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Coat color is a factor affecting heat tolerance in tropical ruminant and a particular coat color can determine which is more resilient to environmental changes. The aim of this study was to measure the level of adaptation of Morada Nova sheep with different coat color by using an Adaptability Index (AI). Adult ewes were used, including two different coat colors of Morada Nova sheep (red and white) with mean of body weight of 28.02 ± 5.70 kg and 31.47 ± 3.41 kg, respectively. Physiology parameters, hematology, electrolytes, acid-base status, mineral, renal functions, metabolites, enzymes, and proteins were measured. AI was designed using a multivariate approach (principal component analysis) to "weigh" the influence of each variable in the animal responses. The variables more important for adaptive aspects of Red Morada Nova were: haematology, electrolytes and acid-base status. The hemoglobin (HG), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), sodium (Na+), oxygen pressure (PO2), glucose (GLU) and albumin (ALB) were significantly higher in Red Morada Nova sheep and hydrogen carbonate (HCO3), base excess (BE), total carbon dioxide concentration (TCO2) and URE were significantly higher in the white phenotype. The variables more important for adaptive aspects of White Morada Nova sheep were: (K+), total protein (TP), PO2, HG, cholesterol (CHO), rectal temperature (RT) and glucose (GLU). Both phenotypes showed a high adaptation level, however, a higher value was generated for the Red Morada Nova sheep (81.97). This study concludes that both phenotypes of the Morada Nova sheep breed are well adapted to the climatic condition of the Brazilian tropical region using different adaptive mechanisms.

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SUMMARY: This study evaluated the morphology of alpacas skin. Biopsies were collected and samples were fixed in 10 % neutral buffered formalin for histological procedures. The sections were stained with hematoxylin and eosin, picrosirius red and Masson's trichrome. Types I, III and IV collagen were analyzed by immunohistochemistry. The derma presented sebaceous and sweat glands, as well as follicular groups with medullated fibers. Type I and type IV collagen were observed at epidermis and dermis as well as in glandular structures and hair follicles. The collagen III, was observed only in dermis.

Este estudio evaluó la morfología de la piel de alpacas. Se recogieron biopsias y las muestras se fijaron en formalina tamponada neutra al 10 % para procedimientos histológicos. Las secciones se tiñeron con hematoxilina y eosina, rojo picrosirius y tricrómico de Masson. El colágeno tipo I, III y IV se analizó mediante inmunohistoquímica. La dermis presentó glándulas sebáceas y sudoríparas, así como grupos foliculares con fibras medulares. Se observó colágeno tipo I y tipo IV en la epidermis y la dermis, así como en estructuras glandulares y folículos pilosos. El colágeno III, se observó únicamente en la dermis.

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This study's objective was to evaluate the thermoregulation aspects of native goats through broken-line regression to understand the triggering of physiological responses in the homeothermy process. Data were collected from ten healthy dams of the Canindé breed once a week at hourly intervals (24 h) for eight consecutive weeks. Air temperature (AT; °C), relative humidity (RH; %) were measured and temperature-humidity index (THI) calculated. The thermoregulation parameters evaluated were: respiratory rate (RR; breaths.min-1), rectal temperature (RT; °C) and sweating rate (SR; g.m-2.h-1). All variables were subjected to analysis of variance with repeated measures over time. The hour was considered a fixed effect (00:00 h, 01:00 h, …, 23:00 h), and the animal was a random effect. Multiple regression analyses were also examined using General Linear Models and Variance Inflation Factors were calculated. Broken line non-linear regressions for RR, RT and SR were examined using independent variables. The highest average for AT and RH were 35.9 °C (13:00 h) and 92.4% (04:00 h), respectively. The lowest average of TA and RH were 22.1 °C (05:00 h) and 28.0% (12:00 h), respectively. The highest average THI was 102.1 (13:00 h), and the lowest 78.0 (05:00 h). The environmental thresholds at which RR, RT and SR began to increase for AT were between 17-21 °C and RH were > 17% (RR), ≥ 21 (RT) and > 23% (SR). For THI the limits were 108.4 for RR, 78.0 for RT and 100.1 for SR. Using THI, the thermoregulatory parameters are activated in the following order: SR, RR and RT. Estimates can serve as a basis to implement heat stress mitigation and improve animal welfare strategies for native goats.

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Canine piroplasmid infections can be caused by Babesia spp., Theileria spp. and Rangelia vitalii. In Brazil, canine babesiosis caused by Babesia vogeli is endemic and reported throughout the country. On the other hand, Rangeliosis caused by R. vitalii has only been described so far in the South and Southeast regions. Despite that, studies analyzing the laboratory and molecular characterization of these hemoprotozoa are still scarce. To investigate the occurrence, the laboratory features, the molecular characterization, and the diversity of piroplasmids from Midwestern Brazil, a survey was performed using blood samples obtained from 276 domestic dogs from Brasília, Federal District, Midwestern Brazil. A broad-range quantitative PCR (qPCR) targeting the mitochondrial large subunit ribosomal DNA (LSU4) was used to detect piroplasmid DNA. The overall molecular occurrence of piroplasmids was 11.2% (31/276), with 9.7% (27/276) of the sequences identified as Babesia vogeli (98-100% identity to B. vogeli isolate from the USA). Based on a partial 18S rRNA sequence pairwise alignment (-250 bp), 1.4% (4/276) of the sequences showed only 76.8% identity with B. vogeli but 100% identity with opossum-associated Babesia sp. (MW290046-53). These findings suggest the exposure of dogs from Brazil to a recently described Babesia sp. isolated from white-eared opossum. None of the analyzed dogs was positive for Theileria spp. or R. vitalii. Subsequently, all positive sequences were submitted to three additional PCR assays based on the 18S rRNA, cox-1, and cytb genes, aiming at performing a haplotype network analysis. Haplotype network using cox-1 sequences showed the presence of six different haplotypes of B. vogeli; one of them was shared with isolates from Brazil, the USA, and India. When including animals co-infected with other vector-borne diseases, piroplasmid-positive dogs had 2.3 times higher chance of having thrombocytopenia than the negative ones. The molecular results demonstrated that the compared Babesia vogeli sequences showed a low variability as well as evidence of exposure to a putative novel opossum-associated Babesia sp. in dogs from Midwestern Brazil.

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The environment is vital to the agricultural sector since it can cause adversities throughout the entire productive chain. This study evaluated the geographical distribution of zebu breeds in Brazil and correlated their occurrence with environmental variables and the human development index. Herds of purebred zebu cattle (Bos indicus) in Brazil were classified as beef, dairy, and dual-purpose breeds, and all breeds were spatialized in the ArcGIS program. Environmental (precipitation, temperature, relative humidity index) and the human development index (HDI) were examined. We conducted regression and logistic analyses. Zebu cattle showed a lower distribution in the Northeastern states compared to other locations, possibly due to harsh weather conditions, namely long periods of high temperatures and lower precipitation, directly affecting local livestock. Beef breeds were evenly spread throughout the country in regions influenced by environmental variables of higher precipitation, normalized difference vegetation index (NDVI), temperature, relative humidity (RH), and temperature humidity index (THI), as well as properties without smallholder farmers and rivers and streams with riparian vegetation. The regions for dual-purpose and dairy breeds were predominantly cultivated with cutting forages (e.g., sugarcane - Saccharum officinarum), with the integration of crops, livestock and/or forestry (i.e., combining different activities in the same area) and areas with a rotational grazing system (i.e., grazing management), indicating a higher occupation in fertile lands. The Gir breed, the only dairy breed evaluated in this study, was seen in establishments with smallholder farmers, characterized by small to medium farms, and in regions at higher altitudes.

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Feed restriction (FR) occurs commonly in sheep production systems in the Brazilian semi-arid region and can cause physiological changes in the progeny. We assessed the effects of the FR pre and postnatal on the performance and carcass traits of Morada Nova lambs. Twenty-four lambs born from a group of 68 ewes were distributed in three treatments of 8 replicates as follows: ewes fed ad libitum pre and postnatal (AL-AL); postnatal restriction (POSTN-R): included lambs born from ewes fed ad libitum in the last third of pregnancy with FR postnatal; and prenatal feeding restriction (PREN-AL): comprised lambs born from ewes subjected to FR in the last third of pregnancy but ad libitum postnatal. Slaughter body weight (20.96 kg); total weight gain (11.34 kg); average daily weight (0.096 kg); fasting carcass weight (19.45); hot carcass weight (9.33 kg); and cold carcass weight (9.11 kg) were smaller (P < 0.05) in POSTN-R but similar between AL-AL and PREN-AL. Rib (0.47 kg), shoulder (0.85 kg), loin (0.50 kg), and chest-flank (0.97 kg) had lower weight in lambs under POSTN-R (P < 0.05). The treatments did not affect the tissue composition of the 12th rib. The non-carcass components and carcass traits are the variables that best discriminate animals under FR plans. The postpartum FR in native lambs has an impact on the performance and carcass weight of the progeny, unlike lambs submitted to prepartum FR, which demonstrates the adaptation to intrauterine nutritional deficiency in Morada Nova ewes to produce lambs with heavy carcasses in regions semi-arid.

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Feline piroplasmids include the genera Babesia spp., Cytauxzoon spp., and Theileria spp. In Brazil, there are few reports regarding these hemoprotozoans; however, clinicopathological and molecular data are scarce. This study aimed to characterize the clinical relevance of these parasites through hematological, biochemical, and molecular approaches. For this purpose, 166 cats from Brasilia, Federal District, Midwestern Brazil, were screened using a quantitative polymerase chain reaction (qPCR) for piroplasmids based on the LSU4 mitochondrial gene, which resulted in an overall prevalence of 36/166 (21.7%). Twelve of 166 samples (7.2%) were positive for C. felis, while 19/166 (11.4%) were positive for Babesia vogeli. No samples tested positive for Theileria spp. Babesia vogeli and Cytauxzoon spp. LSU4 sequences showed identities of 97-100% and 99.3%, respectively, to US isolates. The hematological and biochemical findings did not differ significantly between the cats that tested positive and negative for piroplasmids. Although the lack of abnormalities in clinical and laboratory parameters does not eliminate the possibility that these cats were sick and recovered, it may suggest that the Brazilian strain of Cytauxzoon spp. is not as pathogenic as that from the USA, despite the high molecular identity with North American isolates.

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ABSTRACT The aim of this study was to explore spatial genetic structure patterns in cattle breeds adapted to local conditions in Brazil. We georeferenced 876 animals of ten breeds raised in Brazil kept in the Genebank of Brazilian Agricultural Research Corporation (Embrapa) by sample locations using the QGIS 2.4.0 software. The Mantel tests, spatial autocorrelation, and Monmonier tests were performed. The distances for spatial correlation tests ranged from 5 to 15 classes. The results indicated genetic discontinuities in cattle breeds from the Midwest, South, and Southeast of the country. Correlation between genetic and geographic distance was low, but significant. The Monmonier Maximum Distance Algorithm indicated an initial subdivision of Curraleiro and then Pantaneiro from the other breeds. In another subdivision, Criollo, Mocho Nacional, and Caracu were grouped. Genetic discontinuity was observed beyond 431 km, the minimum sampling distance between populations for conservation purposes.

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The aim of this study was to explore spatial genetic structure patterns in cattle breeds adapted to local conditions in Brazil. We georeferenced 876 animals of ten breeds raised in Brazil kept in the Genebank of Brazilian Agricultural Research Corporation (Embrapa) by sample locations using the QGIS 2.4.0 software. The Mantel tests, spatial autocorrelation, and Monmonier tests were performed. The distances for spatial correlation tests ranged from 5 to 15 classes. The results indicated genetic discontinuities in cattle breeds from the Midwest, South, and Southeast of the country. Correlation between genetic and geographic distance was low, but significant. The Monmonier Maximum Distance Algorithm indicated an initial subdivision of Curraleiro and then Pantaneiro from the other breeds. In another subdivision, Criollo, Mocho Nacional, and Caracu were grouped. Genetic discontinuity was observed beyond 431 km, the minimum sampling distance between populations for conservation purposes.

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The aim of this study was to explore spatial genetic structure patterns in cattle breeds adapted to local conditions in Brazil. We georeferenced 876 animals of ten breeds raised in Brazil kept in the Genebank of Brazilian Agricultural Research Corporation (Embrapa) by sample locations using the QGIS 2.4.0 software. The Mantel tests, spatial autocorrelation, and Monmonier tests were performed. The distances for spatial correlation tests ranged from 5 to 15 classes. The results indicated genetic discontinuities in cattle breeds from the Midwest, South, and Southeast of the country. Correlation between genetic and geographic distance was low, but significant. The Monmonier Maximum Distance Algorithm indicated an initial subdivision of Curraleiro and then Pantaneiro from the other breeds. In another subdivision, Criollo, Mocho Nacional, and Caracu were grouped. Genetic discontinuity was observed beyond 431 km, the minimum sampling distance between populations for conservation purposes.(AU)

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This study was realized to analyze the combinations of climatic, physical, and socio-economic variables on distribution of breeding values for performance characteristics and scrotal circumference of Brangus cattle. Records of 84,703 Brangus animals, born from 2000 to 2010 distributed in 65 farms in Brazil were used. The characteristics analyzed were average daily gain from birth to weaning and from weaning to yearling (WW and YW), visual scores of conformations (WC and YC), muscle score (WM and YM), precocity score (WP and YS), and size score (WS and YS) at weaning and yearling and scrotal circumference (SC) at yearling. Components of (co)variance estimated through the animal model employing methodology to AIREML. Mean estimates of direct heritability obtained for visual scores at weaning (WC 0.16, WM 0.16, WP 0.19, and WS 0.22) were lower than those obtained at yearling (YC 0.28, YM 0.26, YP 0.24, and YS 0.40). WW had heritability greater than YW (0.27 and 0.12) and a heritability of 0.36 obtained for SC. Canonical, discriminant, and cluster analyses were performed in the SAS® 9.4 program. Three clusters of genetic values averages per farm were formed according to climatic, physical, and socio-economic variables. Brangus animals are from states of RS, PR, SP, MG, GO, MG, and MS. The highest breeding values were strongly related to thermal amplitude and municipality area. Spatial distribution of the breeding value of Brangus animals can help in the development of environmental indices, genetic evaluations, and the choice of animals for certain environments.

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There are few animal germplasm/gene bank collections in Brazil, and basic studies are needed to attend the future internal and external demands from international partners. The aim of this work was to validate a "proof of concept" that integrates spatial (georeferenced data) and genetic data regarding the local of origin from 3518 DNA samples from 17 different genetic groups or breeds of sheep in the Brazilian Germplasm bank. Spatialisation shows that not all genetic groups have samples in the bank, and collection is concentrated in the conservation nuclei spread nationwide. Only 21% of states with a specific breed have samples in the gene bank. The mean number of animals sampled per collection was 32, while the mean distance travelled to collect samples was 262 km from the conservation nuclei. For example, the Brazilian Somali were only collected in the conservation nucleus in Ceará State. No samples were collected to date for the Cariri breed, which is recognised by the Brazilian Ministry of Agriculture. Only two farms and one breed in the bank are from the northern region. Of the 27 states, there are samples in the gene bank of sheep from 13, so several states have no samples, requiring collection from herds outside the official system of conservation to make sure that studies using this germplasm realised are not biased. Significant genetic differences are seen above 332 km, which should guide future sampling efforts. Suggestions are given for improving the quantity, quality and diversity of samples in the gene bank.

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Bos taurus taurus and Bos taurus indicus cattle subspecies present different capabilities in coping with situations of elevated temperatures, the latter being more tolerant to heat stress. Thus, some breeding programs crossed these subspecies to produce a high producing yet heat-tolerant breed (Girolando). Nineteen Holstein (H100) and 19 Girolando cows [(½ Holstein × Gir (H50) and ¾ Holstein × Gir (H75)] with similar milk production were used in a six-day experiment to evaluate the consequences of heat stress due to shade deprivation on their physiological, blood and milk traits. Cows were exposed to a non-shaded environment between morning (06:00h; GMT -3:00) and evening milking (14:30h; GMT -3:00) with access to water ad libitum. Procedures were conducted before morning and evening milkings. Physiological parameters related to mechanisms of heat dissipation were measured, as well as the milk composition. Blood traits were evaluated. The temperature-humidity index (THI) was calculated. Statistical procedures included analysis of variance, correlation, and principal factors. THI was elevated during the trial and negatively impacted physiological, milk, and blood parameters in H100, H75, and H50. Alterations in physiology, milk stability, milk composition, and blood traits were more pronounced in H100. Holstein cows presented changes in physiological parameters in a more pronounced manner and in some milk and blood traits related to the reduced capability of this breed in dealing with elevated THI. The similarity in milk production levels excludes this parameter as a justification for differences in heat tolerance, with genetic composition being the main reason for these results.

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Bos taurus taurus and Bos taurus indicus cattle subspecies present different capabilities in coping with situations of elevated temperatures, the latter being more tolerant to heat stress. Thus, some breeding programs crossed these subspecies to produce a high producing yet heat-tolerant breed (Girolando). Nineteen Holstein (H100) and 19 Girolando cows [(½ Holstein × Gir (H50) and ¾ Holstein × Gir (H75)] with similar milk production were used in a six-day experiment to evaluate the consequences of heat stress due to shade deprivation on their physiological, blood and milk traits. Cows were exposed to a non-shaded environment between morning (06:00h; GMT -3:00) and evening milking (14:30h; GMT -3:00) with access to water ad libitum. Procedures were conducted before morning and evening milkings. Physiological parameters related to mechanisms of heat dissipation were measured, as well as the milk composition. Blood traits were evaluated. The temperature-humidity index (THI) was calculated. Statistical procedures included analysis of variance, correlation, and principal factors. THI was elevated during the trial and negatively impacted physiological, milk, and blood parameters in H100, H75, and H50. Alterations in physiology, milk stability, milk composition, and blood traits were more pronounced in H100. Holstein cows presented changes in physiological parameters in a more pronounced manner and in some milk and blood traits related to the reduced capability of this breed in dealing with elevated THI. The similarity in milk production levels excludes this parameter as a justification for differences in heat tolerance, with genetic composition being the main reason for these results.(AU)

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Traditional livestock productivity is hard to estimate, since it depends on a gamut of animal production indicators that are difficult to measure for many farms. Thus, we propose an analytical method for estimating productivity and understanding the importance of animal production indicators under different full-cycle cattle production systems in Brazil. To evaluate the impact of these indicators, equations were derived from a comutational model of herd evolution for estimating the output parameters of the system as follows: productivity per hectare (PH) and offtake rate (COR), as a function of the indicators; calving rate (CR), mating age (AM), age of slaughter (AS) and stocking rate (SR). For this analysis, twenty-seven scenarios (simulation data) of low to high productivity were used, resulting from the combination of the following factors and levels: 1) calving rate of 50, 65 and 80 %; 2) mating age of heifers of one, two and three, years of age; and 3) age at slaughter of one, two and three year old steers. The scenario with the highest impact for each parameter and the indicator of highest impact for each scenario were identified for the production conditions in the region. Under most scenarios, a reduction in mating age had a greater impact on the productivity indexes compared to a reduction in slaughter age. Appropriate management of available technologies enables farmers to compare the marginal impacts of specific indicators on full-cycle production systems for beef cattle.(AU)

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Traditional livestock productivity is hard to estimate, since it depends on a gamut of animal production indicators that are difficult to measure for many farms. Thus, we propose an analytical method for estimating productivity and understanding the importance of animal production indicators under different full-cycle cattle production systems in Brazil. To evaluate the impact of these indicators, equations were derived from a comutational model of herd evolution for estimating the output parameters of the system as follows: productivity per hectare (PH) and offtake rate (COR), as a function of the indicators; calving rate (CR), mating age (AM), age of slaughter (AS) and stocking rate (SR). For this analysis, twenty-seven scenarios (simulation data) of low to high productivity were used, resulting from the combination of the following factors and levels: 1) calving rate of 50, 65 and 80 %; 2) mating age of heifers of one, two and three, years of age; and 3) age at slaughter of one, two and three year old steers. The scenario with the highest impact for each parameter and the indicator of highest impact for each scenario were identified for the production conditions in the region. Under most scenarios, a reduction in mating age had a greater impact on the productivity indexes compared to a reduction in slaughter age. Appropriate management of available technologies enables farmers to compare the marginal impacts of specific indicators on full-cycle production systems for beef cattle.

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Samples of 191 animals from 18 different Brazilian locally adapted swine genetic groups were genotyped using Illumina Porcine SNP60 BeadChip in order to identify selection signatures related to the monthly variation of Brazilian environmental variables. Using BayeScan software, 71 SNP markers were identified as FST outliers and 60 genotypes (58 markers) were found by Samßada software in 371 logistic models correlated with 112 environmental variables. Five markers were identified in both methods, with a Kappa value of 0.073 (95% CI: 0.011-0.134). The frequency of these markers indicated a clear north-south country division that reflects Brazilian environmental differences in temperature, solar radiation, and precipitation. Global spatial territory correlation for environmental variables corroborates this finding (average Moran's I = 0.89, range from 0.55 to 0.97). The distribution of alleles over the territory was not strongly correlated with the breed/genetic groups. These results are congruent with previous mtDNA studies and should be used to direct germplasm collection for the National gene bank.

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The first horses were brought to Brazil by the colonizers after 1534. Over the centuries, these animals evolved and adapted to local environmental conditions usually unsuitable for exotic breeds, thereby originating locally adapted Brazilian breeds. The present work represents the first description of maternal genetic diversity in these horse breeds based on D-loop sequences. A D-Loop HSV-I fragment of 252 bp, from 141 horses belonging to ten Brazilian breeds / genetic groups (locally adapted and specialized breeds) were analysed. Thirty-five different haplotypes belonging to 18 haplogroups were identified with 33 polymorphic sites. Haplotype diversity (varying from 0.20 to 0.96) and nucleotide diversity (varying from 0.0039 to 0.0239) was lower for locally adapted than for specialized breeds, with the same pattern observed for FST values. Haplogroups identified in Brazilian breeds are in agreement with previous findings in South American samples. The low variability observed mainly in locally adapted breeds, indicates that, to ensure conservation of these breeds, careful reproductive management is needed. Additional genetic characterization studies are required to support accurate decision-making.

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Abstract The first horses were brought to Brazil by the colonizers after 1534. Over the centuries, these animals evolved and adapted to local environmental conditions usually unsuitable for exotic breeds, thereby originating locally adapted Brazilian breeds. The present work represents the first description of maternal genetic diversity in these horse breeds based on D-loop sequences. A D-Loop HSV-I fragment of 252 bp, from 141 horses belonging to ten Brazilian breeds / genetic groups (locally adapted and specialized breeds) were analysed. Thirty-five different haplotypes belonging to 18 haplogroups were identified with 33 polymorphic sites. Haplotype diversity (varying from 0.20 to 0.96) and nucleotide diversity (varying from 0.0039 to 0.0239) was lower for locally adapted than for specialized breeds, with the same pattern observed for FST values. Haplogroups identified in Brazilian breeds are in agreement with previous findings in South American samples. The low variability observed mainly in locally adapted breeds, indicates that, to ensure conservation of these breeds, careful reproductive management is needed. Additional genetic characterization studies are required to support accurate decision-making.

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ABSTRACT: Wharton's jelly is a source of mesenchymal stem cells (MSCs) that had not yet been tested for bovine embryo production by nuclear transfer (NT). Thus, the objective of this study was to isolate, characterize and test MSCs derived from Wharton's jelly for embryo and pregnancy production by NT in cattle. The umbilical cord was collected during calving and cells derived from Wharton's jelly (WJCs) were isolated by explant and cultured in Dulbecco's Modified Eagle Medium. Skin Fibroblasts (FB) were isolated after 6 months of life. Morphological analysis was performed by bright field and scanning electron microscopy (SEM) during cell culture. Phenotypic and genotypic characterization by flow cytometry, immunocytochemistry, RT-PCR and differentiation induction in cell lineages were performed for WJC. In the NT procedure, oocytes at the arrested metaphase II stage were enucleated using micromanipulators, fused with WJCs or FB and later activated artificially. SEM micrographs revealed that WJCs have variable shape under culture. Mesenchymal markers of MSCs (CD29+, CD73+, CD90+ and CD105+) were expressed in bovine-derived WJC cultures, as evidenced by flow cytometry, immunocytochemistry and RT-PCR. When induced, these cells differentiated into osteocytes, chondrocytes and adipocytes. After classification, the WJCs were used in NT. Blastocyst formation rate by NT with WJCs at day 7 was 25.80±0.03%, similar to blatocyst rate with NT using skin fibroblasts (19.00±0.07%). Pregnancies were obtained and showed that WJCs constitute a new cell type for use in animal cloning.

RESUMO: A geleia de Wharton é uma fonte de células tronco mesenquimais (CTMs) que ainda não havia sido testada para a produção de embriões bovinos por transferência nuclear (TN). O objetivo deste estudo foi isolar, caracterizar e testar as CTMs derivadas da geleia de Wharton para produção de embriões e gestações por transferência nuclear em bovinos. O cordão umbilical foi coletado durante o nascimento e as células derivadas da geleia de Wharton (CGWs) foram isoladas por explante e cultivadas em Dulbecco's Modified Eagle Medium. Fibroblastos (FB) da pele foram isolados após 6 meses de vida. As análises morfológicas foram realizadas pelas microscopias de campo claro e eletrônica de varredura durante o cultivo celular. Caracterização fenotípica e genotípica por citometria de fluxo, imunocitoquímica, RT-PCR e indução da diferenciação em linhagens celulares foi realizada com as CGWs. No procedimento de TN, ovócitos no estágio de metáfase II foram enucleados usando micromanipuladores, fusionados com CGWs ou FB e então ativados artificialmente. Micrografias de microscopia de varredura revelaram que CGWs tiveram forma variada sob cultivo. Os marcadores mesenquimais de CTMs (CD29+, CD73+, CD90+ and CD105+) foram expressos em cultura de CGWs bovina, como evidenciado por citometria de fluxo, imunocitoquímica e RT-PCR. Quando induzidas, estas células diferenciaram-se em osteócitos, condrócitos e adipócitos. Após classificação, as CGWs foram utilizadas na TN. A taxa de formação de blastocistos por TN com CGWs no sétimo dia de cultivo foi de 25,80±0,03%, similar a produção de blastócitos por TN com fibroblastos de pele (19,00±0,07). Gestações foram obtidas e mostraram que CGWs constituem um novo tipo celular para ser usado na clonagem animal.