Developmental competence of heat stressed oocytes from Holstein and Limousine cows matured in vitro

The negative effects of heat stress on dairy cattle's fertility have been extensively studied, but the relevant knowledge for beef cattle is rather limited. The aims of this study were to investigate the effects of HS during in vitro maturation on the developmental potential of oocytes derived from Limousine and Holstein cows and to estimate the effect of the differential gene expression of important genes in oocytes, cumulus cells and blastocysts in the growth competence between the breeds. In seven replicates, cumulus oocyte complexes from Holstein and Limousine cows were matured for 24 hr at 39°C (controls C; Hol_39, Lim_39) or at 41°C from hour 2 to hour 8 of IVM (treated T; Hol_41, Lim_41), fertilized, and presumptive zygotes were cultured for 9 days at 39°C. Cleavage and embryo formation rates were evaluated 48 hr post-insemination and on days 7, 8 and 9, respectively. From all groups, subsets of cumulus cells, oocytes and blastocysts were analysed for the relative expression of genes related to metabolism, stress, apoptosis and placentation. No difference was detected in cleavage rate or in blastocyst formation rate among the control groups. In both breeds, heat stress reduced blastocyst yield, but at all days the suppression was higher in Limousines. In Holsteins, altered gene expression was detected in cumulus cells (G6PD, GLUT1) and blastocysts (PLAC8), while in Limousines, differences were found in oocytes (G6PD, HSP90AA1), in cumulus cells (CPT1B, HSP90AA1, SOD2) and blastocysts (DNMT, HSP90AA1, SOD2). It appears that Holstein COCs are more tolerant than Limousine COCs, possibly due to compulsory, production driven selection.     

Determination of anabolic steroids in muscle tissue by liquid chromatography-tandem mass spectrometry

A specific and sensitive method based on liquid chromatography-tandem mass spectrometry using atmospheric pressure chemical ionization (LC-APCI-MS/MS) has been developed for the determination of four anabolic steroids [trenbolone, methylboldenone, methyltestosterone, and norethandrolone] in bovine muscle. Methyltestosterone- d 3 was used as internal standard. The procedure involved enzymatic hydrolysis, extraction with tert-butyl methyl ether, defattening, and final cleanup with solid-phase extraction with Oasis HLB cartridges. The analytes were analyzed by reversed-phase LC-MS/MS, acquiring two diagnostic product ions from the chosen precursor [M + H] (+) for the unambiguous confirmation of hormones. The method was validated according to the European Commission Decision 2002/657/EC for the detection and confirmation of residues in products of animal origin. The limits of detection (LOD) and limits of quantitation (LOQ) were found to be 0.3 ng/g and 1.0 ng/g, respectively. The accuracy and precision have been determined, with recoveries ranging from 83% to 104% and the CV factor not exceeding the value of 7%. The decision limits CCalpha were calculated and ranged from 0.05 to 0.15 ng/g while the detection capabilities CCbeta ranged from 0.09 to 0.25 ng/g. The method proved to be sensitive and reliable and thus renders an appropriate means for residue analysis studies.     

The Image of Fish from Aquaculture Among Europeans: Impact of Exposure to Balanced Information

This study investigated the effect of balanced, nonpersuasive information related to safety, healthiness, and sustainability of aquaculture on the image of farmed fish among European consumers. It was demonstrated that there is neither positive nor negative influence of this type of information on the predominantly positive image of fish from aquaculture. Consumers who were exposed to information related to the EU origin and aquaculture related guarantee reported a more positive image of farmed fish. These results provide valuable input for transparent communication about fish farming practices which might increase consumer trust and will not harm the image of fish from aquaculture. Increasing consumers' knowledge about aquaculture and its positive effects on the image of farmed fish is also discussed as a pathway for maintaining and improving aquaculture's positive image in the future.     

A Comparison of French and English Consumers’ Expectations Regarding Labeled Cod Fillet Products

Consumers in England and France are exposed to different fish products and information at the marketplace. Based on this information and cultural differences, English and French consumers create expectations about fish products. The aim of this study was to compare English and French consumers on: (a) expectations regarding labeling on cod fillet products, (b) important factors when purchasing prepacked and fresh fish, and (c) drivers and barriers to fish consumption. English consumers (n = 120) reported in a survey more positive expectations about thawed products than French consumers (n = 120) due to greater familiarity with relevant labeling information.     

Consumer Preference and Sensory Properties of the Pacific Cupped Oyster (Crassostrea gigas) and the European Flat Oyster (Ostrea edulis)

ABSTRACT

Experts in the oyster supply chain (farmers, retailers, and gourmet chefs) in The Netherlands have suggested that the European flat oyster (Ostrea edulis) has superior sensory qualities compared to the Pacific cupped oyster (Crassostrea gigas). However, scientific evidence is lacking. The aim of this study was to evaluate consumer preferences for these two oyster species and to determine the sensory properties of both species by consumers. Two-alternative forced choice tests were performed with the oysters involving a panel of 74 naïve consumers. No significant differences in preferences between the oyster species were observed by the consumers. Nine sensory attributes of both oyster species were evaluated. Consumers did not observe significant differences between species in the sensory attributes: overall odor intensity, sea odor, mud odor, sweetness, pungency, and firmness. The Pacific cupped oyster was perceived as significantly saltier and more intense in greenness than the European flat oyster. We concluded that only a few sensory properties of the European flat oyster and the Pacific cupped oyster are perceived as being different by untrained consumers.     

Association of health involvement and attitudes towards eating fish on farmed and wild fish consumption in Belgium,Norway and Spain

Consumers in many European countries do not equally meet the recommended daily intake levels for fish consumption. Various factors that can influence fish consumption behaviour have been identified but limited research has been performed on fish consumption behaviour, discriminating between farmed and wild fish. The present survey study confirmed differences in total fish consumption, farmed fish and wild fish consumption behaviour in Belgium, Norway and Spain. Spanish consumers consumed more frequently fish of each category than Norwegian consumers. Belgian consumers reported the lowest consumption frequency of fish. Accordingly, health involvement and attitudes towards fish consumption decreased from Spain over Norway to Belgium, suggesting a positive association of health involvement and attitudes towards fish consumption with total fish consumption. Similar effects were found for farmed and wild fish consumption. In general, consumers in all countries were poorly aware of the origin of the fish they consume, despite the mandatory indication of origin on fish labels. Across countries, an increased awareness about fish origin was found with increased fish consumption. The findings of the study indicate that farmed and wild fish consumption should be further stimulated among Belgian, Norwegian and Spanish consumers in association with a healthy and positive meal. Additionally, given the limited awareness of the origin of fish, transparency on the issue of farmed origin will be important in order to anticipate potential adverse communication.     

A Voice-of-Consumer Approach in Development of New Seafood Product Concepts

This article describes a consumer-based approach for development of new seafood product concepts among young adults in Norway and Iceland. The study aim was to gain insight into how young adults determine their acceptance of seafood and make potential product choices. Additional insights measured were confidence in seafood preparation and consumption choices when exposed to specific new seafood concepts. Based on consumer-reported values, three seafood product concepts were evaluated by 354 consumers in a web-based, conjoint experiment in Norway and Iceland. Consumers' evaluations showed a number of consumer preferences for specific seafood product concepts partly associated with and partly conflicting with their original values. Understanding consumer attitudes can help to explain these results. The results of this study will be used as a guide for the next step in developing seafood product concepts.     

Evaluation of Seafood Product Concepts by Young Adults and Families with Young Children from Denmark,Norway, and Iceland

This article describes the results of a study that tested the responses to 14 seafood concepts among young adults and families with young children in Denmark, Norway, and Iceland. This study was aimed at gaining insight into the evaluation of new seafood product concepts by individuals with low seafood consumption. Based on consumer-reported values and previous concept-testing, 14 seafood product concepts were tested by 296 consumers in a web-based experiment. Consumers' preferences depended on the size of fish, the presence of information, and the fish species offered. Young adult consumers evaluated the product concepts differently than parents of young children. Three consumer clusters, based on attitudinal variables, were identified explaining the differences in the evaluation of the product concepts. The outcome of this study will be used to develop a product for realistic in-home testing.     

Fish Quality and Consumers: How Do Consumers’ Knowledge About and Involvement in Fish Quality Define Factors That Influence Fish Buying Behavior?

ABSTRACT

Despite recommendations, fish consumption is low in several countries. One of the many relevant factors that influence fish consumption is the quality of fish products. However, consumers differ in involvement in and knowledge about fish quality. The aim of this study was to reveal differences in involvement and knowledge about fish quality among consumers and measure how these lead to variations in the importance of factors that influence consumers when buying fresh fish fillets. We aimed to explain these results based on subjective and objective knowledge, fish consumption, and social and demographic characteristics. This study was based on data collected from 738 Norwegian consumers who responded to a questionnaire. The survey included items regarding knowledge and involvement in fish quality, objective and subjective knowledge measures, factors important when buying fish, and finally sociodemographic characteristics. This article suggests that perceived quality is one of the most important factors that influence buying behavior when it comes to fish fillet products in Norway. Consumers can have a high or low involvement with and knowledge about fish quality. However, when confronted with the decision of what fish product they may buy, most consumers reported using fish quality as a main driver.     

Genetic diversity and thermotolerance in Holstein cows: Pathway analysis and marker development using whole-genome sequencing

Heat stress causes extensive losses in the dairy sector, due to negative effects on milk production and reproduction. Cows have evolved a series of protective mechanisms, (physiological, biochemical, behavioural) to cope with the thermostressing environments, which have allowed the preservation of productive and reproductive potential of specific animals during summer; these animals are considered thermotolerant and could be used to design programs of selective breeding. These programs, targeting the generations of a population of heat-resistant animals, would increase the frequency of the desired phenotypes, tackling the financial losses on one hand and reducing the carbon footprints of the dairy sector on the other. The development of genomics techniques has enabled genome wide variant calling, to detect SNPs associated with the desired phenotypes. In this study, we used a comparative genomics approach to detect genetic variation associated with thermotolerance and to design molecular markers for characterizing the animals as tolerant/sensitive. A total of 40 cows from each group were split in four sequencing pools and a whole-genome sequencing approach was used. Results and conclusion: Genome-wide genetic variation between groups was characterized and enrichment analysis revealed specific pathways which participate in the adaptive mechanisms of thermotolerance, implicated into systemic and cellular responses, including the immune system functionality, Heat Stress and Unfolded Protein Response. The markers made a promising set of results, as specific SNPs in five genes encoding for Heat Shock Proteins were significantly associated with thermotolerance.