The aim of this study was to investigate whether plasma anti-Muellerian hormone (AMH) levels of Holstein-Friesian heifers could be used to predict ovum pick-up (OPU) and embryo production outcomes. Plasma samples and data were collected from 64 heifers, which underwent repeated OPU with subsequent in vitro embryo production followed by embryo flushing after superovulation. AMH levels were significantly positively correlated with the number of follicles aspirated per OPU session (r = 0.45), recovered oocytes per OPU (r =0.43) and in vitro produced embryos per OPU (r = 0.28). No significant correlations between AMH and in vivo produced embryos were ascertained. Our results suggest that correlations between AMH and outcomes of an OPU-IVF program are too low to use AMH as a precise predictive parameter for the success of a particular OPU procedure in Holstein-Friesian heifers. However, AMH can help to identify groups of very good or very poor oocyte donors.

The innate immune system has numerous mechanisms to fight against pathogens, including the formation of neutrophil extracellular traps (NETs). By spreading out chromatin, antimicrobial peptides and enzymes, neutrophils efficiently trap pathogens like bacteria and facilitate their elimination. During this process, high concentrations of extracellular histones can be reached. Several researchers have demonstrated that the cytotoxic characteristics of these histones can trigger diseases like sepsis. Interestingly, the carbohydrate polysialic acid (polySia) can bind histones and reduce histone-mediated cytotoxicity in a chain length-dependent manner. In the present study, we examined the chain length of polySia in plasma and tested its ability to decrease the cytotoxic characteristics of extracellular histones. Remarkably, we detected polySia not only in the soluble fraction of plasma, but also on enriched extracellular vesicles (EVs). Chain length analysis revealed that polySia chains originating from human plasma can consists of more than 40 sialic acid residues and show a cytoprotective effect against extracellular histones. Intriguingly, polySia is not only present in human plasma but also in fish and other branches of vertebrates. Thus, polySia is a physiological element in plasma and may represent a natural buffer for extracellular histones.

In mammals, around the time of ovulation, the hormonal profile dynamically changes in synchrony with reproductive events occurring in the oviduct, that is, sperm arrival, fertilization, and early embryo development. Extracellular vesicles (EVs) have been recently recognized as key components of the embryonic milieu; however, composition and function of oviductal EVs during this crucial period remains to be further explored. Therefore, we initially characterized EVs from porcine oviductal fluid specifically around the critical ovulation window: that is, estrus (E), late estrus (LE, day of expected ovulation), post ovulation (PO), and additionally diestrus (D). Total EV numbers gradually rose from D to E, LE and PO (P < 0.05), which corresponded to the total EV protein amount (P < 0.05). Strikingly, the mean size of EVs in PO was significantly smaller than in E and LE groups, which also had a lesser proportion of small EVs (P < 0.05). The EV protein cargoes during the periovulatory period were further analyzed by mass spectrometry. Qualitative analysis detected 1118 common proteins, which are most enriched in the cellular component of EVs/exosomes. Hierarchical clustering indicated similar protein profile within the biological replicates, but large discrepancy among stages. Further quantitative analysis discovered 34 and 4 differentially expressed proteins in the comparison between E and PO and in the comparison between E and LE, respectively. The dynamic EV protein profile together with the quick adaption in EV size and quantity suggests that porcine oviductal EV secretion are under the hormonal influence during the estrus cycle.

The transition from farrowing crates to farrowing pens aims to improve animal welfare by enabling the expression of maternal behavioural profiles. This study examines the spontaneous farrowing process in both farrowing crates and pens for modern German Landrace (GL) and traditional German Saddleback (GS) pigs - two breeds with different breeding histories and adaptations to housing systems. The goal is to investigate whether, and how, both breeds benefit equally from farrowing pens. From the birth of the first piglet until 1 h after the last delivery (intrapartum; ip), half-hourly blood samples were collected from catheterized sows in addition to blood samples retrieved from antepartum (ap) and postpartum (pp) periods. After spontaneous, non-induced farrowing, the traditional GS breed exhibited a significantly shorter gestation length, smaller litter weight, and a lower incidence of labour dystocia compared to modern GL sows. Breed effects were observed for profiles of heart rate (ip: GL > GS), cortisol (ap: GL < GS; ip: GL < GS), adrenaline (ap: GL < GS), noradrenaline (ip: GL < GS), non-esterified fatty acids (ap: GL < GS; ip: GL < GS), glucose (ap: GL > GS), and β-hydroxybutyrate (ap: GL < GS) at distinct peripartum periods. Effects due to housing appeared for heart rate (ap: crate > pen) as well as respiratory rate (crate < pen) and adrenaline (crate > pen) at distinct time points. Taken together, breed-specific endocrine control and energy-related metabolic properties might suggest a need for tailored housing conditions during parturition for modern and traditional sows.

Ultrasound examinations offer the possibility to monitor fetal growth and estimate fetal weight, but reference data for such techniques in pigs are rare. The aim of this study was therefore to identify suitable anatomical fetal structures for monitoring physiological growth dynamics by ultrasound examinations and to estimate fetal weight using appropriate mathematical models. For this purpose, 198 fetuses of 15 primiparous Landrace sows were examined by ultrasound on days 36, 50, 64, 79 and 92 of gestation in live sows and in utero after slaughter. Biparietal distance (BPD), rostro-occipital distance (ROD), corpus vitreum diameter, heart length, abdominal circumference (AC) and transverse and sagittal abdominal diameter were determined by ultrasound in utero, and the fetuses were subsequently ex uteri determined and weighed. Reference curves for the continuous increase in fetal parameters over the pregnancy were established. Weight estimation could be performed with linear models at a known stage of pregnancy using one or a combination of parameters. Cubic equations were developed to describe the relationships between body measurements and weight over the course of gestation. BPD, ROD and AC have been shown to be the most suitable parameters for fetal weight estimation, but in live sows, only the fetal head parameters could be easily and reliably determined. These techniques could initially be of interest for research into fetal growth, but future application in veterinary practice is also conceivable.