Stress and fear as possible mediators of reproduction problems in group housed sows: a review

The number of herds with group housed non-lactating sows is increasing rapidly in Europe as a consequence of changed legislation initiated by elevated public concern for animal welfare. However, lower litter size and pregnancy rate in group housed compared to individually housed non-lactating sows has been observed in several on-farm studies. Based upon existing knowledge, it is considered whether stress and fear caused by social interactions are possible mediators of impaired reproduction in group housed sows. A review of 15 experiments with group housed sows showed that although the results are few and inconsistent, there are indications that stress and fear may be contributory reasons for the impaired reproduction seen in group housed sows and that possible initiators of stress and fear might be the mixing of unfamiliar sows and high stocking rate levels. A suggestion for indicators of stress and fear related reproduction problems suitable for use in practice are put forward.     

Reliability of an injury scoring system for horses

Background

The risk of injuries is of major concern when keeping horses in groups and there is a need for a system to record external injuries in a standardised and simple way. The objective of this study, therefore, was to develop and validate a system for injury recording in horses and to test its reliability and feasibility under field conditions.

Methods

Injuries were classified into five categories according to severity. The scoring system was tested for intra- and inter-observer agreement as well as agreement with a ''golden standard'' (diagnosis established by a veterinarian). The scoring was done by 43 agricultural students who classified 40 photographs presented to them twice in a random order, 10 days apart. Attribute agreement analysis was performed using Kendall''s coefficient of concordance (Kendall''s W), Kendall''s correlation coefficient (Kendall''s τ) and Fleiss'' kappa. The system was also tested on a sample of 100 horses kept in groups where injury location was recorded as well.

Results

Intra-observer agreement showed Kendall''s W ranging from 0.94 to 0.99 and 86% of observers had kappa values above 0.66 (substantial agreement). Inter-observer agreement had an overall Kendall''s W of 0.91 and the mean kappa value was 0.59 (moderate). Agreement for all observers versus the ''golden standard'' had Kendall''s τ of 0.88 and the mean kappa value was 0.66 (substantial). The system was easy to use for trained persons under field conditions. Injuries of the more serious categories were not found in the field trial.

Conclusion

The proposed injury scoring system is easy to learn and use also for people without a veterinary education, it shows high reliability, and it is clinically useful. The injury scoring system could be a valuable tool in future clinical and epidemiological studies.     

Quality and Shelf Life of Liver of Farmed Cod (Gadus morhua)

ABSTRACT

Livers of Atlantic cod (Gadus morhua) are traditionally used in cod liver oil production or consumed cooked or canned. The farming of cod is a relatively new industry in Norway. The aim of this study was to determine quality and shelf life of fresh liver from farmed cod during chilled storage on ice by hydrolysis and oxidation state and sensory quality and the influence on canned liver. In two experiments, livers from farmed cod were stored chilled and sampled from Days 0 to 13, respectively. Quality, measured as hydrolytic and oxidation degradation, was reduced after 7 days of storage, while sensory quality was reduced after 4 days. Free fatty acids increased from Day 7 in both experiments, while peroxide value and anisidine value showed no change when the livers were single wrapped. Rancid odor was the first sign of oxidation and was registered after three to four days of storage. Canning within 2 days of storage prevented leakage of oil from the canned livers. Sensory analyses of oxidation are recommended as a sensitive and rapid method to detect oxidation of chilled cod liver.     

How is agroforestry perceived in Europe? An assessment of positive and negative aspects by stakeholders

Whilst the benefits of agroforestry are widely recognised in tropical latitudes few studies have assessed how agroforestry is perceived in temperate latitudes. This study evaluates how stakeholders and key actors including farmers, landowners, agricultural advisors, researchers and environmentalists perceive the implementation and expansion of agroforestry in Europe. Meetings were held with 30 stakeholder groups covering different agroforestry systems in 2014 in eleven EU countries (Denmark, France, Germany, Greece, Hungary, Italy, Netherlands, Portugal, Spain, Sweden and the United Kingdom). In total 344 valid responses were received to a questionnaire where stakeholders were asked to rank the positive and negative aspects of implementing agroforestry in their region. Improved biodiversity and wildlife habitats, animal health and welfare, and landscape aesthetics were seen as the main positive aspects of agroforestry. By contrast, increased labour, complexity of work, management costs and administrative burden were seen as the most important negative aspects. Overall, improving the environmental value of agriculture was seen as the main benefit of agroforestry, whilst management and socio-economic issues were seen as the greatest barriers. The great variability in the opportunities and barriers of the systems suggests enhanced adoption of agroforestry across Europe will be most likely to occur with specific initiatives for each type of system.     

Echocardiographic mitral valve prolapse in cavalier King Charles spaniels: epidemiology and prognostic significance for regurgitation

This study investigated the epidemiology and prognostic significance of mitral valve prolapse, detected by ultrasonography, in 153 cavalier King Charles spaniels which were screened consecutively during a period of one year. Seventy-five of the dogs, which had either no murmur or a grade I murmur on screening, were reexamined three years later. The screening revealed that 82 per cent of the dogs aged one to three years and 97 per cent of the dogs over three years had various degrees of mitral valve prolapse. The presence and severity of the condition were independent of gender but correlated positively with age and negatively with bodyweight. The degree of mitral valve prolapse at screening correlated with the regurgitation status (murmur intensity and size of the regurgitant jets) at re-examination and with the percentage increase in the left ventricular end diastolic diameter over the three-year period. The presence of a grade I murmur was not a useful prognostic indicator.     

Incidence of positive heartworm antibody and antigen tests at IDEXX Laboratories: trends and potential impact on feline heartworm awareness and prevention

Data from the IDEXX Laboratories Reference Laboratory Network were retrospectively examined for feline heartworm testing trends in testing frequency, geographic bias, and prevalence for the years 2000--2006. Examination of the data supports the commonly held view that veterinarians do not embrace heartworm disease testing or prevention in cats to the same degree they do in dogs. Despite significant awareness and adoption of heartworm testing and prevention in dogs, we hypothesized that heartworm testing rates are lower for cats than for dogs despite a significant prevalence of feline infection. This is important because a perceived low rate of infection in cats is likely to manifest in a low adoption of testing and prevention. In reality, the overall feline heartworm antigen-positive rate is significant--on average 0.9% over the period studied--and in some regions was estimated to be as high as 4.6%. This compares with an average canine heartworm prevalence rate of 1.2%, a feline leukemia virus prevalence of 1.9%, and a feline immunodeficiency prevalence of 1.0%. Based on the low rate of testing and these prevalence rates, practitioners are routinely missing cases of adult feline heartworm infections and the recently defined heartworm-associated respiratory disease (H.A.R.D). Increased antigen testing would result in detection of a significant number of positive cases. In addition, this population of infected cats would represent the "tip of the iceberg" relative to the greater number of cats that have early infection or are at risk for infection.     

Low feed pellet water stability and fluctuating water salinity cause separation and accumulation of dietary oil in the stomach of rainbow trout (Oncorhynchus mykiss)

Regurgitation (belching) of oil is a problem in sea farmed rainbow trout kept in water with fluctuating salinity. This often coincides with abdominal distension syndrome, which is associated with osmoregulatory stress and lipid indigestion. The present study investigated combined effects of water stability in extruded feeds and fluctuating water salinity on feed consumption, growth, nutrient digestibility, gastrointestinal transit, and accumulation of water and oil in the stomach of rainbow trout. Diets were produced with high or low water stability, which were characterised by a novel water stability test. In an initial 84 days growth experiment, each diet was fed to six groups of 772 g trout, of which three tanks were supplied with full-strength seawater, and three tanks were fluctuated between seawater and freshwater (7 h per day during 3 successive days per week). No significant effects were seen, although the feed intake appeared slightly lowered by low dietary water stability at fluctuating salinity. In a second experiment, each diet was fed to four groups of 1 kg trout, of which two tanks were supplied with full-strength seawater, and two tanks were fluctuated between seawater and brackish water (17‰ 7 h per day daily). Low water stability of the diet resulted in accumulation of oil in the stomach, and this response was worsened when the salinity of the rearing water fluctuated. It also corresponded with reduced lipid digestibility. Consequently, low water stability of the diet caused an oil separation in the stomach that may result in oil-belching in rainbow trout suffering from osmoregulatory stress.     

Inhibition of viral adsorption and penetration by an aqueous extract from Rhododendron ferrugineum L. as antiviral principle against herpes simplex virus type-1

The polyphenol-enriched aqueous extract RF from the aerial parts of Rhododendron ferrugineum exhibited strong antiviral activity against herpes simplex virus type-1 while adenovirus 3 was not affected. RF exhibited an IC₅₀ of 7.4 μg/mL and a selectivity index of 64 when added to the virus inoculum prior to infection. RF abolished virus entry into the host cell by blocking attachment to the cell surface. When added after attachment at a concentration of > 25 μg/mL, RF inhibited also penetration of HSV-1 into the host cell. RF directly interacts with viral envelope proteins as demonstrated for the viral glycoprotein gD.     

OBSERVER VARIATION IN THE TWO-DIMENSIONAL ECHOCARDIOGRAPHIC EVALUATION OF MITRAL VALVE PROLAPSE IN DOGS

In this study, the observer variation and the influence of observer experience in diagnosing mitral valve prolapse in dogs was assessed by having three observers with different degrees of echocardiographic experience (10 years, 4 years, and no prior experience) analyze 303 mitral valve video recordings from 253 dogs, both with and without mitral regurgitation. To assess intraobserver variation, 16 recordings were analyzed twice, and 34 dogs were scanned twice at intervals of a few days. By consensus, 90 dogs had no mitral valve prolapse, 130 had mild and 33 had severe mitral valve prolapse. Intraobserver repeatabilities ranged from 88% to 100% and interobserver repeatabilities from 70% to 78%. In 79% to 94% of the dogs that were scanned twice, the observers diagnosed both recordings identically. All repeatabilities were reduced by approximately 10% when mitral valve prolapse was graded into mild and severe. The three observers differed significantly in diagnosing mitral valve prolapse when compared with each other in pairs (all p-values < 0.01). The unexperienced observer had the highest and most unsystematic occurrence of false diagnoses. It is possible that the interobserver repeatabilities would have been lower had each sonographer obtained his own echocardiograms. We conclude, that mitral valve prolapse in dogs can be diagnosed using two-dimensional echocardiography with the same degree of observer variation as reported in human studies, and that education and training of staff is mandatory to ensure proper ultrasonographic evaluation.