Strains Of Fowl Research Articles

Evaluation of Loss in Vigour of the Dual Purpose French Guinea Fowl and Their Mixed Genetic Grade in Katsina, Nigeria

The effect of genetic grade (strain) on body weight and body linear measurements of the pure grade dual purpose French guinea fowl strain (116 birds) and their mixed genetic grade (32 birds) was determined using a linear mathematical model. Birds were raised under intensive system in Katsina state. Loss in vigour of the pure grade dual purpose French guinea fowl was calculated by difference. There was a significant (P < 0.05) effect of strain (genetic grade) on body weight and body linear measurements. The pure grade dual purpose French guinea fowl cocks and hens had significantly higher body weight and most body linear measurements than counterpart dual purpose mixed genetic grade guinea fowl cocks and hens. The pure grade dual purpose French guinea fowl cocks and hens had lower coefficients of variation (7.76 and 9.60 %) than the dual purpose guinea fowl cocks and hen mixed genetic grades (13.11 and 13.54 %). The dual purpose mixed genetic grade guinea fowl cocks and hens had longer helmet length than counterpart pure grade dual purpose French guinea cocks and hens. Strain (genetic grade) had no effect on tail length of guinea hens. There were high loss of vigour (56.25 and 57.69 %) of helmet thickness followed by (28.82 and 37.38 %) for body weight of the dual purpose French guinea fowl cocks and hens. Body length (3.76 and 0.56 %) and thigh length (4.22 and 1.85 %) respectively for guinea fowl cocks and hens, were the morphometric traits that had the lowest reduction in vigour among all quantitative traits evaluated. The dual purpose French guinea fowl and their mixed genetic grade had higher body weight than counterpart local guinea fowl strains. Introduction of the dual purpose French guinea fowl into the tropics can aid the diversification of rural poultry production.

Comparison of Egg Production Performance and Egg Quality Traits of Pearl and Black Strains of Guinea Fowl in a Humid Rain-Forest Zone of Nigeria

Data on 272 eggs collected from Pearl (175 eggs) and Black (97 eggs) adult guinea fowl strains were analyzed to determine the egg production performance and egg quality characteristics of the birds. Data generated were analyzed using Student’s t-test. The external egg quality traits measured were egg weight, egg length, egg width, shell weight, shell thickness and egg shape index. Internal egg quality traits studied include egg mass, yolk weight, yolk height, yolk diameter, yolk index, albumen weight, albumen height and albumen diameter and albumen index. The production performance traits measured were egg number and Hen-Day Production (HDP). In addition, weekly body weight of the hens was also recorded. Egg number was significantly (p 0.05) between HDP of the two strains, the Black strain had higher HDP in all the weeks except in weeks 1, 5 and 6. Among the internal traits, albumen diameter differed significantly (p<0.05) between Pearl and Black with mean values of 61.27±2.02 mm and 66.97±1.20 mm, respectively. Effect of strain was not observed for all the other egg traits measured. However, the significant difference (p<0.05) observed for egg number and albumen diameter between the strains suggests at least some degree of genetic dissimilarity, which implies that the strains could be used to improve egg production and egg quality characteristics of guinea fowl in the study region.

Two polymorphic linker histone loci in Guinea fowl erythrocytes

A variable migration of linker histone H1.b and H1.c spots in two-dimensional polyacrylamide gel patterns of total erythrocyte histone H1 has been detected during population screening in two differently plumaged Guinea fowl strains. Alloforms, H1.b1 and H1.b2 as well as H1.c1 and H1.c2, differing in apparent molecular weights tended to form only phenotypes b1 and b2 or c1 and c2 in a white-feathered strain while all phenotypes (b1, b2 and b1b2 or c1, c2 and c1c2, respectively) were present in a black-feathered population. Accordingly, the white-feathered population significantly deviated from the Hardy-Weinberg principle ( chi-square test, d.f = 1, p << 0.001) due to a lack of heterozygotes while the black-feathered population conformed to the Hardy-Weinberg equilibrium ( p > 0.05) at both H1.b and H1.c loci. Differential electrophoretic mobilities of the C-peptides from a partial chemical cleavage (N-bromosuccinimide) or limited enzymatic digestion (α-chymotrypsin and protease V8) of the histone H1.b and H1.c alloforms seem to indicate that altered amino acid sequence segments might be located either at the C-terminal end of globular domain or in the C-terminal domain itself.

Heritabilities and genetic correlations of economic traits in Iranian native fowl and estimated genetic trend and inbreeding coefficients

1. Genetic parameters were estimated in a base population of a closed experimental strain of fowl. Data were obtained on 21 245 Iranian native hens (breeding centre for Fars province) subject to 8 successive generations of selection. This population had been selected for body weight at 12 weeks of age (BW12) and egg number during the first 12 weeks of the laying period (EN), mean egg weight (EW) at weeks 28, 30 and 32, and age at sexual maturity (ASM). 2. The method of multi-traits restricted maximum likelihood with an animal model was used to estimate genetic parameters. Resulting heritabilities for BW12, EN, EW and ASM were 0·68 ± 0·02, 0·40 ± 0·02, 0·64 ± 0·02 and 0·49 ± 0·02, respectively. 3. Genetic correlations between BW12 and EN, EW and ASM were 0·11 ± 0·33, 0·54 ± 0·21 and −0·12 ± 0·03, respectively. Genetic correlations between EN and EW and ASM were −0·09 ± 0·03 and −0·85 ± 0·01, respectively, while between EW and ASM, it was 0·05 ± 0·03. 4. The overall predicted genetic gains, after 7 generations of selection, estimated by the regression coefficients of the breeding value on generation number were equal to 22·7, 0·17, 0·04 and −1·38, for BW12, EN, EW and ASM, respectively. 5. A pedigree file of 21 245 female and male birds was used to calculate inbreeding coefficients and their influence on production and reproduction traits. Average inbreeding coefficients for all birds, inbred birds, female birds and male birds were 0·048, 0·673, 0·055 and 0·047%, respectively. Regression coefficients of BW12, ASM, EN and EW on inbreeding coefficient for all birds were equal to 0·51 ± 0·001, 0·31 ± 0·003, −0·51 ± 0·003 and 0·03 ± 0·001, respectively.

Reciprocal activation of HSF1 and HSF3 in brain and blood tissues: is redundancy developmentally related?

Transcriptional induction of heat-shock genes in response to temperature elevation and other stresses is mediated by heat-shock transcription factors (HSFs). Avian cells express two redundant heat-shock responsive factors, HSF1 and HSF3, which differ in their activation kinetics and threshold induction temperature. Unlike the ubiquitous activation of HSF1, the DNA-binding activity of HSF3 is restricted to undifferentiated avian cells and embryonic tissues. Herein, we report a reciprocal activation of HSF1 and HSF3 in vivo. Whereas HSF1 mediates transcriptional activity only in the brain upon severe heat shock, HSF3 is exclusively activated in blood cells upon light, moderate, and severe heat shock, promoting induction of heat-shock genes. Although not activated, HSF1 is expressed in blood cell nuclei in a granular appearance, suggesting regulation of genes other than heat-shock genes. Intraspecific comparison of heat-sensitive and heat-resistant fowl strains indicates that the unique activation pattern of HSF3 in blood tissue is a general phenomenon, not related to thermal history. Taken together, HSF1 and HSF3 mediate transcriptional activity of adult tissues and differentiated cells in a nonredundant manner. Instead, an exclusive, tissue-specific activation is observed, implying that redundancy may be developmentally related. The physiological and developmental implications are discussed.

Ectothermy and endothermy: evolutionary perspectives of thermoprotection by HSPs

Living organisms respond to heat exposure by selectively expressing heat shock proteins (HSPs). Accumulation of HSPs confers thermotolerance in cell cultures and in ectotherms and is an important component of the heat shock response. This response, however, has not been directly examined in relation to different ;thermal states', namely ectothermy vs endothermy. By using avian development as a model system for transition from ectothermy to endothermy, we show that, in contrast to the ectothermic state, in the endothermic state the organism is more resistant to heat but relies less on HSPs as a first-line thermoprotective mechanism. Moreover, intraspecific, real-time, in vivo measurements in genetically diverse fowl strains relate improvement of thermoresistance in endotherms to improved body temperature (Tb) regulation, with a concomitant delay in the expression of HSPs. The time course of this delay and the Tb at which it occurs imply that the ontogenetic and evolutionary pathways leading to improved thermoresistance may have followed two, apparently non-related, parallel routes--cellular and peripheral (non-cellular). In search of other cellular components that differentially participate in the heat shock response, we revealed a significant expression of fatty acid synthase (FAS) in heat-exposed endotherms but not in ectotherms.

Epididymal lithiasis in roosters and efferent ductule and testicular damage

Epididymal stones have been reported in roosters in the USA and Japan. The cause of this dysfunction, which is associated with low fertility, is not known. The hypothesis of the present study is that a potential cause is the aggressive selection of birds over many centuries based upon female egg laying traits, without concern for potential effects on the male. If this hypothesis is correct, one potential consequence would be the presence of epididymal stones only in domesticated fowl and this observation would be worldwide in distribution. The present study investigated epididymal lithiasis in Brazilian crossbreed roosters and two other fowl strains, in addition to several domestic and wild bird species. The efferent ductules contained stones in 94.3% of the roosters, but stones were absent in all other domestic and wild birds. The stones were irregular in shape, size and colour and consisted mainly of calcium. In affected roosters, the efferent ductules showed epithelial cell vacuolization and sloughing and peritubular mononuclear cell infiltration, culminating with atrophy. Signs of epithelial re-canalization were seen in ductules occluded by abnormal content, such as stones. In the testis, decrease in mass, sloughing of epithelium, mononuclear cell infiltration and tubular atrophy occurred. No correlation was found between the occurrence of stones and a positive test for ELISA IBV (infectious bronchitis virus), or between the number of stones and calcium concentration in water and food, indicating that IBV infection and calcium in the diet were not related to stones formation. This study confirms and extends information about the epididymal lithiasis, which appears to be unique for roosters but to occur around the world. The severity of the lesion points to potentially severe economical impact in the poultry industry.

Epididymal lithiasis in roosters and efferent ductule and testicular damage

Epididymal stones have been reported in roosters in the USA and Japan. The cause of this dysfunction, which is associated with low fertility, is not known. The hypothesis of the present study is that a potential cause is the aggressive selection of birds over many centuries based upon female egg laying traits, without concern for potential effects on the male. If this hypothesis is correct, one potential consequence would be the presence of epididymal stones only in domesticated fowl and this observation would be worldwide in distribution. The present study investigated epididymal lithiasis in Brazilian crossbreed roosters and two other fowl strains, in addition to several domestic and wild bird species. The efferent ductules contained stones in 94.3% of the roosters, but stones were absent in all other domestic and wild birds. The stones were irregular in shape, size and colour and consisted mainly of calcium. In affected roosters, the efferent ductules showed epithelial cell vacuolization and sloughing and peritubular mononuclear cell infiltration, culminating with atrophy. Signs of epithelial re-canalization were seen in ductules occluded by abnormal content, such as stones. In the testis, decrease in mass, sloughing of epithelium, mononuclear cell infiltration and tubular atrophy occurred. No correlation was found between the occurrence of stones and a positive test for ELISA IBV (infectious bronchitis virus), or between the number of stones and calcium concentration in water and food, indicating that IBV infection and calcium in the diet were not related to stones formation. This study confirms and extends information about the epididymal lithiasis, which appears to be unique for roosters but to occur around the world. The severity of the lesion points to potentially severe economical impact in the poultry industry.

Preferences of Growing Fowls for Different Light Intensities in Relation to Age, Strain and Behaviour

AbstractThe preferences of broiler and layer strains of fowl for four different intensities of incandescent luminaire (6, 20, 60 and 200 lux; Osram, 60W, pearl) were tested at 2 and 6 weeks of age. With each strain, four replicates of 12 birds were each allowed to move freely between four compartments illuminated continuously at the different intensities for 6 days. The distribution of light intensities among the compartments was changed daily. After 2 days of conditioning, the birds’ location and behaviour were recorded once every 15min over 23h on each of the remaining 4 days. The other hour was devoted to changing light intensities and refilling the feeders and drinkers. Six, mutually exclusive behaviours were defined: resting, perching, feeding, drinking, litter-directed activity and locomotion.With both strains, most time was spent in the brightest (200 lux) environment at 2 weeks of age. but in the dimmest (6 lux) at 6 weeks. This apparent change in preference was associated only with the two behaviours which took up most time, resting and perching, whereas the highest intensity was consistently preferred for all other behaviours. Older birds thus preferred to be in dim light when they were relatively inactive.The finding that older birds prefer to spend much of their time in a light environment of &lt; 10 lux intensity, depending on behaviour, is contrary to current recommendations that minimum light intensities for broilers and laying hens should be increased to as much as 20 lux. Some variation in the spatial or temporal distribution of ambient light intensity, to provide both dimly (&lt; 10 lux) and brightly (eg &gt; 50 lux) lit environments, might benefit the welfare of older poultry, although further work is needed to establish their optimal light environment.

Use of visual cover by domestic fowl: a Venetian blind effect?

Cover is a structural feature of the environment that animals can use to conceal themselves from predators or conspecifics or to gain shelter from inclement weather. Cover may also form a physical barrier limiting movement. It was hypothesized that domestic fowl,Gallus gallus domesticuswould use visual cover for concealment. Use of cover was examined in two strains of domestic fowl kept indoors in four groups of 110–112 birds each. In each pen, cover was provided by four rigid vertical panels, one in each of four quadrants. Four similar quadrants were without cover. To investigate use of cover for concealment, the four cover structures varied in continuity of visual cover: (1) transparent (0% cover), (2) transparent with four equidistant vertical green stripes (33% cover), (3) transparent with eight such stripes (67% cover) and (4) solid green (100% cover). Scan samples of quadrant use were made weekly when the birds were 24–52 days of age. Both strains of domestic fowl (1) used areas with cover more than areas without cover, (2) showed increased resting and preening behaviour in areas with cover and (3) showed increased use of cover as continuity increased from 0 to 67%. These results could not be explained by thermoregulatory or physical barrier effects of the cover structures. The results are consistent with the hypothesis that a preference for concealment motivates the use of visual cover by domestic fowl, and suggest a ‘Venetian blind’ effect for visually discontinuous security cover.

Degenerative joint disease in poultry — differences in composition and morphology of articular cartilage are associated with strain susceptibility

The morphology and basic biochemical composition of articular cartilage from two strains of fowl Were examined. Broiler breeder fowl are considered susceptible to degenerative joint disease ( DJD); histological examination of one-year-old broiler breeders showed, in some samples, articular cartilage thinning, fibrillation and chondrocyte cluster formation, features considered typical of DJD. Examination of similar samples from laying strain fowl showed only minor age-related changes such as some slight cartilage thinning and very mild fibrillation. The articular cartilage from the broiler breeder birds was significantly more hydrated, with a higher uronic acid content than that of the laying strain birds. In addition, unloaded articular surfaces such as the proximal humerus had significantly higher amounts of uronic acid than the loaded cartilage surfaces of the proximal tarsometatarsus and the distal tibiotarsus; this suggested that the joint loading may have a role in any biochemical differences found between joints and between strains of fowl. These findings concur With other reports in mammals that showed increased hydration and uronic acid in association With early DJD and in models of osteoarthritis ( OA). Thus, despite some differences between avian and mammalian articular cartilage, studies on avian DJD may give insights into mammalian disease.

Comparative development of the antitrochanter in three strains of domestic fowl

Lameness and musculoskeletal disease were more frequent in two strains of broilers (selected [S] and relaxed [R]) than in an unselected layer (J). Defective fibrocartilage accounted for 0·15 of the total area of antitrochanteric cartilage at 29 weeks of age in the S-strain birds. There was more retained hyaline cartilage in the R- and S-strain birds at 15 weeks, and at 22 and 29 weeks there was delayed ossification. Occluded blood vessels, death of chondrocytes and degenerate areas of fibrocartilage occurred only in the broiler strains; they were worse in the S-strain and degenerate fibrocartilage occurred more frequently and in larger amounts. The area, length and depth of cartilage were larger in the heavier strains but the differences were considerably smaller than the difference in their relative bodyweights. The degeneration of the antitrochanter appeared to be associated with a reduction in the blood supply to the underlying hyaline cartilage and with the death of chondrocytes and the degeneration of matrix within the fibrocartilage of the antitrochanter.

Germ-line chimaeras can produce both strains of fowl with high efficiency after partial sterilization.

The drug busulphan is known to be cytotoxic to migrating primordial germ cells (PGCs). A technique is described in which doses of 0, 25, 50 and 250 micrograms busulphan in 40 microliters sesame oil were injected into the yolk of White Leghorn eggs incubated for 0, 24, 48 and 72 h. The percentage survival values of these embryos showed that the older the embryo at the time of injection, the greater the survival. Increasing the dose of busulphan decreased the survival. The percentage of embryos showing abnormalities increased with higher doses of busulphan. The number of germ cells in histological sections from gonads of 16-day embryos was estimated and in embryos treated with 50 micrograms and 250 micrograms busulphan the number of germ cells was significantly less than in the controls. Eggs were injected with 50 micrograms busulphan at 24-30 h, and at 50-55 h the embryos received an intravascular injection of a germinal crescent cell suspension containing PGCs from Rhode Island Red embryos. Twenty hatchlings from these experiments were raised to sexual maturity. All these birds were fertile and half of the breeding groups producing offspring from the transferred germ cells at a rate of about 35% of the total. The technique would improve the efficiency of producing transgenic gametes.

Social spacing in domestic fowl under seminatural conditions: the effect of behavioural activity and activity transitions

Males and females of two strains of domestic fowl, a commercial medium hybrid laying strain and a more primitive bantam type of mixed genetic background, were released into a large (110 m × 80 m) outdoor enclosure. The birds formed two single-strain flocks. Observations were made of flock areas, nearest neighbour distances and distances to the outlying individual of each flock. There were significant differences between the strains in all measurements, the bantam flock forming the more cohesive flock with smaller nearest-neighbour distances and shorter distances to the most outlying individual. There was also a significant effect of behavioural activity on spacing behaviour and these trends were the same for both strains. Birds were furthest apart when they were walking, closer when they were ground pecking, even closer when they were standing and closest when they were preening. To investigate this relationship between spacing behaviour and behavioural activity in more detail, another group, this time of the medium hybrid strain only, were released into the same enclosure the following year. In this second experiment, the movements of birds towards and away from each other were found to be associated with behavioural activity transitions. The direction of these movements was significantly correlated to the direction of the activity transition.

Red cell size and various lung arterial measurements in different strains of domestic fowl

Red cell size and various lung arterial measurements were examined in different strains of young commercial broiler and layer fowls. The broilers were: Marshall, Cobb, Ross ‘selected’, Ross ‘relaxed’ and the layers were: Isa Brown, Ross Brown and Hisex Brown. The Ross relaxed bird had a significantly larger red cell than any other strain. Overall, broilers had larger red cells than layers. The internal elastic lamina, a measure of arterial size, was small in the Ross relaxed bird (138 ym) and was at its maximum (163 μm) in the selected Ross strain. The medial area (muscle coat) was least in the Ross relaxed bird (984 μm 2) and greatest in the Cobb strain (1516 μm 2). In some strains there was a slight correlation among birds between red cell and arterial size but not with the medial area. The results appeared to indicate that red cell size may not be the only important correlating factor in the aetiology of pulmonary hypertension in fowls.

Dietary Protein Restriction Stress and Adrenocortical unction: Evidence for Transient and Long-Term Induction of Enhanced Cellular Function*

Previous work has demonstrated that 4-week protein restriction of the domestic fowl (Gallus gallus domesticus) increases both adrenocortical cell sensitivity to ACTH and corticosteroidogenic capacity. In the present study we examined the transience (study 1) and the persistence (study 2) of this effect of protein restriction. In study 1, two strains of domestic fowl were used: a slower-growing White Leghorn strain and a faster-growing Cobb broiler strain. Cockerels (2 weeks old) were fed isocaloric diets containing either low (L; 5% or 8%) or control (C; 20%) levels of soy protein for 2 weeks, and then were either switched to the alternate diet (C-L, L-C) or maintained on the initial diet (C-C, L-L) for an additional 2 weeks. Cockerels were killed at 6 weeks of age. In study 2, White Leghorn cockerels (2 weeks old) were fed either diet for 4 weeks and then switched to or maintained on the control diet for an additional 4 weeks (i.e. C vs. restriction followed by repletion). In this study cockerels were killed at 10 weeks of age. In both studies highly enriched populations of adrenocortical cells were isolated from cockerel adrenal glands, and their steroidogenic properties (basal and maximally induced corticosterone and cAMP production; steroidogenic agent ED50 values) were evaluated in 2-h suspension incubations. In study 1, regardless of strain, the greater the length of the restriction period, the greater the magnitude of maximal cellular corticosterone production induced by ACTH; the average value for 4-week restriction (L-L) was 39.5% greater than that for 2-week restriction (L-C, C-L) and 117.5% greater than that for control (C-C). In addition, the value for restriction from 4-6 weeks of age (C-L) was 34% greater than that for restriction from 2-4 weeks of age (L-C), suggesting that the enhancement of maximal ACTH-induced corticosterone production after a 2-week restriction interval might be transient. Although there were no strain differences in the effect of protein restriction on maximal ACTH-induced corticosterone production, there were strain differences in its effect on cellular sensitivity to ACTH, as indicated by the ACTH ED50 values (the lower the ED50 value, the greater tha cellular sensitivity). With the White Leghorn strain, the greater the duration of protein restriction, the greater the adrenocortical cell sensitivity to ACTH; the sensitivity of L-L cells was 3.0 times the sensitivities of L-C and C-L cells and 4.1 times the sensitivity of C-C cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Previous experience with different floors influences choice of peat in a Y-maze by domestic fowl

Chicks of two strains of domestic fowl were reared on either floors of wire (wire reared) or concrete covered with wood shavings with access to peat (litter reared). At 13 weeks of age, the birds were given a choice of wire or peat in a Y-maze. The wire-reared birds tended to choose wire and the litter-reared birds tended to choose peat.

Strain-dependent morphine-induced analgesic and hyperalgesic effects on thermal nociception in domestic fowl (Gallus gallus).

The effects of morphine (30 mg/kg), naloxone (5 mg/kg), and morphine with naloxone on distress vocalizations and thermal nociception were examined in different strains of domestic fowl. Naloxone by itself did not significantly affect vocalizations or thermal nociception. Morphine produced a naloxone-reversible attenuation of vocalizations that was not strain dependent. Morphine produced a strain-dependent analgesic (Rhode Island Red strain) and hyperalgesic (White Leghorn and Cal-White strains) effect on tests of thermal nociception. Both the analgesic and hyperalgesic effects were reversed by naloxone. These opposite effects on thermal nociception may reflect the effects of selective breeding on opioid receptor subtype.

Differential cholinergic influences on the immobility response in various strains of domestic fowl

A series of five experiments examined the effects of two anticholinergic drugs, atropine and scopolamine, on the duration of tonic immobility (TI) and susceptibility to the TI response in both Production Red and White Leghorn chickens (Gallus gallus), in an attempt to resolve previous contradictory findings about the effects of cholinergic manipulations on tonic immobility. These two anticholinergic drugs significantly reduced the duration of TI and, therefore, supported the conclusion that cholinergic systems are involved with the immobility response. However, the effects of these drugs on TI differed depending on the age, strain, local population, and handling experience of the individual birds.

Plasma concentrations of somatomedin-C in hypophysectomized, dwarf and intact growing domestic fowl as determined by heterologous radioimmunoassay.

The application of a human somatomedin-C radioimmunoassay for the determination of somatomedin-C in chicken plasma has been examined. Parallel inhibition of binding of 125I-labelled somatomedin-C to antisera raised against somatomedin-C was observed with acid-treated human and chicken plasma. The concentration of immunoreactive (IR)-somatomedin-C in the plasma of the domestic fowl appears to be GH dependent. Plasma concentrations of IR-somatomedin-C were reduced after hypophysectomy and partially restored by replacement therapy with chicken GH. The age/development pattern of circulating concentrations of IR-somatomedin-C has been determined in normal and dwarf strains of domestic fowl. Increases in the plasma concentration of IR-somatomedin-C were observed between 1 and 6 weeks of age in control male domestic fowl of either heavy (broiler type) or light (White Leghorn) strains. Thereafter, the plasma concentrations of IR-somatomedin-C remained constant in the heavy strain birds but declined in White Leghorn chicks. Plasma concentrations of IR-somatomedin-C were reduced in sex-linked dwarf chickens, in both light and heavy strains of fowl, but were unaffected in autosomal dwarf chickens.