Biomedical subjects

F Minvielle

Publications and source records attributed to F Minvielle.

32 records · Page 2Linked to original sources

PubMed1994

Heterosis in normal versus dwarf laying hens.

The effect of genotype at the sex-linked dwarf locus on heterosis in crosses between a White Leghorn and a brown egg line for body weight, egg production, and related traits was studied. Heterozygous Dw/dw males were used to produce normal and dwarf pullets in each of the pure lines and their reciprocal crosses (eight genotype-line combinations). There were 54 pullets per combination. Line differences were significant for shank length, body weights at 8, 17, and 52 wk, age at first egg, egg number, clutch length, rate of lay, and egg weight. Heterosis was observed for all of these traits. Body weight as a covariate was not important in analyses of egg number, clutch length, and egg weight. The egg production reduction associated with the dw gene in pure lines was smaller in F1 hens. This discovery may be adequate to warrant use of dwarf crossbred hens for egg production.

Animals↗

PubMed1994

Retinal distribution of tyrosine hydroxylase immunoreactive cells in two strains of quails Coturnix coturnix japonica.

We have compared the distribution of tyrosine-hydroxylase immunoreactive (TH-I) somata in the retina of two strains of japanese quails, one normally pigmented and one hypopigmented mutant which develops a glaucoma, three months after their hatching. TH-I cells were observed among amacrine and presumptive interplexiform cells in both strains. They were distributed in areas of decreasing densities from an area centralis, located in the central upper retina to the retinal periphery. We have arbitrarilly grouped them in four classes of different densities: A class with 41 cells/mm2 and more, B class (from 31 to 40 c/mm2), C class (from 21 to 30 c/mm2) and D class (20 c/mm2 and less) and drawn isodensity lines. The comparison of cell mean density in each zone showed no major differences between the strains. Conversely, the comparison of the relative retinal surface occupied by each zone demonstrated a significant variation of C and D zones which appeared to be counterbalanced: the C zone being larger and the D zone smaller in pigmented quails compared with mutant quails. The possible involvement of such a TH-I cell distribution and consequently of the dopaminergic system in the development of glaucoma is discussed.

Animals↗

PubMed1991

Computer simulation model of swine production systems: I. Modeling the growth of young pigs.

Theoretical concepts and relationships were used to develop a deterministic pig growth model. The model predicts, in a continuous form, growth and body composition of boars, barrows, and gilts according to genotype, diet, and management conditions. The model is aggregated at the whole-animal level with three main elements of body composition; total body DNA, total body protein mass (PT), and total body mass of lipids, with PT determining the secondary elements of ash and moisture. The primary factors regulating growth were associated with cellular hyperplasia and hypertrophy in agreement with the basic concepts described by Baldwin and Black (1979). Differential equations representing DNA accretion and protein synthesis and degradation were adapted from Oltjen et al. (1985). Normal pig protein growth was characterized from published data. Body PT was used to reflect several metabolic activities related to animal size and age, as in some prior models. Dietary energy and protein were used in sequence until requirements are satisfied, first for maintenance, then for protein growth, and finally for fat deposition. A comparison between experimental and simulated results illustrates that the model may simulate growth and body composition of young pigs adequately.

Animals↗

PubMed1991

Computer simulation model of swine production systems: II. Modeling body composition and weight of female pigs, fetal development, milk production, and growth of suckling pigs.

Theoretical concepts and relationships used to develop a deterministic computer simulation model of female pigs during their reproductive life are described. The model predicts, in a continuous form, body composition and weight of female pigs, fetal development, sow milk yield, and growth of suckling pigs according to genotype, diet, and management conditions. The model simulates growth of adult female pigs. Dietary nutrients are used first for maintenance and second for fetal growth or milk production. Any surplus is retained in the body. Energy and protein body reserves are mobilized when a nutrient deficit occurs during gestation or lactation. However, the rates of body protein and fat accretion as well as the fat/protein ratio are limited by boundaries, the values of which depend on the nutritional and physiological status of the pig. The model's ability to simulate sow body weight changes and composition, fetal growth, milk production, and suckling pig's growth is illustrated.

Animals↗

PubMed1991

Computer simulation model of swine production systems: III. A dynamic herd simulation model including reproduction.

A dynamic herd simulation model for a swine production unit has been developed. The model is discrete and stochastic and the appropriate random distributions have been defined from the literature or empirically estimated. Theoretical concepts and relationships presented previously are used to simulate growth and the overall life cycle of individual animals. Simulated animals are young pigs (from birth to slaughter age), gilts, and sows. Animal events are farrowing, weaning, mating, end-nursery (transfer from nursery to the growing-finishing facility), and slaughter and are processed individually using a next-event scheduling orientation package. Animals within the herd are culled for different health and reproductive reasons. Genetic parameters, diet composition, and herd management are input variables chosen by the user. The effects of nutrition, genetics, season, and other factors on several reproductive parameters are considered. Model evaluation is performed by studying the output of the model under specified herd situations. The herd model adequately simulates animal flow and dynamics of the herd.

Animal Nutritional Physiological Phenomena↗

PubMed1991

[Diagnostic value of pulsed Doppler in atheromatous renal insufficiency. A study of 32 patients].

RATIONALE: atheromatous stenosis of both renal arteries, or of the artery of a functionally solitary kidney is a frequent cause of renal failure in the elderly. Atheromatous Ischemic Renal Insufficiency (AIRI) can be ameliorated by surgery or angioplasty. However, such procedures can be hazardous in a patient with extensive aortic atheromatous plaques. This justified a study of the validity of Pulsed Doppler (PD), a diagnostic procedure less invasive than renal angiography in AIRI. OBJECTIVES: to evaluate the diagnostic interest of PD in AIRI, using renal angiography as a criterion of adequacy. METHODS: renal arteries PD (Ultramak-4, 3.5 and 5 Mhz probes) followed by renal angiography (Seldinger). "Significant" stenosis = 50% on angiography. "Positive" PD = turbulences and/or acceleration. PATIENTS: 32 patients were investigated for suspected AIRI on the grounds of 1) age greater than 50; 2) atheromatous background and 3) renal insufficiency with no other evident etiology, or rapidly declining GFR in such a patient treated with ACE inhibitors. RESULTS: 16/32 angiographies disclosed significant stenosis of at least 1 renal artery. 56 renal arteries were investigated with both angio. and PD. Prevalence of stenoses was 16/56. PD had 93.7% sensitivity and 55% specificity. Positive predictive value was 45.5% and negative predictive value was 95.7%. Specificity was 80% when PD disclosed acceleration. CONCLUSIONS: negative PD is sufficient argument to reconsider the indication of renal angiography in a high risk pt with suspected AIRI.

Aged↗

PubMed1990

Follicular dynamics and dominance in Booroola x Finnish Landrace and Booroola x Suffolk ewes heterozygous for the F gene.

To study the influence of the F gene on follicular dynamics and dominance, 2-year-old Booroola x Finnish Landrace (BFL, N = 17) and Booroola x Suffolk (BS, N = 18) ewes were compared with contemporary purebred Finn (FL, N = 18) and Suffolk (S, N = 18) ewes. In Exp. 1, oestrous cycles of ewes were synchronized during the breeding season with progestagen-impregnated sponges. At sponge removal (Day 0), 14 days after insertion, ewes of each of the 4 genetic groups were assigned to Group 1 in which all follicles visible on both ovaries were destroyed by electrocauterization except for the largest (F1) which was marked, Group 2 in which all visible follicles on both ovaries were destroyed, or Group 3 in which the 3 largest follicles of both ovaries were identified as F1, F2 and F3 and marked. At 48 h after treatment (Day 2), follicular growth was evaluated. At Day 0, the mean number of small follicles (1-3 mm) was higher (P less than 0.05) for BS, S and BFL (35.8, 35.1 and 32.9) than FL (24.9) ewes. Large follicles (greater than or equal to 4 mm) were more numerous (P less than 0.05) in FL (3.5) than in BS (2.1) ewes, BFL and S ewes being intermediate. Diameter of the F1 follicle was larger (P less than 0.05) for S (7.6 mm) than FL, BS and BFL (5.8, 5.1 and 5.1 mm) ewes. In Group 1, all F1 follicles marked at Day 0 ovulated at oestrus after sponge removal for BFL, BS and S ewes while in FL ewes, 2 of 6 F1 follicles regressed. In ewes ovulating, only the F1 follicle ovulated except for one S ewe which shed one more ovum. In Group 2, there were no follicles greater than or equal to 4 mm at Day 2 and no ewes ovulated after treatment. In Group 3, the proportion of marked follicles that ovulated was higher for S ewes than in those of the prolific genotypes. The number of follicles not marked at Day 0 but ovulating (compared to the total number of ovulations) was higher in BFL, BS and FL (8/11, 9/13 and 9/13) than S (3/10) ewes. In Exp. 2, prolific (BFL + BS) and non-prolific (S) ewes were compared following destruction of follicles greater than or equal to 3 mm with the F1 left intact (Treatment 1) or destroyed (Treatment 2), 12 days after sponge insertion.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1988

Study of follicular development and heredity of morphological types of ovaries in prepuberal gilts.

Two different morphological types of ovaries ("grape" and "other" types) previously described by microscopic examination were studied on 107 live gilts. The ovarian type and distribution of macroscopic follicles during the prepuberal period were determined at 140, 160 and 180 d of age by laparoscopic examination. The incidence of grape-type (GT) ovaries was higher (P less than .05) at 140 d of age (50.5%) than at 160 d (38.3%) or 180 d (35.5%). At maturity (d 19 of the first postweaning estrus), 37.7% of the ovaries were classified as GT. The proportion of gilts that maintained their initial type (at 140 d of age) at 160 d, 180 d and at maturity was higher (P less than .05) for the gilts having the other-type (OT) ovaries (49% and 25% for OT and GT, respectively). The mean number of small follicles (1 to 3 mm in diameter) was higher (P less than .05) for the OT ovaries at 140 d (71.5 vs 18.0), at 160 d (79.3 vs 26.2) and at 180 d (77.0 vs 32.8). The number of follicles of 4 to 5 mm was higher (P less than .05) for GT ovaries at 140 d (16.4 vs 4.8), at 160 d (20.9 vs 4.8) and at 180 d of age (21.4 vs 5.7). The large follicles (greater than or equal to 6 mm) were more numerous for the GT at 140 d (7.0 vs .3), at 160 d (5.7 vs .5) and at 180 d (4.4 vs .6). No statistical difference was observed at maturity in the distribution of follicles between the two types.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1984

Seasonal changes in breeding activity, testicular size, testosterone concentration and seminal characteristics in rams with long or short breeding season.

Breeding activity (libido), testicular size, testosterone levels and seminal characteristics of 10 DLS adult rams (a population of 1/2 Dorset, 1/4 Leicester and 1/4 Suffolk selected for extended breeding season) were compared with those of 10 adult Suffolk rams. The study lasted 18 mo during which the data were recorded over 30 collection periods. All characteristics varied significantly with the season of the year, being lowest during the summer and highest during the fall. Suffolk rams had higher libido but lower testosterone levels than the DLS rams throughout the study. Testosterone increased earlier and decreased later in the breeding season in DLS compared with Suffolk rams, the interaction breed X period being significant. Testosterone concentration was highly associated with testicular size and libido, accounting for 65 and 28% of the variation in the Suffolk and 37 and 18% in the DLS rams, respectively. Seminal output and quality (motility and percentage of live spermatozoa) were highest in October and November and lowest in April and May. Rams within breeds differed significantly in the seminal characteristics studied. Results of the study showed that selecting the DLS ewes for extended breeding season may have altered the reproductive performance of the rams of that breed.

Animals↗

PubMed1980

A simulation study of truncation selection for a quantitative trait opposed by natural selection.

A quantitative character controlled at one locus with two alleles was submitted to artificial (mass) selection and to three modes of opposing natural selection (directional selection, overdominance and underdominance) in a large random-mating population. The selection response and the limits of the selective process were studied by deterministic simulation. The lifetime of the process was generally between 20 and 100 generations and did not appear to depend on the mode of natural selection. However, depending on the values of the parameters (initial gene frequency, selection intensity, ratio of the effect of the gene to the environmental standard deviation, fitness values) the following outcomes of selection were observed: fixation of the allele favored by artificial selection, stable nontrivial equilibrium, unstable equilibrium and loss of the allele favored by artificial selection. Finally, the results of the simulation were compared to the results of selection experiments.

Alleles↗

PubMedDate not supplied

Genetic analyses of plumage color mutations on the Z chromosome of Japanese quail.

Genetic analyses were performed with four sex-linked plumage color mutations (roux, brown, imperfect albino, and cinnamon) in Japanese quail (Coturnix japonica). Roux and brown quail have similar plumage color, but plumage of roux quail is paler. Pure, F1 and F2 matings were carried out with roux and brown stocks, and 357, 338, and 273 progeny with either roux or brown plumage color were obtained from each mating type, respectively. These allelism tests showed that mutations for roux and brown colors were alleles (*R and *B) from the same locus BR, and that BR*B was dominant over BR*R. Two alleles at the AL locus, AL*A (imperfect albino) and AL*C (cinnamon) were used to estimate the recombination frequency between the BR and AL loci on the Z chromosome. It was estimated to be 38.1+/-1.0% based on 4615 chicks from the test crosses.

Alleles↗

PubMedDate not supplied

Testing homology of loci for two plumage colors, "lavender" and "recessive white," with chicken and Japanese quail hybrids.

Homology for two plumage color loci was studied by hybridization between chickens and Japanese quail. First, chicken-quail hybrids were produced from homozygous "lavender" chicken cocks and "bleu" Japanese quail, and all 30 hybrids had the same parental slate blue plumage color. On the other hand, no hybrids with this plumage were obtained out of 18 progeny from the same cocks and wild-type quail. These results show that the slate blue plumage color is determined by homologous loci in Japanese quail and chickens. Second, all (n = 25) chicken-quail hybrids hatched from homozygous "recessive white" cocks and "recessive white" (n = 8) or "wild-type" (n = 17) quail had the same pattern of plumage color, with white feathers on the ventral face and colored feathers elsewhere. These results indicate that the recessive white mutations are not homologous in Japanese quail and chickens.

Animals↗

PubMedDate not supplied

Effects of two-locus combinations, using the roux, lavender, and beige mutations, on plumage color of Japanese quail.

The interactions between the effects of three plumage color mutations taken two-by-two (sex-linked recessive roux, autosomal recessive lavender, and autosomal dominant beige) were studied in Japanese quail by producing a total of 121 F(1) and 1118 F(2) quail from the three pure stocks. Three new plumage colors were obtained in F(2) quail: roux-diluted beige, cream, and lavender-diluted beige. Two of them, roux-diluted beige (from the roux and beige mutations) and cream (from the roux and lavender mutations) corresponded to double homozygotes or hemizygous birds, and could therefore be used to tag a quail line. On the other hand, an F(3) from F(2) birds with lavender-diluted beige plumage was necessary to show that quail with this plumage color were homozygous for the lavender mutation, but were either homozygous or heterozygous for the beige gene. In all three F(2)s, observed segregation of plumage colors fit simple two-locus Mendelian inheritance.

Animals↗

PubMedDate not supplied

Genetic similarity and relationships of DNA fingerprints with performance and with heterosis in Japanese quail lines from two origins and under reciprocal recurrent or within-line selection for early egg production.

DNA fingerprints of Japanese quail male and female pure line breeders were obtained with probes 33.6, 33.15, and R18.1 and they yielded a total of 59 scoreable bands. Bandsharing (0<BS<1) was calculated within and between six quail lines of two origins, and under reciprocal recurrent (AA and BB), within-line (DD and EE) or no (PP and FF) selection. Twenty one pair types were compared. BS was 0.30 higher within line than between lines. BS with the control line was smaller for reciprocal recurrent selection lines than for lines under individual selection. Bandsharing between the two reciprocal recurrent selection lines was 0.19 lower than between lines under individual selection. These results indicate that the two selection methods had different effects on the genetic constitution of the lines, in agreement with previous observations made from the analysis of biochemical polymorphisms with the same set of birds. Egg production and weight traits of pure and crossbred progeny from fingerprinted quail were obtained and compared, and a linear relationship with the measure of bandsharing was estimated. No significant regression coefficient of performance on BS was found over all progeny genetic types. Heterosis from individual matings could also be estimated under the two selection methods since the same birds were parents of both pure and crossbred performance-tested quail. The association of heterosis with the difference between BS of parents of the purebreds and BS of parents of their half-sib crossbreds was favourable and significant for early production traits in lines DD and EE, but no relationship was found in lines AA and BB. These results indicate that the high level of heterosis obtained through reciprocal recurrent selection, and the heterosis observed under within-line selection may have, partly at least, a different genetic determinism. Therefore, the relationship of heterosis with BS may also depend on the past history of selection in the lines.

Journal Article↗