M. Articularis Coxae—a Possible Receptor Organ

The purpose of the study was to analyse the morphology of the equine m. articularis coxae with reference to its function during locomotion. The muscle was a constant finding in 50 horses of verying age nad sex. Different horses were selected for dissection of the muscle with its vessels and nerves, determining of length at different angles of the hip joint and weight. The muscle was shortest at maximal fexion, and the length incereased rapidly until a hip joint angle of 110°. Between 11° and maximal extension the increase in length was moderate. The mean weight of muscle was 2.7 g. Histological specimens were serially sectioned and the frequency of muscle spindles was recorded. The spindle density varied from 12 to 42 per gramme of muscel, with a mean of 26, and a mean length of the muscle spindles of 4.7 mm.
Myectomy was performed uni- or bilaterally on 5 horses to evaluate the influenceon the locomotion with no significant manges observed.
Considering the position, size, innervation and multitude of muscle spindles of the m. articularis coxae it is suggested that the muscle primarily has a receptor function inreporting on the torsion or "wrinkling" of the hip joint. The absence of manges in loconiotion of the myectomised horses indicates that the missing function of the muscle is taken over by other muscles.     

Influence of cereal non-starch polysaccharides on ileo-caecal and rectal microbial populations in growing pigs

The effect of cereal non-starch polysaccharides (NSP) on the gut microbial populations was studied in 5 growing pigs between 39-116 kg body weight according to a Latin square design. The diets were composed to contain different NSP levels. The control diet had a normal NSP content (139 g/kg dry matter (DM)), 2 diets had a low total amount of NSP (95 and 107 g/kg DM) and 2 diets had a high amount of total NSP (191 and 199 g/kg DM). Furthermore, one of the diets within each category had a content of insoluble NSP similar to the control diet and one had a high content of insoluble NSP. Samples were collected from the ileum, via intestinal post valve T-caecum (PVTC) cannulas surgically inserted at the ileo-caecal ostium, and from the rectum. The total microbial flora of the ileal samples were analysed for by defining base pair length with terminal restriction fraction length polymorphism (T-RFLP). The microbial diversity of the coliform flora of the ileal and rectal samples were defined by biochemical fingerprinting. It was observed that many terminal restriction fragments (TRFs) disappeared when new diets were introduced and that some characteristic TRFs were found in the high and low NSP diets, respectively. Both the total gut microflora and the coliform flora were influenced by the dietary NSP content.     

Moderate nitrogen retention in temperate heath ecosystem after elevated CO2, drought and warming through 7 years

Nitrogen (N) dynamic is one of the main controlling factors of responses to climate change in N-limited terrestrial ecosystems, which rely on nutrient recycling and retention. In this study we investigate the N partitioning in ecosystem compartments of a grassland heath, and the impact of multiple climate change factors on long-term N retention after ¹⁵N pulse labelling. The impacts of elevated carbon dioxide (eCO₂), warming and drought and the treatments in combination on ecosystem N retention were investigated in a field scale manipulation experiment. A 6-year time-course was assessed by pulse-labelling with the stable N isotope ¹⁵N and by sampling after 1 day, 1 year and 6 years. After 6 years we observed that the total ecosystem retained 42% of the amended ¹⁵N across treatments (recovery of the amended ¹⁵N in the pool). The fate of the applied ¹⁵N was mainly stabilization in soil, with 36% ¹⁵N recovery in soil, while the plant compartment and microbial biomass each retained only 1%–2% of the added ¹⁵N. This suggests a moderate retention of N, for all treatments, as compared to similar long-term studies of forest ecosystems. A decreased ammonium and vegetation N pool combined with higher ¹⁵N retention in the soil under eCO₂ treatments suggests that eCO₂ promoted processes that immobilize N in soil, while warming counteracted this when combined with eCO₂. Drought treatments contrastingly increased the vegetation N pool. We conclude that as the organic soil layer has the main capacity for N storage in a temperate heathland-grassland, it is important for buffering nutrient availability and maintaining a resilient ecosystem. However, the full treatment combination of drought, warming and eCO₂ did not differ in ¹⁵N recovery from the control, suggesting unchanged long-term consequences of climate change on retention of pulse added N in this ecosystem.     

Population structure and linkage disequilibrium in diploid and tetraploid potato revealed by genome‐wide high‐density genotyping using the SolCAP SNP array

Genome‐wide association (GWA) mapping in potato requires high‐density genotyping. With the Illumina SolCAP potato single‐nucleotide polymorphism (SNP) array, a first tool for GWA mapping in potato became available. Thirty‐six tetraploid varieties and eight diploid breeding clones were genotyped for 8303 SNPs using this array. The objectives of our study were to examine in this set of germplasm: (i) the degree of polymorphism of the SolCAP SNPs in European germplasm, (ii) the population structure, (iii) temporal trends of genetic diversity and (iv) the genome‐wide extent of linkage disequilibrium (LD). Three‐quarters of the SNPs were polymorphic. In the principal coordinate analysis, a clear separation of tetraploid from diploid genotypes was observed, whereas no distinct subgroups among the tetraploid varieties were detected. The nonlinear trendline of the LD measure vs. the physical map distance decayed within 275 bp to an value of 0.10, indicating that theoretically, about 3 million equally distributed SNPs are required for GWA mapping in this diverse set of germplasm. As the LD decay changes with the population selected for GWA mapping, the number of required markers might be different in other germplasm.     

Abrasions and lameness in piglets born in different farrowing systems with different types of floor

Background

The quality of the floor is essential to the welfare of piglets as abrasions often are recorded in newborn piglets, and such lesions may lead to lameness. Apart from animal suffering, lameness contributes to losses in form of dead piglets, decreased growth, and increased use of antibiotics and manual labour.

Methods

In a herd with three different farrowing systems, 37 litters (390 piglets) were studied until the age of 3 weeks with respect to presence of skin wounds and abrasions. Lameness was registered until the age of 7 weeks. Eight lame piglets were sacrificed before medical treatment and subjected to necropsy including histopathological and microbiological examinations. Isolates of streptococci, staphylococci and E. coli were tested with respect to antimicrobial resistance. Mastitis was observed in ten sows.

Results

The most severe abrasions at carpus and soles were seen in the system with a new solid concrete floor with a slatted floor over the dunging area. The lowest magnitude was observed in the deep litter system with peat. Sole bruising was more common in the systems with concrete floor compared to the deep litter system with peat, and the differce in prevalence was significant at all examination days. The lesions decreased with time and about 75% of the treatments for lameness were performed during the first three weeks of life. The overall prevalence of lameness was highest in the system with new solid concrete floor with a slatted floor over the dunging area (9.4%) followed by the old solid concrete floor (7.5%). A lower (p < 0.05) prevalence was seen in the deep litters system with peat (3.3%). No significant relationship between mastitis and abrasions or lameness in the offspring was observed.

Conclusion

There were large differences in the prevalence of abrasions and lameness between the floor types. The deep litter system with peat provided a soft and good floor for piglets. The overall prevalence of lameness was only diagnosed in every fourth litter in that system compared to in every second litter in the systems with concrete floor. In contrast, the incidence of mastitis in the sows during the first week after farrowing was higher than in the systems with concrete floor.     

Effect of supplemented fungal phytase on performance and phosphorus availability by phosphorus-depleted juvenile rainbow trout (Oncorhynchus mykiss), and on the magnitude and composition of phosphorus waste output

The effect of a supplemental fungal phytase on performance and phosphorus availability by juvenile rainbow trout fed diets with a high inclusion of plant based protein and on the magnitude and composition of the waste phosphorus production was tested in a 2 × 3 factorial design at a temperature of 11 °C. Two factors comprised of two dietary fungal phytase levels (0 or 1400 U kg^? 1 feed^? 1), and three dietary total phosphorus levels (0.89, 0.97 or 1.12%). All fish were acclimated to the lowest total phosphorus diet for 16 days, which included 0.29% phytate-phosphorus and no supplemental fungal phytase, to ensure that they were depleted of phosphorus prior to the feeding trial.Growth and feed conversion ratios were not significantly affected by the increasing dietary phosphorus level or supplemental fungal phytase. Phosphorus availability increased significantly as a result of phytase supplementation, reaching an upper level of 74% at an available dietary phosphorus concentration of 0.71%. Adding fungal phytase to the diets improved the availability of phytate-phosphorus from an average of 6 to 64%. The fish retained 53–79% of the ingested phosphorus, while 24–44% was recovered in the faeces. The particulate phosphorus waste output was significantly higher in faeces from fish fed diets without fungal phytase compared to fish fed phytase supplemented diets. The dissolved/suspended phosphorus waste output represented 2–13% of the ingested phosphorus, and there was a significant increase in the dissolved/suspended phosphorus waste output from fish fed the phytase supplemented diet containing 0.71% available phosphorus, suggesting that the phosphorus requirement was reached at this phosphorus level. Consistent with this, there was a substantial increase in the dissolved/suspended phosphorus waste output from fish fed the phytase supplemented diet containing 0.81% available phosphorus, suggesting that the phosphorus requirement was exceeded in this group.This study demonstrated that phytase supplementation will be advantageous to the fish and the environment if supplemented to low-phosphorus diets containing a large share of plant-derived protein. Conversely, the results demonstrated that fungal phytase should not be supplemented to diets in which the available phosphorus level already meets the requirement of the fish, as this will lead to a significant increase in the dissolved/suspended phosphorus waste output.     

Sandwich enzyme-linked immunosorbent assay (ELISA) for measuring the concentration of, and detection of antibodies to, Aujeszky's disease virus

A double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was developed for measuring Aujeszky's disease virus (ADV) antigen concentration and an inhibition technique based on the former was developed for detection of antibodies to ADV. The results were checked by determining the cytopathic and serum neutralization titres. The correlation was satisfactory in both cases, with correlation coefficients above 0.8. When measuring ADV antigen concentration, the lower limit of detection was 10(3) TCID 50/0.2 ml. The sensitivity of ELISA in detecting antibodies to ADV was found to be superior to that of the serum neutralization test and, thus, enabled the testing of rabbit and guinea-pig sera.     

Genetic differentiation between and within ecotypes of pike (Esox lucius) in the Baltic Sea

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Field experience with two different vaccination strategies aiming to control infections with Actinobacillus pleuropneumoniae in a fattening pig herd

Background

The prevalence of pleurisies recorded at slaughter is increasing in Sweden, and acute outbreaks of actinobacillosis that require antimicrobial treatments have become more frequent. As an increased use of antimicrobials may result in the development of antimicrobial resistance it is essential to develop alternative measures to control the disease. Vaccinations present an appealing alternative to antimicrobial treatments. The aim of this work was to evaluate the potential of two different vaccination strategies in a specialized fattening herd affected by actinobacillosis.

Methods

The study was conducted in a specialized fattening herd employing age segregated rearing in eight units. The herd suffered from infections caused by Actinobacillus pleuropneumoniae serotype 2, confirmed by necropsy and serology. The study included 54 batches of pigs grouped into five periods. Batches of pigs of the second period were vaccinated against actinobacillosis twice, and pigs in the fourth period were vaccinated three times. Batches of pigs of the first, third and fifth period were not vaccinated. Concentrations of serum antibodies to A. pleuropneumoniae and serum amyloid A (SAA) were analysed and production data were recorded.

Results

Despite vaccinating, medical treatments were required to reduce the impact of the disease. The mean incidence of individual treatments for respiratory diseases during the rearing period ranged from 0 to 4.7 ± 1.8%, and was greatest during the triple vaccination period (period IV; p < 0.05 when compared to other groups). A large proportion of the vaccinated pigs seroconverted to A. pleuropneumoniae serotype 2 in the absence of a SAA-response. The prevalence of pleuritis decreased from 25.4 ± 6.5% in the first period to 5.0 ± 3.7% in the fifth period (p < 0.001).

Conclusions

The vaccine did not effectively prevent clinical expression of A. pleuropneumoniae infections, but seroconversion to A. pleuropneumoniae in the absence of a SAA-response in a large number pigs indicated that the vaccine had activated the immune system. Further, the prevalence of pleuritis decreased with time. This indicates that vaccinations together with intensified medical treatments of affected pigs could be useful in reducing the impact of A. pleuropneumoniae serotype 2 infections.