Effects of cage type and gnawing blocks on weight gain, organ weights and open-field behaviour in wistar rats

Two separate experiments were conducted to study the environmental enrichment value of aspen gnawing blocks in solid bottom cages with bedding '(SBC) and in grid floor cages without bedding (GFC), and the effects of housing environments on the physiology and behaviour of male outbred Wistar rats (n=90). Animals were housed in groups of 3 from weaning until the age of 8-12 weeks. The behaviour of animals in the first experiment was tested in five minute open-field tests at the age of 8 and 12 weeks. Rats gnawed blocks about four times more in GFCs than in SBCs (p<0.01). In the first experiment, animals housed in GFCs had heavier adrenal glands (p<0.001) but lower serum corticosterone concentrations (p<0.01) and their weight gain was greater than animals housed in SBCS (p<0.000). The presence of blocks in cages decreased the weight gain in both cage types (p<0 001) In the first open-field test, the animals without blocks in both cage types decreased their activity in the central area during the last 2.5 min of the test (p<0.01). The similar effect of blocks was also seen in animals later transferred into GFCs (p<0.05). These rats without blocks were also less active in the periphery (p<0.01) and had more standing alert behaviour (p<0.01) than animals with gnawing blocks. In both open-field tests, rats housed in SBCs showed more grooming behaviour than animals in GFCs (p<0.05). In the second experiment. animals in GFCs had again enlarged adrenals (p<0.05) and their brown adipose tissue weights were slightly increased (p<0.05) Altogether, SBC as a living environment resulted in lighter animals with smaller adrenals. but higher serum eortieosterone concentrations. In the openfield, blocks seemed to result in more active and less timid animals and antagonize the effects of housing in GFCs. Aspen gnawing blocks can be recommended as enrichment objects especially in GFCs

The use of aspen blocks and tubes to enrich the cage environment of laboratory rats

Female and male outbred Wistar rats (n=48) were allocated into three groups at weaning; control, tube and block groups (n = 8 males and 8 females in each) Animals were conventionally housed for five weeks in groups of four per cage with either an aspen tube (20x12x12 cm) or an aspen block (6x6x6 cm) in addition to the aspen bedding. The control animals had no enrichment items in their cages. The use of tube and block was assessed by measuring both the volume gnawed and via video recordings, which were done by the instantaneous sampling method at 1 min intervals. The growth of the animals was followed by weighing the animals three times during the study. Rats with the tubes in their cage spent over, 80 % of their time during light period inside the tube and over 20 % during dark period. Furthermore, when the lights were turned off, rats increased other contacts (on and beside) with the tube from 5 % to about 40 %. Animals with blocks spent about 3 % of their time during the light period on top of the block or in its vicinity and about 11 % during the dark period. The amount gnawed was essentially the same with both items and increased slightly with time. The enrichment items did not have any effects on the growth of the animals. In conclusion, the enrichment items have the advantage of not introducing any extra or new compounds into the cage environment, since they are made from the same raw material as the bedding. The rats used the items not only for gnawing but also for other activities. The inside of the tube was mainly used as shelter from the light The aspen tube seemed to have more enrichment value for rats than the aspen block‘ since it allowed a wider range of behaviour patterns to be expressed. These items were reusable, economical and species-appropriate for en riching the cage environment of laboratory rats. Keywords: environmental enrichment, gnawing, rat

Environmental enrichment may alter the number of rats needed to achieve statistical significance

Currently, environmental enrichment studies have focused on detection of differences in group means resulting from varied enrichments. The effects of enrichment procedures on variation and hence on study results have received far less attention. Within group variation in studies is directly related to adequate sample size and thus determines ethically correct number of animals to be used. The aim of this study was to evaluate the effects of enrichment items on clinical chemistryand physiological parameters of Wistar rats with the emphasis on the extent of variation. Fortyeight weaned female and male outbred Wistar rats from eight different litters were housed for five weeks in groups of four rats per cage with anaspen tube (20x12x12 em), an aspen block (6x6x6 cm) or without enrichment items (control animals). At the end of the study, adrenals and brown adipose tissues were weighed, growth calculated from initial and final body weights and thefollowing assays were performed from serum samples: AFOS, ALAT, ASAT, LDH, GGT, Pi, Ca, cholesterol, triglycerides, ereatinine, total bilirubin, protein and corticosterone. Based on the variation detected, SOLO Power Analysis was used to calculate the smallest number of animals required (n) to detect an arbitrarily chosen 20 % difference in all means, when significance was set at p=0.05 and statistical power at 0.90. Based on the n-values, additional N-ratio (nenrichment / ncontrol) was calculated to indicate, how many times more or less animals were needed in the enrichment group in comparison to the control group. The enrichment items did not have effects on group means. However. they seemed to influence the variation and hence on the number of animals needed, with enzyme parameters being the most sensitive in this respect. This relationship between enrichment, variation and number of animals needed should be kept in mind while designing experiments with ethically correct sample size

FINRES-Vet 2021 : Finnish Veterinary Antimicrobial Resistance Monitoring and Consumption of Antimicrobial Agents

Authors and institutions participating in making the FINRES-Vet report: Finnish Food Authority: Suvi Nykäsenoja, Satu Olkkola, Marie Verkola, Mia Biström, Thomas Grönthal, Tiina Autio, Liisa Kaartinen, Mirja Raunio-Saarnisto Finnish Medicines Agency Fimea: Katariina Kivilahti-Mäntylä, Tita-Maria Muhonen Faculty of Veterinary Medicine, University of Helsinki: Katarina EskolaSales of veterinary antibiotics turned to a 5% increase in 2021. The result, however, was the second lowest since the monitoring began. The majority of overall sales consisted of products for individual treatment and the proportion of products for group treatment was roughly over a quarter. The biggest increase in sales was noted for orally administered sulfa-trimethoprim-combination and is partly explained by the increased manufacture of medicated feed for fur animals. Increased sales were also noted for antibiotic tablets for companion animals. Injectable penicillin continued to be the most sold veterinary antibiotic. Sales of critically important antibiotics (HPCIA, WHO) for treatment of animals decreased further and remained very low. The antibiotic resistance situation in bacteria from animals and food has remained relatively good in Finland. However, in certain bacterial species resistance was detected in moderate or high levels. Therefore, the need remains to further emphasise the preventive measures and prudent use of antibiotics. It is important to follow the Finnish recommendations for the use of antimicrobials in animals. Among salmonella from food-producing animals and campylobacter from broilers, resistance levels were low. Since 2014, the proportions of fluoroquinolone and tetracycline resistant broiler campylobacter isolates have varied. Among porcine campylobacter, fluoroquinolone resistance has increased. Resistance situation among indicator E. coli from pigs has remained good. The prevalence of ESBL/AmpC-producing bacteria in slaughtered pigs increased in 2021 while no ESBL/AmpC-producing bacteria were detected in pork and beef at retail. MRSA bacteria were detected more than previously in fresh pork at retail. The resistance situation among pathogenic bacteria isolated from food-producing animals remained similar to 2020. Resistance was overall low in bovine and porcine respiratory pathogens as well as in pathogens isolated from broilers. Resistance was still detected most in enterotoxigenic E. coli from pigs. Among bacteria isolated from companion animals, the changes in resistance situation were mostly small. The proportion of canine E. coli strains resistant to third-generation cephalosporins was the lowest since the start of the monitoring

FINRES-Vet 2018 : Finnish Veterinary Antimicrobial Resistance Monitoring and Consumption of Antimicrobial Agents

Consumption of veterinary antimicrobials in food-producing animal species in Finland is low and in recent years, has decreased further. Drop is noted in sales of almost all antimicrobial classes. Particularly sales of orally administered products have decreased. Sales of tablets intended to companion animals has almost halved during this decade. Majority, two thirds, of all antimicrobial products sold in 2018 was for treatment of individual animals and the remaining third products applicable for group treatment. Narrow spectrum penicillin G was the most used antimicrobial for animals and the proportion of highest priority critically important antimicrobials (HPCIA) was very low. The antimicrobial resistance situation in bacteria from animals and food has remained relatively good in Finland. However, in certain bacteria resistance was detected in moderate or high levels. Therefore, there is a need to further emphasise the preventive measures and prudent use of antimicrobials. It is important to follow the Finnish recommendations for the use of antimicrobials in animals. Among salmonella and campylobacter isolated from Finnish food-producing animals, resistance levels were mainly low. For the first time in Finland, multidrug resistant S. Kentucky was isolated from cattle in 2018. From 2014, the occurrence of fluoroquinolone and tetracycline resistance in campylobacter from broilers have varied. The occurrence of fluoroquinolone resistance in indicator E. coli has increased although the resistance is still low. Among pathogenic bacteria isolated from food-producing animals the most notifiable change was the worsening of resistance in some bovine respiratory disease pathogens. In other pathogens from food-producing animals the resistance situation remained similar as in previous years. The proportion of resistant bacterial isolates from companion animals and horses decreased for nearly all antimicrobials. However, the proportion of resistant isolates is still high for some antimicrobials. ESBL/AmpC-producing bacteria were still encountered in broilers and broiler meat; prevalence of these bacteria in broiler meat was somewhat lower in 2018 compared to 2016

Genetic Variants on Chromosome 1p13.3 Are Associated with Non-ST Elevation Myocardial Infarction and the Expression of DRAM2 in the Finnish Population

Myocardial infarction (MI) is divided into either ST elevation MI (STEMI) or non-ST elevation MI (NSTEMI), differing in a number of clinical characteristics. We sought to identify genetic variants conferring risk to NSTEMI or STEMI by conducting a genome-wide association study (GWAS) of MI stratified into NSTEMI and STEMI in a consecutive sample of 1,579 acute MI cases with 1,576 controls. Subsequently, we followed the results in an independent population-based sample of 562 cases and 566 controls, a partially independent prospective cohort (N = 16,627 with 163 incident NSTEMI cases), and examined the effect of disease-associated variants on gene expression in 513 healthy participants. Genetic variants on chromosome 1p13.3 near the damage-regulated autophagy modulator 2 gene DRAM2 associated with NSTEMI (rs656843; odds ratio 1.57, P = 3.11 x 10(-10)) in the case-control analysis with a consistent but not statistically significant effect in the prospective cohort (rs656843; hazard ratio 1.13, P = 0.43). These variants were not associated with STEMI (rs656843; odds ratio, 1.11, P = 0.20; hazard ratio 0.97, P = 0.87), appearing to have a pronounced effect on NSTEMI risk. A majority of the variants at 1p13.3 associated with NSTEMI were also associated with the expression level of DRAM2 in blood leukocytes of healthy controls (top-ranked variant rs325927, P = 1.50 x 10(-12)). The results suggest that genetic factors may in part influence whether coronary artery disease results in NSTEMI rather than STEMI.Peer reviewe

Contemporary radiation doses in interventional cardiology: a nationwide study of patient doses in Finland

The amount of interventional procedures such as percutaneous coronary intervention (PCI), transcatheter aortic valve implantation (TAVI), pacemaker implantation (PI) and ablations has increased within the previous decade. Simultaneously, novel fluoroscopy mainframes enable lower radiation doses for patients and operators. Therefore, there is a need to update the existing diagnostic reference levels (DRLs) and propose new ones for common or recently introduced procedures. We sought to assess patient radiation doses in interventional cardiology in a large sample from seven hospitals across Finland between 2014 and 2016. Data were used to set updated national DRLs for coronary angiographies (kerma-air product (KAP) 30 Gycm2) and PCIs (KAP 75 cm2), and novel levels for PIs (KAP 3.5 Gycm2), atrial fibrillation ablation procedures (KAP 25 Gycm2) and TAVI (KAP 90 Gycm2). Tentative KAP values were set for implantations of cardiac resynchronization therapy devices (CRT, KAP 22 Gycm2), electrophysiological treatment of atrioventricular nodal re-entry tachycardia (6 Gycm2) and atrial flutter procedures (KAP 16 Gycm2). The values for TAVI and CRT device implantation are published for the first time on national level. Dose from image acquisition (cine) constitutes the major part of the total dose in coronary and atrial fibrillation ablation procedures. For TAVI, patient weight is a good predictor of patient dose.</p