, respectively; P = 0.058) and ADFI (1.04 vs. 0.92 and 0.88 kg/d, respectively; P = 0.061). White blood cell count of pigs in D (23.4 x 10(3) cells/μL) was greater (P < 0.05) than those in A, B, and C (18.4, 18.5, and 16.8 x 10(3) cells/μL, respectively. Serum tumor necrosis factor α concentration of pigs in D (335 pg/mL) differed (P < 0.05) from those in A and C (299 and 290 pg/mL, respectively). Pigs in B and D had greater (P < 0.05) fibrosis in liver tissues than those in A. Collectively, this study shows that diets containing both AF and DON greater than 60 and 300 μg/kg, respectively, may reduce growth and decrease feed intake, whereas diets containing 120 μg of AF/kg and 600 μg of DON/kg may result in altered immune health, systemic inflammation, and partial liver damage, causing further reduction in growth of pigs.

Porcine Circovirus Type 2 (PCV2) is the obligate infectious agent in Postweaning Multisystemic Wasting Syndrome (PMWS) of pigs. To control PMWS we vaccinated dams twice, 4 and 2 weeks before pregnancy and once in the 12th week of gestation with an inactivated PCV2 vaccine (Circovac®). Two producer farms run under the control of Swiss Swine Health Organisation were selected for the experiment. Previously, in one farm PMWS was diagnosed after weaning, whereas in the other farm, pigs wasted during the fattening period. For the experiments 113 dams were randomly vaccinated and 111 dams were sham injected. Vaccination increased serum antibodies in dams 3-9 fold accompanied with serum antibody titer increase in their offspring. In the 6th week of life, progeny from vaccinated dams had about the same IgG antibody titer as progeny of unvaccinated dams at the third day of life. In sera of vaccinated dams only low concentration of PCV2 DNA was detected and no progeny developed PMWS. Interestingly, at day 56 four progeny of unvaccinated dams were tested positive for anti-PCV2 IgM antibodies indicating a primary infection with PCV2. Of economical importance, progeny of vaccinated dams had a significant higher daily weight gain in the fattening period (farm X +51 gr/d; farm Y +30 gr/d) and thus a shortened fattening period of about 6 days compared to progeny of controls. To our knowledge this is the first demonstration of subclinical circovirus infection and its effects on growth performance of fattening pigs by vaccination of dams. Kurmann J, Sydler T, Brugnera E, Buergi E, Haessig M, Suter M, Sidler X; Vaccination of dams increases antibody titer and improves growth parameters in finisher pigs subclinically infected with PCV2; Clin Vaccine Immunol. 2011 Aug 18. [Epub ahead of print]