| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Andersson, Lisa, et al.
(författare)
-
The same ELA class II risk factors confer equine insect bite hypersensitivity in two distinct populations
- 2012
-
Ingår i: Immunogenetics. - : Springer Science and Business Media LLC. - 0093-7711 .- 1432-1211. ; 64:3, s. 201-208
-
Tidskriftsartikel (refereegranskat)abstract
- Insect bite hypersensitivity (IBH) is a chronic allergic dermatitis common in horses. Affected horses mainly react against antigens present in the saliva from the biting midges, Culicoides ssp, and occasionally black flies, Simulium ssp. Because of this insect dependency, the disease is clearly seasonal and prevalence varies between geographical locations. For two distinct horse breeds, we genotyped four microsatellite markers positioned within the MHC class II region and sequenced the highly polymorphic exons two from DRA and DRB3, respectively. Initially, 94 IBH-affected and 93 unaffected Swedish born Icelandic horses were tested for genetic association. These horses had previously been genotyped on the Illumina Equine SNP50 BeadChip, which made it possible to ensure that our study did not suffer from the effects of stratification. The second population consisted of 106 unaffected and 80 IBH-affected Exmoor ponies. We show that variants in the MHC class II region are associated with disease susceptibility (p(raw)=2.34x10(-5)), with the same allele (COR112:274) associated in two separate populations. In addition, we combined microsatellite and sequencing data in order to investigate the pattern of homozygosity and show that homozygosity across the entire MHC class II region is associated with a higher risk of developing IBH (p=0.0013). To our knowledge this is the first time in any atopic dermatitis suffering species, including man, where the same risk allele has been identified in two distinct populations.
|
|
| 6. |
|
|
| 7. |
- Arvelius, Per, et al.
(författare)
-
Does the Swedish Armed Forces’ temperament test give information on genetic differences between dogs?
- 2013
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- With the purpose to select breeders and dogs for training, all German Shepherd dogs in the Swedish Armed Forces (SAF) breeding program go through a temperament test. During the test, the dog's behavioural responses are rated with two different methods. In a previous study, using PCA on the test items, five and three underlying behavioural dimensions from each rating method were defined. Three of the dimensions correlated significantly to training success. Using test results from 873 dogs, we estimated heritabilities of, and genetic correlations between, the 38 test items plus the eight underlying behavioural dimensions. Parameters were estimated using a linear animal model including fixed effects of sex, educational level, test age and interaction between test year and test arena, and random effect of litter, genetic effect of the individual and residual. Heritabilities ranged from 0.00 to 0.28 (SE=0.05- 0.10), which is similar to what has been reported in previous studies on traits defined and measured in a comparable way. Genetic correlations were high (rg=0.92-0.98, SE=0.08-0.12) between dimensions derived from each registration method and defined as confidence, engagement and aggressiveness, but relatively weak between these dimensions within registration method (rg=0.00-0.45, SE=0.29-0.41). Our results imply that the test measures three separate behavioural dimensions and that the SAF temperament test as a whole is possible to utilize for selection of dogs for breeding, but also that some test items should be measured differently to be meaningful for selection purposes. Furthermore, aggregating variables based on a PCA performed on phenotypic data might be sub-optimal when defining dimensions for breeding purposes.
|
|
| 8. |
- Arvelius, Per, et al.
(författare)
-
Genetic analysis of a temperament test as a tool to select against everyday life fearfulness in Rough Collie
- 2014
-
Ingår i: Journal of Animal Science. - : Oxford University Press (OUP). - 0021-8812 .- 1525-3163. ; 92, s. 4843-4855
-
Tidskriftsartikel (refereegranskat)abstract
- Fear-related problems are common among Rough Collies in Sweden. Annually, on average, >200 Rough Collies are subjected to the dog mentality assessment (DMA), a temperament test during which 33 behavioral reactions are rated. Previous research has shown that a dog's DMA result can be condensed into 5 underlying personality traits. The aim of the study was to evaluate if it is possible to use the DMA for selection for temperament in Swedish Rough Collies, in particular to decrease everyday life fearfulness. We also wanted to compare 2 methods to compute the personality traits: summated scales (SS) and factor scores (FS). The DMA data for 2,953 Rough Collies were used to estimate genetic parameters for the 5 personality traits (both SS and FS), using a linear animal model including fixed effects of sex, year and month of test, and random effects of litter, judge, test occasion, genetic effect of the individual, and residual. Age at test was included as linear and quadratic regressions. The DMA personality trait heritability estimates ranged from 0.13 to 0.25. The SS showed greater or equal heritability estimates compared with the FS. To validate the DMA, data on everyday life behavior of 1,738 Rough Collies were collected using an extended version of the Canine Behavioral Assessment and Research Questionnaire. Each dog's questionnaire result was condensed into 18 underlying behavioral subscales. Genetic parameters for the subscales were estimated using a linear animal model, including a fixed effect of sex and random genetic effect of the individual and residual. Age when the questionnaire was completed was included as linear and quadratic regressions. Heritability estimates for the questionnaire subscales were 0.06 to 0.36. There were high and significant genetic correlations between DMA personality traits and questionnaire subscales. For instance, the DMA personality trait Curiosity/Fearlessness correlated strongly genetically to the questionnaire subscale Non-social fear (-0.70), DMA Sociability to Stranger-directed interest (0.87) and Stranger-directed fear (-0.80), DMA Playfulness to Human-directed play interest (0.63), and DMA Chase-proneness to Chasing (0.73). We could not detect any obvious difference in validity between DMA SS and FS. We conclude that the DMA is an effective tool for selection of breeding animals with the goal to decrease everyday life fearfulness among Swedish Rough Collies. The DMA can also be used for breeding for other traits. The SS method seems to perform at least as good the FS method.
|
|
| 9. |
- Arvelius, Per, et al.
(författare)
-
Good Possibilities to Select Against Fearfulness in Rough Collie
- 2014
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Fear-related problems are common among Swedish Rough Collies. Genetic analyses were performed on 4 composite behavioral traits based on 2953 Rough Collie results from a temperament test. Heritabilities ranged from 0.13-0.25. Validation of the test was done using a dog owner questionnaire, which generated information about everyday life behavior for 1738 Rough Collies. There were high and significant genetic correlations between traits measured in the test, and the everyday life behavior of the dogs as described by the owners. For instance, Curiosity/fearlessness in the test was negatively genetically correlated with Nonsocial fear in the questionnaire (-0.70, SE 0.10). We conclude that data from the analyzed test is possible to use for selection to decrease everyday life fearfulness in the Swedish Rough Collie population.
|
|
| 10. |
- Arvelius, Per, et al.
(författare)
-
The Swedish Armed Forces temperament test gives information on genetic differences among dogs
- 2014
-
Ingår i: Journal of Veterinary Behavior: Clinical Applications and Research. - : Elsevier BV. - 1558-7878 .- 1878-7517. ; 9, s. 281-289
-
Tidskriftsartikel (refereegranskat)abstract
- With the dual purpose of selecting both breeding animals and dogs for training, all German shepherd dogs in the Swedish Armed Forces (SAF) breeding program are subjected to a temperament test. During the test, the dog's behavioral responses are rated with 2 different methods. In a previous study, using Principal Components Analysis (PCA) on the test items, 5 and 3 underlying behavioral dimensions from each rating method were defined. Three of the dimensions were reported to correlate significantly to training success. Using the test results from 873 dogs, we estimated heritabilities of, and genetic correlations among, the 38 test items and the 8 underlying behavioral dimensions. Parameters were estimated using a mixed linear animal model including fixed effects of sex, training level, test age and test year-location combination, and random effects of litter, genetic effect of the individual, and residual. Heritabilities ranged from 0.00 to 0.28 (standard error [SE] = 0.05-0.10), which is similar to what has been reported in previous studies of traits defined and measured in a comparable way. Genetic correlations were high (r(g) = 0.92-0.98, SE = 0.08-0.12) between dimensions derived from each rating method and defined as either confidence, engagement, or aggressiveness, but relatively weak among these dimensions within rating method (r(g) = 0.00-0.45, SE = 0.29-0.41). Our results imply that the test measures 3 separate behavioral dimensions and that the SAF temperament test as a whole is possible to use for selection of dogs for breeding, but also that some test items should be measured differently to be meaningful for genetic selection purposes. Furthermore, aggregating variables based on a PCA performed on phenotypic data might be suboptimal when defining dimensions for breeding purposes; taking genetic parameters into consideration resulted in generally higher heritabilities for the dimensions. (C) 2014 Elsevier Inc. All rights reserved.
|
|
| 11. |
- Bengtsson, Christian, et al.
(författare)
-
Mating allocations in Nordic Red Dairy Cattle using genomic information
- 2022
-
Ingår i: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 105, s. 1281-1297
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, we compared mating allocations in Nordic Red Dairy Cattle using genomic information. We used linear programming to optimize different economic scores within each herd, considering genetic level, semen cost, the economic impact of recessive genetic defects, and genetic relationships. We selected 9,841 genotyped females born in Denmark, Finland, or Sweden in 2019 for mating allocations. We used 2 different pedigree relationship coefficients, the first tracing the pedigree 3 generations back from the parents of the potential mating and the second based on all available pedigree information. We used 3 different genomic relationship coefficients, 1 SNP-by-SNP genomic relationship and 2 based on shared genomic segments. We found high correlations (≥0.83) between the pedigree and genomic relationship measures. The mating results showed that it was possible to reduce the different genetic relationships between parents with minimal effect on genetic level. Including the cost of known recessive genetic defects eliminated expression of genetic defects. It was possible to reduce genomic relationships between parents with pedigree measures, but it was best done with genomic measures. Linear programming maximized the economic score for all herds studied within seconds, which means that it is suitable for implementation in mating software to be used by advisors and farmers.
|
|
| 12. |
- Clasen, Julie, et al.
(författare)
-
Conservation of a native dairy cattle breed through terminal crossbreeding with commercial dairy breeds
- 2021
-
Ingår i: Acta Agriculturae Scandinavica, Section A - Animal Science. - : Informa UK Limited. - 0906-4702 .- 1651-1972. ; 70, s. 1-12
-
Tidskriftsartikel (refereegranskat)abstract
- Farmers play a key role in conserving native livestock breeds, but without economic support, farms with native breeds may not be viable. We hypothesized that terminal crossbreeding can improve herd economy and decrease the economic support needed from society. Three scenarios were simulated using SimHerd Crossbred: a herd of purebred Swedish Polled Cattle, a herd of purebred Swedish Red, and a herd of 75% Swedish Polled Cattle and 25% F1 crossbreds. The results showed annual contribution margin per cow in the herd can be increased by euro181 by crossbreeding compared with pure-breeding with the native breed, giving a 13.6% growth in contribution margin. However, the needed cost in subsidies paid by the government will remain unchanged if the population size of the native breed is to be maintained. Combining a crossbreeding strategy with the marketing of niche products may facilitate the conservation of native cattle.
|
|
| 13. |
- Clasen, Julie, et al.
(författare)
-
Dairy cattle farmers' preferences for different breeding tools
- 2021
-
Ingår i: Animal. - : Elsevier BV. - 1751-7311 .- 1751-732X. ; 15
-
Tidskriftsartikel (refereegranskat)abstract
- Breeding technologies play a significant role in improving dairy cattle production. Scientifically proven tools for improved management and genetic gain in dairy herds, such as sexed semen, beef semen, genomic testing, dairy crossbreeding, and multiple ovulation embryo transfer (MOET), are readily available to dairy farmers. However, despite good accessibility, decreasing costs, and continuous development of these tools, their use in Sweden is limited. This study investigated Swedish dairy farmers' preferences for breeding tools through a survey including a discrete choice experiment. The survey was distributed online to 1 521 Swedish farmers and by an open link published through a farming magazine. In total, the study included 204 completed responses. The discrete choice experiment consisted of 10 questions with two alternative combinations, which gave 48 combinations in total. Utility values and part-worth values were computed using a conditional logit model based on the responses in the discrete choice experiment for nine groups of respondents: one group with all respondents, two groups based on respondents using dairy crossbreeding or not within the past 12 months, two based on herd size, two based on respondent age, and two based on whether respondents had used breeding advisory services or not. The strongest preferences in all groups were for using sexed semen and beef semen. Genomic testing was also significantly preferred by all groups of respondents. Except in large herds, MOET on own animals was significantly and relatively strongly disfavoured by all groups. Buying embryos had no significant utility value to any group. Dairy crossbreeding had low and insignificant utility values in the group of all respondents, but it was strongly favoured by the group that had used dairy crossbreeding within the past 12 months, and it was disfavoured by the group that had not. Part-worth values of combined breeding tools showed that combinations of sexed and beef semen, alone or with genomic testing without dairy crossbreeding, were the most preferred tools. Compared with the most common combinations of breeding tools used in the past 12 months, the part-worth values indicated that Swedish dairy farmers may prefer to use breeding tools more than they do today. Statements on the different breeding tools indicated that the respondents agreed with the benefits attributed to the breeding tools, but these benefits may not be worth the cost of genomic testing and the time consumption of MOET. These valuable insights can be used for further development of breeding tools.
|
|
| 14. |
- Clasen, Julie, et al.
(författare)
-
Genetic consequences of terminal crossbreeding, genomic test, sexed semen, and beef semen in dairy herds
- 2021
-
Ingår i: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 104, s. 8062-8075
-
Tidskriftsartikel (refereegranskat)abstract
- The development of breeding tools, such as genomic selection and sexed semen, has progressed rapidly in dairy cattle breeding during the past decades. In combination with beef semen, these tools are adopted increasingly at herd level. Dairy crossbreeding is emerging, but the economic and genetic consequences of combining it with the other breeding tools are relatively unknown. We investigated 5 different sexed semen schemes where 0, 50, and 90% of the heifers; 50% of the heifers + 25% of the first-parity cows; and 90% of the heifers + 45% of the first-parity cows were bred to sexed semen. The 5 schemes were combined in scenarios managing pure-breeding or terminal crossbreeding, including genomic testing of all newborn heifers or no testing, and keeping Swedish Red or Swedish Holstein as an initial breed. Thus, 40 scenarios were simulated, combining 2 stochastic simulation models: SimHerd Crossbred (operational returns) and ADAM (genetic returns). The sum of operational and genetic returns equaled the total economic return. Beef semen was used in all scenarios to limit the surplus of replacement heifers. Terminal crossbreeding implied having a nucleus of purebred females, where some were inseminated with semen of the opposite breed. The F-1 crossbred females were inseminated with beef semen. The reproductive performance played a role in improving the benefit of any of the tools. The most considerable total economic returns were achieved when all 4 breeding tools were combined. For Swedish Holstein, the highest total economic return compared with a pure-breeding scenario, without sexed semen and genomic test, was achieved when 90% sexed semen was used in heifers and 45% sexed semen was used for first-parity cows combined with genomic test and crossbreeding (+(sic)58, 33% crossbreds in the herd). The highest total economic return for Swedish Red compared with a pure-breeding scenario, without sexed semen and genomic test, was achieved when 90% sexed semen was used in heifers combined with genomic test and crossbreeding (+(sic)94, 46% crossbreds in the herd). Terminal crossbreeding resulted in lower genetic returns across the herd compared with the corresponding pure-breeding scenarios but was compensated by a higher operational return.
|
|
| 15. |
- Clasen, Julie, et al.
(författare)
-
Korsning med mjölkkor – effekter på besättningsdynamik och ekonomiskt resultat
- 2020
-
Rapport (populärvet., debatt m.m.)abstract
- I denna simuleringsstudie jämförs besättningsstruktur samt produktionsresultat och ekonomiskt resultat för besättningar med renrasiga kor och besättningar med korsningskor. Vi har använt medeltal från Kokontrollen som ingångsvärden till simuleringsprogrammet SimHerd Crossbred. Holsteinkor (SH), röda kor (SRB) och korsningskor från systematisk slutkorsning (enkelkorsning, terminal cross) ingick i studien. Fyra olika typer av besättningar studerades: bara renrasiga SRBkor, en kärna av renrasiga SRB-kor och SHxSRB-korsningskor, bara renrasiga SH-kor, samt en kärna av renrasiga SH-kor och SRBxSH-korsningskor. Resultaten presenteras både för konventionell och ekologisk produktion, eftersom medeltal för kornas resultat och kostnader och intäkter skiljer sig mellan dessa produktionssystem. Simuleringen visar att det ekonomiska resultatet för mjölkproducenter förbättras när man går från en renrasig besättning till en besättning med korsning och det gäller för såväl konventionell som ekologisk produktion. För besättningar med SRB-kärna blev förbättringen av det ekonomiska resultatet vid övergång till korsning större för ekologisk produktion än för konventionell produktion. Det är kopplat till ett högre avräkningspris för mjölk i ekologisk produktion. Besättningsstrukturen i en besättning med korsning påverkas av djurens reproduktion och funktionella egenskaper. Det medför att utrymmet för korsningskor är större i besättningar med SRB-kärna än i besättningar med SHkärna.
|
|
| 16. |
|
|
| 17. |
- Duchemin, Sandrine, et al.
(författare)
-
Identification of QTL on chromosome 18 associated with non-coagulating milk in Swedish Red cows
- 2016
-
Ingår i: Frontiers in Genetics. - : Frontiers Media SA. - 1664-8021. ; 7
-
Tidskriftsartikel (refereegranskat)abstract
- Non-coagulating (NC) milk, defined as milk not coagulating within 40 min after rennet-addition, can have a negative influence on cheese production. Its prevalence is estimated at 18% in the Swedish Red (SR) cow population. Our study aimed at identifying genomic regions and causal variants associated with NC milk in SR cows, by doing a GWAS using 777k SNP genotypes and using imputed sequences to fine map the most promising genomic region. Phenotypes were available from 382 SR cows belonging to 21 herds in the south of Sweden, from which individual morning milk was sampled. NC milk was treated as a binary trait, receiving a score of one in case of non-coagulation within 40 min. For all 382 SR cows, 777k SNP genotypes were available as well as the combined genotypes of the genetic variants of as1-β-κ-caseins. In addition, whole-genome sequences from the 1000 Bull Genome Consortium (Run 3) were available for 429 animals of 15 different breeds. From these sequences, 33 sequences belonged to SR and Finish Ayrshire bulls with a large impact in the SR cow population. Single-marker analyses were run in ASReml using an animal model. After fitting the casein loci, 14 associations at -Log10(P-value) > 6 identified a promising region located on BTA18. We imputed sequences to the 382 genotyped SR cows using Beagle 4 for half of BTA18, and ran a region-wide association study with imputed sequences. In a seven mega base-pairs region on BTA18, our strongest association with NC milk explained almost 34% of the genetic variation in NC milk. Since it is possible that multiple QTL are in strong LD in this region, 59 haplotypes were built, genetically differentiated by means of a phylogenetic tree, and tested in phenotype-genotype association studies. Haplotype analyses support the existence of one QTL underlying NC milk in SR cows. A candidate gene of interest is the VPS35 gene, for which one of our strongest association is an intron SNP in this gene. The VPS35 gene belongs to the mammary gene sets of pre-parturient and of lactating cows.
|
|
| 18. |
|
|
| 19. |
- Eken Asp, Helena, et al.
(författare)
-
Breed differences in everyday behaviour of dogs
- 2015
-
Ingår i: Applied Animal Behaviour Science. - : Elsevier BV. - 0168-1591 .- 1872-9045. ; 169, s. 69-77
-
Tidskriftsartikel (refereegranskat)abstract
- The domestication of the dog and the ensuing breed creation has resulted in a plethora of dog breeds that differ not only in morphology but also in terms of behaviour. In addition, a majority of the dogs today are no longer utilized for their working ability, but are mainly kept as companion animals. The main aim of this study was to estimate breed differences in everyday behaviour traits, as well as to study the phenotypic correlations between these traits. Dog owners described their dogs' everyday behaviour in a questionnaire. The responses to the questions were combined into 18 behavioural subscale scores (BSS). After editing, the material included dog owner responses for 3591 dogs from 20 different breeds. The breeds represent both working and non-working breeds.We can conclude that breed (and grouping into working vs non-working breeds), age and sex had significant effects on many everyday behaviour traits. The working breeds were about 10% more trainable, showed 30% more interest in playing with humans and were 10-60% less fearful. Furthermore, our results showed that fearful dogs were more aggressive, whereas more social dogs were less fearful and less aggressive. We also found that dogs that were more eager to play with humans were also easier to train. (C) 2015 Elsevier B.V. All rights reserved.
|
|
| 20. |
- Eken Asp, Helena, et al.
(författare)
-
Genetics of Aggression, Fear and Sociability in Everyday Life of Swedish Dogs
- 2014
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Most potential dog owners are looking for a non-aggressive, non-fearful, social and easily trained dog that functions well in everyday life. Despite this, most studies of genetic components for behavior traits have mainly focused on analyzing results from behavior tests and not everyday behavior data. The aim of this study was to estimate genetic parameters for aggression, fear, sociability and trainability in everyday life by using a questionnaire to assess information of the dog's everyday behavior. The genetic analysis included 3128 records distributed over 14 breeds. The effect of breed, sex and age were adjusted for in the estimations of genetic parameters. The estimated heritabilities ranged between 0.08 and 0.38, with the highest heritability found for human-directed play interest. Positive genetic correlations were found between aggression and fear traits. Sociability traits showed a negative genetic correlation with both aggression and fear traits.
|
|
| 21. |
|
|
| 22. |
|
|
| 23. |
- Eriksson, Susanne, et al.
(författare)
-
Genetic trends for fertility, udder health and protein yield in Swedish red cattle estimated with different models
- 2017
-
Ingår i: Journal of Animal Breeding and Genetics. - : Wiley. - 0931-2668 .- 1439-0388. ; 134, s. 308-321
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to estimate and compare genetic trends in Swedish Red cattle using a full multiple-trait (MT) model and trait-group-wise models for female fertility, udder health and protein yield. Field data for maiden heifers from 1989 and cows with a first and second lactation between 1990 and 2007 were included. (Co)variance components were estimated prior to prediction of breeding values. The estimated genetic trends were clearly favourable for protein yield and udder conformation, and in most cases neutral to favourable for clinical mastitis and calving to first insemination. In maiden heifers, the trends were neutral for number of inseminations per service period. Unfavourable genetic trends were estimated for number of inseminations in the first two lactations, but the trends seemed less unfavourable from evaluations within trait groups compared with when using the full MT model. Excluding maiden heifer data affected genetic trends less than using trait-group-wise analyses instead of a full MT model. Unfavourable genetic trends in functional traits may be missed unless the traits are evaluated in a MT model including traits under strong selection.
|
|
| 24. |
|
|
| 25. |
|
|
