An investigation into uterine capacity based on litter and placental characteristics in two sow lines with different prolificacy (Danish Landrace x Danish Yorkshire versus German Saddleback).

Litter size in modern so called hyperprolific pig (Sus scrofa Linnaeus) breeds such as of crossbred Danish Landrace x Danish Yorkshire (LY/YL) sows increased remarkably over recent years, however, commonly associated with reduced piglet birth weight and higher within litter birth weight variability likely due to a limited uterine capacity. Since investigation into this issue is patchy, the aim of this study was to investigate uterine capacity based on litter and placental characteristics in two sow lines with different prolificacy, that is crossbred Danish genetic (Danish Landrace x Danish Yorkshire; DG; n = 14) and purebred German Saddleback (GS) sows (n = 12). Parameters recorded were litter size, piglet birth weight and vitality, placental weight and surface area as well as placental vascularization. Litters of DG were on average larger than of GS (p < .001). Piglets of DG weighed on average less than GS (p < .001) and were less vital (p < .001-.142). Increasing litter size was associated with reduced piglet birth weight and increased within litter birth weight variability in GS, but not in DG. DG had on average a lower placental weight (p < .001) and smaller placentae (p < .001) than GS, but the placenta was on average more efficient than of GS (based on the quotient of piglet and corresponding placental weight; p < .001). Vascularization of placentae was on average not or only slightly different between breeds (p < .05 - .982). Remarkably, however, vascularization of the lateral and apical chorionic epithelium of the chorionic ridges as the immediate foetal/maternal interface was on average slightly higher in DG than GS (p < .05-.111). Results thus demonstrate that uterine capacity based on litter and placental characteristics is higher in DG than GS sows.

[Management of large litters in piglet production]. / Management großer Würfe in der Ferkelerzeugung.

In recent years, the number of live-born piglets per litter has increased tremendously. Litters of 15 or even up to 20 piglets are no longer uncommon. Due to this increased fertility, the demands placed on the sows rise as they are expected to rear a large number of healthy and vital piglets until weaning. On the other hand, there is also a higher demand for good management of the sows and litters during the lactation period. To reduce piglet losses, to achieve a high growth performance of piglets in large litters and to maintain the lactating sows in good health and body condition, sows and piglets need to be supported by different management activities during the entire lactation period, which are presented in this article.

Perinatal zearalenone exposure affects RXFP1, RXFP2, and morphoregulatory gene expression in the neonatal porcine uterus.

The mycotoxin zearalenone (ZEA) is a selective estrogen receptor modulator that can contaminate cereal feeds and lead to reproductive disorders. To determine effects of perinatal ZEA exposure on uterine expression of genes associated with endometrial development in the neonatal gilt, pregnant sows were fed ZEA (1500 microg ZEA/kg of feed/day) or vehicle from 14 days before farrowing through postnatal day (PND) 20-21, when neonatal uterine tissues were collected. At birth, gilts were cross-fostered to generate four ZEA exposure groups (n= 5-6/group): unexposed controls or exposures limited to prenatal, postnatal, or pre- and postnatal (continuous) periods. Results showed that at PND 20-21, uterine Wnt7a, Hoxa10, estrogen receptor alpha, and RXFP2 mRNA levels were decreased in neonates exposed continuously to ZEA (P < 0.05). Uterine RXFP1 transcripts were decreased in postnatally and continuously exposed groups (P < 0.05). Neonatal uterine Wnt4 mRNA levels were unchanged.

Laser microdissection of neonatal porcine endometrium for tissue-specific evaluation of relaxin receptor (RXFP1) expression in response to perinatal zearalenone exposure.

Porcine neonatal uterine relaxin receptor (RXFP1) expression is tissue compartment specific and estrogen sensitive. Here, procedures were established for laser microdissection, tissue capture, and quantification of the effects of perinatal exposure (14 days pre- to 21 days postnatal) to a selective estrogen receptor modulator of environmental origin, zearalenone (ZEA), on endometrial RXFP1 expression. Total RNA from captured endometrium was used to generate cDNA for quantitative reverse transcription-PCR. Cycle threshold values indicated that ZEA reduced (P < 0.06) endometrial RXFP1 expression on postnatal days 20-21.

[Influence of different copper and zinc supply on their concentrations in blood serum, liver and hair of dairy cows]. / Einfluss unterschiedlicher Kupfer- und Zinkversorgung auf deren Konzentrationen in Blutserum, Leber und Deckhaar bei Milchkühen.

In a feeding trial at the Institute of Animal Nutrition of the Federal Research Institute of Animal Health (FLI) over 12 weeks with 20 cows of the German Holstein Breed the influence of different copper and zinc contents in the ration on their concentration in blood serum, liver and hair was tested. All animals received a diet based on maize- and grass silage ad libitum. The animals were divided in two groups with 10 cows each; group A received a concentrate according to their milk yield with a copper and zinc content as recommended (GfE 2001), whereas group B was offered a concentrate with roughly the double amount of copper and zinc. At the beginning and at the end of the trial a sample of blood, pigmented hair and a liver bioptate was taken from all animals to evaluate the incorporation of copper and zinc in these tissues. In serum and pigmented hair the copper concentrations did not differ between the two groups [13.4 for Group A and 12.5 micromol/L for Group B in serum respectively 6.8 (Group A) and 7.4 mg/kg DM (Group B) in pigmented hair]. Only the copper concentration in the liver was influenced by the different feeding. The higher copper content for group B resulted in a significantly higher copper concentration in the liver (506 mg/kg DM compared to 383 mg/kg DM). The liver is the best indicator organ for a sufficient copper supply. An increase in the zinc content in the ration resulted neither in higher zinc concentrations in serum (15.1 in Group B in comparison to 13.4 micromol/L for Group A) nor in higher zinc concentrations in liver (140 for Group B and 112 mg/kg DM for Group A) and pigmented hair (130 in Group A and 123 mg/kg DM in Group B). There is a significant correlation between copper intake and copper concentration in the liver (r = 0.46), whereas the correlation between zinc intake and zinc concentration in the liver is only tendencially (r = 0.23). The three tested samples serum, liver and cow hair are not qualified to reflect exactly a sufficient zinc supply.