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1.
J Anim Sci ; 98(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31863114

RESUMO

The keratin-associated proteins (KAPs) are structural components of wool fibers and variation in the genes encoding the KAPs can affect wool traits. In this study, sequence variation in the ovine KAP7-1 gene (KRTAP7-1) was investigated in 222 sheep across 5 different Pakistani breeds and breed crosses. Two previously identified variants (A and B) of the KRTAP7-1 coding sequence were identified. The frequency of the genotypes AA and AB was 76% and 23%, respectively, and that of BB was 1%. The association of sequence variation with various wool traits and measurements included yield (the proportion of greasy fleece weight that is clean fleece), mean staple length (MSL), wool bulk, mean fiber diameter, fiber diameter SD, the coefficient of variation of fiber diameter, medullation, the SD of medullation, the coefficient of variation of medullation, fiber opacity, the SD of opacity, and the coefficient of variation of opacity. Variation in KRTAP7-1 was found to be associated with yield (P = 0.017). The adjusted mean yield of sheep of genotype AA (n = 169) was 79.9 ±â€…2.72%, while that of genotype AB (n = 51) was 81.9 ±â€…3.37%. There was also an association between variation in KRTAP7-1 and MSL (P = 0.024), with sheep of genotype AA (n = 169) having an adjusted mean MSL of 47.3 ±â€…0.57 mm compared with sheep of genotype AB (n = 51, 50.9 ±â€…0.65 mm). Yield and MSL are both important wool production traits, hence variation in KRTAP7-1 needs to be further investigated in more sheep of differing breed.


Assuntos
Queratinas Específicas do Cabelo/genética , Polimorfismo Genético , Ovinos/genética , Lã/crescimento & desenvolvimento , Animais , Peso Corporal/genética , Cruzamento , Genótipo , Queratinas/genética , Fenótipo
2.
PLoS One ; 14(1): e0208229, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30605467

RESUMO

The correlations between growth and wool traits in response to canola and flaxseed oil supplementation were evaluated in Australian prime lambs. Sixty dual-purpose prime lambs including purebred Merino and crossbred lambs were allocated to one of five treatments of lucerne hay basal diet supplemented with isocaloric and isonitrogenous wheat-based pellets. Treatments were: no oil inclusion (Control); 2.5% canola oil; 5% canola oil; 2.5% flaxseed oil and 5% flaxseed oil, with lamb groups balanced by breed and gender. Each lamb was daily supplemented with 1kg of pellets and had free access to lucerne hay and water throughout the 7-week feeding trial, after a 3-week adaptation. Individual animal basal and supplementary pellet feed intakes were recorded daily, while body conformation traits, body condition scores and liveweights were measured on days 0, 21, 35 and 49. The lambs were dye-banded on the mid-side and shorn before commencing the feeding trial and mid-side wool samples were collected from the same dye-banded area of each lamb at the end of the experiment. Correlations between wool quality traits and lamb performance were non-significant (P>0.05). Oil supplementation had no detrimental effect on lamb growth and wool quality traits (P > 0.05). Gender significantly affected wither height gain and fibre diameter. There were significant interactions between oil supplementation and lamb breed on chest girth. The correlations between clean fleece yield (CFY) and other wool quality traits were moderate ranging from 0.29 to 0.55. Moderate to high correlations between fibre diameter (FD) and other wool quality traits were detected (0.46-0.99) with the strongest relationship between FD and wool spinning fineness (SF). The relationship between CFY and wool comfort factor (CF) were positive, while negative relationships between CFY and the others were observed. A combination of 5% oil supplementation and genetics is an effective and strategic management tool for enhancing feed efficiency and growth performance without negative effects on wool quality in dual-purpose lamb production. This is a good outcome for dual-purpose sheep farmers. It essentially means the absorbed nutrients in supplemented lambs yielded good growth performance without any detrimental impact on wool quality; a win-win case of nutrient partitioning into the synthesis of muscle and wool without compromising either traits.


Assuntos
Suplementos Nutricionais , Variação Genética , Óleo de Semente do Linho/farmacologia , Óleo de Brassica napus/farmacologia , Ovinos/crescimento & desenvolvimento , Ovinos/genética , Lã/crescimento & desenvolvimento , Animais , Austrália , Cruzamento , Feminino , Masculino , Lã/efeitos dos fármacos
3.
Anim Genet ; 49(5): 428-437, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30066430

RESUMO

Rabbit fur characteristics are primarily genetically determined traits. We used Illumina high-throughput sequencing technology to assess gene expression in the skin tissues of rabbits derived from a cross between Wanxi Angora rabbits and Rex rabbits, which exhibit differential characteristics of short and long wool respectively, to investigate molecular mechanisms related to wool length determination. To identify key regulatory genes involved in rabbit wool length, genes that were differentially expressed between the long- and short-wool rabbits based on a P-value < 0.05 and log2 |fold change| > 1 were characterized. A total of 798 genes were up-regulated and 523 were down-regulated in the long-wool group compared to expression levels in the short-wool group, and these genes were annotated with GO terms and KEGG pathways, revealing wool-development-related biological functions. The Wnt, Hedgehog and TGF-ß signaling pathways, which are related to cell proliferation, fibroblast proliferation and hair follicle regulation respectively, were identified. The expression levels of eight genes were validated by RT-qPCR. In addition, an interaction network was constructed to show the regulatory relationships among the differentially expressed genes. In this study, we found that FGF5, WNT5A, BMP4 and BMP7 showed significant differential expression between the two groups. These transcriptomic profiling results provide comprehensive gene expression information for improving understanding of the molecular mechanisms involved in the growth and development of rabbit wool.


Assuntos
Perfilação da Expressão Gênica , Coelhos/genética , Lã/crescimento & desenvolvimento , Animais , Sequenciamento de Nucleotídeos em Larga Escala , Coelhos/crescimento & desenvolvimento
4.
Adv Exp Med Biol ; 1054: 89-96, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29797270

RESUMO

The anagen phase of the hair follicle cycle is when the follicle is configured to grow hair. In short hairs (e.g., mouse underhairs and human eye lashes) anagen phase is short, but in the wool of sheep and in human scalp hair anagen is a prolonged state lasting for years. In this chapter we describe the morphological and biological divisions within the anagen follicle.


Assuntos
Folículo Piloso/crescimento & desenvolvimento , Cabelo/crescimento & desenvolvimento , Animais , Humanos , Camundongos , Couro Cabeludo , Ovinos , Lã/crescimento & desenvolvimento
5.
J Proteomics ; 172: 82-88, 2018 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-29051081

RESUMO

The structural component of wool and hair fibers, such as keratin-associated proteins (KAPs), has been well described, but the genetic determinants of fiber diameter are largely unknown. Here, we have used an iTRAQ-based proteomic approach to investigate differences in protein abundance among 18 samples from sheep and goats across a diverse range of fibers. We identified proteins with different abundance and are associated with variation in fiber features. Proteins with different abundance are mainly keratin or keratin-associated proteins (KRTAP11-1, KRT6A, KRT38), or are related to hair growth (DSC2, DSG3, EEF2, CALML5, TCHH, SELENBP1) and fatty acid synthesis (FABP4, FABP5). RNA-seq further confirmed the functional importance of the DSC2 gene in the determination of woolly phenotype in goat fibers. This comprehensive analysis of fibers from major fiber-producing animals is the first to provide a list of candidate proteins that are involved in fiber formation. This list will be valuable asset for future studies into the molecular mechanisms that underlie fiber diversity. BIOLOGICAL SIGNIFICANCE: Proteins are the basis for animal-derived hair fibers, yet proteins conferring fiber structure and characteristics in sheep and goats are largely elusive. By examining 27 fibers samples representing 9 fiber types from sheep and goats through the iTRAQ approach, we show a list of differentially abundant proteins that are important to hair structural component, or genes related to hair growth and fatty acid synthesis. RNA-seq further validated the DSC2 gene is key to the woolly/straight hair phenotype in goats.


Assuntos
Cabelo/química , Proteômica/métodos , Lã/química , Animais , Desmocolinas/genética , Ácidos Graxos/biossíntese , Cabras , Cabelo/crescimento & desenvolvimento , Ovinos , Lã/crescimento & desenvolvimento
6.
Genome ; 60(12): 1060-1067, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28850794

RESUMO

Fur is an important economic trait in rabbits. The identification of genes that influence fur development and knowledge regarding the actions of these genes provides useful tools for improving fur quality. However, the mechanism of fur development is unclear. To obtain candidate genes related to fur development, the transcriptomes of tissues from backs and bellies of Chinchilla rex rabbits were compared. Of the genes analyzed, 336 showed altered expression in the two groups (285 upregulated and 51 downregulated, P ≤ 0.05, fold-change ≥2 or ≤0.5). Using GO and KEGG to obtain gene classes that were differentially enriched, we found several genes to be involved in many important biological processes. In addition, we identified several signaling pathways involved in fur development, including the Wnt and MAPK signaling pathways, revealing mechanisms of skin and hair follicle development, and epidermal cell and keratinocytes differentiation. The obtained rabbit transcriptome and differentially expressed gene profiling data provided comprehensive gene expression information for SFRP2, FRZB, CACNG1, SLC25A4, and SLC16A3. To validate the RNA-seq data, the expression levels of eight differentially expressed genes involved in fur development were confirmed by qRT-PCR. The results of rabbit transcriptomic profiling provide a basis for understanding the molecular mechanisms of fur development.


Assuntos
Coelhos/genética , Transcriptoma , Lã/crescimento & desenvolvimento , Animais , Perfilação da Expressão Gênica , Folículo Piloso/citologia , Queratinócitos/citologia , Lã/normas
7.
Gene ; 627: 477-483, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28666779

RESUMO

Fibroblast growth factor 5 (FGF5) has been recognized as an inhibitor to cease animal hair growth, while in contrary, FGF5 short alternative transcript (FGF5s) can induce hair growth by antagonizing FGF5 function. To investigate the role of FGF5s in wool growth in Chinese Merino sheep, we generated transgenic sheep of ectopic expression of FGF5s by injection of recombinant lentivirus into zygote. Totally 20 transgenic sheep were obtained and 12 were alive after birth. Characterization of the transgene revealed that the transgenic sheep showed variety of integrant, ranged from 2 to 11 copies of transgene. The ectopic expression of FGF5s was observed in all transgenic sheep. Further study on the effect of ectopic expression of FGF5s revealed that the wool length of transgenic sheep were significantly longer than that of non-transgenic control, with 9.17cm of transgenic lambs versus 7.58cm of control animals. Notably, besides the increase of wool length, the yearling greasy fleece weight was also concordantly greater than that of wild-type (p<0.01), with 3.22kg of transgenic sheep versus 2.17kg of control lambs (p<0.01) in average. Our results suggested that overexpression of FGF5s could stimulate wool growth and resulted in increase of wool length and greasy wool weight.


Assuntos
Animais Geneticamente Modificados/genética , Fator 5 de Crescimento de Fibroblastos/genética , Ovinos/genética , Lã/crescimento & desenvolvimento , Animais , Fator 5 de Crescimento de Fibroblastos/metabolismo , Lã/metabolismo
8.
J Anim Sci ; 95(5): 1879-1891, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28726993

RESUMO

Genetic correlations between 29 wool production and quality traits and live weight and ultrasound fat depth (FAT) and eye muscle depth (EMD) traits were estimated from the Information Nucleus (IN). The IN comprised 8 genetically linked flocks managed across a range of Australian sheep production environments. The data were from a maximum of 9,135 progeny born over 5 yr from 184 Merino sires and 4,614 Merino dams. The wool traits included records for yearling and adult fleece weight, fiber diameter (FD), staple length (SL), fiber diameter CV (FDCV), scoured color, and visual scores for breech and body wrinkle. We found high heritability for the major yearling wool production traits and some wool quality traits, whereas other wool quality traits, wool color, and visual traits were moderately heritable. The estimates of heritability for live weight generally increased with age as maternal effects declined. Estimates of heritability for the ultrasound traits were also higher when measured at yearling age rather than at postweaning age. The genetic correlations for fleece weight with live weights were positive (favorable) and moderate (approximately 0.5 ± 0.1), whereas those with FD were approximately 0.3 (unfavorable). The other wool traits had lower genetic correlations with the live weights. The genetic correlations for FAT and EMD with FD and SL were positive and low, with FDCV low to moderate negative, but variable with wool weight and negligible for the other wool traits. The genetic correlations for FAT and EMD with postweaning weight were positive and high (0.61 ± 0.18 to 0.75 ± 0.14) but were generally moderate with weights at other ages. Selection for increased live weight will result in a moderate correlated increase in wool weight as well as favorable reductions in breech cover and wrinkle, along with some unfavorable increases in FD and wool yellowness but little impact on other wool traits. The ultrasound meat traits, FAT and EMD, were highly positively genetically correlated (0.8), and selection to increase them would result in a small unfavorable correlated increase in FD, moderately favorable reductions in breech cover and wrinkle, but equivocal or negligible changes in other wool traits. The estimated parameters provide the basis for calculation of more accurate Australian Sheep Breeding Values and selection indexes that combine wool and meat objectives in Merino breeding programs.


Assuntos
Carne Vermelha/normas , Ovinos/genética , Lã/crescimento & desenvolvimento , Animais , Austrália , Peso Corporal , Cruzamento , Feminino , Genótipo , Masculino , Fenótipo , Gravidez , Ovinos/anatomia & histologia , Ovinos/crescimento & desenvolvimento
9.
J Anim Sci ; 95(5): 2019-2024, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28727005

RESUMO

Sheep are an important source of fiber production. Fibroblast growth factor 5 (FGF5) is a dominant inhibitor of length of the anagen phase of the hair cycle. Knockout or silencing of the gene results in a wooly coat in mice, donkeys, dogs, and rabbits. In sheep breeding, wool length is one of the most important wool quality traits. However, traditional breeding cannot accurately and efficiently mediate an advanced genotype into the sheep genome. In this study, we generated 3 knockout sheep via the 1-step clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system. Sequencing analysis confirmed that mutations in the gene existed in all germ lines of 3 founders: besides the intact sequence, 3 kinds of deletions in the gene (including 5, 13, and 33 bp) were detected. The changes in the primary and senior structure of the FGF5 protein due to the 3 deletions in founders suggested that the FGF5 protein was dysfunctional. In addition, the expression level of intact mRNA in heterozygous individuals decreased compared with the wild types ( < 0.01). Functionally, we discovered that wool length in founders was significantly longer than in wild types ( < 0.05). Collectively, the knockout sheep with the longer wool length phenotype will provide an efficient way for fast genetic improvement of sheep breeding and promote the development of wool industry.


Assuntos
Sistemas CRISPR-Cas , Fator 5 de Crescimento de Fibroblastos/genética , Genoma/genética , Ovinos/genética , Lã/crescimento & desenvolvimento , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Feminino , Fator 5 de Crescimento de Fibroblastos/metabolismo , Edição de Genes/veterinária , Técnicas de Inativação de Genes/veterinária , Genótipo , Heterozigoto , Masculino , Modelos Moleculares , Mutação , Fenótipo , RNA Mensageiro/genética , Alinhamento de Sequência , Análise de Sequência de DNA/veterinária , Ovinos/crescimento & desenvolvimento
10.
J Anim Sci ; 95(6): 2385-2398, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28727038

RESUMO

Genetic correlations between 29 wool production and quality traits and 14 whole carcass measures and carcass component traits were estimated from the Information Nucleus of 8 flocks managed across a range of Australian sheep production environments and genetically linked. Wool data were from over 5,000 Merino progeny born over 5 yr, whereas carcass data were from over 1,200 wether progeny of over 176 sires, slaughtered at about 21 kg carcass weight, on average. Wool traits included yearling and adult records for wool weight, fiber diameter, fiber diameter variation, staple strength, scoured color, and visual scores for breech and body wrinkle. Whole carcass measures included HCW, dressing percentage (DP), and various measures of fat depth and eye muscle dimensions. Carcass components were obtained by dissection, and lean meat yield (LMY) was predicted. Heritability estimates for whole carcass measures ranged from 0.12 ± 0.08 to 0.35 ± 0.10 and ranged from 0.17 ± 0.10 to 0.46 ± 0.10 for carcass dissection traits, with no evidence of important genotype × environment interactions. Genetic correlations indicated that selection for increased clean wool weight will result in reduced carcass fat (-0.17 to -0.34) and DP (-0.48 ± 0.15), with little effect on carcass muscle. Selection for lower fiber diameter will reduce HCW (-0.48 ± 0.15) as well as carcass fat (0.14 to 0.27) and muscle (0.21 to 0.50). There were high genetic correlations between live animal measures of fat and muscle depth and the carcass traits (generally greater than 0.5 in size). Selection to increase HCW (and DP) will result in sheep with fewer wrinkles on the body (-0.57 ± 0.10) and barer breeches (-0.74 ± 0.12, favorable), with minor deterioration in scoured wool color (reduced brightness and increased yellowness). Selection for reduced fat will also result in sheep with fewer body wrinkles (-0.42 to -0.79). Increasing LMY in Merinos through selection would result in a large reduction in carcass fat and DP (-0.66 to -0.84), with a smaller increase in carcass muscle and some increase in wool weight and wrinkles. Although no major antagonisms are apparent between the wool and carcass traits, developing selection indexes for dual-purpose wool and meat breeding objectives will require accurate estimates of genetic parameters to ensure that unfavorable relationships are suitably considered. The findings will aid development of dual-purpose wool and meat breeding objectives.


Assuntos
Ovinos/genética , Lã/crescimento & desenvolvimento , Animais , Austrália , Peso Corporal , Cruzamento , Cor , Feminino , Genótipo , Masculino , Fenótipo , Carne Vermelha , Ovinos/crescimento & desenvolvimento
11.
FEBS J ; 284(17): 2764-2773, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28631368

RESUMO

Fibroblast growth factor 5 (FGF5) regulates hair length in humans and a variety of other animals. To investigate whether FGF5 has similar effects in sheep, we used clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated 9 (Cas9) to generate loss-of-function mutations with the FGF5 gene in Chinese Merino sheep. A total of 16 lambs were identified with genetic mutations within the targeting locus: 13 lambs had biallelic modifications and three lambs had monoallelic modifications. Characterization of the modifications revealed that 13 were frameshift mutations that led to premature termination, whereas the other three were in-frame deletions. Thus, CRISPR/Cas9 efficiently generated loss-of-function mutations in the sheep FGF5 gene. We then investigated the effect of loss of FGF5 function on wool traits in 12 lambs and found that wool staple length and stretched length of genetically modified (GM) yearling sheep were significantly longer compared with that of wild-type (WT) control animals. The greasy fleece weight of GM yearling sheep was also significantly greater compared with that of WT sheep. Moreover, the mean fiber diameter in GM sheep showed no significant difference compared with WT sheep, suggesting that the increase in greasy fleece weight was likely attributed to the increase in wool length. The results of this study suggest that CRISPR/Cas9-mediated loss of FGF5 activity could promote wool growth and, consequently, increase wool length and yield.


Assuntos
Fator 5 de Crescimento de Fibroblastos/genética , Carneiro Doméstico/genética , Lã/crescimento & desenvolvimento , Animais , Sequência de Bases , Sistemas CRISPR-Cas , Fator 5 de Crescimento de Fibroblastos/metabolismo , Carneiro Doméstico/crescimento & desenvolvimento
12.
Anim Genet ; 48(1): 67-79, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27611105

RESUMO

Identifying genes of major effect for wool growth would offer strategies for improving the quality and increasing the yield of fine wool. In this study, we employed the Agilent Sheep Gene Expression Microarray and proteomic technology to investigate the gene expression patterns of body side skin (more wool growing) in Aohan fine wool sheep (a Chinese indigenous breed) in comparison with groin skin (no wool growing) at the anagen stage of the wool follicle. A microarray study revealed that 4772 probes were differentially expressed, including 2071 upregulated and 2701 downregulated probes, in the comparisons of body side skin vs. groin skin (S/G). The microarray results were verified by means of quantitative PCR. A total of 1099 probes were assigned to unique genes/transcripts. The number of distinct genes/transcripts (annotated) was 926, of which 352 were upregulated and 574 were downregulated. In S/G, 13 genes were upregulated by more than 10 fold, whereas 60 genes were downregulated by more than 10 fold. Further analysis revealed that the majority of the genes possibly related to the wool growth could be assigned to categories including regulation of cell division, intermediate filament, cytoskeletal part and growth factor activity. Several potential gene families may participate in hair growth regulation, including fibroblast growth factors, transforming growth factor-ß, WNTs, insulin-like growth factor, vascular endothelial growth factors and so on. Proteomic analysis also revealed 196 differentially expressed protein points, of which 121 were identified as single protein points.


Assuntos
Perfilação da Expressão Gênica , Proteômica , Carneiro Doméstico/genética , Lã/crescimento & desenvolvimento , Animais , Análise por Conglomerados , Feminino , Expressão Gênica , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Pele
13.
PLoS One ; 11(11): e0166374, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27832155

RESUMO

Crossbreeding of Australian Superfine Merinos (ASMs) with Gansu Alpine Finewool (GAF) sheep and an evaluation of the potential benefits of this genetic cross has not been previously conducted. 13 ASMs were crossbred with GAF sheep over a five year period with backcrossing designed to assess heterosis. Data from 11,178 lambs sired by 189 rams were used in the study. Genotype, birth year, birth type, dam age, sex and/or management group, and record age were fitted as fixed effects and within-genotype sire fitted as a random effect. Crossbreeds of 1/2 ASM expressed the most desirable effects for improving average fiber diameter (AFD), clean fleece weight (CFW), yield, coefficient of variation of AFD (CVAFD), yearling staple length (YSL) to AFD ratio (YSL/AFD), and CFW to metabolic yearling bodyweight (YWT0.75) ratio (CFW/YWT0.75) but showed the least post-weaning average daily gain (powADG) and YWT. Genotype of backcrossing with 1/4 ASM obtained moderate improvements in AFD, CFW, CVAFD, and YSL/AFD but the highest YSL, WWT, and prwADG. Except for yield (-1.42%) and CFW/YWT0.75 (-1%), heterosis estimates were generally low and positive, and ranged from 0.1% for CVAFD to 4% for powADG, which indicates the potential to improve relevant traits through exploiting heterosis to a varying extent. The ASMs sampled in this study were found to be superior to GAFs for AFD, CFW, yield, and CVAFD by 19.82%, 11.68%, 14.47%, and 6.99%, respectively, but inferior for YSL, PowADG, and YWT by 4.36%, 50.97%, and 16.93%, respectively. ASMs also appeared to be more efficient than GAFs in clean wool production (25.34%) and staple length growth (16.17%). The results of our study strongly suggest that an infusion of ASM genes via crossbreeding is an effective and appropriate approach to improve wool microns and wool production from GAF sheep, and we make recommendations to tackle the undesirable traits of YWT and YSL from ASM introduction.


Assuntos
Cruzamento/métodos , Cruzamentos Genéticos , Carneiro Doméstico/crescimento & desenvolvimento , Carneiro Doméstico/genética , Lã/crescimento & desenvolvimento , Animais , Austrália , Feminino , Genótipo , Vigor Híbrido , Masculino , Lã/metabolismo
14.
Reprod Fertil Dev ; 28(1-2): 94-111, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27062878

RESUMO

The effect of the Developmental Origins of Health and Disease on the spread of non-communicable diseases is recognised by world agencies such as the United Nations and the World Health Organization. Early environmental effects on offspring phenotype also apply to domestic animals and their production traits. Herein, we show that maternal nutrition not only throughout pregnancy, but also in the periconception period can affect offspring phenotype through modifications of gametes, embryos and placental function. Because epigenetic mechanisms are key processes in mediating these effects, we propose that the study of epigenetic marks in gametes may provide additional information for domestic animal selection.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Gado/fisiologia , Carne , Leite , Modelos Biológicos , Seleção Artificial , Lã/crescimento & desenvolvimento , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Desenvolvimento Embrionário , Epigênese Genética , Feminino , Desenvolvimento Fetal , Qualidade dos Alimentos , Cabelo/química , Cabelo/crescimento & desenvolvimento , Cabelo/metabolismo , Gado/crescimento & desenvolvimento , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Carne/análise , Leite/química , Leite/metabolismo , Placentação , Gravidez , Controle de Qualidade , Nações Unidas , Lã/química , Lã/metabolismo , Organização Mundial da Saúde
15.
Genet Mol Res ; 14(4): 13754-63, 2015 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-26535691

RESUMO

MicroRNAs are very small endogenous RNA molecules that play a crucial role in an array of biological processes, including regulation of skin morphogenesis. The microRNA let-7b is thought to modulate animal hair growth, by binding target genes that encode growth factors. Fibroblast growth factor 5 (FGF5) has been previously reported to be involved in the initiation of the catagen phase of hair growth. In this study, we combined previous reports with bioinformatic analysis techniques to identify and validate FGF5 and, using lucerifase assay, confirmed targeted binding of let-7b to FGF5. To investigate the interaction between let-7b and FGF5, alpaca skin fibroblasts were transfected with let-7b over-expression vectors, and then mRNA and protein expression levels of FGF5 and the gene encoding its receptor, FGFR1, were evaluated. Levels of FGF5 mRNA and protein were remarkably lower in transfected groups, as compared to controls. In summary, this study confirmed that let-7b acts as a regulator of skin morphogenesis, by directly targeting FGF5 and down-regulating its expression. It provides the evidence of hair growth regulated by miRNAs in animals and may have important applications in wool production.


Assuntos
Camelídeos Americanos/genética , Fator 5 de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica , MicroRNAs/genética , Lã/crescimento & desenvolvimento , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Regulação para Baixo , Fator 5 de Crescimento de Fibroblastos/metabolismo , MicroRNAs/química , Transporte Proteico , Interferência de RNA , RNA Mensageiro/química , RNA Mensageiro/genética
16.
J Anim Sci ; 93(10): 4601-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26523551

RESUMO

Methionine synthase (MTR) plays a crucial role in maintaining homeostasis of intracellular methionine, folate, and homocysteine, and its activity correlates with DNA methylation in many mammalian tissues. Our previous genomewide association study identified that 1 SNP located in the gene was associated with several wool production and quality traits in Chinese Merino. To confirm the potential involvement of the gene in sheep wool production and quality traits, we performed sheep tissue expression profiling, SNP detection, and association analysis with sheep wool production and quality traits. The semiquantitative reverse transcription PCR analysis showed that the gene was differentially expressed in skin from Merino and Kazak sheep. The sequencing analysis identified a total of 13 SNP in the gene from Chinese Merino sheep. Comparison of the allele frequencies revealed that these 13 identified SNP were significantly different among the 6 tested Chinese Merino strains ( < 0.001). Linkage disequilibrium analysis showed that SNP 3 to 11 were strongly linked in a single haplotype block in the tested population. Association analysis showed that SNP 2 to 11 were significantly associated with the average wool fiber diameter and the fineness SD and that SNP 4 to 11 were significantly associated with the CV of fiber diameter trait ( < 0.05). Single nucleotide polymorphism 2 and SNP 5 to 12 were weakly associated with wool crimp. Similarly, the haplotypes derived from these 13 identified SNP were also significantly associated with the average wool fiber diameter, fineness SD, and the CV of fiber diameter ( < 0.05). Our results suggest that is a candidate gene for sheep wool production and quality traits, and the identified SNP might be used in sheep breeding.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Ovinos/genética , Lã/crescimento & desenvolvimento , Animais , China , Regulação Enzimológica da Expressão Gênica/fisiologia , Ligação Genética , Estudo de Associação Genômica Ampla , Haplótipos , Desequilíbrio de Ligação , Fenótipo , Polimorfismo de Nucleotídeo Único , Ovinos/fisiologia
17.
Parasit Vectors ; 8: 557, 2015 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-26496893

RESUMO

BACKGROUND: Gastrointestinal nematode (GIN) infections are common in domestic sheep and impact directly and indirectly on the health of infected animals as well as on the associated economic production. In this study, we aim at summarizing the current knowledge on the influence of GIN infections on sheep production by conducting a systematic review. A subsequent meta-analysis of relevant studies was performed to provide an estimate of the effect of GIN infections on weight gain, wool production and milk yield. METHODS: A literature search was performed on the CAB, Pubmed and Web of Science database for the period 1960-2012. Inclusion criteria were: 1) Measurement of at least one production parameter. 2) Comparison between groups of sheep with different nematode burdens. 3) Same conditions regarding all aspects except parasite burden between groups. 4) Quantitative measurements of one or more production traits. RESULTS: Altogether, 88 studies describing 218 trials were included in this review. The majority of studies (86%) reported that GIN infections had a negative effect on production but this was reported to be statistically significant in only 43% of the studies. Meta-analysis indicated that performances of sheep infected with nematodes was 85, 90 and 78% of the performance in uninfected individuals for weight gain, wool production and milk yield respectively. Our results suggest a possible reporting bias or small study effect for the estimation of the impact of GIN infections on weight gain. Finally, a general linear model provided an estimate for the decrease in weight gain in relation to the increase in faecal egg count of nematodes. CONCLUSION: This study underlines the importance of GIN infections for sheep production and highlights the need to improve parasite management in sheep, in particular in face of challenges such as anthelmintic resistance.


Assuntos
Peso Corporal , Enteropatias Parasitárias/veterinária , Leite/metabolismo , Infecções por Nematoides/veterinária , Doenças dos Ovinos/patologia , Ovinos/crescimento & desenvolvimento , Lã/crescimento & desenvolvimento , Animais , Helmintíase/parasitologia , Helmintíase/patologia , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/patologia , Lactação , Infecções por Nematoides/parasitologia , Infecções por Nematoides/patologia , Doenças dos Ovinos/parasitologia
18.
J Anim Sci ; 93(3): 1327-31, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26020909

RESUMO

Production characteristics of white-faced rams have been systematically evaluated over a 140-d test in Wyoming since 1961. Individual test records ( = 4,240) from rams on test were analyzed to determine change over the past 52 yr. Although rams on test are not older, weight on and off test has increased ( < 0.001) since 1961. Weight off test increased 22.7 kg and contributed to an increase ( < 0.001) in clean fleece weight. Rate of gain ( < 0.001) almost doubled over this 50-yr period. Growth efficiency improved from 0.23 ± 0.01 kg/d from 1961 to 1966 to 0.39 ± 0.01 kg/d from 2008 to 2013. Cubic, rather than linear, effects better explain the change in growth characteristics, suggesting a plateau or tapering of these traits. Wool characteristics remain an important component of the test index, and despite increases in body size and gain, wool diameter was unchanged ( > 0.15). Average daily gain correlated ( > 0.67; < 0.001) with lamb and feeder lamb price, with the strongest correlation at a 2-yr ( > 0.76) time lag. U.S. sheep inventory was negatively correlated ( > -0.72; < 0.001) with sheep price and ADG, with the greatest correlation at no time lag. Wool price 0, 2, or 5 yr prior did not correlate ( < 0.1; ≥ 0.5) with spinning count. Influences on white-faced ram selection appear to have largely impacted growth traits while avoiding negative impacts on wool quality.


Assuntos
Peso Corporal/genética , Peso Corporal/fisiologia , Ovinos/genética , Ovinos/fisiologia , Lã/crescimento & desenvolvimento , Animais , Cruzamento , Masculino , Fatores de Tempo , Wyoming
19.
Trop Anim Health Prod ; 47(3): 567-73, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25616983

RESUMO

This experiment was conducted to investigate the seasonal pattern of hair follicle activity, wool growth and fibre diameter (FD) in Sanjabi sheep in west Iran, Kermanshah (34° 18' N and 47° 3' E, elevation 1420 m). Ten male and 10 female Sanjabi sheep with an initial live weight of 32.1 ± 1.3 and 32.7 ± 1.5 (means ± SD), respectively, were used in a 365-day study. A diet was offered with an estimated concentration of 2.18 Mcal metabolizable energy and 130.0 g/kg DM crude protein. Body weight, average daily gain (ADG) and dry matter intake (DMI) were recorded weekly. The percentages of active primary and secondary wool follicles (PAP and PAS), follicle density and the ratio of secondary to primary follicles (S/P) were determined from skin biopsies, taken from the right mid-side of the sheep at monthly intervals. Raw and clean fibre growth rates and FD were measured from left mid-side patches (10 × 10 cm) harvested at the end of every month. There was a gradual increase in live weight throughout the experiment, while ADG and DMI changed in concert with day length. The greatest values for PAP and PAS were observed in summer, whereas lowest were obtained in winter (p < 0.001). Clean wool growth rate and FD were greatest (p < 0.001) in summer and lowest (p < 0.001) in winter. It is concluded that a seasonal cycle of feed intake, body growth, fibre follicle activity, wool growth and FD occur in fat-tailed Sanjabi sheep.


Assuntos
Folículo Piloso/crescimento & desenvolvimento , Lã/crescimento & desenvolvimento , Animais , Feminino , Irã (Geográfico) , Masculino , Estações do Ano , Ovinos
20.
J Anim Physiol Anim Nutr (Berl) ; 99(3): 483-91, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25271888

RESUMO

Ruminant methane yield (MY) is positively correlated with mean retention time (MRT) of digesta. The hormone triiodothyronine (T3 ), which is negatively correlated with ambient temperature, is known to influence MRT. It was hypothesised that exposing sheep to low ambient temperatures would increase plasma T3 concentration and decrease MRT of digesta within the rumen of sheep, resulting in a reduction of MY. To test this hypothesis, six Merino sheep were exposed to two different ambient temperatures (cold treatment, 9 ± 1 °C; warm control 26 ± 1 °C). The effects on MY, digesta MRT, plasma T3 concentration, CO2 production, DM intake, DM digestibility, change in body weight (BW), rumen volatile fatty acid (VFA) concentrations, estimated microbial protein output, protozoa abundance, wool growth, water intake, urine output and rectal temperature were studied. Cold treatment resulted in a reduction in MY (p < 0.01); digesta MRT in rumen (p < 0.01), hindgut (p = 0.01) and total digestive tract (p < 0.01); protozoa abundance (p < 0.05); and water intake (p < 0.001). Exposure to cold temperature increased plasma T3 concentration (p < 0.05), CO2 production (p = 0.01), total VFA concentrations (p = 0.03) and estimated microbial output from the rumen (p = 0.03). The rate of wool growth increased (p < 0.01) due to cold treatment, but DM intake, DM digestibility and BW change were not affected. The results suggest that exposure of sheep to cold ambient temperatures reduces digesta retention time in the gastrointestinal tract, leading to a reduction in enteric methane yield. Further research is warranted to determine whether T3 could be used as an indirect selection tool for genetic selection of low enteric methane-producing ruminants.


Assuntos
Temperatura Baixa , Motilidade Gastrointestinal/fisiologia , Metano/metabolismo , Ovinos/fisiologia , Tri-Iodotironina/sangue , Ração Animal/análise , Animais , Masculino , Ovinos/sangue , Tri-Iodotironina/metabolismo , Lã/crescimento & desenvolvimento
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