Line Birds Research Articles

Effects of sex, strain and type of perch on perching behaviour in the domestic fowl

This paper reports a study of perching behaviour in the domestic fowl, in which the use of various types of perches by both sexes of three strains of pen-housed, 15-week-old chickens (‘S’ line, White Leghorn type; ‘T’ line, derived from a Rhode Island Red × Light Sussex cross; ‘J’ line, Brown Leghorn) was compared. The perching variables tested were the height and shape of the perch and the type of material (wood or wire) from which it was constructed. A preliminary experiment indicated that there was no avoidance of those areas of the pens in which the perches were subsequently placed. Both sexes used the perches equally, but strain was an important factor affecting perching behaviour. Birds of the ‘J’ line almost completely failed to use high perches, but usage was greater in ‘T’-line and greatest in ‘S’-line birds. These strain differences were not due to weight disparity or to social pressure. Individual preferences were observed. Some birds perched (perchers) where-as others did not (non-perchers). Repeated exposure increased the time spent on the perch by perchers but did not convert non-perchers into perchers. The type of material (wood or wire) from which the perches were constructed had little effect on behaviour. Low perches were used more than high ones, although they were never attractive, and square perches were used considerably more than lengths of wood. There were no significant preferences for wire or litter in ‘S’-line and ‘T’-line birds but ‘J’-line birds avoided wire. The welfare implications of these results are interesting. Low levels of perching on the length of wood, which is the type of perch most commonly used in semi-intensive housing, suggest that more appropriate perches could be designed. Although wire floors are commonly considered undesirable, ‘S’- and ‘T’-line birds showed no avoidance of wire. The results suggest that perching has a high genetic variance and, therefore, to keep, in line with industrial trends, it should be possible to select for birds which do and which do not perch.

Correlated Responses for Lipogenesis and Adipose Tissue Cellularity in Chickens Selected for Body Weight Gain, Food Consumption, and Food Conversion Efficiency

Cellularity of the abdominal fat pad and lipogenesis in the liver were studied in 9-week-old chickens after eight generations of selection for increased body weight gain (line W), increased food consumption (Line F), decreased food conversion ratio (line E), or at random (line C). The average volume of the adipose cells in the abdominal fat pad was greatest in the birds of line F and smallest in birds of line E. Differences in the number of adipose cells in this fat depot in birds from all the lines can be largely attributed to differences in growth rate. Lipogenesis, as measured by in vitro incorporation of 14C-glucose into lipid and the activity of NADP-malate dehydrogenase, was highest in birds from line F and lowest in birds from line E. These differences in lipogenesis among groups could not be attributed to differences in food consumption or growth rate. The biochemical basis for differences in lipogenesis among lines is not clear at this stage.

Amino acid transport and intracellular Na + and K + content of chicken erythrocytes genetically selected for high and low leucine transport activity

1. 1. Amino acid transport and intracellular Na + and K + content have been studied in two lines of chickens, one high and the other low uptake, selected for their ability to transport leucine into erythrocytes. 2. 2. Low line birds were less effective in absorbing glycine into erythrocytes than were high line birds, the difference in transport being due to a difference in maximal flux ( V max), but not in apparent affinity for transport sites ( k t ). 3. 3. In contrast to glycine uptake, the greater ability of the high line to absorb lysine was found to be due to a difference in both V max and K t . 4. 4. High line erythrocytes were also observed to contain slightly more K + (about 5%) and about 20% less Na + than low line erythrocytes. 5. 5. These results are discussed in terms of the ion dependency of amino acid transport.

Role of Water in Regulating Feed Intake and Feed Efficiency of Broilers

Three trials were conducted to investigate the influence of restricting feed and water intake levels of a fast-growing selected broiler line to the same feed and water intake levels of a nonselected line and to investigate the relationship of water/feed ratios to feed conversion (feed/gain) ratios. The water intake of birds from the selected line on feed restriction was similar to that of birds from the selected line not on feed restriction from 1 to 14 days. However, restriction of water intake of selected line birds resulted in feed intake similar to that of nonselected line birds. From 1 to 14 days, feed conversions of the feed-restricted selected line birds were similar to those of the selected line birds not on feed restriction. Feed conversions of the water-restricted selected line birds were similar to those of nonselected line birds. The maximum deviation in water intake between the selected and nonselected lines was observed before the maximum deviation in feed intake between the two lines; and the maximum deviation in feed intake was observed before the maximum deviation in body weight. Data presented indicate that high water/feed ratios are associated with low feed/gain ratios.

Sex and strain comparisons of tonic immobility (“Righting time”) in the domestic fowl and the effects of various methods of induction

Tonic immobility was induced in adult laying hens using different methods and substrates, factors which have shown great variety of response in previous work. The fact that topic immobility was induced in every situation confirms the robust nature of this phenomenon. Placing hens on their backs and restraining them in a U-shaped wooden cradle covered with cloth was the most reliable and consistent method. Not only was the duration of response greatest when this method was used, but less handling, with its possible stressful effects, was required to induce it. There were no significant differences in the latency to the first head movement or in the duration of immobility between adolescent ‘T’ (Rhode Island Red × Light Sussex) and ‘S’ (White Leghorn) lines but both these characteristics were considerably shorter in the ‘J’ line birds (Brown Leghorn). There were no significant sex differences in the duration of tonic immobility but male ‘T’ and ‘S’ line birds showed greater latencies to the first head movement and fewer subsequent alert head movements than females. These results are discussed in terms of sex and strain differences in fearfulness. The varied nomenclature used to describe the immobility reaction is discussed and an alternative term “righting time” is proposed. It is further suggested that the immobility response consists of an inhibitory and an alert stage.

The immunopathology of spontaneously acquired dysgammaglobulinemia in chickens

The acquired immunopathology of lymphoid and parenchymal organs of University of California, Davis (UCD), line 140 White Leghorn chickens, previously demonstrated to have an inherited dysgammaglobulinemia with associated autoimmune phenomena, is described and compared to normal UCD chicken lines 159, 011, and 440. Although, at autopsy, morbid birds had signs of anemia, congestive heart failure, and splenomegaly, the most prominent features were immunologic in origin. Specifically, there was evidence for immune complex disease, including deposition of immunoglobulin in renal glomeruli, vasculitis, and synovitis. However, of particular importance were age-dependent abnormalities of thymus and bursa of 140 but not those of control chickens. Thymi of 1-year-old birds were dramatically enlarged with microscopic appearance of both hyperplasia and thymoma; the thymi of birds less than 6 months of age were normal. In contrast, bursa from neonatal birds of line 140 but not those of control chickens were markedly underdeveloped and revealed cystic degeneration of bursal epithelium. Furthermore, the size of the bursa and the mitotic index of bursacytes of line 140 were significantly reduced compared to controls. Similarly, although the primary response to SRBC and Brucella antigen was of comparable magnitude in young line 140 and control birds, the percentage of mercaptoethanol-resistant secondary response was lower in line 140 animals. This anomaly of line 140 bursa is unique and suggests that this syndrome of inherited acquired dysgammaglobulinemia of birds, and perhaps acquired agammaglobulinemia of humans, is due to a primary maturational defect of bursa.

Influence of the Interval of Shell Deposition on Eggshell Quality

After selection for three generations, thick- and thin-shelled lines of Single Comb White Leghorns (SCWL) were developed which produced eggs having means of 10.7 and 7.9% shell, respectively, at twleve months of age. The average time interval between ovipositions of the first and second eggs in a laying cycle at 16 months of age was 27 hr 20 min for the thick-shelled line and 27 hr 35 min for the thin-shelled line, respectively. Through digital palpation, in utero times were determined at 17 months of age. Eggs from birds of the thick-shelled line spent an average of 20 hr 5 min and those from birds of the thin-shelled line spent 19 hr 38 min in the shell gland. The percent shell was 9.7 and 7.0 for the thick- and thin-shelled lines, respectively. It is concluded that the two lines differ in shell quality because of differences in the rate of shell deposition.

Testosterone-induced precocious sexual behavior in chickens differing in adult mating frequency

Precocious adult sexual behavior was determined for chicks from two lines of chickens selected bidirectionally for adult mating frequency. Three-day-old chicks were injected with either 0 or 12.5 mg testosterone cypionate (TC) in sesame oil, and their sexual responses to a hand thrust test (HTT) measured at 10, 12, 14, 16 and 18 days of age. TC stimulated copulation in both the high and low mating line, while birds receiving injections of the vehicle only, failed to copulate. There were differences in precocious sexual behavior between lines at this young age, although further differential maturation of neural tissues mediating mating behavior may occur. Courts, mounts, treads and matings were determined for these same birds at 7 weeks of age, following treatment with 25 mg TC. Differences were found between the lines, with high mating line birds scoring higher than low mating line birds for all behaviors measured. Early treatment with TC, however, had no direct effect on sexual behaviors at this age. Correlations between 7-week behaviors and HTT scores were determined and their possible meanings discussed.

HISTOCOMPATIBILITY OF CHICKENS HOMOZYGOUS AT THE B‐LOCUS ERYTHROCYTE ANTIGEN. I. EFFECT OF B‐LOCUS MATCHING ON SKIN GRAFT SURVIVAL

SUMMARYThe development of four lines of white leghorn birds homozygous at the blood group B‐locus is described. Blood grouping of these birds shows that genes for the A‐locus are still segregating. The survival time of skin grafts exchanged between birds of the same line (B‐locus identical) and of a different line (B‐locus non‐identical) was measured. The mean survival time of skin grafts exchanged between birds of the same line was 11.9 ± 2.6 days whilst that of skin grafts exchanged between birds of a different line was 7.5 ± 1.3 days. The relationship of the B‐locus to the major histocompatibility complex is discussed.

Relationship of Heat Tolerance and Oxygen Consumption in Chickens

Chicks from lines genetically selected for high or low heat tolerance were compared to lines selected for high or low oxygen consumption. Oxygen consumption, survival time, respiration rate, lung capacity and body weight were determined.Selection for high oxygen consumption and high heat tolerance resulted in birds with similar characteristics. The high line birds for both heat tolerance and oxygen consumption had greater oxygen consumption, survival time and lung capacity but lower body weight.

Resistance to Mycoplasma synoviae is Bursal Dependent

Bursectomizing small bursa line birds produced susceptibility to Mycoplasma synoviae. This suggested that M. synoviae is B cell dependent, but does not rule out a T cell effect.

Ovarian Follicular Development in Egg and Growth Lines of Japanese Quail

Ovarian follicular development in a line of quail selected for 14 generations for increased 4-week body weight (mean female mature body weight of about 220 g.) was compared to a control line (mean female mature body weight of about 138 g.). Egg weight and yolk weight were greater in the larger bodied (P line) than in the smaller (C line) birds. Follicular rapid development and rest period were of longer duration in the P line than in the C line in young birds but not in older ones. Significant correlations were noted between yolk weight and egg weight (.88 and .87), and yolk weight and the duration of rapid development (.62 and .47) in both young and older birds, respectively. A correlation of .39 (P<.05) was noted between the duration of rapid development and egg weight in the younger birds only.

Eimeria tenella in Bacteria-Free Chicks of Relatively Susceptible Strains

Eimeria tenella in Bacteria-Free Chicks of Relatively Susceptible Strains

The metabolic activity of bursal and thymic cells.

The O2 uptake of thymic and bursal lymphocytes from large bursa line, (LBL) and small bursa line (SBL) birds was studied in vitro. The O2 consumption of bursa and thymus cells significantly increased from 10-15 weeks of age. With the exception of the 13th week, the O2 consumption was significantly greater for the bursa cells from the LB line. Thymic cells were not affected by sera treatment.Birds were injected 2X a day beginning at hatch for 4 days with 7.5 mg testosterone propionate (TP) or cortisone acetate (CA), 2.5 mg TP or CA, and the carrier solution. The O2 consumption increased at different rates over a 35 day period for the TP and CA groups. Our data suggest TP may increase the metabolism of lymphoid cells, CA does not stimulate directly O2 consumption of bursa cells, and cells reseeding the bursa are metabolically active cells.

In vitro activity of bursal lymphocytes from two lines of chickens

Summary The bursal lymphocytes from 18-day-old embryos or 1-week-old birds of large bursa line (LBL) and small bursa line (SBL) were cultured in Basal Medium Eagle with Hanks Base (BEM). The lymphocytes from the LBL cultured in media without serum showed significant growth in a 24-h period whereas cells from SBL chicks showed no cell increase. This suggests that the bursa of LBL chicks has the greater growth potential and that there may be intrinsic growth differences in bursal cells of the two lines. The addition of ancestral line (a line from which LBL and SBL were developed) serum significantly increased growth of the cells from SBL. On the other hand, serum from SBL chicks significantly reduced the growth of the LBL bursa cells; whereas the LBL serum enhanced the growth of the SBL cells. The results indicate that there is a serum factor which regulates cell replication in the bursa. Further support for the thesis that the difference in growth potential between the bursa cells of the SBL and LBL chicks resides in the internal environment (sera) comes from the O 2 uptake studies. While the O 2 uptake values are similar for bursal cells of the two lines when studied in their own sera, the O 2 consumption of bursal cells of LBL chicks was significantly increased by the addition of SBL serum. The LBL serum had no effect on the oxygen consumption of SBL bursa cells.

Heart Rate Studies with Scaleless Chickens

INTRODUCTIONA NUMBER of single gene mutations in the chicken result in abnormal plumage; reviewed by Abbott (1967). Birds with deficient insulation, are particularly susceptible to subnormal environmental temperatures. By far the most severe feather tract deficiency occurs in the autosomal recessive, scaleless (Abbott and Asmundson, 1957). Selection first for resistance to cold stress and then for increased and decreased numbers of feathers resulted in two lines well separated in degree of feathering (Abbott and Asmundson, 1962; Abbott, 1965). Many scaleless birds in the high feather line (ScHi) are now completely covered with plumage; albeit this remains primarily juvenile in form. Birds from the low feather line (ScLo) are virtually naked. These provide an excellent tool for studies of the many effects of prolonged hypothermic stress.In this study, heart rate and heart size of the two selected scaleless lines were compared with three different sources of normal chickens; Single Comb…

Assessment of resistance to infectious diseases in birds of line selected against neoplasms

As a result of specific selection by CAM-test, two lines of chickens with increased resistance to infection with pathogens of Marek's disease and lymphoid leukemia of the group were created: D-2 - on the basis of Leghorn breed, P-2 - Poltava clay. The D-2 resistance index was 50.5%; P-2 79.3% against control, D-4 - 11.0% and P-37 - 58.8%. Selection by CAM - test helped to increase the bird's resistance to leukemia. When artificially infected with the leukemia virus, subgroups A of the selected lines were probably (at P &lt;0.01) more resistant to leukemia than non-selected. A similar pattern of resistance to leukemia was observed in natural infections.&#x0D; The bird of line D-2 was more resistant to Marek's disease: the percentage of deaths from this disease in it was 7.0, while in line D-4 (initial, unselected) and 15.5% of the initial population (not vaccinated bird). After vaccination, the number of deaths from Marek's disease decreased to 0.11% and 1.33%, respectively, the named lines. Line P-2 did not show a probable increase in resistance to tumors caused by Marek's disease in comparison with control P-1. Lines P-2 and D-2 during specific selection did not reduce their resistance to the most common bacterial pathogens (E. coli, S. pullorum), did not differ from unselected lines on the sensitivity of the main immunocompetent organs to vaccination (La-sota, smallpox vaccine), as well as the introduction of thymus - and bursa-dependent antigens.&#x0D; In most cases, both interbreed and interlinear hybrids have an intermediate inheritance of resistance to infection by oncornaviruses, ie hybrids occupied the middle position between more or less resistant baselines.&#x0D; The hybrid bird, obtained using lines resistant to neoplasms, at the age of 30 weeks had an egg weight of 52-54 g, at the age of 6163 g, and the average for the year - 58-60 g. The egg mass in the best combinations is 14-15 kg. The age of 50% egg production varied significantly depending on the year of the study, the quality of the young and the time of its transfer to poultry houses. Under optimal conditions, the bird reached 50% of egg production at the age of 160-165 days, but the weight of eggs at this age is low - 47.9 - 48.6 g.&#x0D; As a result of tests of the best laying on the initial and middle laying hens revealed a combination of B-7 x D-2, from which for 72 weeks of life received 230 eggs per initial and 244.2 eggs - on the average laying hen at the weight of eggs at the age of 30 weeks 52.7 g and 52 weeks - 63.1 g. However, the preservation of these hybrid chickens was lower by 2.3%, compared with P-2xD-2. The registered death from neoplasm was 0.9% of the initial population against 0.45% in P-2 x D-2.&#x0D; At the same time, chickens of the B-7xD-2 hybrid combination received 9.7 more eggs per average laying hen than other hybrids tested in the same poultry house under the same conditions (250.2 eggs vs. 240.5). A characteristic feature of the tested combinations is their reduced susceptibility to neoplasms, the frequency of registered neoplasms did not exceed 1%, while the rest of the chickens of this poultry departure from the neoplasm was 1.75%, ie 2 times more.

Blood Glutathione Levels and Egg Production in Inbred Lines of Chickens

The blood levels of soluble sulfhydryl compounds—expressed as reduced glutathione—have been determined for a number of mature inbred White Leghorn females using the nitroprusside method of Grunert and Phillips (1951). Significant individual and line differences in blood glutathione levels have been observed in birds of inbred lines 22, 23, and 24 (Stutts etal., 1956).A consideration of the data revealed that the glutathione levels determined on March 17, 1955, in 76 individually caged females in lines 22, 23, 24, and the 22×24 crossline were significantly and negatively correlated (r=−0.34, p <0.01) with the number of eggs produced during the month of March. Considering the egg production and glutathione levels of the 54 birds from inbred lines 22, 23, and 24 only, the correlation was −0.37 (p <0.01). Only 44 of the line 22, 23, and 24 females survived throughout the following two months. However, for the survivors, a …

Effect of Krebiozen on Lymphoid Tumor Transplants in Chickens

INTRODUCTIONA REPORT (Ivy, 1951) was given in Chicago in March, on “Krebiozen, an agent for the treatment of malignant tumors.” The material, Krebiozen, is a biological agent separated from the serum of the horse by Dr. Stephen Durovic, after stimulation of its reticulo endothelial cells. Durovic hypothesized that Krebiozen was the regulator of cellular proliferative activity.The material used in these tests was obtained* in sealed glass ampules, containing 0.01 mg. of the Krebiozen dissolved in 1 cc. of paraffin oil No. 9.EXPERIMENTALRPL strain 16 tumor (Burmester and Prickett, 1945) was chosen as the test inoculum. The tumor material was secured from a pool of the 61st passage of a pectoral muscle lymphoid tumor RPL strain 16. This material was known to produce tumors in practically all birds of line 15 (El Dardiry et al., 1952) which is a line of chickens bred for a number of .

On the Measurement and Inheritance of Sexual Maturity in Turkeys (Meleagris gallopavo)

Statistical analysis of the trapnest records of turkeys extending over seven years shows that date of first egg is a better measure of sexual maturity in turkeys than age at first egg. Date of first egg is little influenced by variation in the time of hatch within the normal hatching season of almost two months, whereas age at first egg is influenced, the later-hatched birds starting to lay when younger than the earlier-hatched birds. Moreover, genetic differences in sexual maturity can more readily be demonstrated with date of first egg than with age at first egg. Selection for early and late sexual maturity was effective in establishing lines that differed significantly in date of first egg. When these lines were crossed the results differed according to which way the cross was made. The progeny of late male x early female laid earlier than the birds in the late-maturing line but later than the progeny of the reciprocal cross. In at least one case, the progeny of the latter (early male x late female) laid just as early as the birds in the early-maturing line. It is concluded from this that sexual maturity in turkeys is determined by both sex-linked and autosomal genes. The body weight of turkeys at the time they lay their first egg is usually near the maximum first-year weight, whereas chickens start to lay three to five months before they reach maximum first-year body weight. It is suggested that physical maturity is a less important factor in determining the onset of egg production in turkeys than in chickens and that turkeys have a higher threshold of response to environmental stimuli than do chickens.