Eggshell of the domestic guinea fowl

1. Physical characteristics of eggs of the domestic guinea fowl, Numida meleagris galeata, were measured and compared with those of its wild counterpart and with other birds using allometric relationships.

2. The shell thickness increased and the area density of pores decreased from the blunt to the pointed end of the egg. During incubation, shell thickness decreased, but the shell diffusive conductance to water vapour (G_H2O) remained constant.

3. Fresh egg mass (m₀), length and breadth of the egg, G_H2O and specific water vapour conductance, spG_H2O (G_H2O per g of m₀ ), were affected by the age of the laying flock.

4. Eggs of the domestic guinea fowl were bigger and heavier than eggs of the wild one.

5. Allometry showed that guinea fowl eggs differ from those of the other birds by their greater shell thickness and density of pores. However spG_H2O was normal, the thickness of the shell being compensated for by a greater density of pores for gas exchanges.     

Capillariasis in a vulture guinea fowl

A case of capillariasis was diagnosed in a 5-yr-old male vulture guinea fowl (Acryllium vulturinum) with clinical signs of weakness, anorexia, and vomition. Necropsy revealed that the bird was severely emaciated and the liver was congested. The entire mucosa of the crop and esophagus was severely thickened as a result of the presence of fibrinonecrotic white plaques mixed with numerous nematodes. Histopathology of the crop and esophagus revealed multifocal areas of necrosis of the mucosa, severe inflammation, and squamous cell hyperplasia. Numerous nematode adults, larvae, and eggs consistent with the morphology of Capillaria sp. were found within the mucosa. The nematodes were identified as Capillaria contorta. Similar cases of capillariasis have been diagnosed in other vulture guinea fowl.     

The strength of guinea fowl (Numida meleagris) egg shells

The strength of guinea fowl egg shells has been studied by piercing and snapping methods and the results were compared with those from the domestic hen.

Guinea fowl egg shells are stronger and thicker than egg shells from the domestic hen and the shells are stronger even after allowing for their greater thickness. The difference in snapping strength between shells of the two species is far greater when the shells are snapped inwards than when they are snapped outwards. Studies of the crystal structure, histological structure and chemical analysis revealed interesting differences between the two types of shell but it was not possible to say which of these differences accounted for the differences in strength.     

Water uptake by eggs of mallards and guinea fowl

The cuticle is the principal barrier to water uptake by the eggs of mallard, guinea fowl and the domestic fowl. The fat present in the cuticle of mallard eggs makes a large contribution to repelling water dropped on to the shell but only a small contribution to resisting water movement into eggs exposed to hydrostatic pressure. Although the thickness of the shells of the eggs of the birds mentioned above varied extensively, there was no obvious correlation of the length of the pore canal with the amount of water taken up by an egg.     

Chemical composition of the Pearl Grey guinea fowl

1. The growth of the chemical components of the body of the Pearl Grey guinea fowl from hatching till 127 days of age was evaluated in this study.

2. The Gompertz equation is suitable to describe the growth of the different chemical components over time.

3. Body and feather fat, respectively, were estimated by subtracting the predicted weights of all other components from those of body and feather weights. This leads to an overestimation of body fat content, and erroneous estimated values for feather fat.     

Adenoviral pancreatitis in guinea fowl (Numida meleagris)

Necrotizing pancreatitis was observed in 2-week-old Guinea fowl submitted for necropsy and histopathology. Intranuclear inclusion bodies seen histologically in acinar epithelium were examined by electron microscopy and found to contain viruses resembling adenovirus. Adenovirus was isolated in embryonated eggs from the pancreata of affected birds. The adenovirus isolated was not neutralized by chicken antisera developed against 10 known serotypes of group 1 avian adenoviruses.     

Optimum incubation conditions of the domestic guinea fowl egg

1. During artificial incubation of 8000 guinea fowl eggs, the effects of temperature, relative humidity, rate of inflowing air and age of the laying flocks were determined.

2. Total duration of incubation was divided into setter (0 to 24 days) and hatcher (25 to 28 days) periods. Eggs transferred at the end of the setter period, (ET, % of fertile eggs) and hatching rate (HR, % of transferred eggs) were calculated, as well as the total hatching rate expressed as percentage of fertile eggs.

3. In the range 36 to 39°C, temperature affected significantly (P< 0.001) ET and HR, with optima at 37.2 and 37.0°C ± 0.1°C respectively.

4. During incubating period, relative humidity in the range 40 to 64% (water vapour partial pressure, Ph₂o ⁼ 17 to 34 Torr at 36 to 39°C), significantly (P< 0.001) affected the total diffusive water loss and hatchling mass, both expressed as percentage of fresh egg mass. ET was significantly affected by water loss, the highest ET being for water loss of 13.3 ± 0.5%. Optimal relative humidity was calculated to be 48 to 52% (Ph₂o = 23 to 25 Torr at 37.2°G).

5. The rate of inflowing air significantly (P< 0.001) affected HR, with an optimum at 3.1 Lstpd/(h . egg).

6. The age of the laying flock significantly (P< 0.001) increased water loss; this was explained by a parallel increase of the mass specific shell conductance to water vapour.

7. Finally optimum incubation conditions were deduced, giving total hatching rates of 78 to 81% of fertile eggs, improving by 5 to 8% the best results obtained routinely in commercial practice.     

Molecular characterization of MHC class II region in guinea fowl

1. The MHC class II gene was amplified, cloned and sequenced in guinea fowl. 2. The NumeMHC II sequence of 754 nucleotides included complete exon 1 (91 nt), exon 2 (270 nt), exon 3 (282 nt) and exon 4 (110 nt). 3. The size of β(1) and β(2), domains were 89 and 93 amino acids, respectively in guinea fowl. 4. High amino acid variability (38·2%) was observed within guinea fowl in β(1) domain, while in β(2) domain, amino acid variability (6·3%) was low. 5. Among poultry species, the percent amino acid identity between guinea fowl and chicken, quail, pheasant and duck was 38·8, 42·2, 44·4 and 58·8 in β(1) domain; and 13·8, 17·0, 13·8 and 27·6 in β(2) domain, respectively. 6. Sequence alignment with mammalian and avian MHC showed that many of the conserved features of MHC class II glycoprotein was conserved in guinea fowl. 7. Within-species genetic distances (Poisson correction) based on cumulative amino acid variability in β(1) domain and β(2) domains was 0·141 in guinea fowl. 8. Guinea fowl showed low and similar genetic distances with all the poultry species (0·255-0·268) except duck (0·456). 9. Guinea fowl made separate branch within the major cluster having chicken, quail and pheasant, showing equal distance from these poultry species, whereas duck MHC II clustered separately.     

A seminoma in a monorchid guinea fowl (Numida meleagris)

A case of seminoma in a monorchid adult guinea fowl (Numida meleagris) is described. Grossly, a right enlarged testis, which was soft in consistency, and white to pale in colour with few spots of haemorrhages was observed. Histologically, the testicle revealed diffusely spread sheets of tumour cells. The cells were large pleomorphic with eccentrically placed hyperchromic nuclei. Mitotic figures were evident. A scanty fibrous stroma, containing lymphocytes and histiocytes, separating the groups of tumour cells, along with few areas of haemorrhages were observed. Occurrence of seminoma in guinea fowl is unusual and hence reported.     

Helminths of guinea fowl (Numida meleagris) in Bashkir ASSR

Guinea fowl from different regions of Bashkir Autonomous Soviet Socialist Republic (BASSR) were examined for helminths. Of the 547 fowl examined, 451 (82.4%) harboured at least one species of helminth. A total of 56,772 helminths were collected and classified. Of this number seven were found to be trematodes, 25 cestodes and 56,740 nematodes. Five species of helminths were identified. Amongst infected birds, trematodes were present in three (0.7%), cestodes in eight (1.8%) and nematodes in 451 (100%). Of all recorded helminths, the incidence of Heterakis gallinarum (Gmelin, 1790) was highest. Pre-patent periods for seven species of trematodes were observed in guinea fowl for the first time.     

Distribution and depletion of flubendazole and its metabolites in edible tissues of guinea fowl

1. We measured the distribution and depletion of residues of flubendazole and its major metabolites in breast muscle, thigh muscle and liver of guinea fowls during and after oral administration of the veterinary medicine Flubenol 5% at two doses. 2. The guinea fowls were treated orally with normal feed, medicated at doses of 56 and 86 mg per kg feed for 7 successive days. Afterwards, depletion was observed for 8 d. Just before slaughter, body weights were measured. Thigh muscle, breast muscle and liver of three female and three male birds were sampled. The concentrations of the flubendazole-derived residues were determined by a liquid chromatographic-mass spectrometric method. 3. The highest residue concentrations were obtained for the reduced metabolite. With the therapeutic dose, the maximum mean residue concentrations obtained for this compound in thigh muscle, breast muscle and liver were 312, 288 and 1043 microg/kg, respectively. The values for flubendazole, the parent molecule, were 114, 108 and 108 microg/kg, respectively. The residues of the hydrolysed metabolite were negligible in the sampled muscle tissues. After 24 h of depletion, the sum of the residues of parent and metabolites in muscle tissue still exceeded 50 microg/kg. After 8 d of depletion, flubendazole-derived residues at low concentrations could still be measured in both muscle tissues and liver. Generally, the disposition of residues in breast and thigh muscle was comparable. 4. The European Union has not established a maximum residue limit (MRL) for flubendazole in edible tissues of guinea fowl. In contrast, the existing MRLs for other bird species are expressed as the sum of parent flubendazole and its hydrolysed metabolites. An estimated withdrawal period of three days will assure residue safety in the edible tissues of guinea fowl treated with flubendazole at therapeutic dose. After this withdrawal period following treatment of the guinea fowl, the residues were approximately constant, very low and far below the established safe MRL level for other bird species.     

Body Weight increase of indigenous pearl guinea fowl in Nigeria through cross-breeding

1. The performance of the crossbreds of local unimproved Pearl (RBC) and improved local Pearl (SLP) with improved exotic Pearl (EP) were compared with that of the 'purebreds' of the RBC, SLP and EP to 18 weeks of age. 2. The crossbreds of SLP and EP (SLEP) and RBC and EP (RBEP) had higher body weight and efficiency of food utilisation than the local parents. Heterosis was 5.3, 24.3, 1.6 and 1.6% at 0, 6, 12 and 18 weeks of age, respectively, for RBEP and 3.7, 30.8, 11.5 and 8.6% at 0, 6, 12 and 18 weeks of age, respectively, for SLEP. RBEP was 14.5, 98.8, 35.1, and 36.2% superior to RBC at 0, 6, 12 and 18 weeks of age, respectively. SLEP was also 22.0, 98.7, 41.7 and 41.1% superior to SLP at 0, 6, 12 and 18 weeks of age, respectively. Efficiency of food utilisation improved by 20.4% in RBEP and 24.2% in SLEP. The crossbreds were however inferior to EP in terms of weight gain and efficiency of food utilisation. 3. Evidence from this study indicated that crossing the local Pearl guinea fowl with the faster-growing exotic stock is capable of rapidly improving the body weight of the indigenous guinea fowl and hence its usefulness as a source of meat in Nigeria.