Hair Coat Color Research Articles

Design and Synthesis of Clinical Candidate PF-06751979: A Potent, Brain Penetrant, β-Site Amyloid Precursor Protein Cleaving Enzyme 1 (BACE1) Inhibitor Lacking Hypopigmentation.

A major challenge in the development of β-site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitors for the treatment of Alzheimer's disease is the alignment of potency, drug-like properties, and selectivity over related aspartyl proteases such as Cathepsin D (CatD) and BACE2. The potential liabilities of inhibiting BACE2 chronically have only recently begun to emerge as BACE2 impacts the processing of the premelanosome protein (PMEL17) and disrupts melanosome morphology resulting in a depigmentation phenotype. Herein, we describe the identification of clinical candidate PF-06751979 (64), which displays excellent brain penetration, potent in vivo efficacy, and broad selectivity over related aspartyl proteases including BACE2. Chronic dosing of 64 for up to 9 months in dog did not reveal any observation of hair coat color (pigmentation) changes and suggests a key differentiator over current BACE1 inhibitors that are nonselective against BACE2 in later stage clinical development.

English

The study was conducted to characterize meat quality and morphology of sheep in North Shewa Zone, and to generate baseline information on the patency of Menz sheep. A total of 720 sheep were purposely selected for morphological study. The result showed that age at first kidding, age at sexual maturity, weight, height, length, hair length, tail length and age at disposal were with a mean of 5.58 months, 4.55 months, 36.62 kg, 60.44, 82.49 and 4.42 cm and above 1 year, respectively. The result revealed that all sheep in the study areas were local pure breed, most of them were hornless with smooth hair and white coat color traits. The analytical result ranges from 5.68 to 6.25 (pH), 64.06 to 74.18 (moisture), 18.26 to 25.12 (protein), 3.80 to 13.71 (fat) and 1.02 to 1.46 (ash) contents of meat. Menz district sheep showed significant change in the parameters aforementioned. Menz sheep were the best in all traits/parameters, and a need of patent right to improve Menz sheep appropriately is our recommendation. Key words: Meat quality, Menz sheep, morphology.

Analysis of the hair coat of domestic cats with special focus on histological structure

The aim of the study was to characterize the hair coat of domestic cats. The research material consisted of hairs of different fractions collected in winter from female cats with a uniform hair coat colour: white,cream, red, brown and black. The hairs were divided into individual fractions, i.e. underhair, bristle hair and guard hair, and the following characteristics were evaluated: thickness, length, long and short axis length, stress at break and elongation. SEM (scanning electron microscope) images of all types of hair were taken and used to characterize each hair type and to calculate the number of scales per mm of hair length. The content of ions of various chemical elements was determined as well. Underhairs, which accounted for the largest percentage in the coat, were the thinnest and shortest, and had the most regular and distinct scale pattern. Guard hairs were the least numerous, but were the longest and thickest of all hairs examined. Both guard and bristle hairs had irregular scales with jagged edges. The cross-sections of these hairs revealed the presence of all the layers, i.e. the cuticle, cortex and medulla. In the underhair fraction the medulla was observed only in red cats. In all hairs the share of carbon, oxygen and sulphur ions was largest; these are the main omponents of hair protein, i.e. keratin.

The impact of hair coat color on longevity of Holstein cows in the tropics.

BackgroundOver two decades of observations in the field in South East Asia and Hawai‘i suggest that majority of the commercial dairy herds are of black hair coat. Hence a simple study to determine the accuracy of the observation was conducted with two large dairy herds in Hawaii in the mid-1990s.MethodsA retrospective study on longevity of Holstein cattle in the tropics was conducted using DairyComp-305 lactation information coupled with phenotypic evaluation of hair coat color in two large dairy farms. Cows were classified into 3 groups: a) black (B, >90%); b) black/white (BW, 50:50) and c) white (W, >90%). Cows with other hair coat distribution were excluded from the study. In farm A, 211 out of 970 cows were identified having 4 or more lactations. In farm B, 690 out of 1,350 cows were identified with 2 or more lactations for the study.ResultsThe regression analyses and the Wilcoxon-Log-rank test for survival probability showed that Holstein cattle with 90% black hair coat had greater longevity compared to Holstein cattle with 90% white hair coat.ConclusionsThis study suggests that longevity of Holstein cattle in tropical regions was influenced by hair coat color and characteristics.

068 Hair Shedding Score and Hair Coat Color Affect Body Temperature during Heat Stress in Weaned Beef Heifers

068 Hair Shedding Score and Hair Coat Color Affect Body Temperature during Heat Stress in Weaned Beef Heifers

Epistatic interactions between at least three loci determine the "rat-tail" phenotype in cattle.

BackgroundThe “rat-tail” syndrome (RTS) is an inherited hypotrichosis in cattle, which is exclusively expressed in diluted coloured hair. The affected animals also suffer from disturbed thermoregulation, which impairs their health and growth performance. Phenotypic features that are similar to RTS are observed in dogs with black hair follicle dysplasia.ResultsWe used a resource cross population between German Holstein and Charolais cattle breeds to prove that epistatic interactions between at least three independent genetic loci are required for the expression of the RTS phenotype. In this population, the RTS is exclusively expressed in animals with a eumelanic background that is due to the dominant ED allele at the melanocortin 1 receptor gene located on Bos taurus autosome (BTA) 18. In addition, only the individuals that are heterozygous at the dilution locus on BTA5 that corresponds to the premelanosome protein or silver gene variant c.64G>A were classified as displaying a RTS phenotype. Linkage and whole-genome association analyses using different models and different pedigrees allowed us to map a third locus (hereafter referred to as the RTS locus) that is essential for the expression of the RTS phenotype to the chromosomal region between 14 and 22 Mb on BTA5. Our findings clearly demonstrate that the RTS and dilution loci are distinct loci on BTA5.ConclusionsOur study provides evidence that the RTS locus has effects on hair conformation and coat colour dilution and that the effect on coat colour dilution is clearly independent from that of the dilution locus. Finally, our results excluded several other loci that were previously reported to be associated with or to underlie hair conformation or pigmentation traits as the causal mutations of RTS and also several major functional candidate genes that are associated with hypotrichosis in humans. Our finding on the identification of a three-locus interaction that underlies RTS provides a prime example of epistatic interaction between several independent loci that is required for the expression of a distinct phenotype.Electronic supplementary materialThe online version of this article (doi:10.1186/s12711-016-0199-8) contains supplementary material, which is available to authorized users.

Morphological characterization of indigenous sheep in Southern Regional State, Ethiopia

Information on morphological characteristics is a prerequisite to sustainable breed improvement, utilization and conservation. The present study was initiated to describe the physical and morphological characteristics of indigenous sheep reared in Sidama-Gedeo, Kembata Tembaro-Hadiya, Gurage-Silte, Gamogofa and Wolaita zones of Southern Regional State of Ethiopia. Data on the assessment of qualitative characters and linear body measurements were obtained from a total of 3966 sheep that were drawn from 928 households. The results indicated that the most common tail form in the Sidama-Gedeo, Kembata Tembaro-Hadiya, Gurage-Silte and Wolaita sheep was of long fat type ending with a straight tip, whereas that of Gamogofa sheep was long thin tail ending with a curve tip. Hair coat colour pattern was mainly plain followed by patchy. The common hair of sheep in all studied zones was short and smooth. Sheep from Sidama-Gedeo, Kembata Tembaro-Hadiya and Gurage-Silte were devoid of wattle and ruff. Rams of Gurage-Silte and Wolaita had higher (P < 0.05) body weight values than those of other locations. Ewes of Sidama-Gedeo and Wolaita had relatively high (P < 0.05) body weight, whereas those of Gurage-Silte, Gamogofa and Wolaita had significantly high chest girth values. Gurage-Silte and Gamogofa rams had large (P < 0.05) chest girth values. The height at withers was high (P < 0.05) for both sexes in Sidama-Gedeo, Kembata Tembaro-Hadiya and Wolaita sheep. The highest body length was obtained from Wolaita rams, followed by Gamogofa and Kembata Tembaro-Hadiya rams, whereas the lowest body length was obtained from Gurage-Silte rams. Ewes of Sidama-Gedeo had higher (P < 0.05) body length values than those of other zones. The dendrogram indicated a close association among the sheep of Kembata Tembaro-Hadiya, Gurage-Silte and Sidama-Gedeo. However, sheep in Wolaita and Gamogofa were more distantly associated with those of the three zones. It can be concluded that the sheep in the study zones may possess unique adaptive features useful in designing sustainable sheep improvement strategies. However, a molecular-based genetic assessment of the population structure found in the study region might be given due consideration.

Cow-level association between serum 25-hydroxyvitamin D concentration and Mycobacterium avium subspecies paratuberculosis antibody seropositivity: A pilot study

Vitamin D deficiency has been associated with various human diseases. Therefore, the objective of this study was to evaluate the cow-level association between serum 25-hydroxyvitamin D [25(OH)D] concentration and Mycobacterium avium ssp. paratuberculosis (MAP) seropositivity of dairy cows, adjusting for diet, breed, hair coat color, stage of lactation, reproductive status, and cow age. The sera of 80 MAP antibody ELISA-positive and 80 test-negative herd mates from 5 Minnesota dairy herds were analyzed for 25(OH)D and 1,25-dihydroxyvitamin D [1,25(OH)2D]. The cows’ age, production records, and hair coat color were recorded. Additionally, feed samples were obtained and analyzed for vitamin D2 and vitamin D3 content. A linear mixed model was used to identify potential predictors for serum 25(OH)D concentration, accounting for herd of origin. The majority of rations analyzed had over 22,000IU of vitamin D/day (maximum: 52,000IU/d) and the study cows’ average serum 25(OH)D concentration was 62.5±13.8ng/mL. Serum ELISA-positive cows had, on average, 5.3ng/mL lower 25(OH)D serum levels than test-negative herd mates. The reproductive status of cows was also associated with the 25(OH)D levels, with fresh cows having the lowest serum concentration. In this cross-sectional study, a temporal or causal association between MAP antibody ELISA status and serum 25(OH)D concentration could not be evaluated. In addition, the high levels of vitamin D in the rations of participating farms and the average 25(OH)D serum concentration suggest that additional supplementation with vitamin D in the ration is likely to be ineffective.

Comportamento de ovinos da raça Santa Inês, de diferentes pelagens, em pastejo

The objective of this experiment was to evaluate the behavior in Santa Ines sheep, different colorations, under conditions of grazing. The experimental design was completely randomized, with three coat colors (white, brown and black) as treatments and 7 replications in a split plot arrangement with the coat color in the plot and period in the sub-plot. The observations of the variables analyzed were four experimental periods where each period contained three days of behavioral observations. Since the variables: grazing time, rumination time, leisure time, drinking water and other activities The observations were made every 10 minutes from 6 a.m. to 5 p.m. No significant interaction (p > 0.05) between period and color of the coat for any of the behavioral traits studied. The periods affected all behavioral activities. The hair coat color influenced the activity mulling standing at the Sun, the white animals had longer (p

Evaporative cooling and cutaneous surface temperature of Holstein cows in tropical conditions

The effects of skin temperature (T S) on the rate of heat loss by cutaneous evaporation (E S) in Holstein cows chronically exposed to sun, considering hair coat colour were studied. Sixteen purebred cows were measured for E S and T S at 01:00 p.m. after 6 hours of exposure to sun, on three body regions (flank, neck and gluteus) and considering dark and white spots separately. Sweating rate (S) and E S were measured by means of a ventilated capsule. Black skin areas presented mean S (138.9 ± 8.5 gm-2 h-1), E S (93.3 ± 5.7 Wm-2), and T S (33.1 ± 0.2°C) higher than those in the white areas (109.5 ± 9.7 gm-2h-1), 73.6 ± 6.5 Wm-2 and 32.6 ± 0.2°C, respectively). There is an exponential relationship among cutaneous temperature and cutaneous evaporation, which can be represented by the equation: E S = 31.5 + exp{(T S - 27.9)/2.19115}, with coefficient of determination r² = 0.68. Cutaneous evaporative heat loss remains almost constant around 48 Wm-2 until T S reaches nearly 31°C.

Body Temperature and Behavioral Activities of Four Breeds of Heifers in Shade and Full Sun

Four breeds of heifers, eight of each breed, were housed in two types of feedlot pens – one with shade and the other with no shade (exposed to full sun). The breeds were: Black Angus, white Charolais, tan-colored MARC I, and dark-red colored MARC III. The objectives were to determine whether shade made a significant difference in thermal responses (animal activities and vaginal temperature) and to determine the effect of hair-coat color on body temperature due to solar exposure. Providing shade alleviated heat stress by lowering body temperature especially for black Angus and dark-red colored MARC III because of their higher hair-coat color capacity to absorb solar load. These two breeds spent more time standing in shade than the tan-colored MARC I and the white Charolais. The rate of increase of body temperature was higher when the heifers were lying down in full sun (0.61+0.27°C/h) followed by lying down in shade (0.25+0.17°C/h) because of reduced effective surface area to convective evaporative cooling (p<0.05). There was direct linear correlation (R2 ˜ 0.90) between solar absorbing capacity of hair coat and percent of time the heifers spent in shade. The percent of time spent in shade both standing and lying down for each breed was: 89% for Black Angus, 81% for dark-red MARC III, 57% for tan-colored MARC I, and 55% for white Charolais. The study suggested that shade was critical for feedlot cows, especially those with dark hair coat, allowing them to thermally regulate their physiologic needs.

Sweating Rates of Dairy Cows and Beef Heifers in Hot Conditions

Sweating rates from heat-stressed dairy cows and beef heifers were measured using a Portable Calorimeter and a Bovine Evaporation Meter designed and fabricated for the studies reported herein. Measurements were taken when cows were in their natural habitat. The focus of the study was to compare sweating rates measured from different breeds of dairy cows and beef heifers, and determine the level of influence of environmental factors (air temperature, relative humidity, solar load, and air velocity) and hair-coat color on sweating rate. The cows were exposed to solar radiation greater than 500 W/m2 (average 833 132 W/m2), average THI was 82.7 1.64 for all studies except for the Nebraska data where the THI was 77.4 4. Air velocity in the sample area was between 0.8 and 1.2 m/s, and body (rectal) temperature was greater than 38.8C (threshold for heat stress). Sweating rates ranged between 189 84.6 and 522 127.7 g/m2-h. Body temperature ranged between 39.3 0.53C and 41.7 0.19C. Differences in sweating rates were statistically significant at P < 0.05 between breeds, between black and white hair coats, and changes in solar load, relative humidity, and air velocity. Wetting the skin surface and increasing air velocity profoundly increased evaporation rate by converting sensible heat to latent heat.

Hermaphroditism in 3 Chimeric Mice

Hermaphroditism was diagnosed in three, 6-month-old, male, chimeric mice generated by microinjection of 129/Ola XY recombinant embryonic stem cells into unsexed C57BL/6 blastocysts. Grossly, mice Nos. 1 and 2 had perigenital masses and hydrometra. All mice had unilateral ovaries and cystic endometrial hyperplasia. Mice Nos. 1 and 3 also had contralateral testes and epididymides. Histologically, mice Nos. 1 and 3 were true hermaphrodites with unilateral ovotestes, while mouse No. 2 was a pseudohermaphrodite with ovarian tissue only. The presence of a uterus with cystic endometrial hyperplasia in these mice resembles XY pseudohermaphroditism in miniature schnauzers. The mice were determined to be 95 to 100% chimeric via haircoat color; however, the presence of both male and female sex organs in these phenotypically male mice suggests otherwise. Published reports note incidences for sex chimeras and hermaphroditism in genetically engineered mice of 50% and 20%, respectively. Hermaphroditism is expected to increase as the numbers of chimeric mice rise with technical advances in genetic engineering.

Increased prevalence of Borrelia burgdorferi infections in Bernese Mountain Dogs: a possible breed predisposition

BackgroundGlomerulonephritis in dogs has been associated with B. burgdorferi infections. In Bernese Mountain Dogs with glomerulonephritis antibodies against B. burgdorferi have been found in most dogs, raising the question if the breed is predisposed to infections with B. burgdorferi. The aim of this study was to determine the prevalence of antibodies against B. burgdorferi sensu lato in a well defined population of Bernese Mountain Dogs and to compare this prevalence with data from dogs of other breeds.Results160 Bernese Mountain Dogs and 62 control dogs (large breed dogs with long hair) were included. All dogs were considered healthy according to a questionnaire filled out by the owner, complete blood count, chemistry panel, urinalysis and urine culture. Bernese Mountain Dogs and control dogs were kept in similar environments. Seroprevalence of B. burgdorferi was assessed by ELISA and Western blot and was 58% in Bernese Mountain Dogs compared to 15% in control dogs. This difference was significant. Neither antibodies against leptospires nor vaccination or hair coat color influenced the results.ConclusionThe cause of the considerably higher prevalence of antibodies against B. burgdorferi in Bernese Mountain Dogs and it's consequences are not known. A breed predisposition can be suspected.

Coat colour dilution lethal (‘lavender foal a’): syndrome tetany syndrome of Arabian foals

Coat colour dilution lethal (CCDL), referred to as ‘lavender foal syndrome’ by Arabian horse breeders, is a tetany syndrome of newborn Arabian foals of Egyptian breeding. The condition has been recognised for over 50 years but has not been described in the peer-reviewed literature. The purpose of this report is to make practitioners aware of its existence. Aside from the neurological signs, the most striking feature of this condition is the dilute or bleached-out hair coat colour. In a few cases, the colour is a very striking iridescent silver to pale lavender hue, hence the name ‘lavender foal syndrome’. Coat colour dilution lethal is a more appropriate name, as many affected foals do not exhibit the striking lavender colour. Other dilute coat colours observed are pewter (pale slate grey) and pale chestnut (pink).

Um modelo para a determinação do equilíbrio térmico de bovinos em ambientes tropicais

Uma equação com base na teoria da transferência térmica foi apresentada para estimativa da termólise em bovinos expostos a um ambiente tropical especificado por temperatura e umidade do ar, radiação solar e vento. As variáveis do animal (taxa de sudação, temperatura retal, frequência respiratória, temperatura da superfície cutânea, coloração do pelame e peso corporal) foram consideradas em conjunto com as variáveis ambientais (temperatura do ar e umidade, radiação solar, velocidade do vento e temperatura do globo). A equação permite a predição de: (1) o nível de termogênese metabólica necessária para equilibrar as perdas térmicas sob condições ambientais especificadas; (2) a combinação de fatores ambientais que proporcionam determinado fluxo de calor entre um dado animal e o seu ambiente.

Brainstem Auditory‐Evoked Potential Assessment of Congenital Deafness in Dalmatians: Associations With Phenotypic Markers

To screen for congenital deafness, brainstem auditory-evoked potential (BAEP) testing was performed on 1031 Dalmatians from three geographically separated areas. Phenotypic marker assessment was done to determine markers possibly associated with deafness. Markers included sex, hair coat color, pigmentation of different areas of skin (eye rims, nose, and ears), presence of a patch, spot size and marking (density of spotting), sire and dam BAEP status, and presence of iris and retinal tapetal pigmentation. Combined data from all test sites showed 8.1% bilateral deafness (N = 83 dogs) and 21.6% unilateral deafness (N = 223), or an overall 29.7% incidence of hearing disorders. Significant (P less than 0.05) associations with deafness for the data from all test sites combined were seen for patch, sire and dam BAEP, iris pigment, and retinal pigment. However, results differed for several of the significant phenotypic markers when analyses were done on the data from the individual test sites; changes from significant to not significant were found. This suggested the existence of multiple populations of deafness patterns, and reinforced the precautionary conclusion that associations of phenotypic markers with deafness are not necessarily functionally significant.

Veterinary Work in the North-West Frontier Province, India

India possesses vast genetic resources in terms of holding several indigenous breeds of goats. This review highlights the climate resilient potential of various indigenous goat breeds in the Indian sub-continent. Given the fact of goat being projected as ideal climate resilient species, the information in this review could be very useful for the policy makers to propagate ideal breeds to specific agro-ecological zone. With the projected climate change associated fodder deficit, it is very vital to concentrate on sustaining goat production for the various advantages associated with this species. In general, the morphological characteristics of goats that results in higher adaptive and resilient capacity in different climatic zones are body conformation (body size, shape), legs (long), hair coat length (short), hair coat color (light), skin structure (lightly pigmented), sweat glands, subcutaneous fat (less), large surface area, salivary glands, volume and anatomy of the digestive tract. Sirohi, Jakhrana, Jamunapari, Beetal, Gohilwadi, Zalawadi, Kutchi etc are large sized breeds and their long legs helps them to prevent the ground radiation affecting their body and thus imparts them the potential to survive in hot arid and semi-arid tropical environment. On the other hand, goat breeds in Himalayan regions of India namely Assam Hill, Black Bengal, Ganjam, Chegu, Gaddi, Pantja etc are having small sized body and ears, short legs and are naturally adapted to cooler weather conditions. Further, the black coat breeds were found to be more efficient thermo-regulators than white coat breeds. Several biomarkers covering both phenotypic and genotypic traits were suggested to assess the climate resilience in different indigenous breeds of goats. All these basic information could be very useful to identify and propagate ideal goat breeds specific to different agro-ecological zone and such approach may play a significant role in sustaining goat production in the changing climate scenario in India.