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PubMed1988

Superficial stromal keratitis in the dog.

Superficial stromal keratitis or pannus is a syndrome of corneal, conjunctival and third eyelid inflammation. Superficial stromal keratitis mainly presents as a subepithelial corneal infiltration of vascular connective tissue, and usually arises from the lateral (temporal) limbal area. In some dogs perilimbal hyperaemia and third eyelid blepharitis can be present without corneal involvement. The most commonly affected breed of dog is the German Shepherd. Most cases of superficial stromal keratitis can be controlled with topical corticosteroids, and only rarely is cryosurgery or superficial keratectomy required to remove excessive pigment and or granulation tissue. The precise aetiology of SSK is unknown, but is likely to be multifactorial, with sunlight being a significant factor. Corneal lipidosis and keratoconjunctivitis sicca can occur secondary to superficial stromal keratitis.

Adrenal Cortex Hormones↗
PubMed2003

Comparison of different methods to assess the composition of pig bellies in progeny testing.

The objective of the study was to validate methods that assess the belly composition of stationary tested progenies of Piétrain boars. In German performance test stations, there are currently three methods of determining belly compositon in use: 1) a regression equation that contains different carcass characteristics, such as fat thickness and muscle area; 2) planimetric analysis of video or digital images acquired at the cut between the 13th and 14th ribs; and 3) estimation of the belly composition using ultrasound data from a three-dimensional ultrasound image produced an online carcass-grading system. Validation of these techniques was performed on 400 carcasses of stationary-tested Piétrain and Piétrain-sired crossbred pigs, which were slaughtered at a mean carcass weight of 85 and 97 kg. Magnetic resonance imaging (MRI) served as a reference to determine the lean content of the bellies. The correlation to MRI lean content ranged from 0.71 to 0.81, and corresponding correlation values were 0.62 to 0.64 for the digital imaging technique, and 0.53 to 0.59 for the AutoFOM online carcass-grading system. An increase in precision was achieved when information from digital imaging and linear carcass measures were included in the regression equation. Accuracy of the AutoFOM system does not seem to be sufficient to assess the belly composition for the special breeds in performance testing. However, extracting and combining 127 AutoFOM-base recordings into modified equations using partial least squares techniques yielded an improvement in the prediction accuracy for all tested breed and/or weight groups.

Adipose Tissue↗
PubMed1981

Determination of plasma fibrinogen concentration in the horse.

The microhematocrit heat-precipitation methods of Millar et al (1971) and Schalm et al (1975) were compared with the reference clottable protein method of Ratnoff and Menzie (1951) in the measurement of plasma fibrinogen concentration in horses. The millar et al method was more precise and accurate and showed better positive correlation with the reference method than did the Schalm et al method. There was no significant difference in the plasma fibrinogen concentration between healthy Thoroughbreds and healthy horses of other breeds. Horses with bacterial pneumonia and abscesses had significantly greater plasma fibrinogen values than did those with colic, fractures, and nonsuppurative wounds. The Millar et al method was recommended as a simple, relatively accurate procedure for the determination of plasma fibrinogen that might be used as an additional diagnostic and prognostic indicator in the laboratory investigation of diseases in the horse.

Animals↗
PubMed1998

Electroretinographic evaluation of Papillons with and without hereditary retinal degeneration.

OBJECTIVE: To evaluate the function of the outer retina in Papillons with and without hereditary retinal degeneration. ANIMALS: 45 Papillons, median age 1.7 (range, 0.8 to 5.1) years. PROCEDURE: Complete physical and ophthalmic examinations were done prior to performing electroretinography under general anesthesia. Full-field electroretinograms (ERG) were recorded, using a special-purpose computer system. Eleven specific ERG responses were recorded, graphed, and evaluated, using age-matched Papillons. RESULTS: Severely decreased retinal function was detected in 8 Papillons. The youngest affected dog was 1.2 years old. In affected dogs, amplitudes of responses mainly originating from the rod system were severely decreased, compared with those originating from the cone system. CONCLUSIONS: Papillons represent another breed of dog affected by a hereditary photoreceptor degeneration that can be detected at an early age by using ERG. A reliable age for diagnosis using ERG is considered to be 1.5 years. CLINICAL RELEVANCE: Through and precise ERG procedures and protocols are needed to reliably obtain an early diagnosis of progressive retinal atrophy.

Aging↗
PubMed2002

Genotyping Brahman cattle for generalised glycogenosis.

OBJECTIVE: To develop procedures for genotyping Brahman cattle for loss-of-function alleles within the acidic alpha-glucosidase gene and to assess the risk of generalised glycogenosis in Australian Brahman cattle. DESIGN: PCR assays for three loss-of-function alleles were designed to exploit internal restriction sites within acidic alpha-glucosidase amplicons that are independent of allelic variants at the mutant sites. RESULTS: Genotyping 8529 clinically normal Brahmans between August 1996 and August 2001 revealed 16.4% were heterozygous for the more common of the two mutations (1057deltaTA, often referred to as the 'E7' mutation) that cause generalised glycogenosis in this breed. The less common 1783T mutation (often referred to as the 'E13' mutation) was restricted to descendants of one imported bull, and was not detected in 600 randomly selected Brahmans. Prior to definition of these two disease-causing mutations, 640 (18%), and 14 (0.4%), of 3559 clinically normal Brahmans analysed between January 1994 and December 1996, were heterozygous, and homozygous, respectively, for a silent polymorphism (2223G-->A) that is associated with generalised glycogenosis. In addition to the 1057deltaTA and 1783T mutations, approximately 15% of Brahmans were found to be heterozygous for a single base substitution in exon 9 (1351T, commonly referred to as the 'E9' mutation) that significantly reduces acidic alpha-glucosidase activity, but has not been associated with clinical disease. These three loss-of-function alleles were found in Brahmans imported, or selected for import, from the USA. CONCLUSION: The PCR procedures reported here represent a significant improvement in reliability and accuracy over previous published methods. Utilisation of these PCR/restriction enzyme based assays will facilitate precise selection against the 1057deltaTA and 1783T alleles, and consequently reduce the incidence of generalised glycogenosis in registered and commercial Brahman herds.

Animals↗
PubMed1982

Mineral concentrations in hair as indicators of mineral status: a review.

Mineral content of hair is affected by season, breed, hair color within and between breeds, sire, age and body location. Seasonal effects may be due to stage of growth of hair and to changes caused by perspiration, surface contamination and diet. Breed and sire effects on mineral content of hair complicate prediction of nutritional status based on hair analyses because, in many commercial cattle, neither breed nor sire is known. Hair from young animals may be lower in Zn, Mn and Fe, but is higher in Na, Ca, Cu and K than that from older animals. Pigmented hair apparently is higher in Ca, Mg, K and NA than white hair, but trace mineral concentrations are similar in hair of different colors. The effect of body location on mineral content of hair may be due to differences in surface contamination, differences in hair growth cycles and differences in texture of the hair. Concentrations of Ca, P and Cu in hair are not affected by dietary intake of these minerals. Zn and Se contents of hair may reflect dietary intake. Information on other required minerals in lacking. Pb, As and, possibly, Cd levels in hair may be related to dietary or environmental exposure. Because of the many factors that cause variation in mineral content of hair, hair analyses are not likely to be precise indicators of the mineral status of animals. Hair analyses may help to detect severe deficiencies of some required minerals or exposure to some heavy metals. However, if hair analyses are to be conducted, care must be taken to compare values from test animals with those from animals of similar breed, sex, season, sire and color. In addition, new hair growth should be analyzed, environmental contamination should be minimized and the hair samples should be cleaned before analyses.

Age Factors↗
PubMed2006

The prediction of parturition date in canine pregnancy.

In bitches, the length of gestation is highly variable when measured from the day of mating, thus prediction of parturition may be greatly inaccurate when determined from this point. The ability to precisely predict the duration of pregnancy is of practical importance for managing parturition or planning caesarean section and this review analyses the methods that can be used to accurately forecast the day of parturition. At the time of breeding, determination of the luteinizing hormone surge and the initial rise in progesterone provide reliable information on gestational length of the bitch, but when pregnancy is ascertained, ultrasonography is the most useful tool to predict the delivery day. In fact, by ultrasonographic measurements of the extra-foetal and foetal structures an accurate prediction can be made both in early and late pregnancy.

Animals↗
PubMed2006

Genetic evaluation of mastitis in dairy cattle using linear models, threshold models, and survival analysis: a simulation study.

The objective was to study, by simulation, whether survival analysis results in a more precise genetic evaluation for mastitis in dairy cattle than cross-sectional linear models and threshold models by using observation periods for mastitis of 2 lengths (the first 150 d of lactation, and the full lactation, respectively). True breeding values for mastitis liability on the underlying scale were simulated for daughters of 400 sires (average daughter group size, 60 or 150), and the possible event of a mastitis case within lactation for each cow was created. For the linear models and the threshold models, mastitis was defined as a binary trait within either the first 150 d of lactation or the full lactation. For the survival analysis, mastitis was defined as the number of days from calving to either the first case of mastitis (uncensored record) or to the day of censoring (i.e., day of culling, lactation d 150 or day of next calving; censored record). Cows could be culled early in lactation (within 10 d after calving) for calving-related reasons or later on because of infertility. The correlation between sire true breeding values for mastitis liability and sire predicted breeding values was greater when using the full lactation data (0.76) than when using data from the first 150 d (0.70) with an average of 150 daughters per sire. The corresponding results were 0.60 and 0.53, respectively, with an average of 60 daughters per sire. Under these simulated conditions, the method used had no effect on accuracy. The higher accuracy of sire breeding values can be translated into a greater genetic gain, unless counteracted by a longer generation interval.

Animals↗
PubMed2026

Integrated Genomics and Transcriptomics Reveal Stable Resistance Loci and Candidate Genes for Powdery Mildew in Wheat.

Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), poses a substantial threat to global wheat production. Enhancing resistance through molecular breeding necessitates a comprehensive understanding of its genetic and molecular underpinnings. This study leveraged a 2-year phenotypic evaluation of 283 diverse wheat accessions combined with genome-wide association studies (GWAS) to pinpoint stable quantitative trait loci for powdery mildew resistance. We identified 52 robust resistance loci across the wheat genome, including seven novel loci consistently detected across four environments. Comparative transcriptome profiling of resistant and susceptible wheat lines revealed 95 differentially expressed genes, predominantly enriched in defense response, signal transduction, and transcription regulation pathways. By integrating the GWAS and transcriptomic data, we precisely identified three compelling candidate genes (TaPIP5K, TaPKG, and TaORR6) on chromosome 2A, which are implicated in cell wall reinforcement, jasmonic acid signaling, and reactive oxygen species scavenging, respectively. Further validation using expression analysis corroborated their pivotal roles in resistance. Our findings provide a rich repository of validated genetic markers, promising candidate genes, and superior resistant germplasms, offering critical resources to accelerate targeted molecular breeding efforts for durable powdery mildew resistance in wheat.

Blumeria graminis f. sp. tritici↗
PubMedDate not supplied

Appearance of eosinophilic granule cells as pathological changes in the uteri of two aged virgin Donryu rats.

The morphological features of cells containing eosinophilic granules (EG cells) present as pathological changes in the uteri of 2 aged virgin Donryu rats were described and compared with granulated metrial gland (GMG) cells of a pregnant rat. Microscopically, EG cells distributed diffusely from the mesometrial triangle to the subendometrium with partly focal accumulation in Case 1 and infiltrated diffusely from the endometrium to the serosa without any clumping in Case 2. They were large cells with eosinophilic and hyaline intracytoplasmic granules, positive for the periodic acid-Schiff reaction. Both EG and GMG cells reacted positively to concanavalin A, wheat germ agglutinin, and phytohemagglutinin on lectin histochemical investigation, although common results were not always obtained for immunohistochemistry. These results show that EG cells are morphologically similar to GMG cells, suggesting a possibility that EG cells are GMG cells. EG cells were without neoplastic properties or pronounced cell-proliferative activity. In Case 1, histological changes of the ovaries and vagina were indicative of a pseudopregnant status. In Case 2, the rat had been maintained under abnormal hormonal conditions, and no evidence of any pseudopregnant-like status was found. These results suggest, thus, that the appearance of EG cells is evidence of a reactive pathological condition in the uteri of aged virgin rats, although the precise pathogenesis and biological significance of EG cells remain to be determined.

Aging↗
PubMed1996

Marker-assisted introgression in backcross breeding programs.

The efficiency of marker-assisted introgression in backcross populations derived from inbred lines was investigated by simulation. Background genotypes were simulated assuming that a genetic model of many genes of small effects in coupling phase explains the observed breed difference and variance in backcross populations. Markers were efficient in introgression backcross programs for simultaneously introgressing an allele and selecting for the desired genomic background. Using a marker spacing of 10-20 cM gave an advantage of one to two backcross generations selection relative to random or phenotypic selection. When the position of the gene to be introgressed is uncertain, for example because its position was estimated from a trait gene mapping experiment, a chromosome segment should be introgressed that is likely to include the allele of interest. Even for relatively precisely mapped quantitative trait loci, flanking markers or marker haplotypes should cover approximately 10-20 cM around the estimated position of the gene, to ensure that the allele frequency does not decline in later backcross generations.

Alleles↗
PubMed2006

Efficiency of playback for assessing the occurrence of five bird species in Brazilian Atlantic Forest fragments.

Playback of bird songs is a useful technique for species detection; however, this method is usually not standardized. We tested playback efficiency for five Atlantic Forest birds (White-browed Warbler Basileuterus leucoblepharus, Giant Antshrike Batara cinerea, Swallow-tailed Manakin Chiroxiphia caudata, Whiteshouldered Fire-eye Pyriglena leucoptera and Surucua Trogon Trogon surrucura) for different time of the day, season of the year and species abundance at the Morro Grande Forest Reserve (South-eastern Brazil) and at thirteen forest fragments in a nearby landscape. Vocalizations were broadcasted monthly at sunrise, noon and sunset, during one year. For B. leucoblepharus, C. caudata and T. surrucura, sunrise and noon were more efficient than sunset. Batara cinerea presented higher efficiency from July to October. Playback expanded the favourable period for avifaunal surveys in tropical forest, usually restricted to early morning in the breeding season. The playback was efficient in detecting the presence of all species when the abundance was not too low. But only B. leucoblepharus and T. surrucura showed abundance values significantly related to this efficiency. The present study provided a precise indication of the best daily and seasonal periods and a confidence interval to maximize the efficiency of playback to detect the occurrence of these forest species.

Animals↗
PubMed1990

Genotyping of bovine kappa-casein loci following DNA sequence amplification.

Caseins are a family of milk proteins that exist in several molecular forms (alpha s1, alpha s2, beta and kappa) with variant alleles of each. Kappa-caseins (kappa-CN) exist as A or B variants and are of particular importance to the quality of the milk. We report a rapid non-radioactive method for differentiating bovine k-CN alleles. Unlike direct milk protein analysis, this method can be utilized for genotyping sperm, or animals of either sex at an early age. A 350bp fragment of the bovine kappa-CN gene was amplified by the polymerase chain reaction (PCR) technique. The amplified product digested with HinfI endonuclease generated restriction fragment length polymorphisms (RFLP's) that allowed precise identification of kappa-CN AA, AB or BB genotypes. Hybridization with allele specific oligo-probes confirmed the RFLP identification of genotypes. The accurate and early identification of milk protein genotypes can have a direct impact on dairy cattle breeding strategies.

Alleles↗
PubMed2000

Estrus synchronization of lactating dairy cows with GnRH, progesterone, and prostaglandin F2 alpha.

The reproductive performance of synchronized cows was compared with that of nonsynchronized cows. In trial 1, cyclic cows in five seasonal herds were randomly divided into two groups. Cows in one group (n = 515) were treated with a GnRH agonist and an intravaginal progesterone device, followed in 7 d by a PGF2 alpha injection, and the device was removed 1 d after PGF2 alpha. Cows in the other group (n = 512) did not receive any treatment and acted as control. In trial 2, the treatments were similar to those used in trial 1 except that the progesterone device was removed at the time of PGF2 alpha injection (synchronized: n = 516; control: n = 512). The estrus synchronization rate was 92.8% in trial 1 and 92.2% in trial 2. Conception rate to first artificial insemination (AI) was lower for synchronized cows than for control cows in trial 1 (56.5 vs. 62.7%), but similar in trial 2 (64.6 vs. 63.3%). Across both trials, the pregnancy rate during the AI breeding period was greater for the synchronized cows (85.6%) than for the control cows (81.2%). The synchronization treatment reduced the interval from start of the breeding season to conception for cows conceiving by AI (8.9 vs. 14.8 d) or by AI or natural mating (14.1 vs. 21.6 d). The synchronization protocol used in trial 2 achieved better conception rate than that used in trial 1, but the precision of estrus was less in trial 2 than in trial 1.

Administration, Intravaginal↗
PubMed1999

Biotechnology and world food supply.

Biotechnology, the use of molecular and cellular tools to genetically modify and improve food supply, will play an increasing and important role in the continuing struggle to produce sufficient food for an ever increasing world population. Many of the approaches will supplement and enhance conventional breeding and also address environmental concerns and help to stabilize food production. This review provides a perspective dealing specifically with crops and three areas of biotechnology, namely, genome analysis with molecular markers, cell- and tissue-culture procedures, and the rapid and precise incorporation of genes via transformation. One must remember that biotechnology is still in its infancy, and that approaches will be greatly improved and more efficiently utilized in the future for the betterment of mankind.

Biotechnology↗
PubMed1997

Ancillary tests of bull semen quality.

Seminal quality examinations readily identify animals with low fertility, but rarely can these tests discriminate among males with moderate to high fertility. The new, automated semen analysis systems tend to be helpful in providing more reliable information. Such systems, especially the CASA systems that assess sperm morphology and motility, are innovative and certainly attractive. They may not, however, be cost effective. Similarly, although the combination of fluorescent staining and flow cytometry offers a very rapid and precise means of assessing the functional status of sperm organelles, it tends to be relatively expensive as a clinical tool. Such automated sperm quality assessments will likely become routine analyses at the larger semen-processing organizations. However, the true success of a breeding program can only be assessed by the number of live offspring. Thus, determination of true fertility, because of the complexity of the processes that unite the gametes, will continue to require more than a detailed examination of seminal cytology, no matter how sophisticated our methods become.

Animals↗
PubMed1995

Clonal diffusion of EPEC-like Escherichia coli from rabbits as detected by ribotyping and random amplified polymorphic DNA assays.

The genetic diversity and clonal relationships among 77 Escherichia coli strains isolated in France from diarrhoeic rabbits and that belonged to seven O serogroups including the predominant O103 serogroup, were estimated by ribotyping and random amplified polymorphic DNA (RAPD) assays. Fifteen ribotypes were defined. Most of the highly pathogenic O103 strains could be assigned to two major groups. Non-pathogenic strains were clearly distinguished. RAPD assays generally matched ribotyping, or gave more precision for subdividing strains from the two main O103 groups. The results on strains isolated from different areas and over a 9-year period showed the relevance of the association of these two methods for the survey of the spread of strains in breeding flocks and illustrated clonal diffusion in rabbit production structures.

Animals↗
PubMed2026

Genomic Insights Into Heterosis: Dominance or Additive × Additive Interaction?

Heterosis was documented in the 18th century, but its biological basis has been debated since. The theoretical framework proposed by Hill, and adapted by Lynch, is based on two central parameters: admixed composition (S), and the heterozygosity (H). Using genomic information, it is now possible to estimate independently the individual realized Si and Hi. In this research, a methodology for estimating the contribution of dominance and additive &#xd7; additive effects to heterosis is proposed. This approach would be especially relevant in cases where there is insufficient phenotypic information available, or an adequate genetic group experimental design, common in humans, wild species and other admixed populations. We also provide theoretical arguments highlighting the enhanced precision of the estimations of heterosis parameters through this method. Furthermore, we exemplify this procedure by analysing data from an experimental F2 pig population, which was initially designed for QTL mapping. Notably, all animals in this population were genotyped (including F1 and parental breeds), but phenotypic information was only available for F2 individuals and included 13 traits related to growth, fat deposition, carcass characteristics and meat quality. Significant additive effects (p&#x2009;<&#x2009;0.05) were detected for longissimus muscle area and carcass temperature, suggesting complementary additive effects for these traits. Significant dominance and additive &#xd7; additive effects were also detected for birth weight and carcass length, respectively (p&#x2009;<&#x2009;0.05), indicating that heterosis for these traits is primarily attributable to dominance and additive &#xd7; additive interactions. These results demonstrate that the proposed methodology can successfully estimate the genetic components underlying heterosis and underscores the utility of this approach in&#xa0;situations where we possess genomic data but limited phenotypic data.

SNP↗