Dominant black in cats and its bearing on the question of the tortoiseshell males—A criticism

1927 ◽  
Vol 18 (2) ◽  
pp. 219-221 ◽  
Author(s):  
Ruth C. Bamber ◽  
E. Catherine Herdman
Keyword(s):  
Dominant Black

scholarly journals Traits that influence longevity in mice: a second look.

Genetics ◽  
1992 ◽  
Vol 132 (1) ◽  
pp. 229-239
Author(s):  
K B Dear ◽  
M Salazar ◽  
A L Watson ◽  
R S Gelman ◽  
R Bronson ◽  
...  
Keyword(s):  
Life Span ◽  
Genetic Factors ◽  
Viral Infections ◽  
Genetic Interactions ◽  
Chromosome 9 ◽  
Chromosome 4 ◽  
Histological Findings ◽  
Male And Female ◽  
Female Genotype ◽  
Dominant Black

Abstract Analysis of genetic interactions in the F2 of an intercross of (C57BL/6 x DBA/2) F1J revealed influences of genetic factors on life span. Females lived longer than males. Dilute brown females died sooner than females of other colors. H-2b/H-2b males died sooner than H-2b/H-2d or H-2d/H-2d males, except that among dilute brown males those of typeH-2b/H-2d died sooner. Cluster analysis suggested that male and female genotypes each fall into two groups, with female dilute brown mice having shorter lives than other females, and male H-2b/H-2b mice except dilute brown and dilute brown H-2b/H-2d mice having shorter lives than other males. The association of heterozygosity with life span was clearer in females than in males, yet the longest-lived female genotype was homozygous H-2d/H-2d, of dominant Black phenotype at the Brown locus of chromosome 4, and homozygous dd at the Dilute locus of chromosome 9. The shortest-lived females were dilute brown H-2b/H-2b. The longest-lived and shortest-lived male genotypes were dilute brown H-2d/H-2d and dilute brown H-2b/H-2d, respectively. Although histological findings at postmortem differed between the sexes, there was no association of particular disorders with other genetic markers. The importance of H-2 in males was confirmed, but the allelic effects were perturbed, possibly by the absence of Sendai infection in this experiment. Overall our studies suggest that genetic influences on life span involve interactions between loci, and allelic interactions may change with viral infections or other environmental factors.

Inheritance of different coat colours in Newfoundland dogs in Poland

2019 ◽  
Vol 15 (1) ◽  
pp. 17-28
Author(s):  
Maciej Ziółkowski ◽  
Agnieszka Redlarska ◽  
Katarzyna Adamus-Fiszer ◽  
Joanna Kania-Gierdziewicz
Keyword(s):  
Coat Colour ◽  
The Other ◽  
Black And White ◽  
Dog Breed ◽  
Dominant Black

The aim of the study was to present the manner in which coat colour genes are inherited in the Newfoundland dog breed and to estimate the number of dogs with various coat colours in the Polish Newfoundland dog population in 2017. This population numbered 656 dogs, including 248 males and 408 females. The estimated number of dogs of this breed also included all registered puppies, broken down by gender and coat colour. The genes determining coat colour are described, including more precisely the genes responsible for the coat colour of the Newfoundland breed. According to FCI regulations, the coat colours for Newfoundland dogs are black, brown and black-and-white. Other colours, such as brown-and-white or blue, are not recognized for breeding purposes in Europe. The study found that the dominant black coat was predominant in the Polish Newfoundland dog population in 2017. These dogs could be heterozygous at some other loci and have undesirable alleles. The second most common coat colour was chocolate, while the fewest dogs had spotted coats. The group with spotted coats contained more males than females, in contrast to the other two colour variants. There were also individuals with the blue coat colour, which is not accepted for breeding, as the result of mating of parents with proper coat colours. An understanding of how dog coat colours are inherited and the need for tests to determine coat colour genotypes would make it possible to foresee the occurrence of incorrect colours in subsequent generations, which is crucial for Newfoundland dog breeders, whose goal is to obtain dogs whose coat colour is in line with the FCI standard.

scholarly journals Assessment of long-term production traits of three breeds of exotic commercial layers in the derived Savannah zone of Nigeria

2011 ◽  
Vol 3 (1) ◽  
pp. 20-24
Author(s):  
S. O. Olawumi ◽  
I. Dudusola
Keyword(s):  
Mortality Rate ◽  
Feed Efficiency ◽  
Egg Production ◽  
Production Traits ◽  
Mean Values ◽  
Production Period ◽  
Savannah Zone ◽  
Dominant Black ◽  
Effect Of Age

This study was carried out to compare production traits of three breeds of exotic commercial layers for a production period of 15 months. The breeds are Isa Brown (IB), Bovan Nera (BN) and Dominant Black (DB) and the traits considered are hen-day egg production, feed efficiency and mortality rate. The general means are 5.24eggs/ bird/week, 0.006/bird/week and 0.16/breed/week for egg production, feed efficiency and mortality rate, respectively. There was highly significant (P<0.01) effect of breed on egg production and feed efficiency but the reverse was the case for mortality rate. On egg production, IB genotype recorded 5.37+0.07 eggs/bird/week while BN breed had 5.41+0.08 eggs/bird/week and the values were similar but superior to DB genotype with 4.94eggs/bird/week. For feed efficiency, IB and BN breeds recorded higher mean values and were similar but superior to DB genotype. The mean values are: IB=0.006+9.05x10-5, BN=0.006+8.53x10-5 and DB=0.005/bird/week. Breed’s effect on mortality rate showed that the three genotypes had similar values, that is, breed has no significant (P>0.05) effect on this trait. There was highly significant (P<0.01) effect of age of birds on egg production. Age 2 (2nd month) recorded the highest mean values while age 14 (14th month) was the lowest. The values respectively, are 6.04+0.16 eggs/bird/week and 4.18+0.16 eggs/bird/week. In addition, there was highly significant (P<0.01) effect of age of birds on feedefficiency regardless of the breed of birds. Age 2 (2nd month) recorded the highest mean values and age 14 (14th month) the lowest. There was also highly significant (P<0.01) effect of age on mortality rate of commercial layers. The long-term production analyses showed that IB and BN genotypes are more productive, feed efficient and could be recommended to farmers as commercially viable breeds of layers.

scholarly journals Comprehensive genetic testing combined with citizen science reveals a recently characterized ancient MC1R mutation is associated with partial recessive red phenotypes in dog

2020 ◽  
Author(s):  
Heidi Anderson ◽  
Leena Honkanen ◽  
Päivi Ruotanen ◽  
Julia Mathlin ◽  
Jonas Donner
Keyword(s):  
Citizen Science ◽  
Coat Color ◽  
Allelic Variation ◽  
Wild Type ◽  
Melanocortin 1 Receptor ◽  
Phenotype Analysis ◽  
Genotype Screening ◽  
Dominant Black ◽  
Novel Allele

Abstract Background The Melanocortin 1 Receptor (MC1R) plays a central role in regulation of coat color determination in dogs and is commonly referred to as the “E (extension) Locus”. Allelic variation of the MC1R gene is associated with coat color phenotypes EM (melanistic mask), EG (grizzle/domino) and e1–3 (recessive red) in dogs. In addition, a previous study of archeological dog specimens over 10,000 years of age identified a variant p.R301C in the MC1R gene that may have influenced coat color of early dogs. Results Commercial genotyping of 11,726 dog samples showed the R301C variant of the MC1R gene was present in 34 breeds or breed varieties, at an allele frequency of 1.48% in the tested population. We detected no linkage disequilibrium between R301C and other tested alleles of the E locus. Based on current convention we propose that R301C should be considered a novel allele of the E locus, which we have termed eA for “e ancient”. Phenotype analysis of owner-provided dog pictures reveals eA allele has an impact on coat color and is recessive to wild type E and dominant to the e alleles. In dominant black (KB/*) dogs it can prevent the expression of the K locus, and the expressed coat color is solely determined by the A locus. In the absence of dominant black, eA/eA and eA/e genotypes result in the coat color patterns referred to in their respective breed communities as domino in Alaskan Malamute and other Spitz breeds, grizzle in Chihuahua, and pied in Beagle. Conclusions This study demonstrates a large genotype screening effort to identify the frequency and distribution of the MC1R R301C variant, one of the earliest mutations captured by canine domestication, and citizen science empowered characterization of its impact on coat color.

scholarly journals Melanocortin Receptor 1 (MC1R) Mutations and Coat Color in Pigs

Genetics ◽  
1998 ◽  
Vol 150 (3) ◽  
pp. 1177-1185 ◽  
Author(s):  
J M H Kijas ◽  
R Wales ◽  
A Törnsten ◽  
P Chardon ◽  
M Moller ◽  
...  
Keyword(s):  
Coat Color ◽  
Melanocortin Receptor ◽  
Missense Mutations ◽  
Wild Type ◽  
Black Spots ◽  
European Wild Boar ◽  
Classical Extension ◽  
Strong Candidate ◽  
Dominant Black ◽  
Black Color

Abstract The melanocortin receptor 1 (MC1R) plays a central role in regulation of eumelanin (black/brown) and phaeomelanin (red/yellow) synthesis within the mammalian melanocyte and is encoded by the classical Extension (E) coat color locus. Sequence analysis of MC1R from seven porcine breeds revealed a total of four allelic variants corresponding to five different E alleles. The European wild boar possessed a unique MC1R allele that we believe is required for the expression of a wild-type coat color. Two different MC1R alleles were associated with the dominant black color in pigs. MC1R*2 was found in European Large Black and Chinese Meishan pigs and exhibited two missense mutations compared with the wild-type sequence. Comparative data strongly suggest that one of these, L99P, may form a constitutively active receptor. MC1R*3 was associated with the black color in the Hampshire breed and involved a single missense mutation D121N. This same MC1R variant was also associated with EP, which results in black spots on a white or red background. Two different missense mutations were identified in recessive red (e/e) animals. One of these, A240T, occurs at a highly conserved position, making it a strong candidate for disruption of receptor function.

Productive and Physiological Responses of Heat-Stressed Dominant Black Hens to Artificial Ventilation and Modified Layers Mash in Nigeria

2015 ◽  
Vol 14 (8) ◽  
pp. 471-478
Author(s):  
O.G. Fasanmi ◽  
O.J. Okuneye ◽  
E.S. Ajibola ◽  
M.O. Oladele- Bukola ◽  
J.F. Olona ◽  
...  
Keyword(s):  
Artificial Ventilation ◽  
Physiological Responses ◽  
Dominant Black

Who Discovered the Dominant Black Rabbit?

1939 ◽  
Vol 30 (5) ◽  
pp. 210-210
Author(s):  
E. C. RICHARDSON
Keyword(s):  
Dominant Black
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