Hair Coat Color Research Articles

275 Frequency of chronic passive congestive livers at harvest in the Texas Panhandle and the association with carcass outcomes

Abstract Chronic passive congestive (CPC) livers are reported as one of the most common clinical signs of right-sided Bovine Congestive Heart Failure (BCHF). Frequency of CPC livers at harvest and the associated loss of offal and carcass value does not appear in the literature. Our objectives were to 1) quantify the frequency of CPC livers at harvest within the Texas Panhandle, and 2) evaluate the association with offal and carcass outcomes. Audits were performed over the duration of a production week (both harvest shifts) per each large commercial beef processing facility (4 total) in the Texas Panhandle. West Texas A&M University trained personnel identified CPC (large blue) livers at evisceration and documented heart score (HS; scale 1 = normal to 5 = extreme structural changes), liver weight, USDA-FSIS inspection fate (U.S. Inspected & Passed; U.S. Condemned) of the liver, remaining viscera, and carcass. Other visual observations (sex, predominant black hair coat color, carcass/visceral edema, liver abscesses) were noted. 1) Frequency data were documented among cattle-type populations: sex (steers, heifers, cows, bulls), and phenotype [native, dairy-cross, dairy, category-B (Mexico-origin)]. 2) Carcass and lot identification were collected for the purpose of tracking and obtaining carcass grading data. Of carcasses deemed wholesome-U.S. Inspected & Passed, USDA yield and quality metrics [hot carcass weight (HCW), 12th-rib fat thickness (FT), ribeye area (REA), marbling score (MS)] of those identified with CPC, as well as data for the balance of respective lots were collected. Carcass outcomes of those exhibiting a CPC liver were compared with the outcomes of remaining lot. Frequency data were analyzed via chi-square. Carcass data were analyzed using mixed models, where occurrence of CPC liver was the fixed effect; facility, cattle type, and sex were random effects. A total of 83,527 animals were audited, with a CPC liver frequency of 0.17% (n = 144). Frequencies among sex (steer = 0.16%; heifer = 0.17%; cow = 0.33%; P < 0.01) and phenotypes (native = 0.15%; category-B = 0.04%; dairy cross = 0.14%; P = 0.01) were documented. Heart scores ranged from 1 to 4, with HS 3 occurring most frequently [HS 1 (n = 2); HS 2 (n = 39); HS 3 (n = 62); HS 4 (n = 17)]. Weights of CPC livers ranged from 7.3 kg to 34.4 kg; the heaviest CPC livers were recorded in cows (mean = 17.2 kg; P < 0.01). Despite USDA-FSIS guidelines, 2.08% of CPC livers were U.S. Inspected & Passed, along with 16.90% of viscera and 84.03% of carcasses. Cow carcasses encountered the greatest U.S. Condemn-rates (38.24%) among the sex categories. Within the fed-beef population, natives were the only category resulting in U.S. Condemned carcasses (10.64%). All carcass outcomes were decreased (P ≤ 0.01) by CPC livers.

82 Effects of a red-clover containing mineral on heifer behavior and fertility

Abstract Heat stress reduces reproductive efficiency in beef cattle. Recent evidence suggests that supplementation of red clover can alleviate the physiological impacts of fescue toxicosis which could decrease heat stress. Our objective was to determine the effect of supplementing heifers grazing endophyte-infected tall fescue (E+ TF) with a conventional mineral containing red-clover leaf. We hypothesized that heifers supplemented with the red-clover leaf mineral would have greater conception rates to AI (CRAI) in times of possible heat stress compared with heifers supplemented with conventional mineral. A grazing study was conducted from May – August in 2021, 2022, and 2023. Yearling beef heifers (n = 32, 36, 40 heifers yr-1, respectively) were blocked by body weight, hair coat score and color into 4 grazing blocks that were assigned to 1 of 2 treatments (2 blocks treatment-1): 1. conventional non-medicated loose mineral control (0%-RC), or 2. conventional loose mineral + 20% wt/wt red clover leaf (20%-RC). Mineral treatments were provided in ground, 3-compartment mineral feeders ad libitum. Each grazing block was assigned to four, 0.8- ha. pastures consisting of predominantly E+ TF and were rotationally managed over the course of the study. Each year estrus was synchronized suitable for fixed time AI in May and all heifers resynchronized in June. In addition, each heifer was fitted with an ear-tag sensor (CowManager SensOor, Agis Automatisering BV, Harmelen, the Netherlands) for continuous behavioral monitoring (including high activity and activity). The CRAI were analyzed with the GLIMMIX procedure of SAS using the binomial distribution link logit function (v.9.4., SAS Inst. Inc., Cary, NC). Total daily activity and high activity reported by CowManger during May and June were analyzed by the MIXED procedure with repeated measures of SAS. The CRAI were similar for 20%-RC (67.30 ± 9.80%) and 0%-RC (60.70 ± 9.80%) heifers following the first service of AI (P = 0.51) during a thermoneutral period in May. In contrast, CRAI was greater (P = 0.02) for 20%-RC heifers (48.67 ± 13.47%) than CM (15.10 ± 13.47%) in June when temperatures increased to potential heat stress levels. Overall, conception rate after two rounds of AI for 20%-RC (78.30 ± 9.30%) heifers tended to be greater (P = 0.08) than CM (62.20 ± 9.30 %). While high activity (associated with estrous behavior) reported by CowManager did not differ between treatments (20%-RC: 203.94; 0%-RC: 213.90; SEM: 8.65 min d-1; P = 0.25), normal daily activity of 20%-RC heifers (150.69 ± 10.40 min d-1) tended to be greater (P = 0.06) than CM (126.33 ± 8.65 min d-1). Results of this study suggest supplementing red-clover containing mineral may mitigate negative effects of consuming E+ TF including decreased conception rates during times of heat stress.

197 Trace Mineral Source Affects Haircoat Characteristics and Shedding in Cats

Abstract Trace minerals have a pivotal role in maintaining skin health and haircoat characteristics in companion animals. The objective of the current study was to evaluate the effects of inorganic versus amino acid complexed sources of trace minerals on feline skin and haircoat characteristics as well as hair growth. A total of 40 cats (age 5 – 12 years; 22 female, 18 male) were used in this 105-d (15-d acclimation; 90-d test period) trial at Summit Ridge Farms (Susquehanna, PA) from January to April 2022. All cats were fed a basal diet that contained sulfate sources of trace minerals formulated to meet AAFCO (2021) recommendations for 15 d before being randomly assigned (blocked by haircoat color, age, sex, and weight) to 1 of 2 treatments. Dietary treatments included sulfate sources (CON; n = 20) and amino acid complexed (Zinpro ProPath, Zinpro Corp. Eden Prairie, MN) sources (ZPM; n = 20) of supplemental trace minerals. Both treatments were formulated to provide equal amounts of supplemental trace minerals (DM basis), differing only in source (100 ppm Zn, 15 ppm Mn, 12 ppm Cu, 80 ppm Fe). On d 15, a side patch was shaved just below the back (3” x 4”) to evaluate hair growth on d 60 and 105 (average of 3 measurements). Additionally, visual haircoat evaluations and shed hair amount were evaluated at d 60 and 105. All research personnel were blinded to treatments. Statistical analyses were completed using GLIMMIX procedure of SAS 9.4 with d 15 as a covariate and cat as the experimental unit. Trace mineral source did not affect body condition score at either time point. There was no treatment or treatment x day interaction for hair length. A trend (p = 0.13) for a 3-way interaction between treatment, sex, and day was detected due to male cats having longer hair at d 105. Shed hair was evaluated by brushing (20 strokes) and weighing collected hair. No overall treatment effect was detected for shed hair; although, a treatment x day interaction (P = 0.02) for shed hair was observed. At d 60, ZPM cats had 23 mg less shed hair compared with CON cats (P = 0.08). Haircoat scores for shine, scale, and overall quality were assessed by a veterinarian. There were no treatment or treatment x day interactions for shine or overall scores. A treatment x day interaction was detected (P = 0.02) for scale (dander). At d 60, ZPM cats had a reduced average scale score compared with CON cats (0.66 vs 1.05, respectively; P = 0.03). Overall, our data suggests trace mineral source may influence shed hair amount and dander production in cats. Further research to evaluate the influence of season and sex is warranted.

62 The Impact of Hair Coat Color on Body Temperature in Beef Cattle

Abstract Ambient temperature has a fundamental role in animal health and performance. Selecting for coat color may improve animal productivity and welfare through management and breeding decisions. The thermoneutral zone of cattle, 0°C - 25°C, is characterized as the range in ambient temperature that does not require cattle to expend energy to maintain core body temperature. When the ambient temperature is above or below these values, cattle must expend energy to keep their body temperature in homeostasis resulting in a reduction in efficiency. A proper herd management plan to mitigate heat stress can increase efficiency and decrease mortality in serious cases. Registered Hereford and commercial black cows (n = 39; average 4 yr of age) were placed in a 23-ha pasture, to determine if coat color affects internal body temperature. Cattle were on a typical fescue dominated pasture located in Mountain Grove, MO, with areas of shade and one pond centralized in the pasture. Cattle were divided into treatments based on hair coat color: black (n =13) or red (n = 26). Using temperature data loggers, vaginal temperatures were recorded in 5-min intervals during a 14-d period in Mid-July 2022, and combined into 6-hour timing intervals, A = 0400-1000 h, B = 1001-1600 h, C = 1601-2200 h, and D = 2201-0359 h. Environmental temperature data loggers were suspended in two locations of partial sun to record ambient temperature. In addition, the Mountain Grove weather station operated by the University of Missouri Extension provided a daily data archive that recorded wind speed, total precipitation, maximum and minimum air temperature. Throughout the study, the mean environmental temperature was 34.4°C and ranged from 19.5°C to 40.2°C. Temperature data were evaluated using the Glimmix procedure of SAS and pairwise comparisons between timepoints were determined utilizing the GLM procedure of SAS. Differences were considered significant at P = 0.05. Black-haired cattle were warmer at all intervals (P ≤ 0.04) with temperature differences between the treatments of 0.07, 0.10, 0.03, and 0.09°C for timepoints A, B, C and D, respectively (Table 1). Based on our results black-hided cattle get warmer earlier in the day and take longer to dissipate heat than those with red hair coats.

Methods, Thermodynamic Applications, and Habitat Implications of Physical and Spectral Properties of Hair and Haircoats in Cattle.

The physical properties (hair diameter, hair length, haircoat depth and haircoat density) and spectral properties (absorptivity, reflectivity, transmissivity) of the hair and haircoat of cattle are inputs to heat and moisture exchange between the skin surface and the surrounding environment, and thus play a critical role in body temperature regulation. Physical and spectral properties of haircoats also play an important role in protecting the skin against penetration of ultraviolet radiation. The focus of this review is to identify accurate and consistent measurement procedures of these properties. Additionally, the paper shows the utilization of the properties on heat exchange models and their implications on voluntary thermoregulation of cattle. To highlight the effects and benefits of haircoat color vis-à-vis solar radiation and its implication on ecological habitation, a brief explanation is provided using polar bears (white haircoat in a cold environment) and black goats in a hot desert environment.

Holstein heifers in desert climate: effect of coat color on physiological variables and prediction of rectal temperature.

Two hundred Holstein heifers were divided by hair coat color in black (n1 = 60), white (n2 = 62), and mixed (n3 = 78) to accomplish two objectives: (1) to compare physiological variables using an analysis of variance, and (2) to construct regression equations to predict rectal temperature. In each heifer, rectal temperature (RT), respiration frequency (RF), and body surface temperatures (obtained with infrared thermography in eye, nose, forehead, head, neck, ear, shoulder, flank, belly, leg, loin, rump, and vulva) were measured. Black heifers had more RF and RT (P < 0.01) than mixed and white coat heifers; white heifers had similar RT than mixed color heifers, but they exhibited less RF (P < 0.05). In general, black and mixed coat color heifers had higher BST (P < 0.01) than white heifers in the majority of the anatomical regions measured. For black coat heifers, the best regression model to predict RT included three predictor variables: [RT = 35.59 - 0.013 (RH) + 0.045 (RF) + 0.019 (TEar); R2 = 71%]. For white coat heifers, the best model included two predictor variables: [RT = 35.29 + 0.035 (RF) + 0.033 (TForehead); R2 = 71%]; and for mixed coat color heifers, the best model included two predictor variables: [RT = 35.07 + 0.022 (RF) + 0.038 (THead); R2 = 44%]. Heifers with dark hair coat color showed higher physiological constants than white heifers; the prediction of rectal temperature was more precise in heifers with well-defined hair coat color. Physiological and climatic variables, along with infrared thermography, represent an appropriate combination to predict rectal temperature in Holstein heifers with predominant white or black hair coat color.

Evaluating the Histologic Grade of Digital Squamous Cell Carcinomas in Dogs and Copy Number Variation of KIT Ligand—A Correlation Study

Dark-haired dogs are predisposed to the development of digital squamous cell carcinoma (DSCC). This may potentially suggest an underlying genetic predisposition not yet completely elucidated. Some authors have suggested a potential correlation between the number of copies KIT Ligand (KITLG) and the predisposition of dogs to DSCC, containing a higher number of copies in those affected by the neoplasm. In this study, the aim was to evaluate a potential correlation between the number of copies of the KITLG and the histological grade of malignancy in dogs with DSCC. For this, 72 paraffin-embedded DSCCs with paired whole blood samples of 70 different dogs were included and grouped according to their haircoat color as follow: Group 0/unknown haircoat color (n = 11); Group 1.a/black non-Schnauzers (n = 15); group 1.b/black Schnauzers (n = 33); group 1.c/black and tan dogs (n = 7); group 2/tan animals (n = 4). The DSCCs were histologically graded. Additionally, KITLG Copy Number Variation (CNV) was determined by ddPCR. A significant correlation was observed between KITLG copy number and the histological grade and score value. This finding may suggest a possible factor for the development of canine DSCC, thus potentially having an impact on personalized veterinary oncological strategies and breeding programs.

Traditional, breeding objectives and selection criteria of Arsi-bale goats reared at different Agro ecologies of bale zone, Ethiopia

Background and objectives: This study was carried out to access the indigenous knowledge pertaining to the selection criteria and breeding objectives of Arsi-Bale goats reared under different agro ecologies of Bale zone, Oromia Region, Ethiopia. Thus, the study indicated that long-haired goats are reared only at highlands with a few being reared at the midlands. Most of the goats in the midlands were short coated. In the high lands the does were selected based on their coat type (long hair and glossy) coat color(black),.While at the midlands the does were selected based on their reproduction rate, kidding interval for does and reproduction rate followed by body conformation were preferred trait of buck for the mid land. While in the low land they preferred does and buck for their body conformation, hair coat type(White).Bucks were reared at Highland for cash income, skin (saddle) and wealth. At mid-lands they were kept for meat, cash and manure while in the case of Low land Bucks are for cash and meat. The selection criteria of buck and does in High land included their adaptability to high altitude conditions besides black coat color and high body weight and does in Highland include long hair, large body and coat color (black).respectively. However, in Mid-Land does and bucks were selected based on higher body weight and with large body size followed by good mothering ability. Materials and methods: The study was conducted in three Woredas of Bale zone Oromiya (Highland, Mid-Land, Low land) National Regional State. Bale zone has a latitude and longitude of 7°7′N 40°0′E with an elevation of 2,492 meters (8,176 ft) above sea level. Sampling methodology: The weredas in the zone was selected based on purposive sampling method. The woredas i,e highlands (Dinsho),midlands (Agarfa) and lowlands (Ginnir)were selected based on the agro ecologies, goat population within the agro ecology. 135 respondents were identified purposively based on their experience in rearing goats, besides their willingness to participate in the project. Statistical analysis: The data was analyzed using Statistical Package for Social Sciences SPSS (V24) of Windows. The data was divided into both quantitative and qualitative parameters. The quantitative traits were analyzed using descriptive statistics the means(inferential eta ANOVA) were compared across the three agro ecologies using Duncan’s multiple Range test, while the qualitative traits were assessed using non parametric tests ( viz. chi square test). Results: The preferred traits of does reared at different agro ecology of Bale Zone in the highlands indicate selection based on coat color of the goats were preferred the most over the other traits. The findings indicate that bucks are primordially reared for cash income. At midlands and lowlands the bucks are also reared for wealth and manure. Conclusion: It can be concluded that goat selection criteria and breeding objective at different agro ecology are different. Most goat selection criteria was coat color and the main objective was for cash income, wealth and manure.

Prevalence of Echocardiographic Evidence of Trace Mitral and Aortic Valve Regurgitation in 50 Clinically Healthy, Young Adult Labrador Retrievers without Heart Murmur.

Background-Though physiologic regurgitation of the right-sided cardiac valves is well recognized in dogs and other mammals, the prevalence of trace insufficiency of the mitral and aortic valves in clinically healthy, young adult dogs is unknown. Methods-In this observational cross-sectional study, 50 clinically healthy, young adult Labrador retrievers without an audible heart murmur were enrolled. All dogs were bred and owned by a single organization. Cardiac screening was requested for all dogs that were intended for breeding. These dogs underwent a cardiac auscultation and transthoracic echocardiography by a veterinary cardiology specialist. If mitral or aortic valve regurgitation was noticed, the jet size was subjectively assessed on color Doppler echocardiography. Pedigree analysis was performed to reveal a possible hereditary background of mitral valve regurgitation. Results-The prevalence of trivial mitral valve regurgitation was 52% with no significant predisposition to gender (p = 0.86) or haircoat color (p = 0.68). The prevalence of aortic valve regurgitation was 4%. Pedigree analysis for mitral valve regurgitation showed familial clustering, suggesting a hereditary background of the trait. Conclusions-The prevalence of silent trace mitral valve regurgitation in young adult Labrador retrievers was high. Because the regurgitant jet was trivial in all dogs, it is probably physiologic.

Exterior characteristics and body measurements of Bligon goat on the different agro-ecological zones in Bantul District, Yogyakarta, Indonesia

Abstract. Rahmawati RD, Atmoko BA, Budisatria IGS, Ngadiyono N, Panjono. 2021. Exterior characteristics and body measurements of Bligon goat on the different agro-ecological zones in Bantul District, Yogyakarta, Indonesia. Biodiversitas 23: 143-150. The Bligon goat is one of the goat breeds those farmers mostly keep in Bantul District, Yogyakarta, Indonesia. This study was conducted to determine the exterior characteristics of Bligon goat in different agro-ecological zones in Bantul District. A total of 478 Bligon goats taken from highlands (146 head), lowlands (163 head), and coastal (169 head) were observed and grouped by age (0-6 months), young (6-18 months), and adults (&gt;18 months). The data observed included qualitative traits (body color distribution and ear shape) and quantitative traits (withers height, chest girth, body length, ear length, and body weight). Qualitative data were analyzed descriptively, and quantitative data were analyzed using one-way analysis of variance. The results showed that the head hair coat color of Bligon goats was mostly striped (pied), with the percentages in the highland, lowland, and coastal zones being 71.9%, 69.2%, and 67.7%, respectively. The body hair coat color in the highland (52.1%) and lowland (39.6%) were striped primarily, while on the coast, it was white (70.7%). The crest color in the highland (69.9%) and lowland (44.7%) were mostly a mixture of brown, black, and white, while on the coast, it was white (70.1%). The mane ruff (rewos) color in the highland (88.4%), lowland (57.9%), and coast (59.3%) were primarily a mixture of brown, black, and white. Ear shapes in the highland (92.5%) and lowland (73.6%) are open principally, while in the coastal areas are mostly folded (56.9%). The average body size of Bligon goats in the coastal zone was larger than in the lowlands (P&lt;0.05), and in the lowlands was larger than in the highlands (P&lt;0.05). It was concluded that the different agro-ecological zones in Bantul District have different exterior characteristics in Bligon goats both qualitatively and quantitatively.

Study on effect of hair coat color on various reproductive attributes of Cholistani service bulls

The objective of the present study was to assess the possible effect of hair coat color on various orchidometric, seminal and andrological attributes of black-coated and brown-coated Cholistani service bulls. Adult Cholistani bulls (n= 8) were grouped as black-spotted (n= 4) and brown-spotted (n=4). Semen collection was performed once weekly (2 ejaculates/collection) using artificial vagina (AV) throughout the study period (October-May). Semen samples were evaluated for various physical attributes. Body weight and orchidometric attributes of the bulls were attained using calipers. Blood sampling was performed twice weekly and serum testosterone level was deduced through automated analyzer. The scrotal circumference, Scrotal Skin Fold Thickness and Paired Testicular Volume were significantly higher (P&lt;0.05) in black-spotted Cholistani bulls as compared to brown-spotted bulls. Similarly, the ejaculatory volume (5.8±0.1 mL) and individual sperm motility (63.3±1.4%) were significantly higher (P&lt;0.05) in black-spotted bulls. Percentage of live spermatozoa, and spermatozoa with normal morphology and acrosome was also higher in black-spotted bulls though statistically non-significant (P&gt;0.05). Amongst post-thaw seminal attributes, percentage of live spermatozoa, and spermatozoa with normal morphology and acrosome were significantly higher (P&lt;0.05) in black-spotted bulls. Similarly, serum testosterone level in black-spotted Cholistani bulls (6.9±0.3 ng/mL) was significantly higher (P&lt;0.05) compared to brown-spotted bulls (5.4±0.3 ng/mL). The black-spotted Cholistani service bulls showed substantially better orchidometric and seminal attributes allied with higher serum level of testosterone.

MORPHO-PHYSIOLOGICAL RESPONSES OF BOS INDICUS, BOS TAURUS AND CROSSBRED WEANED HEIFERS TO SEASONAL VARIATIONS

Animals kept in extensive production systems are constantly exposed to the effects of climatic aspects, which could favour thermal discomfort, decreasing productive and reproductive performances. Utilisation of Bos taurus crosses with Bos indicus animals is increasing in the tropics aimed at improving production and it is now well known how these animals respond in such environment. The objective was to characterize the morpho-physiological thermoregulation responses of weaned heifers from four different genetic groups to infer regarding the different degrees of adaptation to heat under tropical conditions Forty-eight, pasture-kept, 6-month-old, weaned heifers from four distinct genetic groups: (1) Nellore; (2) Senepol; (3) Angus x Nellore; and, (4) ¼ Brahman x ¼ Nellore x ½ Senepol (Tri-cross) were evaluated. Skin, hair coat and rectal temperatures; sweating rate; respiratory and heart rates; visual analysis of hair and hair coat colour; hair coat temperature and thickness; and length, diameter, density and number of hairs were evaluated. In addition, the temperature-humidity index, black-globe temperature and humidity index, and radiant thermal load were determined. Angus x Nellore animals presented the lowest (P=0.008) respiratory rate. Rectal temperature did differ (P=0.001) between seasons. Angus x Nellore heifers showed the greatest (P=0.001) values for the morphological measures in the evaluated months, coinciding with thermal comfort indexes above those considered comfortable for cattle. Nellore (Bos indicus), Brahman x Nellore x Senepol, and Senepol (B. taurus) present the best adaptive traits in savanna. The utilisation of B. indicus animals or adapted breed confers desirable morphological characteristics for the tropical environment.

White hair coat color does not influence heat tolerance of sheep grazing under a hot arid environment

High climatic temperature is the most important factor hampering livestock productivity in tropical and arid regions. Therefore, the current study aimed to investigate the interaction between coat color and heat tolerance in two principal Saudi sheep breeds; Najdi (black colored coat) and Naemi (white colored coat). Najdi and Naemi adult sheep of different age groups and both sexes, raised under direct solar radiation in different parts of the Riyadh region were used. The thermo-physiological measurements were taken from sheep flocks raised under a similar production system in different parts of Riyadh region during the summer season. The recorded rectal temperature (Tre) was significantly (P < 0.05) higher in the white coat colored breed compared to the black coat colored breed. Consequently, the calculated heat tolerance coefficient (HTC) was significantly (P < 0.05) higher in the black coat colored breed compared to the white coat colored one. No significant (P> 0.05) differences were observed concerning skin temperature (Tsk), packed cell volume (PCV) and plasma albumin levels between the two breeds. The obtained results indicate that white coat color of sheep grazing under a hot arid climate is not a crucial trait of heat tolerance and adaptation. Other hair coat characteristics and evaporative cooling traits might play important role in the adaptation of the black coat colored sheep breed grazing under hot arid conditions.

Variants at the ASIP locus contribute to coat color darkening in Nellore cattle

BackgroundNellore cattle (Bos indicus) are well-known for their adaptation to warm and humid environments. Hair length and coat color may impact heat tolerance. The Nellore breed has been strongly selected for white coat, but bulls generally exhibit darker hair ranging from light grey to black on the head, neck, hump, and knees. Given the potential contribution of coat color variation to the adaptation of cattle populations to tropical and sub-tropical environments, our aim was to map positional and functional candidate genetic variants associated with darkness of hair coat (DHC) in Nellore bulls.ResultsWe performed a genome-wide association study (GWAS) for DHC using data from 432 Nellore bulls that were genotyped for more than 777 k single nucleotide polymorphism (SNP) markers. A single major association signal was detected in the vicinity of the agouti signaling protein gene (ASIP). The analysis of whole-genome sequence (WGS) data from 21 bulls revealed functional variants that are associated with DHC, including a structural rearrangement involving ASIP (ASIP-SV1). We further characterized this structural variant using Oxford Nanopore sequencing data from 13 Australian Brahman heifers, which share ancestry with Nellore cattle; we found that this variant originates from a 1155-bp deletion followed by an insertion of a transposable element of more than 150 bp that may impact the recruitment of ASIP non-coding exons.ConclusionsOur results indicate that the variant ASIP sequence causes darker coat pigmentation on specific parts of the body, most likely through a decreased expression of ASIP and consequently an increased production of eumelanin.

Influence of season and external morphology on thermal comfort and physiological responses in bulls from two breeds adapted to a subtropical climate

ABSTRACT Animals in subtropical regions can be exposed to periods of thermal stress. Locally adapted breeds are especially important in this context, but these have little information available in their natural environments. The aim of this study was to assess whether season affects thermal comfort and physiological responses to increased temperatures of two breeds of bulls in a subtropical climate. Four Angus and four Crioulo Lageano bulls were used in this study. Body and testicles measurements, skin pigmentation and thickness, hair number, length and pigmentation, respiratory rate, panting score, rectal temperature and haematological profile were recorded on three occasions in summer and winter, morning and afternoon. The surface temperature of the flank, eye and scrotum were obtained by infrared thermography. Hair coat colour was determined by CIELAB method. Thermal comfort indexes were calculated from meteorological data. Statistical analysis included analyses of variance, correlations and a partial least squares regression in determining which traits were the most important in thermal adaptability. External morphology of the bulls was important for explaining physiological changes in both seasons, but their contribution was greater in summer. Bulls experienced moderate heat stress in summer, which led to significant physiological responses, which were more pronounced in Angus bulls. The main differences in thermal adaptation found between breeds were the hair coat characteristics and respiratory rate. Despite using different mechanisms to cope with environmental challenges, all bulls were able to maintain optimal testicular thermoregulation as well as systemic normothermia throughout the seasons, showing good adaptation to the climate conditions.

Evaluating the Histologic Grade of Digital Squamous Cell Carcinomas in Dogs with Dark and Light Haircoat—A Comparative Study of the Invasive Front and Tumor Cell Budding Systems

Simple SummaryThis study compares two different adapted grading systems for Canine digital squamous cells carcinomas, taking into account the animals’ haircoat color and focusing on the tumor’s invasive front. In general, dark-haired breeds develop more poorly differentiated DSCC than their light-haired counterparts. Additionally, both grading systems challenged are in agreement when grading well differentiated CDSCC in both populations but are discordant when assessing tumors with poorly differentiated features. To our knowledge, this is the first study comparing CDSCC in dogs by two histological grading systems, taking into account their phenotypical and presumed genotypical haircoat color and demonstrating that digital squamous carcinomas are not only more common in dark-haired dogs, but potentially more aggressive.Canine digital squamous cell carcinomas (CDSCC) are particularly aggressive when compared to their occurrence in other locations. Although these neoplasms are more frequently seen in dark-haired dogs, such as Giant Schnauzers, there are no data checking whether these tumors are histologically different between breeds. We histologically evaluated DSCC from 94 dogs. These were divided into two groups, namely, (1) dark-haired (N = 76) and (2) light-haired breeds (N = 18), further subdividing Group 1 into three subgroups, (1a) black breeds (n = 11), (1b) Schnauzers (n = 34) and (1c) black & tan breeds (n = 31). Adaptations from two different squamous cell carcinomas grading schemes from human and veterinary literature were used. Both systems showed significant differences when compared to Groups 1 and 2 in terms of final grade, invasive front keratinization, degree of invasion, nuclear pleomorphism, tumor cell budding, smallest tumor nest size and amount of tumor stroma. Group 2 was consistently better differentiated CDSCC than Group 1. However, there were no significant differences among the dark-haired breeds in any of the features evaluated. This study represents the first attempt to grade CDSCC while taking into account both phenotypical and presumptive genotypical haircoat color. In conclusion, CDSCC are not only more common in dark-haired dogs, they are also histologically more aggressive.

Serological evidence of co-circulation of West Nile and Usutu viruses in equids from western Spain.

West Nile virus (WNV) is a mosquito-borne emerging virus in Europe with capacity to cause neurological complications such as encephalitis or meningoencephalitis in humans, birds or equids. In Spain, WNV is actively circulating in mosquitoes, birds and horses in different regions, but never has been deeply studied in Extremadura. Therefore, the aim of this study was to evaluate the seroprevalence of WNV in equids of those areas and to analyse the risk factors associated with exposure to the virus. A total of 199 out of 725 equids presented antibodies against WNV by competition ELISA (27.45%), while 22 were doubtful (3.03%). Anti-WNV IgM antibodies were detected in 16 equids (2.21%), and 3 animals were doubtful (0.41%). All ELISA-reactive positive/doubtful sera (N=226) were further tested by micro-virus neutralization test (VNT), and a total of 143 horses were confirmed as positive for WNV, obtaining a seroprevalence of 19.72% in equids of western Spain. In addition, specific antibodies against USUV were confirmed in 11 equids. In 24 equids, a specific flavivirus species (detected by ELISA test) could not be determined. The generalized linear mixed-effects models showed that the significant risk factors associated with individual WNV infection in equids were the age (adults) and hair coat colour (light), whereas in USUV infections, it was the breed (pure). Data demonstrated that WNV and USUV are circulating in regions of western Spain. Given the high WNV seroprevalence found in equids from the studied areas, it is important to improve the surveillance programmes of public health to detect undiagnosed human cases and to establish a vaccination programme in equid herds in these regions.

Bovine and equine trypanosomosis in Northwest Ethiopia: Prevalence, density of vectors and control measures

A cross-sectional study was carried out from November 2016 to May 2017 in selected districts of Northwest Ethiopia (Jawi, South Achefer, Dembecha and Jabitehenan) with the aim of determining the prevalence of bovine and equine trypanosomosis, estimating the apparent density of vectors and assessing the effectiveness of control measures of the disease. A total of 1257 animals of which 803 bovine and 454 equine were examined for the determination of prevalence using blood sample collected from ear vein of animals. The buffy coat technique was employed to determine the prevalence and the packed cell volume (PCV) value. During sampling animals were categorized into age, body condition score, sex and hair coat color. A total of 40 monoconical traps 10 per district were deployed to estimate the apparent density of vectors. To assess control measures representative number of farmers were interviewed with a prepared questionnaire and using secondary data from veterinary offices. The overall prevalence of trypanosomosis was 7.47% and 4.40% for bovine and equine species, respectively. The prevalence of bovine trypanosomosis was 9.46%, 6.13%, 8.11% and 5.98% while prevalence in equine was 7.8%, 5.3%, 2.7% and 1.8% in Jawi, South Achefer, Dembecha and Jabitehenan districts, respectively. Significance differences in the prevalence of trypanosomosis were observed in hair coat color, age and body condition score in bovine while only body condition was significant in equine. The mean PCV value of parasitemic animals was significantly (P < .001) lower than that of aparasitaemic animals. The apparent densities of vectors were 1.04, 0.97, 0.32 fly/trap/day for Glossina, Stomoxys and Tabanus respectively. Glossina m. submorsitans and G. tachinoides were the species of tsetse identified. The questionnaire response indicated that trypanosomosis was found to be a serious constraint on livestock health in the study areas. The application of continuous trypanosomosis control measures particularly in Jawi and South Achefer districts which were showed an increasing trend in livestock number might be attributed to control effectiveness. In conclusion the presence of trypanosomes and potential vectors necessitate the application of sustainable and integrated control methods in the study areas.

English

Phenotypic characterization is used to identify and document diversity within and between distinct breeds, based on their observable attributes. Study to assess the body characteristics and variability of 204 Djallonke (West African dwarf) ewes was conducted in three agro-ecological zones (central, western and northern) of Cote d’Ivoire, from November 2016 to April 2017. Animals were described using visual appreciation of the body hair coat (colour type and pattern), hair length, ear orientation, tail type and the facial (head) profile. The linear body measurements, such as ear and tail length, muzzle length and width, height at wither, chest depth, and chest girth were also described. The data collected were subjected to principal component (PCA) and discriminant analysis. Results showed that the most common Djallonke ewes had erected ear (87.25%), thin tail and straight face. The dominant colour pattern of the body hair coat was patchy (64.22%) followed by plain (32.84%) and spotted (2.94%). The agro-ecological zone had a significant (pE‚0.01) effect on some linear body measurements (muzzle length, ear length and height wither). Based on PCA performed with all the above morphological variabilities, we were able to segregate the Djallonke ewes’ into three clusters (I, II and III). Discriminant analysis revealed that 76.27% sheep of cluster I, 92.80% sheep of cluster II and 90% sheep of cluster III were correctly classified in their original cluster. This result indicated that Ivorian Djallonke sheep population comprises of three well characterized morphological types of animals. This information could constitute a basis for further characterization and development of conservation strategies for Djallonke sheep breeding in Cote d’Ivoire. Key words: Local, sheep, breed, morphological, variability, West Africa.

The impact of hair coat color on physiological variables, reproductive performance and milk yield of Holstein cows in a hot environment

Vulnerable animals to heat stress have been described as ones with dark or black hides due to increasing absorption of solar radiation. The effect of coat color in pluriparous contemporary Holstein cows in a hot environment (mean annual temperature 24.6 °C), on body surface temperature (infrared thermography), physiological and hematological variables as well as milk yield and reproductive performance was assessed using 178 Holstein pluriparous cows (74 predominantly white and 104 predominantly black). Data were collected in the morning and afternoon in July (mean temperature-humidity index 82 units). Body condition score at mid-lactation (128 ± 32 days in milk at the start of the experiment) was higher (P < 0.01) in predominantly white than in black cows (3.3 vs. 3.2). Respiration rate did not differ between groups (72 ± 23 vs. 73 ± 20 breaths/min for white and black cows, respectively, sampling time combined). In contrast, rectal temperature of black cows was 0.1 °C higher (P ≤ 0.01) than white cows, regardless of sampling time. The only significant hematologic change was a slight increase in mean corpuscular volume in black cows (54.7 fL, P < 0.01) compared to white cows (53.8 fL), but it remained within the reference range. Differences due to coat color did not alter body surface temperatures at any time of the day. Conception rates, services per conception, calving intervals and fetal losses were not associated with hair coat color, but cows with predominantly white coat produced 394 kg more (P < 0.01) fat-corrected milk in 305 days compared to cows with predominantly black coat. It was concluded that in this hot-arid environment with cows housed in facilities with extensive cooling, black hair coat moderately reduces 305-d milk yield without affecting milk composition, body surface temperature, and reproductive performance.