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The Nordic countries are committed to conserving farm animal genetic diversity. National reports on phenotypic and genetic characterization point towards a lack of characterization for many Nordic ...

The Norwegian Lundehund is a highly endangered native dog breed. Low fertility and high frequency predisposition to intestinal disorder imply inbreeding depression. We assessed the genetic diversity of the Lundehund population from pedigree data and evaluated the potential of optimal contribution selection and cross-breeding in the long-term management of the Lundehund population. The current Norwegian Lundehund population is highly inbred and has lost 38.8% of the genetic diversity in the base population. Effective population size estimates varied between 13 and 82 depending on the method used. Optimal contribution selection alone facilitates no improvement in the current situation in the Lundehund due to the extremely high relatedness of the whole population. Addition of (replacement with) 10 breeding candidates of foreign breed to 30 Lundehund breeders reduced the parental additive genetic relationship by 40–42% (48–53%). Immediate actions are needed to increase the genetic diversity in the current Lundehund population. The only option to secure the conservation of this rare breed is to introduce individuals from foreign breeds as breeding candidates. © 2017 Kettunen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Capelin (Mallotus villosus) displays alternative reproductive modes throughout its circumpolar distribution. This predicts divergent thermohaline tolerance of eggs because they are incubated in either a steady offshore or variable intertidal environment. We investigate herein thermohaline tolerance of eggs from the offshore spawning Barents Sea capelin. Subsequently, we compare our data with those previously published on other offshore and intertidal spawning capelin populations across the Northeast Atlantic Ocean, with the aim of determining possible patterns in the thermohaline tolerance of eggs from the alternative reproductive modes. In a 2 × 4 factorial design various combinations of salinities and temperatures had only negligible effect on the survival of eggs until first hatch. The embryonic development rate from fertilisation until first hatch across populations and between the two reproductive modes suggested non-local thermohaline tolerance towards the physical factors during development. Finally, no differences were observed in salinity tolerance from fertilisation to first hatch between populations representing different reproductive modes. The present findings demonstrate wide thermohaline tolerance of capelin eggs regardless of population origin and reproductive mode.

We present a novel KING breeding design to produce genetically protected homogeneous fish material for commercial producers from a breeding nucleus. KING F2-production population is established from the nucleus, first through full-sib mating within two unrelated high-quality families to produce inbred F1-progeny and then resolving the inbreeding in F2 through mating of the unrelated F1-individuals. Owing to a small number of founders and the inbred F1-parents, the remaining additive genetic variance is 37.5% of the original. This restricts the use of F2-progeny to establish new breeding programmes, thereby protecting the genetic material of the nucleus. The theoretical calculations show that a concomitant decrease of phenotypic variance is possible. However, the reduction is considerable only for traits with high heritability (h2 > 0.50). The method was tested with rainbow trout. The results revealed that the mean body weight of the KING-progeny was similar, but, surprisingly, phenotypic variation (especially due to residual variance) was higher compared with either their outbred control group or the nucleus breeding population. Although further evaluation of this breeding design is needed, the results suggest that while genetic protection is achieved, the efficiency of the method to reduce phenotypic variation is limited for economically important traits with low-to-moderate heritability.

The aims of this study were to estimate genetic (co)variance components of Atlantic cod for body weight at 2.5 years of age (BW) and resistance to vibriosis (a bacterial disease) and viral nervous necrosis (VNN). The traits were recorded on seven discrete year-classes: five year-classes for vibriosis (11,936 individuals), two year-classes for VNN (6185 individuals) and five year-classes for BW (22,703 individuals), with each trait recorded on separate sub-samples of the full-sib families. Three genetic groups were defined in the dataset: coastal cod south (CCS), coastal cod north (CCN) and north-east Arctic cod (NEAC). Significant differences between the groups were found only for VNN resistance, with expected survival rates of (approx.) 52% vs. 13% in CCS and NEAC, respectively. Furthermore, significant favorable heterosis was estimated for BW (+ 147 g) and vibriosis resistance (~ 22% relative increase in survival). All three traits had significant heritability estimates, with a moderate heritability for vibriosis resistance (0.16 ± 0.04), exceptionally high heritability for VNN resistance (0.68 ± 0.14) and a moderate to high heritability for BW (0.28 ± 0.05). All estimated genetic correlations between the traits were weak and not significantly different from zero. Common environmental family effects explained 5.6% and 6.6% of the liability variance for vibriosis and VNN, and 8.6% of the phenotypic variance for BW. The significant heritabilities and low genetic correlations indicate that joint genetic improvement of vibriosis resistance, VNN resistance and growth rate would be feasible.

The effects of thermal treatments on induction of triploidy in Atlantic cod have been investigated. Cold shock [−1.7±0.1°C at 20 min post fertilization (PF) for 2 h] was based on a previously developed protocol, and heat shocks, below the lethal threshold of 24°C, were at 16, 18 or 20°C applied 20, 30 or 40 min PF for 20 min. Cold shock did not affect larval survival and was ineffective for producing triploids (range 0–4%). A heat shock of 20°C at 20 min PF generated the highest percentages (range 66–100%) of triploid larvae at hatching, with survival ranging from 10% to 20% relative to the controls. Lower heat shock temperatures or delayed shocks increased survival but decreased the number of triploids, providing no net gain in triploid yield (range 1–9%). Heat shocks applied later than 20 min PF produced 2–4% tetraploid larvae at hatching. A thermal shock of 20°C initiated at 20 min PF and lasting 20 min proved to be the most generally efficient treatment for induction of triploidy in Atlantic cod.

The objective of this study was to assess between-family differences in resistance to vibriosis in Atlantic cod. Twenty full-sib families, of which 13 were of Norwegian coastal cod (CC) and 7 families represented northeast Arctic cod (NEAC), were tested for survival after challenge with Vibrio anguillarum. Mortality after challenge was recorded daily, and the experiment was terminated 22 days post challenge. The overall survival at the end of the experiment was 12.3%. Significant family differences in the survival patterns were found both at the end of the test and 8 days after challenge (approximating 50% mortality). In this study, CC (14.2% survival) proved to be more resistant to vibriosis than NEAC (8.6% survival). Although further investigations are needed to quantify the amount of additive genetic variation in vibriosis resistance, this study gives an indication that challenge test results may successfully be used as selection criteria for disease resistance to classical vibriosis in Atlantic cod.

Climate change is expected to have a profound impact on natural resources, and thus on the primary industries (agriculture, forestry and fisheries) in the Nordic countries. Climate change induces r ...

Tutkimuksessa tarkasteltiin ayrshire-ensikoiden maidontuotannon perinnollisia tunnuslukuja laktaation eri vaiheissa koelypsykohtaisten mittausten perusteella. Aineisto koottiin Maatalouden Laskentakeskuksen karjantarkkailurekisterista kolmen eri maaseutukeskuksen alueelta (Pohjois-Savo, Keski-Pohjanmaa ja Lappi). Koelypsytulokset numeroitiinkymmeneen luokkaan sen mukaan, kuinka monta paivaa oli kulunut poikimisesta mittauspaivaan mennessa (DIM). Numeroidut koelypsyt luokiteltiin edelleen kolmeksi ominaisuudeksi lypsykauden vaiheen mukaan siten, etta kaksi ensimmaista koelypsya muodostivat ensimmaisen ominaisuuden (1-60 DIM), nelja seuraavaa toisen ominaisuuden (61-180 DIM) ja nelja viimeista kolmannen ominaisuuden (181-305 DIM). Varianssikomponentit arvioitiin usean ominaisuuden toistuvuus-elainmallilla kayttamalla REML-menetelmaa (restricted maximum likelihood) ja AI-algoritmia (average information). Periytymisasteiden arviot koelypsykohtaisille maitotuotoksille laktaation eri vaiheissa (0,11-0,17) olivat alhaisempia kuin kirjallisuudessa esitetyt. Erityisesti laktaation keskivaiheen maitotuotos on yleisesti arvioitu voimakkaammin periytyvaksi ominaisuudeksi kuin mihin taman tutkimuksen tulos viittaa. Ominaisuuksien valiset geneettiset korrelaatiot vaihtelivat valilla 0,64-0,91. Periytymisasteiden ja geneettisten korrelaatioiden keskivirheet olivat pienia (0,02-0,08). Alhaiset periytymisasteiden arviot voivat olla seurausta kaytetysta mallista tai aineiston rakenteesta aiheutuvasta mahdollisesta mallin tekijoiden paallekkaisyydesta. Tulosten perusteella voidaan paatella, etta maidontuotanto lypsykauden eri vaiheessa ei maaraydy taydellisesti samojen geenien perusteella. On todennakoista, etta elainten paremmuusjarjestys jonkin verran poikkeaa koko lypsykauden koelypsytulosten perusteella tehdyn arvostelun paremmuusjarjestyksesta, jos elaimet arvostellaan lypsykauden alun koelypsytulosten perusteella. Tutkimuksen tulokset tukevat oletusta, etta lypsykayran muodossa on additiivista geneettista vaihtelua. Elaimen poikkeama yleisesta lypsykayrasta on syyta mallintaa esimerkiksi satunnaisten regressiokertoimien avulla, kun arvioidaan elaimen jalostusarvoa koelypsymallilla. Talloin elaimen jalostusarvoksi tulee sen tuotostason ja lypsykayran muodon yhdistelma.

A preconditioned conjugate gradient method was implemented into an iteration on a program for data estimation of breeding values, and its convergence characteristics were studied. An algorithm was used as a reference in which one fixed effect was solved by Gauss-Seidel method, and other effects were solved by a second-order Jacobi method. Implementation of the preconditioned conjugate gradient required storing four vectors (size equal to number of unknowns in the mixed model equations) in random access memory and reading the data at each round of iteration. The preconditioner comprised diagonal blocks of the coefficient matrix. Comparison of algorithms was based on solutions of mixed model equations obtained by a single-trait animal model and a single-trait, random regression test-day model. Data sets for both models used milk yield records of primiparous Finnish dairy cows. Animal model data comprised 665,629 lactation milk yields and random regression test-day model data of 6,732,765 test-day milk yields. Both models included pedigree information of 1,099,622 animals. The animal model {random regression test-day model} required 122 305 rounds of iteration to converge with the reference algorithm, but only 88 {149} were required with the preconditioned conjugate gradient. To solve the random regression test-day model with the preconditioned conjugate gradient required 237 megabytes of random access memory and took 14% of the computation time needed by the reference algorithm.