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At least 145 records · Page 8Linked to original sources
PubMed2003

Research on the genetic variations of a1-fucosytransferase (FUT1) gene in 26 pig breeds.

Enterotoxigenic Escherichia coli F18(ECF18) is a main pathogen that causes edema disease and post-weaning diarrhoea in piglets, and al-fucosytransferase (FUT1) gene has been identified as a candidate gene for controlling the expression of the receptor for ECF18 bacteria. The genetic variations at position 307 nucleotide in open reading frame of FUT1 gene in 26 pig breeds (total 1458 individuals) from 5 western commercial pig breeds and 21 Chinese native pig breeds were investigated by PCR-RFLP. The results showed that the genetic polymorphisms of the FUT1 locus were only detected in 5 western pig breeds and the Chinese Lingao pig breed, 5 western pig breeds possessed 3 different genotypes, and Lingao pig breed had two susceptible genotypes GG and AG, while all the other 20 Chinese native pig breeds only presented the susceptible genotype GG. The results indicated that if M307G-A point mutation in the coding region of FUT1 gene was the key factor determining the expression of the ECF18 receptor, most of Chinese native pig breeds were absent of the genetic background on the resistance to ECF18 bacteria. In this case, it was inferred that the resistance gene to ECF18 might be originated from western pig breeds. In addition, it is of great importance for the conservation of Lingao pig breed as it is the only found Chinese native pig breed possessing resistance M307A allele in FUT1 gene. Generally, compared with exotic pig breeds, Chinese native pig breeds have stronger resistance to edema disease and post-weaning diarrhoea in piglets. The results suggested that further study should be done to identify and characterize putative QTL (quantitative trait locus) or/and the functional gene responsible for the resistance to ECF18 in Chinese native pig breeds.

Alleles↗
PubMedDate not supplied

Genetic variability of six French meat sheep breeds in relation to their genetic management.

Some demographic parameters, the genetic structure and the evolution of the genetic variability of six French meat sheep breeds were analysed in relation with their management. Four of these breeds are submitted to more or less intense selection: the Berrichon du Cher (BCH), Blanc du Massif Central (BMC), Charollais (CHA) and Limousin (LIM); the other two breeds are under conservation: the Roussin de La Hague (RLH) and Solognot (SOL). Genealogical data of the recorded animals born from 1970 to 2000 and of their known ancestors were used. The most balanced contributions of the different flocks to the sire-daughter path was found in the SOL. In the BCH, a single flock provided 43% of the sire-AI sire path, whereas the contributions of the flocks were more balanced in the BMC and LIM (the only other breeds where AI is used to a substantial amount). The distribution of the expected genetic contribution of the founder animals was found to be unbalanced, especially in the BCH and LIM. The effective numbers of ancestors (founders or not) for the ewes born from 1996 to 2000 were equal to 35 (BCH), 144 (BMC), 112 (CHA), 69 (LIM), 40 (RLH) and 49 (SOL). Inbreeding was not analysed in the BMC, due to incomplete pedigree information. From 1980 on, the rates of inbreeding, in percentage points per year, were +0.112 (BCH), +0.045 (CHA), +0.036 (LIM), +0.098 (RLH) and +0.062 (SOL). The implications of the observed trends on genetic variability are discussed in relation to the genetic management of each breed. The need for a larger selection basis in the BCH, the efficiency of the rules applied in the SOL to preserve the genetic variability and the need for a more collective organisation in the CHA and RLH are outlined.

Animals↗
PubMed2026

Characterization of a draft chromosome-scale genome assembly for the mutton snapper, Lutjanus analis.

BACKGROUND: The mutton snapper (Lutjanus analis) is a reef fish commonly found in tropical waters of the Western Atlantic Ocean. Genomic studies of this species are needed to support conservation efforts and breeding programs. OBJECTIVE: Here, we report the development of a chromosome-scale reference assembly for the mutton snapper and conduct an initial comparative genomic analysis with other lutjanids. METHODS: The genome of one mutton snapper specimen was sequenced using PAC-Bio HiFi long reads and Illumina short reads. Contigs and scaffolds were assembled in the Flye pipeline and anchored using Hi-C proximity guided assembly. Gene prediction and functional annotations were obtained in AUGUSTUS and eggNOG-mapper, respectively. The mutton snapper genome was compared to those of other lutjanids to infer gene family evolution and chromosome synteny conservation. RESULTS: Assembly and polishing yielded 946 contigs and 926 scaffolds (N50 of 3.16 Mb, complete BUSCO score 98.1%) that were anchored using Hi-C scaffolding in 24 draft chromosomes. The anchored assembly featured a N50 of 42.47 Mb and contained 97.6% of the unanchored assembly length. The 24 mutton snapper chromosomes showed a one-to-one syntenic relationship with their counterparts in medaka, and other Lutjanids. AUGUSTUS predicted 29,023 genes, 24,335 of which (83.85%) could be functionally annotated. Gene family evolution analysis revealed 1,014 significantly expanded or contracted hierarchical ortholog groups in mutton snapper. Expansions and contractions were linked to several biological functions including growth, oocyte maturation, and response to exogenous stressors. CONCLUSION: The draft genome will be a valuable tool for forthcoming applied genomic studies of mutton snapper.

Animals↗
PubMed2025

Near-complete reference genome assembly of Hoya carnosa.

Hoya R. Br. is the largest genus in the tribe Marsdenieae (Apocynaceae), comprising 350-450 species. Hoya species are popular in horticulture for their distinctive floral traits and fragrances, primarily sourced from domestication and mutation breeding. However, the lack of molecular analysis for floral morphological traits has limited their cultivation and application. In this study, we assembled a near-complete reference genome for H. carnosa, the model species of the genus, using PacBio HiFi reads and Hi-C method. The genome size was approximately 465.7 Mb with a contig N50 of 39.3 Mb. 99.7% of the sequences were anchored to 11 pseudochromosomes, and the assembly achieved a BUSCO score of 98.5%. We predicted 24,309 protein-coding genes, of which 90.2% (21,927) were functionally annotated. This high-quality genome provides a valuable reference for the research of evolution, conservation and molecular breeding in Hoya.

Genome, Plant↗
PubMed2005

Conservation programmes for African cattle: design, cost and benefits.

Information on costs and benefits of conservation programmes for cattle is scarce in the literature and mainly available for Europe. This study aims at simulating cost of and benefits from different kinds of conservation programmes designed for indigenous African cattle. The programmes include installation of a herdbook and activities to promote the breed (HB), in situ conservation with a sire rotation scheme (IS), cryoconservation of semen (CC) and CC combined with in situ conservation (IC). The results indicate that cost of the analysed conservation programmes was generally higher than those reported in the literature for comparable schemes. If cost per effective population size conserved is considered, programmes analysed in this study do not appear to be more expensive. The proposed rotation scheme in IS can be applied to many different production systems and prove to be effective with regard to low increase in kinship. Reduction in extinction probability is found to be higher for conservation programmes that strongly involve farmers and give them part of the responsibility for the breeding population. IC was most efficient with regard to cost per effective population size conserved. However, if cost per reduction in endangerment is considered as criterion for the efficiency of a programme, IS, HB and CC are superior to IC. These findings suggest that decisions on conservation programmes should be based on multiple criteria, and not just on cost per effective population size.

Africa↗
PubMed2024

Mitochondrial DNA control-region and coding-region data highlight geographically structured diversity and post-domestication population dynamics in worldwide donkeys.

Donkeys (Equus asinus) have been used extensively in agriculture and transportations since their domestication, ca. 5000-7000 years ago, but the increased mechanization of the last century has largely spoiled their role as burden animals, particularly in developed countries. Consequently, donkey breeds and population sizes have been declining for decades, and the diversity contributed by autochthonous gene pools has been eroded. Here, we examined coding-region data extracted from 164 complete mitogenomes and 1392 donkey mitochondrial DNA (mtDNA) control-region sequences to (i) assess worldwide diversity, (ii) evaluate geographical patterns of variation, and (iii) provide a new nomenclature of mtDNA haplogroups. The topology of the Maximum Parsimony tree confirmed the two previously identified major clades, i.e. Clades 1 and 2, but also highlighted the occurrence of a deep-diverging lineage within Clade 2 that left a marginal trace in modern donkeys. Thanks to the identification of stable and highly diagnostic coding-region mutational motifs, the two lineages were renamed as haplogroup A and haplogroup B, respectively, to harmonize clade nomenclature with the standard currently adopted for other livestock species. Control-region diversity and population expansion metrics varied considerably between geographical areas but confirmed North-eastern Africa as the likely domestication center. The patterns of geographical distribution of variation analyzed through phylogenetic networks and AMOVA confirmed the co-occurrence of both haplogroups in all sampled populations, while differences at the regional level point to the joint effects of demography, past human migrations and trade following the spread of donkeys out of the domestication center. Despite the strong decline that donkey populations have undergone for decades in many areas of the world, the sizeable mtDNA variability we scored, and the possible identification of a new early radiating lineage further stress the need for an extensive and large-scale characterization of donkey nuclear genome diversity to identify hotspots of variation and aid the conservation of local breeds worldwide.

Animals↗
PubMedDate not supplied

Physiological effects of a fish oil supplement on captive juvenile tuatara (Sphenodon punctatus).

Tuatara (Sphenodon, Order Sphenodontia) are rare New Zealand reptiles whose conservation involves captive breeding. Wild tuatara eat seabirds, which contain high levels of the long-chain n-3 polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These fatty acids are absent from the captive diet, and consequently, plasma fatty acid composition of wild and captive tuatara differs. This study investigated the effects of incorporating EPA and DHA into the diet of captive juvenile tuatara (Sphenodon punctatus) in an attempt to replicate the plasma fatty acid composition of wild tuatara. Tuatara receiving a fish oil supplement containing EPA and DHA showed overall changes in their plasma fatty acid composition. Phospholipid EPA and DHA increased markedly, reaching 10.0% and 5.9 mol%, respectively, by 18 mo (cf. </=0.9% in controls). A reduced dosage from 18 to 24 mo probably still provided a higher n-3 PUFA content than the diet of wild juveniles. The fish oil supplement had no significant effects over 2 yr on growth rate, food conversion efficiency, or metabolism compared with controls; all juveniles survived and grew. Further study is required to determine whether a fish oil supplement would have long-term benefits for captive tuatara.

Animal Nutritional Physiological Phenomena↗
PubMed2006

Genetic relationship of Chinese and Japanese gamecocks revealed by mtDNA sequence variation.

Cockfighting has a very long history dating back to as early as 2500 years ago in China. Cockfighting was intertwined with human cultural traditions, helped disperse chickens across the world, and influenced the subsequent breed selection. Therefore, tracing the origin of gamecocks could mirror the distribution of the cockfighting culture. In this study, we compared the available mtDNA control region sequences in Chinese and Japanese gamecocks to test the recently proposed hypothesis behind the dual origin of the Japanese cockfighting culture (from China and Southeast Asia independently). We assigned gamecock mtDNAs to different matrilineal components (or phylogenetic clades) that emerged from the phylogenetic tree and network profile, and compared the frequency differences between Chinese and Japanese gamecocks. Among the six clades (A-F) identified, Japanese gamecocks were most frequently found in clades C and D (74%, 32/43), whereas more than half of the Chinese gamecock samples (69%, 35/51) were grouped in clades A and B. Haplotypes in Japanese gamecocks assigned to clades A, B, and E were either shared with those of the Chinese samples or differed from the close Chinese types by no more than a three-mutation distance. This genetic pattern is in accordance with the proposed dual origin of Japanese gamecocks but has left room for single origin of Japanese gamecocks from China. The genetic structure of gamecocks in China and Japan might also be influenced by subsequent breed selection and conservation after the initial gamecock introduction.

Animals↗
PubMed1996

Low blood protein heterozygosity in zoo-bred hamadryas baboons.

An electrophoretic study of erythrocyte allozymes and serum proteins representing 32 genetic loci in 32 hamadryas baboons (Papio H.hamadryas) from Cologne and Frankfurt zoos revealed biallelic polymorphism in phosphoglucomutase (PGM), mannose phosphate isomerase (MPI) and transferrin (Tf). Polymorphism amounted to P = 0.097 over 31 loci and observed heterozygosity to H(o) = 0.011, indicating significant reduction from the respective gene diversity parameters encountered in free-living hamadryas baboons. Polygynous mating reduced numbers of heterozygotes at the Tf and the PGM-II loci significantly below Hardy-Weinberg expectations. This results support the importance of active genetic management in programmes for captive breeding and species conservation.

Alleles↗
PubMed2004

Towards an embryocentric world: the current and potential uses of embryo technologies in dairy production.

Structural features of the dairy industry make it well situated to use embryo technologies as tools for enhancing the genetic merit of dairy cattle and improving fertility. Technologies dependent upon embryo transfer have the potential to increase the efficiency of quantitative genetic selection as well as marker-assisted selection, simplify cross-breeding and germplasm conservation procedures and allow incorporation of transgenes into dairy cattle. In addition, embryo technologies may prove useful in improving fertility in infertile populations of lactating cows. The realisation of the promise of embryo technologies has been constrained by suboptimal efficiency in the production of embryos, alterations in embryonic and fetal survival and development associated with in vitro embryo production and cloning, as well as other technical and societal concerns. Solutions to many of these constraints are possible and the use of embryo technologies in both nucleus and commercial herds is likely to increase. Eventually, embryo transfer may compete with artificial insemination as a dominant method for establishing pregnancies in dairy cattle.

Animals↗
PubMedDate not supplied

Juvenile Siberian hamsters display torpor and modified locomotor activity and body temperature rhythms in response to reduced food availability.

Siberian hamsters as young as 16 and 28 d displayed torpor in response to treatment with 2,500 mg/kg 2-deoxy-D-glucose and reduced food availability, respectively. In addition, most food-restricted hamsters displayed increased locomotor activity and elevated body temperatures in the 3 h immediately preceding daily food delivery. This anticipatory activity disappeared within a few days of reimposition of ad lib. feeding. Torpor first appeared spontaneously at approximately 13 wk of age in hamsters fed ad lib. and maintained in short day lengths. The onset of this "spontaneous" torpor was unaffected by the hamsters' history of food restriction before age 2 mo. Siberian hamsters born late in the breeding season can conserve energy by undergoing torpor immediately after weaning when they contend with food shortages and concurrent energetic challenges imposed by growth requirements and low ambient temperatures.

Analysis of Variance↗
PubMed2026

Identification and characterization of the HSP gene family in the Chinese giant salamander: Expression patterns under combined environmental stress.

BACKGROUND: The Chinese giant salamander (Andrias davidianus) is a critically endangered living fossil species that is highly sensitive to changes in water temperature. However, systematic studies on the heat shock protein (HSP) gene family and its response mechanisms to environmental stress in this species remain limited. This study utilized transcriptome data from captive-bred salamanders exposed to combined temperature and pathogen stress. Bioinformatics tools were employed to identify the HSP gene family of A. davidianus (AndHSP) and to analyze their evolution, structure, and function, thereby revealing their regulatory mechanisms in response to environmental stress. RESULTS: A total of 72 AndHSPs were identified and classified into five subfamilies. Phylogenetic analysis revealed that each subfamily is evolutionarily conserved and functionally related. Gene expression analysis demonstrated that pathogen infection induced the expression of AndHSPs, and elevated temperature significantly intensified this response. Nine key differentially expressed genes were identified, predominantly from the AndHSP70 subfamily, with AndHSP70-18 exhibiting rapid heat-induced expression. Tissue-specific analysis showed high expression of AndHSP60 in the spleen. A qPCR validation confirmed the reliability of the transcriptome expression results. CONCLUSIONS: This study presents the first systematic identification of the AndHSP gene family and elucidates its cooperative stress response mechanisms under combined temperature and pathogen stress. These findings provide a molecular basis for understanding the species' environmental adaptation and have important implications for its conservation and artificial breeding.

Animals↗
PubMed2005

Biotechnology of temperate fruit trees and grapevines.

Challenges concerning fruit trees and grapevines as long lived woody perennial crops require adapted biotechnological approaches, if solutions are to be found within a reasonable time frame. These challenges are represented by the need for correct identification of genetic resources, with the foreseen use either in conservation or in breeding programmes. Molecular markers provide most accurate information and will be the major solution for questions about plant breeders rights. Providing healthy planting material and rapid detection of newly introduced pathogens by reliable methods involving serological and molecular biological tools will be a future challenge of increases importance, given the fact that plant material travels freely in the entire European Union. But also new breeding goals and transgenic solutions are part of the biotechnological benefits, e.g. resistance against biotic and abiotic stress factors, modified growth habits, modified nutritional properties and altered processing and storage qualities. The successful characterization of transgenic grapevines and stone fruit trees carrying genes of viral origin in different vectors constructed under ecological consideration, will be presented. Beyond technical feasibility, efficiency of resistance, environmental safety and Intellectual Property Rights, also public acceptance needs consideration and has been addressed in a specific project. The molecular determination of internal quality parameters of food can also be addressed by the use of biotechnological tools. Patient independent detection tools for apple allergens have been developed and should allow to compare fruits from different production systems, sites, and genotypes for their content of health threatening compounds.

Animals↗
PubMed1980

Canine parvovirus infection in South American canids.

Canine parvovirus (CPV) infections occurred in 5 of 35 South American canids at the Department of Conservation (DC), a breeding facility of the National Zoological Park in Front Royal, Va. The clinical signs were anorexia, lethargy, diarrhea, and vomiting. Three of the affected canids survived and had high hemagglutination-inhibition titers to CPV in the recovery period. Necropsy of the 2 that died revealed extensive necrosis of the intestinal mucosa; CPV particles were observed by electron microscopy in the intestinal contents of both animals. Six of the 30 canids that remained healthy had high hemagglutination-inhibition titers to CPV prior to the episode of illness, indicating earlier subclinical exposure. Pet dogs belonging to DC personnel that were screened as a possible source of the infection had no evidence of disease. All canids (including pet dogs) on the DC grounds were vaccinated repeatedly with a killed feline panleukopenia virus product after the episode, with little or no effect on existing titers.

Animals↗
PubMedDate not supplied

[Preservation of genetic variation in domestic animals using biotechnical methods].

The conservation of endangered breeds as live animals is at present the main national strategy of the government and breeding organizations to maintain genetic diversity. Fourty-three breeds and some old strains of cattle, pig, sheep, goat and horses are currently involved. Cryopreservation and banks for sperm, embryos or DNA are another type of genetic material which could subsequently be used for breeding and production in agriculture. Present semen banks involve 9 endangered cattle breeds and also a small amount of deep-frozen sperm of some endangered sheep and horse breeds. Only 2 embryo banks are established in government projects for cattle breeds Murnau-Werdenfelser and the old type German black-white cattle.

Animals↗
PubMed2005

Salmonellosis in pigmy hogs (Sus salvanius)--a critically endangered species of mammal.

The pigmy hog (Sus salvanius) is the smallest and the rarest wild suid in the world. This species is on the verge of extinction and the World Conservation Union has rated it among the most endangered of all mammals. This paper reports the investigation into an outbreak of salmonellosis among captive pigmy hogs at the Research and Breeding Centre of the pigmy hog conservation programme, Guwahati, Assam, India. Of 75 pigmy hogs (38 males and 37 females) maintained at the Centre, seven (9.3%) died within five days. The causative organism associated with the outbreak was identified as Salmonella Typhimurium (syn. S. enterica serovar Typhimurium). All the isolates of S. Typhimurium belonged to phage type DT193. The isolates harboured multiple plasmids. Five isolates harboured four (65.0 MDa, 4.2 MDa, 3.0 MDa, 1.3 MDa), while two isolates carried three plasmids (65.0 MDa, 4.2 MDa, 3.0 MDa). All strains showed resistance to amikacin, ampicillin, streptomycin and sulfamerazin; five strains were resistant to oxytetracycline and trimethoprim. All the strains were sensitive to chloramphenicol, ciprofloxacin, enrofloxacin and gentamicin. All seven isolates of S. Typhimurium were found to harbour stn, sopB and pefA genes. However, none of them was found to carry sefC and sopE genes.

Animals↗
PubMed2026

Genome-Wide Differentiation, Inbreeding, and Candidate Selection Loci in Local Vietnamese Pig Breeds.

Vietnam harbors exceptional genetic diversity among at least 26 indigenous pig breeds. We analyzed genome-wide single-nucleotide polymorphism (SNP) data from 90 animals representing 15 local Vietnamese breeds and six Landrace pigs using principal component analysis, the windowed fixation index (FST), cross-population extended haplotype homozygosity (XP-EHH), within-population integrated haplotype score (iHS), and runs of homozygosity (ROHs). The population structure was consistent with a north-south differentiation axis, and Ba Xuyen showed elevated heterozygosity, providing suggestive evidence of a European genetic contribution; the f3 statistic was positive (f3 = +0.015), and formal evidence of admixture requires a significantly negative f3, so this criterion was not met. Integration of FST and XP-EHH identified GPC5, E2F6, NOS1, and TLR4 as top Northern candidate loci and CRYM/ZP2 as the leading Central candidate locus, and these windows were recovered at both the 90th and 95th percentile thresholds, indicating analytical robustness rather than independent biological validation. iHS was elevated at E2F6 in Northern breeds (|iHS| = 3.04) and at NOS1 across all regional groups (|iHS| = 2.66-3.36). Breed-level phenotypic XP-EHH, based on published breed descriptions and coat color rather than individual body-composition measurements, identified GALNT2 as a candidate shared across breed groups; HCAR1 and ATG10 as candidates specific to the extreme-fat/prolific breed group; and EFNA5 and HIPK2 as candidates specific to the medium-bodied breed group. ROHs identified Soc, Co, and Hung as breeds warranting particular attention in conservation planning due to elevated autozygosity. Because each breed was represented by only six individuals, and because no individual-level phenotypic measurements were available, all findings are reported as exploratory population-genomic signals requiring replication in larger cohorts. Overall, we describe genomic differentiation and candidate selection signatures among local Vietnamese pig breeds and provide a foundation for further genomic studies of these breeds.

Animals↗
PubMed1997

Cryopreservation of pig embryos.

The changing global needs for food and animal products require the development of breeding strategies for maximizing genetic improvement while maintaining genetic diversity. Genetic diversity can be conserved by using separate breeding herds; however, they may be expensive to maintain and inbreeding becomes a major concern. Alternative methods are needed to preserve valuable genetic resources in a reasonable and economic manner. Embryo cryopreservation allows indefinite storage in vitro at subambient temperatures where metabolism and other cellular functions are greatly reduced or cease, and upon recovery from storage, normal developmental competence can be resumed. Storage and transportation require little maintenance and there is no expense in animal care and little concern about disease transmission. Although there are methods for routine cryopreservation of germplasm and embryos of most livestock species, development of this technology in the pig industry is far behind and has abated improvements in genetic potential. Pig embryos are very sensitive to hypothermic conditions, and this limits their ability to withstand many conventional methods of preservation. Much research has focused on the high lipid content of pig embryos, and its role in hypothermic sensitivity and cryosurvival. Many studies have reported the conventional freezing of pig embryos, and vitrification has shown promise of eluding the difficulties associated with cooling sensitivity and ice crystallization. Recent research suggests that the embryonic cytoskeleton is susceptible to damage during cryopreservation, and this cellular disruption may be averted by using cytoskeletal stabilizers before preservation. Embryos cryopreserved by conventional freezing and vitrification under the influence of cytoskeletal stabilization have resulted in pregnancies or live offspring from recipient females after surgical transfer. Although cryopreservation technology is less advanced in pigs than in other livestock species, promising research shows evidence that researchers are close to achieving a methodology for preserving pig embryos.

Animals↗