Reproductive performance and uterine prostaglandin secretion in gilts conditioned with dead semen and receiving dietary supplements of folic acid

Abstract

. 2000. Reproductive performance and uterine prostaglandin secretion in gilts conditioned with dead semen and receiving dietary supplements of folic acid. Can. J. Anim. Sci. 80: 467-472. The effects of dietary supplements of folic acid at 0 (F-) or 15 ppm (F+) and of conditioning the uterus (C+) or not (C-) with an intrauterine infusion of dead semen on embryonic survival and prostaglandin E2 (PGE 2 ) concentrations in the allantoic fluid on day 30 of gestation were studied. Sixty-four F 1 crossbred gilts (Yorkshire × Landrace) were used in a 2 × 2 factorial design. The initiation of folate supplementation and the intrauterine infusion of dead semen were done at the estrus preceding the fertile mating. Folate status in serum was lower in F+ gilts than in F-gilts during the estrus cycle (folic acid × period interaction, P ≤ 0.007). Conditioning increased ovulation rate in F-gilts while it tended to decrease it in F+ gilts (interaction folic acid × conditioning, P ≤ 0.03). A similar interaction (P ≤ 0.02) was observed on the number of presumably live embryos at 30 d of gestation. Mean PGE 2 concentration in the allantoic fluid was not affected by treatments (P ≥ 0.44), but the frequency of sows having elevated allantoic PGE 2 (> 4 ng mL -1 ) tended to be higher (P ≤ 0.06) in F+ sows. Overall values of PGE 2 were correlated with total litter weight (R 2 =0.54). In conclusion, there was no synergism between folic acid supplements and conditioning of the uterus with dead semen on the reproductive performance or on the secretion of allantoic PGE 2 at 30 d of gestation. The secretion of allantoic PGE 2 appears as an important factor involved in the control of litter size and weight. infusion intra-utérine (C+) ou non (C-) de semence morte ont été mesurés sur la survie et le développement embryonnaire ainsi que sur la sécrétion utérine de prostaglandine E 2 (PGE 2 ) à 30 jours de gestation. A cet effet, soixante-quatre cochettes F 1 (Yorkshire-Landrace) ont été distribuées dans des traitements factoriels 2 × 2. L'infusion intra-utérine de semence morte et le début de la supplémentation en folate ont été faites à l'oestrus précé-dant la saillie fertile. Les concentrations de folates sériques étaient plus basses chez les truies F+ que chez les F-pendant le cycle oestral précédant la saillie féconde (interaction acide folique × période, P ≤ 0,007). Le conditionnement utérin a provoqué une augmentation du taux d'ovulation chez les cochettes F-alors qu'une diminution était observée chez les F+ (interaction acide folique × conditionnement, P ≤ 0,03). Une interaction similaire (P ≤ 0,02) a été observée sur le nombre d'embryons présumés vivants à 30 jours de gestation. Aucun effet (P ≥ 0,44) des traitements n'a été observé sur la PGE 2 dans le liquide allantoïdien mais la fréquence des taux supérieurs à 4 ng mL -1 avait tendance à être plus élevée (P ≤ 0,06) chez les truies F+ vs F-. Les valeurs de PGE 2 étaient corrélées avec le poids de la portée (R 2 = 0,54). En conclusion, il semble qu'il n'y ait pas d'avantage à combiner u...

Novel insights into the mechanisms of pregnancy establishment: regulation of prostaglandin synthesis and signaling in the pig

“…Identification of the PGE 2 receptors PTGER2 and PTGER4 in the porcine endometrium (Waclawik et al 2009a) and in the conceptus (Waclawik et al 2008b) indicates that PGE 2 could act directly to promote uterine function, as well as conceptus development and migration in the uterus (Pope et al 1982, Geisert et al 1990, Giguère et al 2000. PGE 2 is implicated in the local increase in endometrial vascular permeability and preparation for angiogenesis and implantation (Hamilton & Kennedy 1994, Kennedy et al 2007.…”

Folic acid and vitamin B12 in reproducing sows: New concepts

“…Moreover, besides endometrial synthesis, which is the main source of PGE 2 , conceptuses have the ability to synthesize prostaglandin as early as days 7 to 11 of pregnancy (Lewis 1989) depending on the local presence of the precursor arachidonic acid (C20:4n-6) (Davis et al 1983) and the activity of the enzyme involved in prostaglandin synthesis, i.e., cyclooxygenase (COX) (Wilson et al 2002). During the post-attachment period, variations of PGE 2 concentration in allantoic fluid have been positively associated with litter weight variations on day 30 of gestation in sows (Giguère et al 2000). It is also known that the concentration of intrauterine PGE 2 in Chinese hyperprolific Meishan, known for their low embryo mortality, is higher than in occidental Yorkshire-Landrace sows at the beginning of gestation (Bazer et al 1991).…”

“…Dietary supplements of vitamin B 9 have been found to increase the uterine concentration of PGE 2 during conceptus attachment (days 12 to 15 of gestation) in sows Duquette et al 1997) and the concentration in allantoic fluid later in gestation (day 25) (Giguère et al 2000;Guay et al 2004b). Nevertheless, endometrial PGE 2 does not always respond to dietary supplementation with vitamin B 9 (Guay et al 2004a).…”

“…The dietary supplement of B 9 was 1 ppm. y Adapted from Giguère et al (2000). The dietary supplement of B 9 was 15 ppm.…”

“…elucidated since B 9 supplementation has been reported to produce no response or only attenuated responses in terms of litter size and embryo survival (Harper et al 1994;, especially in nulliparous sows (Lindemann and Kornegay 1989;Matte et al 1992Matte et al , 1993Giguère et al 2000;Guay et al 2002a). This influence of parity has also been reported for conceptus secretion of E 2 (data not shown), uterine levels of PGE 2 (Duquette et al 1997) and uterine levels of TGFβ 2 (Guay et al 2004b) (Table 1).…”