Farrowing accommodation for organic pigs

Newborn piglets in organic farrowing pens have a lower survival rate than in conventional farrowing pens. This difference is mainly caused by housing the sow loose compared to crated and by climatic effects of the outdoor temperature. Organic lactating sows should have at least 7.5 m² indoor area with straw and a 2.5 m² outdoor run. The aim of the project was to increase piglet survival in order to improve animal welfare as well as the profitability of organic farms. In the experiment we compared survival and behaviour in 3 pen types: type 1 with outdoor run, type 2 with an indoor run and a higher proportion of solid floor and type 3 without run. Data was analysed with Analysis of Variance using parity and liveborn piglets as covariables. Results of 131 litters in total showed 9.6a, 10.8b and 9.4a (p=0.05) weaned piglets per litter for pen type 1, 2 and 3. Fouling scores indicating dunging behaviour in the indoor lying area showed 13a, 21b and 19b (p=0.04) for pen types 1, 2 and 3. We found a tendency that litters with high survival rates used the separate piglet nest sooner for lying than the litters with low survival rates. Climatic conditions seemed to be crucial for the vitality and survival of the newborn piglets. The better climatic conditions combined with the higher proportion of solid floor resulted in a higher survival rate of the piglets. These results are currently used in a second experiment focussing on extra heating around farrowing and solid floor proportion in a new farrowing accommodation

Effect of cleaning /disinfection strategies on helminth infections in finishing pigs

Ascaris suum is the most prevalent helminth on organic pig farms (Carstensen et al., 2002) and is transmitted mainly via the faeces. The use of anthelmintics does not fit in the organic principles and preventive measures are promoted. This project focused on assessing the efficacy of a cleaning protocol for the dunging area of pens on Ascaris s. transmission to pigs. In 4 batches with 8 identical pens for 15 pigs each (n=480 pigs) 6 pigs per pen were orally infected with Ascaris s. The other pigs can be earliest infected at 10 weeks and half of the pens were thoroughly cleaned at that time. Affected livers and egg counts in the manure had to show if this cleaning protocol keeps the non infected animals free of Ascaris s. The results show no effect of the cleaning protocol on the non infected pigs. These pigs had 57% damaged livers in both treatment and 50% had positive egg counts in the manure. The conclusion is that pen hygiene does not contribute to a reduction of Ascaris s. infections

Effect of rooting area and drinker in the outdoor run on behaviour and Ascaris infection of organic pigs

Hygiene is often a problem on the outdoor runs of growing organic pigs. Manure and urine are mainly excreted outside, but spread all over the run. Reduc-ing the dirty surface may improve well being, reduce ammonia emission, improve hygiene and reduce labour and parasite infections. The presence of a rooting area and of a drinker on the outdoor run were tested in a 2x2 factorial design. The pens with the rooting areas had a higher number of pigs on the outdoor run than the pens without a rooting area (1.6 vs 1.2 pigs). This was caused by more pigs in area 2 and 3. At higher temperatures there were more pigs outside, except in the root-ing area: this was popular at all temperatures. A rooting area resulted in a cleaner outdoor area, however in some cases the root-ing area became a dunging area. An extra outdoor drinker leads to a cleaner area around the drinker, but to a dirtier indoor area. No difference in Ascaris infection was found between the four treatment combinations

Extra snijmais goed voor welzijn varkens

Vleesvarkens hebben graag een emmer snijmais. Dat blijkt uit praktijkonderzoek op Varkens Innovatie Centrum Sterksel, onderdeel van Wageningen UR. In vergelijking met stro heeft snijmais meer voederwaarde en het leidt minder snel tot verstoppingen in de mestput

Preliminary experiences on organic farrowing pen size

Background ● Newborn piglet mortality in organic herds is often higher than in conventional herds. The legal minimum of 7.5m² indoor pen surface is considered a real minimum and separation of functional areas is better with 8m² or more. ● In cooperation with organic pig farmers we started a comparison of standard and large farrowing pen

Functional investigation of two simultaneous or separately segregating DSP variants within a single family support the theory of a dose-dependent disease severity

Desmoplakin (DP) is an important component of desmosomes, essential in cell-cell connecting structures in stress-bearing tissues. Over many hundreds of pathogenic variants in DSP have been associated with different cutaneous and cardiac phenotypes or a combination, known as a cardiocutaneous syndrome. Of less than 5% of the reported DSP variants, the effect on the protein has been investigated. Here, we describe and have performed RNA, protein and tissue analysis in a large family where DSPc.273+5G>A/c.6687delA segregated with palmoplantar keratoderma (PPK), woolly hair and lethal cardiomyopathy, while DSPWT/c.6687delA segregated with PPK and milder cardiomyopathy. hiPSC-derived cardiomyocytes and primary keratinocytes from carriers were obtained for analysis. Unlike the previously reported nonsense variants in the last exon of DSP that bypassed the nonsense-mediated mRNA surveillance system leading to protein truncation, variant c.6687delA was shown to cause loss of protein expression. Patients carrying both variants and having a considerably more severe phenotype were shown to have 70% DP protein reduction, while patients carrying only c.6687delA had 50% protein reduction and a milder phenotype. Analysis of RNA from patient cells did not show any splicing effect of the c.273+5G>A variant. However, a minigene splicing assay clearly showed alternative spliced transcripts originating from this variant. This study shows the importance of RNA and protein analyses to pinpoint the exact effect of DSP variants instead of solely relying on predictions. In addition, the particular pattern of inheritance, with simultaneous or separately segregating DSP variants within the same family, strongly supports the theory of a dose-dependent disease severity

Gain-of-function mutation in ubiquitin ligase KLHL24 causes desmin degradation and dilatation in hiPSC-derived engineered heart tissues

The start codon c.1A>G mutation in KLHL24, encoding ubiquitin ligase KLHL24, results in the loss of 28 N-terminal amino acids (KLHL24-ΔN28) by skipping the initial start codon. In skin, KLHL24-ΔN28 leads to gain of function, excessively targeting intermediate filament keratin-14 for proteasomal degradation and ultimately causing epidermolysis bullosa simplex (EBS). The majority of patients with EBS are also diagnosed with dilated cardiomyopathy (DCM), but the pathological mechanism in the heart is unknown. As desmin is the cardiac homolog of keratin-14, we hypothesized that KLHL24-ΔN28 leads to excessive degradation of desmin, resulting in DCM. Dynamically loaded engineered heart tissues (dyn-EHTs) were generated from human-induced pluripotent stem cell–derived (hiPSC-derived) cardiomyocytes from 2 patients and 3 nonfamilial controls. Ten-fold lower desmin protein levels were observed in patient-derived dyn-EHTs, in line with diminished desmin levels detected in patients’ explanted heart. This was accompanied by tissue dilatation, impaired mitochondrial function, decreased force values, and increased cardiomyocyte stress. HEK293 transfection studies confirmed KLHL24-mediated desmin degradation. KLHL24 RNA interference or direct desmin overexpression recovered desmin protein levels, restoring morphology and function in patient-derived dyn-EHTs. To conclude, presence of KLHL24-ΔN28 in cardiomyocytes leads to excessive degradation of desmin, affecting tissue morphology and function, which can be prevented by restoring desmin protein levels

Disruption of tuftelin 1, a desmosome associated protein, causes skin fragility, woolly hair and palmoplantar keratoderma

Desmosomes are dynamic complex protein structures involved in cellular adhesion. Disruption of these structures by loss of function variants in desmosomal genes lead to a variety of skin and heart related phenotypes. Here, we report tuftelin 1 as a desmosome-associated protein, implicated in epidermal integrity. In two siblings with mild skin fragility, woolly hair and mild palmoplantar keratoderma, but without a cardiac phenotype, we identified a homozygous splice site variant in the TUFT1 gene, leading to aberrant mRNA splicing and loss of tuftelin 1 protein. Patients' skin and keratinocytes showed acantholysis, perinuclear retraction of intermediate filaments, and reduced mechanical stress resistance. Immunolabeling and transfection studies showed that tuftelin 1 is positioned within the desmosome and its location dependent on the presence of the desmoplakin carboxy-terminal tail. A Tuft1 knock-out mouse model mimicked the patients' phenotypes. Altogether, this study reveals tuftelin 1 as a desmosome-associated protein, whose absence causes skin fragility, woolly hair and palmoplantar keratoderma.</p

Disruption of tuftelin 1, a desmosome associated protein, causes skin fragility, woolly hair and palmoplantar keratoderma

Desmosomes are dynamic complex protein structures involved in cellular adhesion. Disruption of these structures by loss of function variants in desmosomal genes lead to a variety of skin and heart related phenotypes. Here, we report tuftelin 1 as a desmosome-associated protein, implicated in epidermal integrity. In two siblings with mild skin fragility, woolly hair and mild palmoplantar keratoderma, but without a cardiac phenotype, we identified a homozygous splice site variant in the TUFT1 gene, leading to aberrant mRNA splicing and loss of tuftelin 1 protein. Patients' skin and keratinocytes showed acantholysis, perinuclear retraction of intermediate filaments, and reduced mechanical stress resistance. Immunolabeling and transfection studies showed that tuftelin 1 is positioned within the desmosome and its location dependent on the presence of the desmoplakin carboxy-terminal tail. A Tuft1 knock-out mouse model mimicked the patients' phenotypes. Altogether, this study reveals tuftelin 1 as a desmosome-associated protein, whose absence causes skin fragility, woolly hair and palmoplantar keratoderma