Neither frozen-thawed seminal plasma nor commercial transforming growth factor-β1 infused intra-utero before insemination improved fertility and prolificacy in sows.

Seminal plasma (SP) affects reproduction, inducing cell and molecular changes in the female genital tract. A main active component in SP is the modulatory transforming growth factor-β (TGF-β), particularly its TGF-β1 isoform, which affects the synthesis of other cytokines as granulocyte-macrophage colony-stimulating factor, relevant for embryo development and pregnancy. This study evaluated the effect of pooled frozen-thawed SP and commercial TGF-β1 infused during oestrus in sows post-cervically inseminated with liquid extended semen, containing ~4 ml of residual SP, on their fertility and prolificacy. For this, 250 sows in their post-weaning oestrus were used. Sows were randomly assigned to one of the following groups to be post-cervically treated 30 min before insemination: (i) SP group: infused with 40 ml of SP (N = 57); ii) Group TFG ß1 : infused with 40 ml of BTS extender containing 3 ng/ml of porcine TGF-β1 (N = 64); iii) BTS group: infused with 40 ml of BTS extender (N = 60); and iv) Control Group: sows catheterized but not infused prior to AI (N = 69). Farrowing rates (range: 86.7% to 91.3%) and numbers of live-born piglets (range: range: 12.8 ± 2.9 to 13.4 ± 3.1) were not affected by any treatment compared with Controls, indicating that neither pre-infusions of SP nor TGF-ß1 30 min before AI influenced subsequent fertility and prolificacy.