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J F Taylor

Publications and source records attributed to J F Taylor.

At least 55 records · Page 3Linked to original sources
PubMed1999

Physical assignment of microsatellite- containing BACs to bovine chromosomes.

Here we report the physical assignment of 40 microsatellite markers by fluorescence in situ hybridization to 13 different bovine chromosomes. This information will be valuable in providing physically anchored landmarks for the construction of contigs throughout the bovine genome. It also is useful for the purpose of integrating the linkage maps of these chromosomes to their physical maps and determining the physical coverage of these linkage groups.

Animals↗
PubMed1999

Autosomal trisomy 20 (61,XX,+20) in a malformed bovine fetus.

A 240-day-gestation female bovine fetus with severe anasarca, palatoschisis, cheiloschisis, mild cranioschisis, and a flattened facies was collected at a slaughterhouse, and a fibroblast line was established from the fetal skin. Chromosome preparations were Q-banded, and chromosome counts were taken that indicated the presence of 61 chromosomes in cells of the fetus (the normal diploid number for domestic cattle is 60). Q-band karyotypes were constructed, and Q-band analysis revealed the presence of three copies of chromosome 20. Trisomy 20 (61,XX,+20) was confirmed through the use of two-color fluorescence in situ hybridization of bovine bacterial artificial chromosome clones that were specific to chromosome 20 and the X chromosome.

Animals↗
PubMed1999

Beef customer satisfaction: cooking method and degree of doneness effects on the top loin steak.

The objective of this research was to evaluate the consumer-controlled factors of cooking method and degree of doneness on Top Choice, Low Choice, High Select, and Low Select top loin steaks. The in-home product test was conducted in Chicago, Houston, Philadelphia, and San Francisco. Consumers (n = 2,212) evaluated each top loin steak for overall like (OLIKE), tenderness (TEND), juiciness (JUIC), flavor desirability (DFLAV), and flavor intensity (IFLAV) using 23-point hedonic scales. Respondents in San Francisco and Philadelphia cooked their top loin steaks to lower degrees of doneness than those in Chicago and Houston. Outdoor grilling was the most common method of cookery for top loin steaks in all cities. Consumers had the highest preference for Top Choice steaks (P < .05) and the lowest preference for Low Select steaks (P < .05). Consumer OLIKE scores were the highest (P < .05) for steaks cooked to a medium rare or lesser degree of doneness. Consumers preferred (P < .05) medium and well done or more degrees of doneness over medium well. The interaction of city x cooking method was significant for all steak palatability attributes. The differences in consumer preparation techniques among cities present challenges for the beef industry to develop market-specific promotional campaigns.

Animals↗
PubMed1999

Beef customer satisfaction: cooking method and degree of doneness effects on the top sirloin steak.

The objective of this research was to evaluate the consumer-controlled factors of cooking method and degree of doneness on Top Choice, Low Choice, High Select, and Low Select top sirloin steaks. The in-home product test was conducted in Chicago, Houston, Philadelphia, and San Francisco. Consumers (n = 2,212) evaluated each top sirloin steak for overall like (OLIKE), tenderness (TEND), juiciness (JUIC), flavor desirability (DFLAV), and flavor intensity (IFLAV) using 23-point hedonic scales. Top sirloin steaks, regardless of city, were consistently cooked to well done or higher degrees of doneness. Dry-heat methods such as outdoor grilling, broiling, and indoor grilling were the most frequent cooking methods used. Four significant interactions existed for OLIKE: USDA quality grade x cooking method (P = .02), city x cooking method (P = .0001), city x degree of doneness (P = .01), and cooking method x degree of doneness (P = .009). Greater differences were found between cooking methods within USDA quality grade than between USDA quality grades within cooking method. Consumers in Houston rated steaks cooked by outdoor grilling higher than those from the other cities, and steaks cooked by indoor grilling were rated the highest among all cooking methods by consumers in Chicago. In Chicago, steaks cooked to more advanced degrees of doneness tended to receive higher ratings, but few differences between degrees of doneness in the other three cities were detected. For outdoor grilling, broiling, and pan-frying, the trend was for OLIKE ratings to decline as degree of doneness increased. The lowest customer satisfaction ratings tended to be given to top sirloin steaks cooked to more advanced degrees of doneness, and consumers most frequently cooked steaks to at least the well done stage. Consumer information programs or the development of postmortem techniques that would ensure acceptable palatability of top sirloin steaks may need to be developed.

Animals↗
PubMed1999

Beef customer satisfaction: cooking method and degree of doneness effects on the top round steak.

The objective of this research was to evaluate the consumer-controlled factors of cooking method and degree of doneness on Top Choice, Low Choice, High Select, and Low Select top round steaks. The in-home product test was conducted in Chicago, Houston, Philadelphia, and San Francisco. Consumers (n = 2,212) evaluated each top round steak for overall like (OLIKE), tenderness (TEND), juiciness (JUIC), flavor desirability (DFLAV), and flavor intensity (IFLAV) using 23-point hedonic scales. Stir-frying, braising, and simmering and stewing consistently produced higher consumer attribute ratings. There were clear OLIKE rating differences (P = .0001) for top round steaks among the four cities. The highest ratings were given by consumers in Houston, and the lowest ratings were given by consumers in Philadelphia (P < .05). There were two interactions for OLIKE: USDA quality grade x degree of doneness (P = .002) and degree of doneness x cooking method (P = .02). Higher ratings generally were given to steaks cooked to medium rare or less or to very well degrees of doneness. Stir-frying, braising, and simmering and stewing were preferred at lower degrees of doneness. Customer satisfaction with the top round steak is very dependent on how it is cooked and by whom it is consumed.

Animals↗
PubMed1998

Alström syndrome. Report of 22 cases and literature review.

OBJECTIVE: The authors report 22 cases of Alström syndrome (AS), which is the largest series to date. Only 37 cases have been reported in the world literature since 1959. The authors review the clinical features and compare these with the overlapping condition of Bardet-Biedl syndrome. Their aim is to clarify the AS phenotype and to increase awareness of the early features. DESIGN: A retrospective case series. PARTICIPANTS: All patients (22) with a diagnosis of AS admitted to the authors' hospital in the past 10 years were included in this review. INTERVENTION: This is principally a review of ocular features, but other features are recorded and discussed. MAIN OUTCOME MEASURES: Features noted included age at onset of visual symptoms, presence of photophobia, visual acuity, and electroretinogram findings. Nonocular features recorded included cardiac status, weight and height, hearing, and presence of diabetes mellitus. RESULTS: Cardiomyopathy presenting in infancy has only been recognized recently to be a feature of AS. Of the authors' cases, 18 of 22 had infantile cardiomyopathy. In the authors' tertiary referral institution, there is an ascertainment bias toward younger patients and especially those with pathology that is other than ocular pathology. In addition, AS is difficult to recognize in childhood without the development of infantile cardiomyopathy. Alström syndrome often is not recognized until diabetes mellitus develops in the second or third decade. Initially, a diagnosis of cone-rod dystrophy, achromatopsia, Leber's congenital amaurosis, or Bardet-Biedl syndrome may be made. In AS, there is a severe infantile retinal dystrophy. The electroretinogram is absent or attenuated with better preserved rod than cone function. The retinal dystrophy is progressive with the patient's visual acuity of 6/60 or less by 10 years of age and no light perception by 20 years of age. CONCLUSIONS: A diagnosis of AS should be considered in infantile cone and rod retinal dystrophy, particularly if the weight is above the 90th percentile (16 of 18 cases) or if there is an infantile cardiomyopathy (18 of 22 cases).

Abnormalities, Multiple↗
PubMed1998

A karyotypic analysis of nilgai, Boselaphus tragocamelus (Artiodactyla: Bovidae).

A combination of chromosomal banding and fluorescence in situ hybridization (FISH) was used to characterize the karyotype of Boselaphus tragocamelus (nilgai) relative to the domestic cattle standard karyotype. G-, Q- and C-band karyotypes of nilgai are presented, and the chromosomal complement of nilgai is determined to be 2n=46 (female FN=60, male FN=59; NAA=56), consistent with previous reports for the species. Comparisons with cattle identified extensive monobrachial homologies with some noteworthy exceptions. Chromosome 25 is centrically fused to 24, and chromosome 16 is acrocentric. Both appear to have additional pericentromeric material not seen in the equivalent cattle acrocentrics. This pericentromeric chromatin may be the result of de novo additions or translocation of pericentromeric material from chromosome 6, which is shown to be centrically fused to 13 but is only about two-thirds the length of cattle 6. Comparisons with cattle demonstrated that nilgai chromosome 17 has undergone a paracentric inversion and that chromosome 20 has two blocks of interstitial constitutive heterochromatin. The identities of both chromosomes were confirmed by chromosomal FISH. Furthermore, chromosomal banding and FISH were used to determine that autosome 14 has been fused to the ancestral X and Y of nilgai to form compound neo-X and -Y chromosomes. Additional FISH analyses were conducted to confirm other proposed chromosome homologies and to identify nucleolar organizing regions within the nilgai complement.

Animals↗
PubMed1998

Physical assignment of six type I anchor loci to bovine chromosome 19 by fluorescence in situ hybridization.

A bovine bacterial artificial chromosome (BAC) library was screened for the presence of eight type I anchor loci previously used within hybrid somatic cells and an interspecies hybrid backcross to construct a genome map of bovine chromosome 19 (BTA19). Six out of eight loci were identified in the BAC library (NF1, CRYB1, CHRNB1, TP53, GH1 and P4HB). The BACs were then used in single-colour fluorescence in situ hybridization (FISH) to assign these genes to BTA19 band locations. Gene order was determined by single-colour FISH, and was confirmed by dual-colour FISH to mitotic and meiotic chromosomes. The order, centromere-NF1-CRYB1-CHRNB1-TP53-GH1-P4HB, was in agreement with the order determined by linkage analyses. In addition, the order of CHRNB1 and TP53, previously unresolved by linkage analyses, was established. These data provide high-resolution cytogenetic anchorage of the BTA19 genome map from chromosome bands 14-22.

Animals↗
PubMed1998

Candidate gene analysis of GH1 for effects on growth and carcass composition of cattle.

We present an approach to evaluate the support for candidate genes as quantitative trait loci (QTLs) within the context of genome-wide map-based cloning strategies. To establish candidacy, a bacterial artificial chromosome (BAC) clone containing a putative candidate gene is physically assigned to an anchored linkage map to localise the gene relative to an identified QTL effect. Microsatellite loci derived from BAC clones containing an established candidate gene are integrated into the linkage map facilitating the evaluation by interval analysis of the statistical support for QTL identity. Permutation analysis is employed to determine experiment-wise statistical support. The approach is illustrated for the growth hormone 1 (GH1) gene and growth and carcass phenotypes in cattle. Polymerase chain reaction (PCR) primers which amplify a 441 bp fragment of GH1 were used to systematically screen a bovine BAC library comprising 60,000 clones and with a 95% probability of containing a single copy sequence. The presence of GH1 in BAC-110R2C3 was confirmed by sequence analysis of the PCR product from this clone and by the physical assignment of BAC110R2C3 to bovine chromosome 19 (BTA19) band 22 by fluorescence in situ hybridisation (FISH). Microsatellite KHGH1 was isolated from BAC110R2C3 and scored in 529 reciprocal backcross and F2 fullsib progeny from 41 resource families derived from Angus (Bos taurus) and Brahman (Bos indicus). The microsatellite KHGH1 was incorporated into a framework genetic map of BTA19 comprising 12 microsatellite loci, the erythrocyte antigen T and a GH1-TaqI restriction fragment length polymorphism (RFLP). Interval analysis localised effects of taurus vs. indicus alleles on subcutaneous fat and the percentage of either extractable fat from the Iongissimus dorsi muscle to the region of BTA19 harbouring GH1.

Animals↗
PubMed1998

Molecular systematics and paleobiogeography of the South American sigmodontine rodents.

The murid rodent subfamily Sigmodontinae contains 79 genera which are distributed throughout the New World. The time of arrival of the first sigmodontines in South America and the estimated divergence time(s) of the different lineages of South American sigmodontines have been controversial due to the lack of a good fossil record and the immense number of extant species. The "early-arrival hypothesis" states that the sigmodontines must have arrived in South America no later than the early Miocene, at least 20 MYA, in order to account for their vast present-day diversity, whereas the "late-arrival hypothesis" includes the sigmodontines as part of the Plio-Pleistocene Great American Interchange, which occurred approximately 3.5 MYA. The phylogenetic relationships among 33 of these genera were reconstructed using mitochondrial DNA (mtDNA) sequence data from the ND3, ND4L, arginine tRNA, and ND4 genes, which we show to be evolving at the same rate. A molecular clock was calibrated for these genes using published fossil dates, and the genetic distances were estimated from the DNA sequences in this study. The molecular clock was used to estimate the dates of the South American sigmodontine origin and the main sigmodontine radiation in order to evaluate the "early-" and "late-arrival" scenarios. We estimate the time of the sigmodontine invasion of South America as between approximately 5 and 9 MYA, supporting neither of the scenarios but suggesting two possible models in which the invading lineage was either (1) ancestral to the oryzomyines, akodonts, and phyllotines or (2) ancestral to the akodonts and phyllotines and accompanied by the oryzomyines. The sigmodontine invasion of South America provides an example of the advantage afforded to a lineage by the fortuitous invasion of a previously unexploited habitat, in this case an entire continent.

Animals↗
PubMed1998

Report of the first workshop on the genetic map of bovine chromosome 1.

A report of the first workshop on the genetic map of bovine chromosome 1 (BTA1) is presented. Five laboratories contributed 31,962 informative meioses from 70 loci. Thirty-two loci which had been typed by at least two laboratories were used to construct a framework genetic map with a likelihood ratio support of at least 1000:1 for locus order. The resulting sex-averaged framework map contained 26 loci and spanned 163.6 CM. The lengths of the female and male maps were 159.5 CM and 165.3 CM, respectively, and there was evidence for an expansion in the telomeric one-third of the male map. Of the four cases where order for closely linked loci differed among the maps produced for each of the contributing laboratories, a consensus order was obtained for three in the framework map. The average genetic distance between framework loci on the sex-averaged map was 6.3 CM.

Animals↗
PubMed1998

Beef customer satisfaction: role of cut, USDA quality grade, and city on in-home consumer ratings.

An in-home beef study evaluated consumer ratings from moderate-to-heavy beef users as influenced by cut (top loin, top sirloin, and top round steaks), USDA quality grade (Top Choice, Low Choice, High Select, and Low Select), and city (Chicago, Houston, Philadelphia, and San Francisco). Consumers (n = 2,212) evaluated each steak for overall like (OLIKE), tenderness (TEND), juiciness (JUIC), flavor desirability (DFLAV), and flavor intensity (IFLAV) using 23-point hedonic scales (23 = like extremely, extremely tender, extremely juicy, like extremely, and an extreme amount of flavor; 1 = dislike extremely, not at all tender, not at all juicy, dislike extremely, and no flavor at all). A USDA grade x cut interaction existed for OLIKE (P < .05). Consumers rated top loin steaks highest (P < .05) in OLIKE and ranked Top Choice highest of all steaks (P < .05). Within the top loin, consumers were not (P > .05) able to distinguish OLIKE differences between Low Choice and High Select or between High Select and Low Select. For OLIKE, top sirloin was rated intermediate (P < .05) of the three cuts, and consumers were not able to detect (P > .05) USDA quality grade differences. For OLIKE, top round was the lowest-rated (P < .05) cut. However, consumers preferred (OLIKE, P < .05) Top Choice to the other USDA grades offered. Grade and city interacted to affect TEND, JUIC, DFLAV, and IFLAV. The cut x city interaction was significant for all palatability attributes. Cut and city affected customer satisfaction more than USDA quality grade. Tenderness and flavor were important and equal contributors to OLIKE, r = .85 and r = .86, respectively.

Adult↗
PubMed1998

Blood groups and milk and type traits in dairy cattle: after forty years of research.

This study addresses the utility of 11 blood groups as selection aids in Holstein breeding schemes and considers issues inherent to the approach of resolving quantitative variation into components that are due to quantitative trait loci. The data consisted of predicted transmitting abilities of 22,614 bulls, first lactation information on 1,924,171 cows, and type scores on 447,800 cows. Linear models were fitted under male half-sib designs, female half-sib designs, and granddaughter designs as well as under the assumption of direct effects of the markers. The evolution of allele frequencies through time was determined, and previous research results were synthesized according to criteria of consistency of biological significance. The inconsistency of results across studies and analytical designs alludes to the importance of the intrinsic nonadditivity of genetic and biological phenomena to quantitative trait locus detection and marker-assisted selection. In our analyses, three associations met the criteria of consistency--a C blood group effect on rump angle, an L effect on milk yield and composition traits, and an S effect on milk fat yield. The M locus appears to be directly associated with effects on milk and protein yields. An enhanced understanding of the biochemical and physiological bases of quantitative genetics should be a long-term objective of this type of genetic analysis.

Animals↗
PubMed1998

Trait-based analysis in dairy cattle using blood group polymorphisms.

The potential of trait-based analysis to detect quantitative trait loci was investigated using blood group polymorphisms as the marker systems and milk and type traits in Holstein cattle as the quantitative traits. Within large half-sib families, animals were ranked on their predicted transmitted abilities or phenotypes, and blood group allele frequencies were compared between the upper and lower 5% tails of the distributions. Genotype frequencies within large families were also examined for evidence of selection. All of the major effects that had previously been detected using linear model analyses were identified by the trait-based analyses of a C blood group effect on rump angle, an L effect on milk yield and composition traits, an S effect on milk fat yield, and a direct effect of the M locus on milk and protein yields. These results provide additional support for the biological validity of these associations and also demonstrate the utility of trait-based analysis for the detection of quantitative trait loci within existing dairy breeding programs. However, just as in the linear model analyses, an analytical strategy should be utilized that allows the identification of the effects that are consistent across environments and genetic backgrounds.

Alleles↗
PubMed1998

Comparative mapping of bovine chromosome 13 by fluorescence in situ hybridization.

We present chromosomal fluorescence in situ hybridization (FISH) results that both extend the HSA20/BTA13 comparative map as well as cytogenetically anchor two microsatellite markers. A bovine bacterial artificial chromosome (BAC) library was screened for conserved genes (type 1 loci) previously assigned to HSA10 or HSA20 and BTA13, and for microsatellites selected from two published BTA13 linkage maps. Clones from six out of nine comparative loci and both microsatellites were found represented in the BAC library. These BAC clones were used as probes in single colour FISH to determine the chromosome band position of each locus. As predicted by the human/bovine comparative map, all type 1 loci mapped to BTA13. Because single colour FISH analysis revealed that the loci were clustered within the distal half of BTA13, dual colour FISH was used to confirm the locus order. Established order was centromere-PRNP-(SOD1L/AVP/OXT)-(BL42/GNAS1)- HCK-CSSM30. The findings confirm the presence of a conserved HSA20 homologous synteny group on BTA13 distal of a HSA10 homologous segment.

Animals↗
PubMed1997

Comparative linkage mapping of human chromosome 13 and bovine chromosome 12.

A comparative linkage map of human chromosome 13 and bovine chromosome 12 was constructed using eight polymorphic microsatellite markers associated with six specific genes. Linkage of these was also examined relative to five previously mapped anonymous microsatellite markers. Seven gene-linked markers were developed from bovine large-insert genomic clones containing one of five genes of interest (serotonin receptor subtype 2, fms-related tyrosine kinase, coagulation factor 10, retinoblastoma susceptibility gene, collagen type IV alpha 1), and one additional marker was developed from a microsatellite resident within an intron of the bovine dopachrome tautomerase gene. Four of these loci were previously assigned to bovine chromosome 12 by analysis of a somatic cell hybrid panel. This study provides linkage information for examining gene order in this conserved synteny group. The comparative linkage mapping results indicate that the q arm of human chromosome 13 is almost entirely conserved in bovine chromosome 12. One intrachromosomal rearrangement was detected in this linkage group relative to human, and this rearrangement was confirmed by fluorescence in situ hybridization results.

Animals↗