A meta-analytical study about the relation of blood plasma addition in diets for piglets in the post-weaning and productive performance variables

AbstractThe meta-analysis was used to evaluate the performance of piglets in post-weaning period, without imposition of sanitary challenge and fed diets containing blood plasma, obtained by spray-dried process (SDBP). Piglets are faced with normal challenges in post-weaning period such as environmental stress and the substitution of the liquid diet to a solid one. References regarding sanitary challenges were disregarded in this study. Only data regarding normal and expected challenges were considered. Data were obtained from indexed journals with information extracted from the material, methods and results sections of pre-selected scientific articles. First, the database was analyzed graphically to observe the distribution of data and presence of outliers. Afterwards correlation analysis and variance–covariance analyses were carried out. The database contained a total of 23 articles. The average initial weight of the piglets was 8.02kg (4.00–9.28kg) and the average initial age was 27 days (14–32 days). The average duration of feeding diets containing spray-dried blood plasma (SDBP) was 9 days (6–28 days). SDBP increased the feed conversion by 20.2% (P<0.05) during the initial period. Feed conversion during the total period was 10.2% higher (P<0.05) for animals fed with SDBP. Average daily weight gain and daily feed intake were not affected (P>0.05) during the entire period, but average daily gain was higher (P