Geert Opsomer

Geert Opsomer
Ghent University | UGhent · Department of Obstetrics, Reproduction and Herd Health

DVM, PhD, Msc, Dipl ECAR, Dipl ECBHM

About

407
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Publications

Publications (407)
Article
Full-text available
Cumulus expansion is an important indicator of oocyte maturation and has been suggested to be indicative of greater oocyte developmental capacity. Although multiple methods have been described to assess cumulus expansion, none of them is considered a gold standard. Additionally, these methods are subjective and time-consuming. In this manuscript, t...
Article
Full-text available
The debate about the pioneer colonization of the fetus is still open, being the ‘in utero colonization’ hypothesis versus the ‘sterile womb paradigm’ the two opposing sides. The seed in this field of research sprouted in human medicine in the last decade and became a central topic in other mammals as well. We aimed to review the literature on bacte...
Article
The effect of supplementing rumen undegradable protein (RUP) in the dry period on the colostrum immunoglobulin G (IgG) concentration and microbial composition was evaluated. Furthermore, the effect of maternal RUP supplementation on the calf's serum IgG absorption, birthweight, and growth rate was analyzed. Prepartum RUP supply increased colostrum...
Article
The transition period is one of the most challenging periods in the lactation cycle of high-yielding dairy cows. It is commonly known to be associated with diminished animal welfare and economic performance of dairy farms. The development of data-driven health monitoring tools based on on-farm available milk yield dev has shown potential in identif...
Poster
Full-text available
Lameness perception by untrained observers. Huge thanks to Dr. Nick Bell and Peacock Industries for sharing the mobility scoring clips and gold standard scores.
Conference Paper
Full-text available
Objectives Preventive hoof trimming (HT) is essential to prevent lameness in high producing dairy cattle, yet little is known about how it's performed by hoof trimmers. The goal of this survey was to provide an overview of the current preventive hoof trimming techniques internationally applied in dairy cattle. Emphasis was put on the order in which...
Article
Full-text available
This study is the first to investigate the transcriptomic changes occurring in severe udder cleft dermatitis lesions (UCD) in Holstein-Friesian cows. An examination of the gene expression levels in natural UCD lesions and healthy udder skin through RNA Seq-Technology provided a deeper insight into the inflammatory pathways associated with this dise...
Article
The anogenital distance (AGD) is considered a marker for prenatal androgen exposure and fertility in multiple species including humans. In dairy cattle, it is described as the length between the center of the anus and the clitoral base (AGDc). However, in other species, the distance from the center of the anus to the dorsal commissure of the vulva...
Article
This study aimed to investigate the presence of Chlamydia spp. and Parachlamydia acanthamoebae in bovine placental tissue originating from abortion and non-abortion cases in Belgium. Placentas of 164 late term bovine abortions (last trimester of gestation) and 41 non-abortion (collected after calving) cases were analyzed by PCR for Chlamydia spp.,...
Article
Full-text available
In brief Clinical and subclinical endometritis are different manifestations of reproductive tract inflammatory disease in dairy cows. This review addresses the genesis of clinical and subclinical endometritis considering metabolic stress, innate immune dysfunction, and shifts in the composition of the uterine microbiota in the postpartum period. A...
Article
Full-text available
Application: Ex-vivo validation of a semi-automated device on slaughterhouse-derived uteri for the collection of cytological samples from the endometrium for the diagnosis of subclinical endometritis (SE) in dairy cows by naive operators. Introduction: Subclinical endometritis is one of the most frequent diseases affecting the reproductive tract of...
Presentation
Application: To identify the microbial composition of samples collected from postpartum uterus of dairy cows diagnosed with clinical (CE) or subclinical endometritis (SCE). Introduction: Clinical endometritis is characterized by uterine bacterial dysbiosis and inflammatory changes in endometrium. 16S rRNA sequencing is used for culture-independent...
Article
Background: Anaplasma phagocytophilum is a tick-borne zoonotic bacterium that is the aetiologic pathogen of tick-borne fever (TBF) in ruminants. In clinical bovine cases of TBF, abortion and stillbirth may be observed. However, in this regard, the pathophysiology of TBF has not yet been completely elucidated, and no clear guidelines to diagnose A....
Article
Full-text available
While human in vitro embryo production is generally performed individually, animal models have shown that culturing embryos in groups improves blastocyst yield and quality. Para-crine embryotrophins could be responsible for this improved embryo development, but their identity remains largely unknown. We hypothesize that supplementation of embryotro...
Article
Full-text available
Telomere length is associated with longevity and survival in multiple species. In human population-based studies, multiple prenatal factors have been described to be associated with a newborn's telomere length. In the present study, we measured relative leukocyte telomere length in 210 Holstein Friesian heifers, within the first ten days of life. T...
Article
We aimed to compare the viability of circulating polymorphonuclear leukocyte (cPMN) and endometrial PMN (ePMN) and their function dynamics in postpartum dairy cows with subclinical (SCE) or clinical endometritis (CE). To do so, blood samples from 38 Holstein cows were collected at -7, 9, 21, and 36 d relative to calving, and endometrial cytology sa...
Preprint
Full-text available
Cumulus expansion is an important indicator of oocyte maturation, often correlated with greater oocyte developmental capacity. Although multiple methods have been described to assess cumulus expansion, none of them is considered a gold standard. Additionally, these methods are subjective and time-consuming. Here, the reliability of three cumulus ex...
Article
Isoflavones represent a class of phytoestrogens present in plants. In dairy cows, dietary isoflavones have been shown to negatively affect reproductive performance. To the best of our knowledge, no studies have yet been conducted to determine if calves are pre- or neonatally confronted with isoflavones and their metabolites. In the present study, w...
Article
Recent studies have suggested that bacteria associated with the female reproductive tract - the uterine microbiota - may be important for reproductive health and pregnancy success. Therefore, uterine microbiome research gained much interest in the last few years. However, it is challenging to study late postpartum uterine samples, since they hold a...
Article
Full-text available
Dairy cows diagnosed with metritis may experience a greater degree of oxidative stress (OS) and a deficit in the antioxidative capacity compared to healthy cows. We aimed to assess circulating OS markers and endometrial cell mitochondrial function, intracellular reactive oxygen species (ROS) production, and mean endometrial nuclear cell area in pos...
Article
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The transition between two lactations remains one of the most critical periods during the productive life of dairy cows. In this study, we aimed to develop a model that predicts the milk yield of dairy cows from test day milk yield data collected in the previous lactation. In the past, data routinely collected in the context of herd improvement pro...
Poster
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Introduction: There is a state of immune dysfunction in the peripartum of dairy cows, which may lead them to the development of infectious diseases. White blood cells, specifically polymorphonuclear neutrophils (PMN), play a vital role in the innate immune response in the early postpartum. In dairy research, in vitro assessment of innate immune fun...
Article
Full-text available
Objectives of the present study were to get a deeper insight into the course of the inflammatory pathways of digital dermatitis lesions in dairy cattle by investigating the gene expression patterns throughout the different clinical stages (M0 to M4.1) of the disease. Normal skin samples (M0) were used as a reference for comparing the gene expressio...
Article
Full-text available
For centuries, multicellular organisms have lived in symbiosis with microorganisms. The interaction with microorganisms has been shown to be very beneficial for humans and animals. During a natural birth, the initial inoculation with bacteria occurs when the neonate passes through the birth canal. Colostrum and milk intake are associated with the a...
Article
Neospora caninum is a protozoan parasite that causes abortion, perinatal mortality, and subfertility in cattle worldwide. Despite the presence of the DNA of the parasite in semen of infected bulls, the effect on semen quality has not been extensively studied. This study aimed to investigate the effect of a natural Neospora caninum infection on fres...
Poster
Full-text available
BACKGROUND-AIM Reactive oxygen species (ROS) production is a physiological, dynamic process in all cells. However, ROS production is exacerbated during in vitro conditions mainly due to its high oxygen tension. This study aimed to evaluate the effect of lycopene supplementation into a serum-free culture medium on blastocyst development and quality....
Poster
Full-text available
BACKGROUND-AIM: Subclinical endometritis (SCE) is the most prevalent uterine disease in dairy cows. The assessment of polymorphonuclear leukocyte (PMN) proportions (%) of endometrial samples is the hallmark for SCE diagnosis. However, observing cytology slides under a light microscope is a time-consuming and subjective procedure. Yet, a non-biase...
Article
Full-text available
Selenium is commonly used as antioxidant in a serum-free culture medium setting. However, lycopene has emerged as a potent antioxidant being twice as efficient as β-carotene and ten times as efficient as α-tocopherol with beneficial effects when supplemented in a serum-free maturation medium. Here we aimed to evaluate the effect of lycopene supplem...
Article
Full-text available
After parturition, dairy cows undergo a plethora of metabolic, inflammatory, and immunologic changes to adapt to the onset of lactation. These changes are mainly due to the homeorhetic shift to support milk production when nutrient demand exceeds dietary intake, resulting in a state of negative energy balance. Negative energy balance in postpartum...
Article
In cattle, hydrops amnion is a rare pathological condition. In the present study, we report such a case in a Belgian blue cow suffering from prolonged gestation. A presumptive diagnosis was based on clinical examination, including transrectal ultrasonography. Management included inducing parturition with dinoprost and dexamethasone, where 36 hours...
Article
Full-text available
We aimed to research the neutrophil extracellular traps (NETs) and reactive oxygen species (ROS) formation capacity of polymorphonuclear cells (PMN) during different lactational stages of Holstein cows. We also aimed to validate a model which could mimic infection and inflammation in vitro by adding increasing concentrations of lipopolysaccharide (...
Article
Breed type and environmental factors such as breeding season may have a significant impact on neonatal morphometrics. We followed a total of 236 elective cesarean sections in Belgian Blue (BB) cows, from which neonatal calves were morphometrically assessed (in cm) within the first 72 h of delivery using a strictly standardized protocol. The effect...
Article
Full-text available
Background Previous studies have identified many immune pathways which are consistently altered in humans and model organisms as they age. Dairy cows are often culled at quite young ages due to an inability to cope adequately with metabolic and infectious diseases, resulting in reduced milk production and infertility. Improved longevity is therefor...
Article
The aim of the present study was to assess the counts, viability, and functionality of circulating and endometrial polymorphonuclear leukocytes (PMN) isolated from fourteen clinically and metabolically healthy multiparous dairy cows in the peripartum period. For this, blood samples were collected at −5, +9, +21 and + 37 days (d) relative to calving...
Article
Nutritional modifications can potentially impact the reproductive performance and ultimately the economic results of dairy herds. The objectives were to investigate the effects of feeding a high starch (HS) diet and body condition score (BCS) at calving on reproductive responses and uterine health in Holstein dairy cows. One hundred seventy-four mu...
Preprint
Full-text available
Breed type and environmental factors such as breeding season may have a significant impact on neonatal weight loss calf size. We followed a total of 236 elective cesarean sections in Belgian Blue (BB) cattle, in which neonatal calves were morphometrically measured (in cm) in the first 72 hours after delivery of the child using a strictly standardiz...
Article
We investigated the effect of the antioxidant lycopene supplemented into the in vitro maturation medium (TCM-199 with 20 ng/mL epidermal growth factor and 50 mg/mL gentamycin) in a heat shock (HS) model to mimic in vivo heat stress conditions. Bovine cumulus-oocyte complexes were supplemented with 0.2 μM lycopene (or not supplemented; control) unde...
Article
Abortion and perinatal mortality, leading causes of economic loss in cattle industry, are the consequence of both non-infectious and a wide range of infectious causes. However, the relative contribution of pathogens to bovine abortion and perinatal mortality is poorly documented, since available studies involved only a limited number of pathogens....
Article
Neutrophils largely contribute to the first line of defense against the invasion of pathogens. They kill pathogens basically by the following mechanisms: phagocytosis and proteolytic degradation, the release of enzymes with bactericidal activities, and the production of fibers to entrap pathogens, also known as neutrophil extracellular traps (NETs)...
Article
Longevity is an important trait both from an economic and social perspective. Modern dairy cows are criticized for their short productive lifespan: only a minority of animals survives to a fourth lactation, implying that most cows are culled before reaching their maximal potential. In contrast, the population of 100 tonne cows (HT), reaching the th...
Article
Full-text available
Bovine mastitis, an inflammatory disease of the mammary gland, is classified as subclinical or clinical. Circulating neutrophils are recruited to the udder to combat infection. We compared the transcriptomic profiles in circulating leukocytes between healthy cows and those with naturally occurring subclinical or clinical mastitis. Holstein Friesian...
Article
Full-text available
The development of a healthy intestinal immune system requires early microbial exposure. However, it remains unclear whether microbial exposure already begins at the prenatal stage. Analysis of such low microbial biomass environments are challenging due to contamination issues. The aims of the current study were to assess the bacterial load and cha...
Article
Overconditioning is a risk factor for upregulated pre- and postpartum fat mobilization. Therefore, we hypothesized that overconditioning at the end of pregnancy leads to the accumulation of lipids in the liver and modifications of the hepatic gene expression pattern. The aim of this study was to evaluate the effect of normal- versus overconditionin...
Article
Full-text available
Postpartum dairy cows experience impaired peripheral polymorphonuclear leukocyte (PMN) functionality, which has been associated with reproductive tract inflammatory diseases. However, it has not been elucidated yet whether endometrial PMN functionality is (equally) impaired. We developed a method for endometrial PMN isolation and flow cytometric as...
Article
The microbiome from the reproductive tract is being investigated for its putative effect on fertility, embryo development, and health status of the human or animal host postpartum. Besides the presence of a vaginal microbiome, recent studies have claimed the existence and putative role of the uterine microbiome. Yet, the extremely low bacterial num...
Article
Identification of factors associated with the quality and quantity of colostrum production has always been a major challenge in cattle industry. In purebred double-muscled Belgian Blue (BB) cows, parturition is mainly performed by elective caesarean section (CS; >90%). However, the CS itself may influence colostrum production characteristics. The p...
Article
The quality of an oocyte is often represented by its morphological characteristics. Stringent selection of bovine cumulus–oocyte complexes (COCs) for invitro embryo production (IVP) is regularly based on parameters such as colour and granulation of the ooplasm, density of the surrounding cumulus cells, brightness of the zona pellucida, among other...
Preprint
Full-text available
The fetal gut microbiome is being investigated for its putative effect on fetal development and maturation of the immune system. In this environment the low amounts of bacteria and bacterial DNA makes them highly challenging to accurately isolate and identify, and sensitive to contamination issues. The aims of the current study were to assess the b...
Article
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We hypothesized that a single dose of PGF 2α belatedly injected on day 8 after GnRH-1 in cows receiving a 7-day Ovsynch-56 protocol (GnRH-7 days-PGF 2α-56h-GnRH-16h-timed AI) will increase the proportion of cows with complete luteolysis. At day 35±3 postpartum, 70 lactating Holstein cows from one herd were scored for body condition and pre-synchron...
Article
Full-text available
All modern, high-yielding dairy cows experience a certain degree of reduced insulin sensitivity, negative energy balance, and systemic inflammation during the transition period. Maladaptation to these changes may result in excessive fat mobilization, dysregulation of inflammation, immunosuppression, and, ultimately, metabolic or infectious disease...
Article
The increased exportation of semen and embryos of double-muscled beef breeds to tropical and developing countries makes it important to investigate the reproductive capacity of these breeds in adapting to tropical conditions. The aim of this study was to evaluate the quality of Belgian Blue semen collected after there is heat-stress (HS; as a mimic...
Article
Full-text available
The aim of this study was to detect the genomic region or regions associated with metabolic clusters in early-lactation Holstein cows. This study was carried out in 2 experiments. In experiment I, which was carried out on 105 multiparous Holstein cows, animals were classified through k-means clustering on log-transformed and standardized concentrat...
Article
Nowadays, several developing countries have started to breed double-muscled cattle to their autochthonous cattle to improve meat production. However, the developmental competence of the resultant crossbreeding embryos is unknown. The objective of this study was to evaluate the effect of crossbreeding double-muscled (Belgian Blue; BB) semen with bee...
Article
Full-text available
De keizersnede is een routine-ingreep voor dierenartsen in de Vlaamse rundveepraktijk. Alhoewel de ingreep wordt aangeleerd volgens een standaardprotocol, blijkt uit eerder onderzoek dat het antibioticumgebruik bij deze indicatie sterk varieert tussen dierenartsen. In deze studie werd door middel van een vragenlijst getracht een beeld te schetsen v...
Article
Full-text available
Improving reproductive performance is one of the most important factors affecting the profitability of dairy herds. This study investigated the effect of feeding a high starch ( HS ) diet and body condition score ( BCS ) at calving on blood metabolites, fertility and ovarian function and milk production in Holstein dairy cows. One hundred seventy-f...
Article
Full-text available
Simple Summary: Reproductive performance is an important factor, which determines productive life and drives culling decisions in dairy herds. There are strong motives for including reproductive performance in genetic selection programs of dairy cows; however, low heritability estimates reported for reproductive performance measures limit the genet...
Article
Full-text available
The aim of the present study was to identify genomic region(s) associated with the length of the calving interval in primiparous (n = 6866) and multiparous (n = 5071) Holstein cows. The single nucleotide polymorphism (SNP) solutions were estimated using a weighted single-step genomic best linear unbiased prediction (WssGBLUP) approach and imputed h...
Article
Full-text available
Improving nitrogen use efficiency (NUE) at both the individual cow and the herd level has become a key target in dairy production systems, for both environmental and economic reasons. Cost-effective and large-scale phenotyping methods are required to improve NUE through genetic selection and by feeding and management strategies. The aim of this stu...
Article
The cesarean section (SC) is an example of a routine surgery frequently conducted by Flemish veterinarians in bovine practice. Although the operation technique is taught according to a standard protocol, it has been shown in previous studies that antimicrobial usage during this procedure is highly variable. In the present study, a questionnaire was...
Article
Full-text available
Bovine herpesvirus 4 (BoHV-4) is a gammaherpesvirus that is widespread in cattle. However, only a few studies about the pathogenesis of BoHV-4 primary infection have been reported. In the present study, ex vivo models with bovine nasal and tracheal mucosa explants were used to study the cellular BoHV-4-host interactions. Infection was observed in n...
Article
Full-text available
Both blood- and milk-based biomarkers have been analysed for decades in research settings, although often only in one herd, and without focus on the variation in the biomarkers that are specifically related to herd or diet. Biomarkers can be used to detect physiological imbalance and disease risk and may have a role in precision livestock farming (...
Article
Full-text available
The aim of this study was to identify genomic regions associated with 305‐day milk yield and lactation curve parameters on primiparous (n = 9,910) and multiparous (n = 11,158) Holstein cows. The SNP solutions were estimated using a weighted single‐step genomic BLUP approach and imputed high‐density panel (777k) genotypes. The proportion of genetic...
Article
Full-text available
Colostrum is the first milk produced by a cow after she gives birth. Compared with mature milk, it has a high concentration of immunoglobulin G. Calves are born without circulating antibodies, thus ingestion of colostrum is necessary to protect the calf against pathogens in the first challenging weeks of life. In addition to the life-saving supply...
Article
The aim of this study was to describe metabolism of early-lactation dairy cows by clustering cows based on glucose, insulin-like growth factor I (IGF-I), free fatty acid, and β-hydroxybutyrate (BHB) using the k-means method. Predictive models for metabolic clusters were created and validated using 3 sets of milk biomarkers (milk metabolites and enz...
Article
The aim of this study was to describe metabolism of early-lactation dairy cows by clustering cows based on glucose, insulin-like growth factor I (IGF-I), free fatty acid, and β-hydroxybutyrate (BHB) using the k-means method. Predictive models for metabolic clusters were created and validated using 3 sets of milk biomarkers (milk metabolites and enz...
Article
In the past, bovine herpesvirus 4 (BoHV-4) has been suggested to be associated with metritis and endometritis. However, not many field studies investigated the association between BoHV-4 and subclinical endometritis (SCE). In the present study, the association between the intrauterine presence of BoHV-4 and SCE diagnosed during artificial inseminat...
Article
This study aimed to evaluate the association between individual and multiple metabolic diseases (MD and MD+) diagnosed during the transition period (±3 wk relative to calving) and the probability of pregnancy until 210 days in milk (DIM) in Holstein-Friesian dairy cows. Disease and reproductive data from a dairy herd with 1946 calvings (n=542 primi...