The effect of feeding system and sex on the performance and selected gastrointestinal features of fattening pigs.

The aim of the study was to evaluate the efficiency of two feeding systems for fattening pigs (wet and dry), taking into account their sex, on performance, nutrient digestibility, and some histological and microbiological parameters of the gut. The study was conducted on 450 fattening pigs, divided into 6 groups (n = 75) and housed in pens with 15 pigs per pen. The first three groups, divided according to sex, i.e. gilts, barrows and boars subjected to immunocastration (B-I), received complete dry feed, while the next three, divided in the same manner according to sex, were fed a fermented liquid diet. The nutritional value of the feeds, calculated on a dry weight basis, was similar for the two feeding systems in both stages of the fattening period. The best weight gains were observed in the group B-I pigs which received the liquid diet, and the poorest in the gilts fed the dry feeds. The best feed conversion ratio (FCR) was observed in the boars treated with Improvac®, especially those receiving the liquid diet. The feeding system significantly influenced the digestibility of nutrients, with higher apparent digestibility coefficients for crude protein, fat and fibre noted in the animals fed in the wet system. The liquid feeding system caused an increase in crypt depth in the colon in all groups of pigs, as well as an increase in the width of the muscular layer. A significant decrease in the total bacterial count was observed in the calcium, especially in the animals fed in the wet system.

Influence of long-term vaccination of a breeding herd of pigs against PCV2 on reproductive parameters.

The objective of the study was to evaluate an efficacy of sows vaccination protocols in the herd with serious problems affecting efficacy of reproduction. The study was performed in a large pig herd with about 1200 sows. Before vaccination against PCV2, farrowing rate in this farm was about 65%. Sows, boar and replacement gilts were immunized using Circovac vaccine (Merial, France) according to producer's recommendations. Parameters of production were analyzed since 2007 until 2010 in selected batches of sows inseminated at the same weeks of the year (17th, 18th, 19th and 20th) to eliminate seasonal variability. In total, 940 sows were subjected to the study. No significant changes in management during these years were introduced. The applied protocol of sow herd long-term vaccination proved to be very efficient. All measured production parameters: reproduction rate, number of piglets born alive, birth weight of piglets and number of piglets weaned per a litter improved after implementation of immunization program. Moreover, further improvement was observed with vaccination in the following reproduction cycles. The most spectacular effect of vaccination regarded average farrowing rate that increased from 64.76% in control group to 86.93% after basic vaccination. Two years after implementation of vaccination program this parameter reached 93.6%. Number of piglets weaned per sow per a litter improved from 10.31 to 11.74 after one year of vaccination and remained relatively stable through the following year. Simultaneously, the percentage of newborn piglets with birth weight < 1 kg decreased significantly (p < 0.05). To summarize, vaccination against PCV2 influenced positively the insemination rate, number of piglets born alive and weaned per litter as well as birth body weight and percentage of piglets weighing < 1 kg.