Influence of growth rate, backfat thickness and meatiness on reproduction efficiency in Landrace gilts

Abstract

ABSTRACT:In the nucleus herd and subsequent multiplication herd of the Landrace (L) breed in 262 gilts farrowed after the first insemination we analysed the influence of various levels of average daily weight gain from birth in the performance test in the field (ADG1) and till mating (ADG2), average backfat thickness (mm) in the performance test (BF1) and at mating (BF2) or lean meat percentage (LM1 and LM2) on the age and weight at mating and at farrowing, on the number of piglets born, piglets born alive and weaned ones and litter weight at 21 days. Based on the studied traits the gilts were divided into intervals for the evaluation according to the average and standard deviation (≤ x -s; x -s; x + s; ≥ x + s). A significant influence of ADG1 and ADG2 on the weight at the first insemination was observed (P < 0.01, P < 0.001). The age and weight after farrowing were affected by ADG1 to a greater extent (P < 0.001). With increasing values of weight gain a higher number of piglets per litter was observed. ADG1 affected the number of piglets born and also of piglets born alive (P < 0.001), the litter weight at 21 days (sows' milk production) and the number of weaned piglets (P < 0.05). ADG2, however, affected only the number of piglets born and of piglets born alive per litter (P < 0.05, P < 0.001). BF1 affected only the age at the first insemination or at farrowing (P < 0.05) and the number of piglets at the age of 21 days (P < 0.05). BF2 affected the number of piglets born, those born alive and the weaned ones (P < 0.05, P < 0.01), the litter weight at 21 days (P < 0.001) and the number of piglets at 21 days (P < 0.05, P < 0.01). The lean meat percentage ascertained in the performance test (LM1) did not significantly affect any studied reproduction trait. A significant influence of LM2 on the age at the first insemination or at farrowing was proved (P < 0.05, P < 0.01) as well as on the weight at the first fertile insemination (P < 0.001). An increased percentage of lean meat had a negative impact on the number of piglets born and piglets born alive (P < 0.05), on litter weight at 21 days (P < 0.01), number of piglets at the age of 21 days (P < 0.001) and on the number of weaned piglets (P < 0.05, P < 0.01). A more significant influence of the higher growth ability of gilts on the reproductive traits was detected in the performance test. On the contrary, at the period of mating the reproductive traits were affected by backfat thickness and meatiness to a greater extent.

Comparative performance of Landrace, Yorkshire and Duroc breeds of swine

“…Różycki (2003) proposed that result of the performance test was one of the main criteria in the selection of pig for breeding and livestock production. Some author use performance traits for the evaluation of growth ability, others use parameters from testing stations (Bečková et al, 2005;Kernerová et al, 2006;Michalska et al, 2014). Therefore, an evaluation of the livestock in advance is very important to know the conditions in which animal are kept before any definite recommendations can be made.…”

Correlation of carcass meat content with development of the reproductive system in sexually immature gilts

“…Kerr and Cameron (1995) indicated that selection for lean growth on either an ad libitum or a restricted feeding regime did not significantly affect reproductive performance, while animals in lines with high lean feed conversion ratio or low daily feed intake had reduced reproductive performance. The results obtained by Bečková et al (2005) on a group of Landrace gilts suggest that reproductive performance is more determined by growth rate and backfat thickness than by meat content. On the other hand, according to other researchers there is no correlation between meatiness and reproductive performance traits such as fertility, the number of piglets born alive in a litter or the number of piglets reared (Čechová et al, 2000;Bocian et al, 2010).…”

Comparison of changes in fatness of sows in high pregnancy and at weaning and determination of their association with reproduction results and rearing of piglets

“…As a result, multiparous sows showed better productivity. Smaller fat reserves are undesirable, especially for primiparous sows (Amaral Filha et al, 2010;Bečková et al, 2005;Kawęcka et al, 2009;Roongsitthichai et al, 2011). Young females undergo ontogenetic changes and the production process (pregnancy and rearing of the litter) puts an enormous strain on their body; this concerns both multiparous sows and sows in the second reproductive cycle, which still undergo somatic development.…”

“…Body condition depends on nutrition and shows an association with reproductive traits (Beyga and Rekiel, 2010;Čechová and Tvrdoň, 2006;Maes et al, 2004;Young et al, 2004;Wähner et al, 2001). The correlations between growth rate, fat reserves and meat content at mating and reproductive results of gilts are known quite well (Amaral Filha et al, 2010;Bečková et al, 2005;Kawęcka et al, 2009;Roongsitthichai et al, 2011). Less study has been given to the issues concerning changes in fat reserves from high pregnancy to weaning, and their relationship with reproductive performance and rearing of piglets from primiparous and multiparous sows.…”