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1.
J Fish Biol ; 2023 Jun 06.
Article in English | MEDLINE | ID: mdl-37278313

ABSTRACT

Sea lice represent a persistent and growing problem, challenging the resilience and growth of the salmon aquaculture industry. In this Norwegian case study, we studied and discuss how the absence of policy instruments directed at stimulating breeding for lice resistance (LR) might be explained. We found well-documented opportunities for selection progress for LR. Hence, breeding on LR appears with an untapped potential. We discuss how market-based, legal, institutional and interest-based factors can explain the absence of policy instruments stimulating LR breeding. Methodologically, we obtained data from document and literature studies and interviews with key players (salmon breeders, farmers, nongovernmental organizations (NGOs) and governmental bodies in Norway). First, LR is a polygenic trait, which makes it poorly suited for patenting. Furthermore, if only a small proportion of fish farmers choose seeds with higher LR, other operators can easily take on the free-rider role because they will not suffer from reduced gain in growth performance as a result of a much stronger emphasis on LR in the breeding goal. The market is thus not expected to stimulate stronger selection for LR in Norwegian salmon breeding. Second, neither genetic engineering (e.g., gene editing), still struggling with consumer acceptance, nor the uncertainty associated with possible changes in the Norwegian Gene Technology Act stimulate investment in LR via, for example, CRISPR technology. Thirdly, public policy instruments in their entirety have targeted other types of innovations against salmon lice, and none have so far been used to stimulate breeding companies to emphasize LR more strongly in their breeding programmes. From a political point of view, it seems that breeding has been left to the market and the private sector. However, neither the NGOs nor the public seem to be aware of, or pay significant attention to, the breeding potential to improve LR and fish welfare. Fragmented management of the aquaculture sector can camouflage the close ties between political and business interests. The industry is hesitant to invest significantly in long-term breeding targets such as significantly higher genetic LR. This may strengthen the assumption that strong economic interests will reduce the role of science in knowledge-based management. As farmed salmon are increasingly being exposed to stressful delousing treatments, mortality and associated welfare problems have increased significantly. For instance, large fish die more often from cardiomyopathy syndrome (CMS), resulting in growing demand for CMS-resistant salmon. This gives rise to a paradoxical situation: increasing treatments with high mortality and fish welfare issues in farmed salmon, while the lice threat to wild salmon persists.

2.
Sci Eng Ethics ; 24(5): 1551-1576, 2018 10.
Article in English | MEDLINE | ID: mdl-28812235

ABSTRACT

Concerns have been voiced about the ethical implications of patenting practices in the field of biotechnology. Some of these have also been incorporated into regulation, such as the European Commission Directive 98/44 on the legal protection of biotechnological inventions. However, the incorporation of ethically based restrictions into patent legislation has not had the effect of satisfying all concerns. In this article, we will systematically compare the richness of ethical concerns surrounding biotech patenting, with the limited scope of ethical concerns actually addressed in the patent system. As sources of our analyses we will use literature and document studies and a survey with important stakeholders and experts related to Norwegian patenting in the aquacultural biotechnology sector. We will structure the analyses with an ethical matrix, developed for this purpose. Showing the misalignment of the discussions within and outside the patent system, we suggest that an important reason for the ethical controversy still surrounding patenting is that ethical questions keep being framed in a narrow way within the system. Until a richer set of ethical considerations is addressed head-on within the patent system, the patent system will continue to evoke academic and interest group criticism, potentially contributing to a legitimacy crisis of the whole system.


Subject(s)
Aquaculture , Bioethical Issues , Biotechnology , Patents as Topic/ethics , Ethical Analysis , Humans , Norway , Patents as Topic/legislation & jurisprudence , Social Control, Formal
3.
PLoS One ; 12(3): e0172711, 2017.
Article in English | MEDLINE | ID: mdl-28257433

ABSTRACT

Tick-borne fever (TBF) is stated as one of the main disease challenges in Norwegian sheep farming during the grazing season. TBF is caused by the bacterium Anaplasma phagocytophilum that is transmitted by the tick Ixodes ricinus. A sustainable strategy to control tick-infestation is to breed for genetically robust animals. In order to use selection to genetically improve traits we need reliable estimates of genetic parameters. The standard procedures for estimating variance components assume a Gaussian distribution of the data. However, tick-count data is a discrete variable and, thus, standard procedures using linear models may not be appropriate. Thus, the objectives of this study were twofold: 1) to compare four alternative non-linear models: Poisson, negative binomial, zero-inflated Poisson and zero-inflated negative binomial based on their goodness of fit for quantifying genetic variation, as well as heritability for tick-count and 2) to investigate potential response to selection against tick-count based on truncation selection given the estimated genetic parameters from the best fit model. Our results showed that zero-inflated Poisson was the most parsimonious model for the analysis of tick count data. The resulting estimates of variance components and high heritability (0.32) led us to conclude that genetic determinism is relevant on tick count. A reduction of the breeding values for tick-count by one sire-dam genetic standard deviation on the liability scale will reduce the number of tick counts below an average of 1. An appropriate breeding scheme could control tick-count and, as a consequence, probably reduce TBF in sheep.


Subject(s)
Ixodes/pathogenicity , Sheep Diseases/microbiology , Tick Infestations/microbiology , Tick-Borne Diseases/microbiology , Anaplasma phagocytophilum/pathogenicity , Animals , Breeding , Ixodes/microbiology , Linear Models , Norway , Sheep , Sheep Diseases/transmission , Sheep, Domestic/microbiology , Tick Infestations/transmission , Tick-Borne Diseases/transmission
4.
Genet Sel Evol ; 46: 5, 2014 Jan 24.
Article in English | MEDLINE | ID: mdl-24461041

ABSTRACT

BACKGROUND: The aim of the study was to estimate genetic parameters for direct and social genetic effects (SGE) for growth and welfare traits in farmed Atlantic cod (Gadus morhua). A SGE refers to the effect of an individual's genes on trait performance of its social partners. In total, 2100 individually tagged juveniles from 100 families at an average age of 222 days post-hatching were used. Each family was separated into three groups of seven fish, and were randomly assigned to 100 experimental tanks, together with fish from two other families. Body weight and length of the first, second and third dorsal fin and the caudal fin measured by digital image analysis were measured at the start of the experiment, after two weeks, and after six weeks. Fin erosion was scored subjectively after six weeks. Variance components estimated using a conventional animal model were compared to those of an animal model including a SGE. RESULTS: Heritabilities from the conventional animal model ranged from 0.24 to 0.34 for body weight and 0.05 to 0.80 for fin length. Heritabilities for fin erosion were highest for the first dorsal fin (0.83 ± 0.08, mean ± standard error) and lowest for the third dorsal fin (0.01 ± 0.04). No significant SGE were found for body weight, whereas SGE for fin lengths were significant after two and six weeks. Contributions to the total heritable variance were equal to 21.5% (6.1 ± 2.1) for the direct effect, 33.1% (9.4 ± 3.2) for the direct-social covariance, and 45.4% (12.9 ± 4.1) for the social variance for length of the first dorsal fin. For fin erosion, SGE were only significant for the second and third dorsal fin. CONCLUSIONS: Including SGE for fin length and fin erosion in the animal model increased the estimated heritable variation. However, estimates of total heritable variances were inaccurate and a larger experiment is needed to accurately quantify total heritable variance. Despite this, our results demonstrate that considering social breeding values for fin length or fin erosion when selecting fish will enable us to improve response to selection for welfare traits in Atlantic cod juveniles.


Subject(s)
Gadus morhua/growth & development , Gadus morhua/genetics , Animals , Body Weight , Breeding , Female , Gadus morhua/anatomy & histology , Male , Models, Biological , Phenotype
5.
Acta Vet Scand ; 53: 30, 2011 May 13.
Article in English | MEDLINE | ID: mdl-21569524

ABSTRACT

BACKGROUND: A major challenge in sheep farming during the grazing season along the coast of south-western Norway is tick-borne fever (TBF) caused by the bacteria Anaplasma phagocytophilum that is transmitted by the tick Ixodes ricinus. METHODS: A study was carried out in 2007 and 2008 to examine the prevalence of A. phagocytophilum infection and effect on weaning weight in lambs. The study included 1208 lambs from farms in Sunndal Ram Circle in Møre and Romsdal County in Mid-Norway, where ticks are frequently observed. All lambs were blood sampled and serum was analyzed by an indirect fluorescent antibody assay (IFA) to determine an antibody status (positive or negative) to A. phagocytophilum infection. Weight and weight gain and possible effect of infection were analyzed using ANOVA and the MIXED procedure in SAS. RESULTS: The overall prevalence of infection with A. phagocytophilum was 55%. A lower weaning weight of 3% (1.34 kg, p < 0.01) was estimated in lambs seropositive to an A. phagocytophilum infection compared to seronegative lambs at an average age of 137 days. CONCLUSIONS: The results show that A. phagocytophilum infection has an effect on lamb weight gain. The study also support previous findings that A. phagocytophilum infection is widespread in areas where ticks are prevalent, even in flocks treated prophylactic with acaricides.


Subject(s)
Anaplasma phagocytophilum/immunology , Anaplasma phagocytophilum/isolation & purification , Antibodies, Bacterial/blood , Ehrlichiosis/veterinary , Sheep Diseases/microbiology , Animals , Body Weight , Ehrlichiosis/epidemiology , Ehrlichiosis/immunology , Ehrlichiosis/microbiology , Female , Ixodes/microbiology , Male , Norway/epidemiology , Prevalence , Seroepidemiologic Studies , Sheep Diseases/epidemiology , Sheep Diseases/immunology , Sheep, Domestic , Tick Infestations/veterinary , Weaning
6.
Acta Vet Scand ; 53: 8, 2011 Feb 11.
Article in English | MEDLINE | ID: mdl-21314927

ABSTRACT

BACKGROUND: It has been questioned if the old native Norwegian sheep breed, Old Norse Sheep (also called Norwegian Feral Sheep), normally distributed on coastal areas where ticks are abundant, is more protected against tick-borne infections than other Norwegian breeds due to a continuously high selection pressure on pasture. The aim of the present study was to test this hypothesis in an experimental infection study. METHODS: Five-months-old lambs of two Norwegian sheep breeds, Norwegian White (NW) sheep and Old Norse (ON) sheep, were experimentally infected with a 16S rRNA genetic variant of Anaplasma phagocytophilum (similar to GenBank accession number M73220). The experiment was repeated for two subsequent years, 2008 and 2009, with the use of 16 lambs of each breed annually. Ten lambs of each breed were inoculated intravenously each year with 0.4 ml A. phagocytophilum-infected blood containing approximately 0.5 × 106 infected neutrophils/ml. Six lambs of each breed were used as uninfected controls. Half of the primary inoculated lambs in each breed were re-challenged with the same infectious dose at nine (2008) and twelve (2009) weeks after the first challenge. The clinical, haematological and serological responses to A. phagocytophilum infection were compared in the two sheep breeds. RESULTS: The present study indicates a difference in fever response and infection rate between breeds of Norwegian sheep after experimental infection with A. phagocytophilum. CONCLUSION: Although clinical response seems to be less in ON-lambs compared to NW-lambs, further studies including more animals are needed to evaluate if the ON-breed is more protected against tick-borne infections than other Norwegian breeds.


Subject(s)
Anaplasma phagocytophilum , Ehrlichiosis/veterinary , Genetic Predisposition to Disease , Sheep Diseases/microbiology , Animals , Antibodies, Bacterial/blood , Ehrlichiosis/genetics , Ehrlichiosis/immunology , Ehrlichiosis/microbiology , Sheep , Sheep Diseases/genetics , Sheep Diseases/immunology , Weight Gain
7.
Lipids Health Dis ; 9: 37, 2010 Apr 15.
Article in English | MEDLINE | ID: mdl-20398309

ABSTRACT

Chicken meat with reduced concentration of arachidonic acid (AA) and reduced ratio between omega-6 and omega-3 fatty acids has potential health benefits because a reduction in AA intake dampens prostanoid signaling, and the proportion between omega-6 and omega-3 fatty acids is too high in our diet. Analyses for fatty acid determination are expensive, and finding the optimal number of analyses to give reliable results is a challenge. The objective of the present study was i) to analyse the intraclass correlation of different fatty acids in five meat samples, of one gram each, within the same chicken thigh, and ii) to study individual variations in the concentrations of a range of fatty acids and the ratio between omega-6 and omega-3 fatty acid concentrations among fifteen chickens. Fifteen newly hatched broilers were fed a wheat-based diet containing 4% rapeseed oil and 1% linseed oil for three weeks. Five muscle samples from the mid location of the thigh of each chicken were analysed for fatty acid composition. The intraclass correlation (sample correlation within the same animal) was 0.85-0.98 for the ratios of total omega-6 to total omega-3 fatty acids and of AA to eicosapentaenoic acid (EPA). This indicates that when studying these fatty acid ratios, one sample of one gram per animal is sufficient. However, due to the high individual variation between chicken for these ratios, a relatively high number of animals (minimum 15) are required to obtain a sufficiently high power to reveal significant effects of experimental factors (e.g. feeding regimes). The present experiment resulted in meat with a favorable concentration ratio between omega-6 and omega-3 fatty acids. The AA concentration varied from 1.5 to 2.8 g/100 g total fatty acids in thigh muscle in the fifteen broilers, and the ratio between AA and EPA concentrations ranged from 2.3 to 3.9. These differences among the birds may be due to genetic variance that can be exploited by breeding for lower AA concentration and/or a more favorable AA/EPA ratio to produce meat with health benefits.


Subject(s)
Arachidonic Acid/analysis , Eicosapentaenoic Acid/analysis , Muscle, Skeletal/chemistry , Poultry , Animals , Chickens , Diet , Fatty Acids, Omega-3/analysis , Fatty Acids, Omega-6/analysis , Meat/analysis
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