Molecular weight and amino acid composition of fowl delta‐globulin

1. The molecular weight of delta‐globulin was estimated chromato‐graphically to be about 10,700 daltons.

2. Ultracentrifuge experiments at 2.7 × 10⁵ g gave values of s _{20, W} = (1.49 + 0.16C) × 10^?13 s for the sedimentation coefficient and D_{20 w} = (1.12 + 0.19c) × 10^?6 cm² s^?1 for the diffusion coefficient, c being the protein concentration (g/100 ml).

3. According to the Svedberg equation, these imply a molecular weight of 12,470 daltons, assuming [v_bar] = 0.74 ml/g.

4. Using refractometer measurements of protein concentration it was found that E ^1% _1cm (278 nm) = 5.57 at pH 7.8.

5. From the ultraviolet absorption spectrum of the protein in 0.1 N NaOH it was concluded that the molecule probably contains four tyrosine residues and no tryptophan.

6. On this basis a revised amino acid composition is given.     

Pencilled and double‐laced plumage pattern phenotypes in the domestic fowl

1. An investigation was conducted among the progeny from crosses between Partridge Wyandotte and Indian Game bantams into the relationship between two plumage pattern phenotypes, pencilling and double lacing.

2. The F₂ generation consisted of 5 phenotypes, three of which could be attributed to the effect of Pg in the absence of Ml. The other two phenotypes were double lacing and an intermediary between double lacing and pencilling, with presumed genotypes Ml/Ml and Ml/ml+ respectively, indicating that Pg and Lg are one and the same gene for which I retain the symbol Pg.

3. The action of Ml when homozygous is therefore to both add an outer lace and increase the width of the inner rings of eumelanin, so changing pencilling into double lacing.     

Manipulations of germ‐cell populations in the gonad of the fowl

1. Embryos of the domestic fowl have been partially sterilised by injecting the drug busulphan into 24‐h incubated eggs.

2. Some of these embryos were injected with primordial germ cells (PGCs) after 55 h of incubation to attempt to repopulate the gonads.

3. Primordial germ cells transfected with a defective retrovirus containing the reporter gene lac Z were shown to settle in these sterilised gonads.

4. Quantitative histology of 6‐d embryos showed that busulphan produced 75% sterilisation but that PGCs could repopulate these gonads.

5. The technique of producing such germ line chimaeras is of value in studying cell kinetics, gonad differentiation and the production of transgenics.     

Laced and double‐laced plumage pattern phenotypes of the domestic fowl

1. An investigation was conducted among the progeny from crosses between Gold‐Laced Wyandotte and Silver‐Pencilled Wyandotte bantams into the relationship between two plumage pattern pheno‐types, lacing and double‐lacing, both of which are arrangements of eumelanin expressed on a background of phaeomelanic pigmentation.

2. The double‐laced phenotype had been presumed to be caused by the addition to the laced genotype of the gene Pg which causes pencilling. The error of this presumption was demonstrated by the appearance of double‐laced bantams in the F₂ generation of a mating specifically designed to avoid the addition of Pg to the laced genotype.

3. Examination of the F₂ generation demonstrated that the elimination of the eumelanin restrictor gene Co from laced fowl permits the double‐laced phenotype to be manifest.     

Notes on the “wheaten” plumage phenotype of the domestic fowl

1. A study was made using a Light Sussex bantam hen to determine the allele present at the E locus. Conflicting results occurred on mating with different males suggesting the presence in one case of the dominant allele e^Wh and, in the other, of the recessive e^y.

2. Further examination of these apparently conflicting results suggests the possibility that there may be a single gene producing the wheaten phenotype which appears to be dominant if melanin restriction genes are present at other loci, or recessive by interaction with melanin intensifier genes. This gene may also require the presence of down‐diluting gene(s) to produce the wheaten phenotype.     

Chocolate: A sex‐linked recessive plumage colour mutant of the domestic fowl

1. A mating between Black Orpington bantams produced, in addition to blacks, a single female in which the black colouration was replaced by dark chocolate.

2. A mating of the chocolate‐coloured female with a black male, F₂ and backcross matings demonstrated that the chocolate phenotype is caused by a recessive sex‐linked gene to which I assign the symbol ?CHOC.

3. A mating of ‘chocolates’ inter se yielded all chocolate offspring.     

Effects of anticoagulants and storage (4°C) on packed cell volume (PCV) of Nigerian domestic fowl (Gallus domesticus) and guinea fowl (Numida meleagris)

1. Studies were conducted to determine the effects of anticoagulants and storage (4°C) on the PCV of blood samples from Nigerian domestic fowl (DF) and the guinea fowl (GF).

2. Citrate significantly reduced pre‐storage PCV of the DF in comparison with the effect of ethylenediamine tetra‐acetic acid (EDTA).

3. It further decreased (P<0.05) the PCV of the blood of DF and GF over 3 d of storage; this was similar to the effect of EDTA on the PCV of the GF blood.

4. Citrate and oxalates induced haemolysis of blood of the DF and the GF in storage faster than EDTA, but overall the haemolysis was more pronounced from red cells of the GF than from those of the DF.

5. The mean fall in the PCV of the DF was significant at 3.0 mg EDTA/ml of blood in contrast to the fall in the PCV of the GF blood.     

The effect of reserpine on plasma LH concentrations in intact and Gona‐dectomised domestic fowl

1. Reserpine was found to inhibit the secretion of luteinising hormone when injected into intact and gonadectomised fowl at a dose rate which caused heavy sedation.

2. This could indicate that reserpine or its derivatives should not be used for breeding poultry.     

Pathogenicity of two strains of Newcastle disease virus in the grey‐breasted helmet guinea fowl

Summary

Thirty‐five 6‐week‐old guinea fowl keets, seronegative for maternal antibodies to Newcastle disease virus, were infected with Hens strain (33/56) and Kumarov strain of Newcastle disease virus intramucularly (IM) or intranasally (IN).

Clinical signs were first noticed four days post infection (PI) in the group infected al but five days PI in the group infected IN with Hens strain of Newcastle disease virus. These clinical signs were similar in both groups and included anorexia, droopiness, huddling together, greenish diarrhoea and marked cachexia. Prominent nervous signs, including spasms of the head and neck, were observed in groups infected with Hens strain.

The major gross lesions observed were emaciation with prominent keel bone, empty intestinal tract and distended gall bladder in most keets.

The histological lesions were characterised by meningoencephalitis, necrosis and loss of lymphocytes from splenic and lymphoid aggregates. There was muscular degeneration and necrosis in the gizzard and mild pulmonary congestion and oedema in some keets.

Neither gross or microscopic lesions were observed in keels that had received the Kumarov strain.     

3D morphometric study of domestic fowl glomerulus—A scanning electron microscope study of vascular corrosion casts

Microvascularization of domestic fowl kidneys was studied using scanning electron microscopy (SEM) of vascular corrosion casts (VCCs). Two types of nephrons, mammalian-type (MT) and reptilian-type (RT) nephrons and their glomerular structure were analysed quantitatively by 3D morphometry. A significant difference in shape and size between the MT and RT glomeruli was found. The mean diameter of the RT glomeruli was about 56 µm, while that of MT glomeruli was significantly larger, namely about 80 µm. The afferent arterioles in mammalian-type glomeruli usually bifurcated into two lobular branches and formed a complex glomerular capillary network with numerous loops. Reptilian-type glomeruli consisted of a single capillary forming few loops and leaving the glomerulus as efferent arteriole. Diameters of afferent and efferent arteriolar replicas were similar in all three kidney divisions of MT and RT nephrons. The absence of the interconnecting branches between the MT nephron capillaries at the gross inspection suggests that the mammalian-type nephron glomeruli, although more complex than the reptilian type, are not equivalent to those in mammalian kidneys.     

The effect of continuous aeration on the fertility of fowl and Turkey semen stored above 0 °C

1. Fowl and turkey spermatozoa were found to utilise oxygen when stored in tubes at 5 and 10 °G respectively; the storage medium becoming rapidly anaerobic.

2. This aerobic metabolism was encouraged by continuous introduction of air into the semen during storage.

3. Fertility of turkey semen stored at 10 °C for 24 h in a diluent containing glucose was increased 24‐fold by simple aeration and reached 99% of that achieved with fresh semen.

4. Fertilities of greater than 90% were also achieved with fowl semen stored aerated for 48 h at 5 °C in a diluent with or without glucose. The increased fertility on aeration was greater (2.2‐fold) with fowl semen stored in the absence of glucose.     

Egg‐shell water Vapour conductance of the domestic fowl: Comparison between two breeds and their crosses

1. A comparison of egg water loss and egg‐shell water vapour conductance was made between the Sinai fowl (a desert inhabiting breed) and the commercial White Leghorn, together with their reciprocal crossbreds.

2. The Sinai egg was found to be smaller and less permeable to water vapour than the eggs of the Leghorn and crossbreds. The differences were statistically significant.

3. The measured egg‐shell water vapour conductance of the Sinai breed was 25% lower than predicted on the basis of egg mass.

4. The low permeability of the Sinai egg shell might be related to its higher than predicted thickness, which did not interfere with the shell functional pore area.

5. The low water vapour conductance of the Sinai egg shell may reflect adaptations to its dry habitat.     

The structure of the ileo‐caeco‐golic junction of the domestic fowl (Gallus Gallus L.)

1. The structure of the ileo‐caeco‐colic junction of domestic fowl aged from 3 to 12 weeks was investigated by histological techniques and the preparation of latex casts of the lumina.

2. The caeca open ventro‐laterally from the cranial end of the colon. At this level a muscular ring of tissue, formed from the circular muscle of the lamina muscularis of the ileum, projects into the colon lateral to the caecal openings. The location of this muscular ring is discussed in relation to the possible mechanisms of caecal filling.

3. The longitudinal muscle of the lamina muscularis of the caudal region of each caecum is continuous with that of the colon and ileum. The circular muscle of the lamina muscularis of each caecum begins in the muscularis mucosa of the colon at a distance of 1 to 2 mm from the caecal openings. At the level of the caecal openings the musculature is complex, consisting of parts of the lamina muscularis of the colon, caeca and ileum.

4. The openings of the caeca from the colon are narrow and filled with villi. It is suggested that the junction may be involved in filtering material during the filling of the caeca.     

A comparison of the effects of two low‐calcium diets on egg production in the domestic fowl

1. Hens fed on a diet containing 0–05% calcium virtually ceased egg laying (production <4%) whereas those fed on a diet containing 0–5% Ca maintained production at between 20 and 30%.

2. After a return to a normal diet (3% Ca) egg weight, shell weight, ovarian characteristics and oviduct size were of a similar nature in the two groups, though the differences in egg weight, shell weight and shell calcium were significant at the 1 % level.

3. Bone weight and bone ash did not differ significantly between the groups but after a return to normal rations, bone weight and bone ash became higher in the group that had received the 0.05% Ca diet.

4. There were no clinical signs of bone demineralisation during the experiments.     

Differences in egg‐shell quality among the Sinai Bedouin fowl,the commercial white leghorn and their crossbreds

1. A comparison of egg‐shell characteristics was made among the Sinai breed (a desert inhabiting strain), the commercial White Leghorn and their reciprocal crossbreds.

2. The Sinai egg was smaller and its shell thicker and stronger than the Leghorn egg. All the differences were statistically significant.

3. Shell thickness and strength of Leghorn eggs were in accordance with values predicted on the basis of egg mass, while those of the Sinai and the two crosses were considerably higher than predicted.

4. The apparent differences in mean egg mass between Sinai and Leghorn breeds did not explain the differences in egg‐shell quality, neither did the shape index which was very similar among all breeds.

5. The findings suggest that the differences in egg‐shell properties are of a genetic origin.

6. The thick, strong and less permeable egg‐shell of the Sinai breed may reflect adaptations to its arid environmental origin and to incubation in the open.

7. These genetically‐determined egg‐shell characteristics might serve in a future selection for improved egg‐shell quality in poultry.     

Faecal measurements of oestradiol and testosterone allow the non‐invasive estimation of plasma steroid concentrations in the domestic fowl

1. Radioimmunoassays were validated for oestradiol and testosterone in faecal and plasma samples from domestic fowls. Faecal samples were prepared in phosphate buffer. A delay of up to 24 h between defaecation and the freezing of a dropping did not affect faecal steroid concentrations.

2. Differences in plasma concentrations of testosterone and oestradiol between cockerels and hens were clearly reflected in faecal hormone concentrations. Faecal concentrations of oestradiol were low in males and did not overlap with much higher concentrations in females, whereas there was some overlap between the sexes in faecal concentrations of testosterone.

3. The correlation coefficients (r²) between plasma and faecal steroid concentrations were 0.464 for testosterone and 0.852 for oestradiol (log‐transformed data). The coefficients did not increase when the mean hormone concentrations for several droppings produced by each bird during a collection period were used.

4. Faecal steroid concentrations can be used as a measure of plasma steroid concentrations and hence of gonadal activity in chickens. The resolution of the faecal steroid method is less than if plasma measurements were used, but it offers a practical alternative to blood sampling that is non‐invasive and does not require birds to be handled.     

Plumping fluid added to storage medium increases twofold the functional life span of fowl spermatozoa in vitro at 4°C

1. The objective of this study was to examine whether addition of plumping fluid (PF) to Lake's solution (LS) for storage of fowl spermatozoa in vitro at 4°C can prolong survival and improve the quality of spermatozoa.

2. In experiment 1, aliquots of spermatozoa were stored in vitro in LS alone and LS containing 10%, 25%, 50% and 75% (v:v) PF for 0.5, 24, 48, 72, 96 and 120 h at 4°C. After the end of each storage period, spermatozoa were evaluated for their viability, mobility and penetrability. Viability was determined using SYBR-14 and propidium iodide (PI) staining. Mobility was assessed using an Accudenz assay. Penetrability was assessed using spermatozoa-inner perivitelline layer (IPL) interaction assay.

3. In experiment 2, aliquots of spermatozoa were stored in vitro in LS alone and LS containing 25% and 50% (v:v) PF for 0.5, 24, 48 and 72 h at 4°C, and then fertility of the spermatozoa was evaluated using intravaginal artificial insemination (AI) in hens.

4. Storage of spermatozoa in LS alone resulted in loss of viability, mobility, penetrability and fertility within 48 h. In contrast, no loss of viability and penetrability was observed for the spermatozoa stored for 48, 96, 72 and 48 h in LS containing 10%, 25%, 50% and 75% (v:v) PF, respectively. In particular, fertilising capacity was not lost for the spermatozoa stored in the presence of 25% or 50% PF in LS for 48 and 24 h, respectively.

5. In conclusion, these findings demonstrated that in vitro exposure of fowl spermatozoa to PF during hypothermic storage in LS prolonged spermatozoa survival. A 25% (v:v) level of inclusion of PF in LS may be effective for the improvement of viability, penetrability and fertilising ability of the stored spermatozoa.     

The role of histamine and fish meal in the incidence of gizzard erosion and pro‐ventricular abnormalities in the fowl

1. The role of certain fish meals in the production of localised gizzard erosion is confirmed.

2. Lesions typical of gizzard erosion could be produced by the addition of histamine to the diet.

3. The amount of histamine occurring naturally in fish meal depends on the species of fish and the extent and nature of bacterial spoilage.

4. These variables may explain why histamine has not been implicated previously and also why there have not been consistent associations between the condition and geographical source or common factors in bulk consignments of the meal.     

The effect of tonicity of storage media for fowl semen on the occurrence of neck‐bending spermatozoa,fertility and hatchability 1

1. Semen of White Leghorn and Rhode Island Red males was stored for 24 h in diluents hypertonic (460 mOsm/kg H₂O) and isotonic (340 mOsm/kg H₂O) to cock seminal plasma.

2. Compared with the fertility results with semen that had been stored in the hypertonic diluent or was fresh, the fertility of the White Leghorns was not affected after storage in the isotonic diluent; a decrease (P < 0.lb05) was observed, however, using Rhode Island Red semen and isotonic diluent.

3. Fresh RIR semen contained 2.lb31% “neck‐bent spermatozoa” (NBS) which was increased to 4.lb23% and 5.lb76% after dilution in hypertonic and isotonic diluents respectively and stored for 24 h. It is doubtful whether this increase (P < 0.lb05) is the sole reason for the lowered fertility obtained with this breed after storage in the isotonic diluent.