Impact of agitation time of boar semen doses on sperm traits in short- and long-term extenders.

Transport of extended boar semen doses is a common practice in the swine industry. This study aimed to verify the effect of agitation time on sperm parameters during storage in two semen extenders. One normospermic ejaculate from each boar (n = 20) was diluted in a split sample design with long-term (LONG, Androstar® Plus) and short-term (SHORT, Beltsville Thawing Solution) extenders. Extended semen doses were filled with a total volume of 45 mL and 1.5 billion sperm cells and submitted to 0, 3, 6, and 12 h of agitation in an orbital shaker at 70 rpm. The samples were stored at 17 °C for 120 h. Sperm parameters were evaluated for sperm motility, plasma membrane integrity, pH, thermo-resistance test (TRT), oxidative stress status, and mitochondrial membrane potential. Total and progressive motility were affected by the interaction between the agitation time and the extender, with a linear reduction in sperm motility as the agitation time increased for LONG extender (P ≤ 0.05). Semen doses diluted with SHORT showed a higher pH (P < 0.01), and agitation time had a positive quadratic effect with the highest pH observed after 6 h of agitation, regardless of the extender used (P < 0.01). Sperm motility after TRT and plasma membrane integrity potential were not affected by agitation time (P > 0.05). Mitochondrial membrane potential and oxidative stress status quadratically decreased as agitation time increased (P ≤ 0.05). Based on the results, long transport durations of AI doses under mild vibration emissions affect boar semen quality.

Molecular detection of respiratory coinfections in pig herds with enzootic pneumonia: a survey in Brazil.

Mycoplasma hyopneumoniae is the primary etiologic agent of swine enzootic pneumonia (EP), in which the immune response is reduced, making pigs susceptible to secondary infections. We surveyed commercial pig herds in Brazil for viral and bacterial respiratory coinfections that could complicate EP. Over a 2-y period (2015-2016), we found that 854 of 2,206 pigs (38.7%) were positive for M. hyopneumoniae in herds from various production systems in 3 Brazilian regions (Central-West, Southeast, South). We collected samples of 321 lungs positive for M. hyopneumoniae from 169 farms to also screen for Pasteurella multocida, Actinobacillus pleuropneumoniae, Glaesserella parasuis, influenza A virus (IAV), and porcine circovirus 2 (PCV2) by real-time PCR. The prevalence of pathogens found in addition to M. hyopneumoniae varied: P. multocida (141; 43.9%), G. parasuis (71; 22.1%), PCV2 (50; 15.6%), IAV (23; 7.2%), and A. pleuropneumoniae (18; 5.6%). G. parasuis was more frequent in farrowing or nursery herds (48.7%) than in breeding and fattening herds (10% and 18.6%, respectively; p < 0.01); A. pleuropneumoniae was found only in herds on farrow-to-finish and fattening farms.