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8
result(s) for
"WAGENAAR, J.P."
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The prevention and control of feather pecking in laying hens: identifying the underlying principles
by
DE HAAS, E.N.
,
WAGENAAR, J.P.
,
RIEDSTRA, B.J.
in
different ages
,
eating behavior
,
environmental enrichment
2013
Feather pecking (FP) in laying hens remains an important economic and welfare issue. This paper reviews the literature on causes of FP in laying hens. With the ban on conventional cages in the EU from 2012 and the expected future ban on beak trimming in many European countries, addressing this welfare issue has become more pressing than ever. The aim of this review paper is to provide a detailed overview of underlying principles of FP. FP is affected by many different factors and any approach to prevent or reduce FP in commercial flocks should acknowledge that fact and use a multifactorial approach to address this issue. Two forms of FP can be distinguished: gentle FP and severe FP. Severe FP causes the most welfare issues in commercial flocks. Severe FP is clearly related to feeding and foraging behaviour and its development seems to be enhanced in conditions where birds have difficulty in coping with environmental stressors. Stimulating feeding and foraging behaviour by providing high-fibre diets and suitable litter from an early age onwards, and controlling fear and stress levels through genetic selection, reducing maternal stress and improving the stockmanship skills of the farmer, together offer the best prospect for preventing or controlling FP.
Journal Article
The prevention and control of feather pecking: application to commercial systems
2013
Studies on the prevalence of feather pecking in different commercial laying hen
systems and its welfare and economic impacts are reviewed in the following
paper. Current methods for controlling feather pecking include beak-trimming and
alterations to light regimes, but these methods have significant disadvantages
from the perspective of bird welfare. A substantial body of research has now
identified risk factors for feather pecking during both the rearing and laying
periods. It is argued that these findings can be translated into optimised
management practices that can prevent and control feather pecking whilst
simultaneously conferring welfare benefits. The genetic basis of feather pecking
is considered, and studies that suggest group selection techniques could produce
birds with a reduced tendency to feather peck in commercial flocks are
highlighted.
Journal Article
The Equine Faecal Microbiota of Healthy Horses and Ponies in The Netherlands: Impact of Host and Environmental Factors
by
Luiken, Roosmarijn E. C.
,
Wagenaar, Jaap A.
,
Zomer, Aldert L.
in
Animals
,
Bacteroidetes
,
defecation
2021
Several studies have described the faecal microbiota of horses and the factors that influence its composition, but the variation in results is substantial. This study aimed to investigate the microbiota composition in healthy equids in The Netherlands under standard housing and management conditions and to evaluate the effect of age, gender, horse type, diet, pasture access, the season of sampling and location on it. Spontaneously produced faecal samples were collected from the stall floor of 79 healthy horses and ponies at two farms. The validity of this sampling technique was evaluated in a small pilot study including five ponies showing that the microbiota composition of faecal samples collected up to 6 h after spontaneous defaecation was similar to that of the samples collected rectally. After DNA extraction, Illumina Miseq 16S rRNA sequencing was performed to determine microbiota composition. The effect of host and environmental factors on microbiota composition were determined using several techniques (NMDS, PERMANOVA, DESeq2). Bacteroidetes was the largest phylum found in the faecal microbiota (50.1%), followed by Firmicutes (28.4%). Alpha-diversity and richness decreased significantly with increasing age. Location, age, season, horse type and pasture access had a significant effect on beta-diversity. The current study provides important baseline information on variation in faecal microbiota in healthy horses and ponies under standard housing and management conditions. These results indicate that faecal microbiota composition is affected by several horse-related and environment-related factors, and these factors should be considered in future studies of the equine faecal microbiota.
Journal Article
How do load carriage and walking speed influence trunk coordination and stride parameters?
by
Holt, K.G
,
LaFiandra, M
,
Wagenaar, R.C
in
Adaptation, Physiological - physiology
,
Adult
,
Back - physiology
2003
To determine the effects of load carriage and walking speed on stride parameters and the coordination of trunk movements, 12 subjects walked on a treadmill at a range of walking speeds (0.6–1.6
m
s
−1) with and without a backpack containing 40% of their body mass. It was hypothesized that compared to unloaded walking, load carriage decreases transverse pelvic and thoracic rotation, the mean relative phase between pelvic and thoracic rotations, and increases hip excursion. In addition, it was hypothesized that these changes would coincide with a decreased stride length and increased stride frequency. The findings supported the hypotheses. Dimensionless analyses indicated that there was a significantly larger contribution of hip excursion and smaller contribution of transverse plane pelvic rotation to increases in stride length during load carriage. In addition, there was a significant effect of load carriage on the amplitudes of transverse pelvic and thoracic rotation and the relative phase of pelvic and thoracic rotation. It was concluded that the shorter stride length and higher stride frequency observed when carrying a backpack is the result of decreased pelvic rotation. During unloaded walking, increases in pelvic rotation contribute to increases in stride length with increasing walking speed. The decreased pelvic rotation during load carriage requires an increased hip excursion to compensate. However, the increase in hip excursion is insufficient to fully compensate for the observed decrease in pelvis rotation, requiring an increase in stride frequency during load carriage to maintain a constant walking speed.
Journal Article
Longitudinal study of the short- and long-term effects of hospitalisation and oral trimethoprim-sulfadiazine administration on the equine faecal microbiome and resistome
by
Wagenaar, Jaap A.
,
Schaafstra, Femke J. W. C.
,
Rossen, John W. A.
in
Analysis
,
Animals
,
Antimicrobial agents
2023
Background
Hospitalisation and antimicrobial treatment are common in horses and significantly impact the intestinal microbiota. Antimicrobial treatment might also increase levels of resistant bacteria in faeces, which could spread to other ecological compartments, such as the environment, other animals and humans. In this study, we aimed to characterise the short- and long-term effects of transportation, hospitalisation and trimethoprim-sulfadiazine (TMS) administration on the faecal microbiota and resistome of healthy equids.
Methods
In a longitudinal experimental study design, in which the ponies served as their own control, faecal samples were collected from six healthy Welsh ponies at the farm (D0–D13-1), immediately following transportation to the hospital (D13-2), during 7 days of hospitalisation without treatment (D14–D21), during 5 days of oral TMS treatment (D22–D26) and after discharge from the hospital up to 6 months later (D27–D211). After DNA extraction, 16S rRNA gene sequencing was performed on all samples. For resistome analysis, shotgun metagenomic sequencing was performed on selected samples.
Results
Hospitalisation without antimicrobial treatment did not significantly affect microbiota composition. Oral TMS treatment reduced alpha-diversity significantly. Kiritimatiellaeota, Fibrobacteres and Verrucomicrobia significantly decreased in relative abundance, whereas Firmicutes increased. The faecal microbiota composition gradually recovered after discontinuation of TMS treatment and discharge from the hospital and, after 2 weeks, was more similar to pre-treatment composition than to composition during TMS treatment. Six months later, however, microbiota composition still differed significantly from that at the start of the study and Spirochaetes and Verrucomicrobia were less abundant. TMS administration led to a significant (up to 32-fold) and rapid increase in the relative abundance of resistance genes
sul2
,
tetQ
,
ant6-1a
, and
aph(3”)-lb
.
lnuC
significantly decreased directly after treatment. Resistance genes s
ul2
(15-fold) and
tetQ
(six-fold) remained significantly increased 6 months later.
Conclusions
Oral treatment with TMS has a rapid and long-lasting effect on faecal microbiota composition and resistome, making the equine hindgut a reservoir and potential source of resistant bacteria posing a risk to animal and human health through transmission. These findings support the judicious use of antimicrobials to minimise long-term faecal presence, excretion and the spread of antimicrobial resistance in the environment.
-NEQ1286BccpFJdhcRCuNy
Video Abstract
Journal Article
Staphylococcus aureus ST398 gene expression profiling during ex vivo colonization of porcine nasal epithelium
by
Tulinski, Pawel
,
Jonker, Martijs J
,
Breit, Timo M
in
adherence
,
Analysis
,
Animal Genetics and Genomics
2014
Background
Staphylococcus aureus
is a common human and animal opportunistic pathogen. In humans nasal carriage of
S. aureus
is a risk factor for various infections. Methicillin-resistant
S. aureus
ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig colonization by MRSA ST398 is poorly understood. Previously, we developed a nasal colonization model of porcine nasal mucosa explants to identify molecular traits involved in nasal MRSA colonization of pigs.
Results
We report the analysis of changes in the transcription of MRSA ST398 strain S0462 during colonization on the explant epithelium. Major regulated genes were encoding metabolic processes and regulation of these genes may represent metabolic adaptation to nasal mucosa explants. Colonization was not accompanied by significant changes in transcripts of the main virulence associated genes or known human colonization factors. Here, we documented regulation of two genes which have potential influence on
S. aureus
colonization; cysteine extracellular proteinase (
scpA
) and von Willebrand factor-binding protein (vWbp, encoded on SaPIbov5). Colonization with isogenic-deletion strains (Δ
vwbp
and
ΔscpA
) did not alter the
ex vivo
nasal
S. aureus
colonization compared to wild type.
Conclusions
Our results suggest that nasal colonization with MRSA ST398 is a complex event that is accompanied with changes in bacterial gene expression regulation and metabolic adaptation.
Journal Article
Modulation of force transmission to the head while carrying a backpack load at different walking speeds
by
Kubo, Masayoshi
,
Obusek, John P.
,
Holt, Kenneth G.
in
Acceleration
,
Adaptation, Physiological - physiology
,
Adult
2005
This study was designed to investigate the capability of the joints and segments to reduce transmission of forces during load carriage. Eleven subjects were required to carry a backpack loaded with 40% of their body weight and to walk at 6 speeds increasing from 0.6 to 1.6
m
s
−1 in increments of 0.2
m
s
−1, and then decreasing in the same manner. Subjects were filmed in 3-dimensions, but analysis of shock transmission ratio (TR) was limited to the sagittal plane. Shock transmission was measured as the ratio of peak vertical accelerations (ankle:head, ankle:knee, and knee:head) measured immediately following foot strike. TR for all ratios increased significantly as a function of increasing speed. TR from the ankle to the head showed no significant increase as a function of load carriage, but did increase as a function of load in transmission from knee to head. A significant interaction effect revealed that during load carriage at the higher speeds the acceleration of the ankle and knee decreased below that for the unloaded conditions. These findings suggest that the potentially injurious effects of previously observed increased ground reaction forces and increased joint stiffness while walking with loads are offset by adaptations in the gait pattern that maintain force transmission at acceptable levels. Increased variability in the acceleration of the head and in the transmission ratios suggest a potentially destabilizing effect of load carriage on the head trajectory.
Journal Article
Bacterial cell-free DNA profiling reveals co-elevation of multiple bacteria in newborn foals with suspected sepsis
2024
Sepsis is the leading cause of death in newborn foals. This study investigates whether cell-free DNA (cfDNA) sequencing can enhance bacterial pathogen detection in foals with suspected sepsis and addresses existing knowledge gaps and diagnostic challenges.
We developed a foal cfDNA sequencing for bacteria identification (cfFBI) workflow, integrating wetlab and computational protocols to detect increased bacterial cfDNA abundance in blood. Specifically, cfFBI focusses on enriching bacterial cfDNA molecules and preventing false positive bacterial identifications. cfFBI was applied to blood samples of 25 hospitalized foals categorized according to the neonatal Systemic Inflammatory Response Syndrome (nSIRS) criteria and 7 healthy foals.
cfDNA levels of potential sepsis-causing bacterial genera were elevated in all 11 nSIRS-positive foals compared to healthy foals (n=7), and in 8/11 (72.7%) when compared to both nSIRS-negative (n=4; nSIRS=0) and healthy foals, with multiple genera elevated in 5/11 (45.5%). The total cfDNA concentration, bacterial cfDNA fraction and bacterial diversity were not different between the foal groups. However, nSIRS-positive foals showed significantly different end-motifs in host chromosomal cfDNA, and a decrease in host mitochondrial cfDNA fraction.
This study is the first to demonstrate that cfDNA sequencing in blood samples from newborn foals enables detection of pathogenic bacteria and can help identify novel host-related sepsis biomarkers. The elevated presence of multiple sepsis-causing genera in nSIRS-positive foals and the difference in end-motif, suggests that multibacterial elevation may be more common than previously thought. These findings indicate that cfDNA sequencing holds promise as a future diagnostic tool for identifying sepsis in newborn foals.