Effects of season on the reproductive organ and plasma testosterone concentrations in guinea cocks (Numida meleagris)

Abdul-Rahman, Ibn Iddriss; Robinson, Jane E.; Obese, F.Y.; Jeffcoate, I.A.; Awumbila, B.

doi:10.3382/ps/pev342

Cited by 19 publications

(17 citation statements)

References 27 publications

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“…The histological techniques used in the present study have been described previously (de Reviers, 1971a,b;Abdul-Rahman et al, 2016), therefore, only a brief description is given here. The testes (with capsule intact and epididymal region attached) were each divided into two halves.…”

Section: Histological Preparation Cell Identification Stereologicalmentioning

confidence: 99%

“…Tubules tended to elongate with age, and diameters may therefore not be accurate when measured directly. Nonetheless, in tubules with minimum and maximum diameter differences not exceeding 20% (Brillard, 1986), diameters and surface areas were measured in order to compare apparent diameters (diameters measured directly) to actual diameters (diameters derived from the surface area using the formula D = √surface area × 4/π) (Abdul-Rahman et al, 2016, 2017. Lt was expressed in m.…”

Section: Dimensions Of Seminiferous Tubulesmentioning

confidence: 99%

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Testis Size and Asymmetry in the Guinea Fowl (Numida Meleagris): A Test of the Compensation Hypothesis

Abdul-Rahman

Obese

Robinson

2018

Avian Biology Research

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Despite numerous studies on testicular asymmetry in birds, there are still inconsistent reports on the pattern of asymmetry in species belonging to various phylogenetic groups and exhibiting diverse lifestyles. In addition, there is a lack of clarity on whether functional differences exist between the left and right testes despite differences in size, as well as no evidence of naturally occurring compensation in testis size in terrestrial and galliform birds. A study involving 400 Guinea Fowl (Numida meleagris) cocks was conducted to determine asymmetry and compensatory growth in the testes as well as age-related changes in absolute and relative testicular asymmetry. The left testis had significantly higher weight, volume and relative weight than the right testis. Similarly, populations of round spermatids, type I spermatocytes, total germ cell, Sertoli efficiency, actual and apparent seminiferous tubular diameters and testicular sperm production were higher in the left than the right testis. Correlations between the left and right testicular gross anatomical and histological biometric traits were strong and positive. Left biased asymmetry was recorded in the Guinea Fowl. Absolute testicular asymmetry increased with age, but tended to stabilise from 20 weeks of age, while relative testicular asymmetry remained stable throughout. Both absolute and relative testicular asymmetries were higher in breeding than non-breeding males. Compensatory growth was recorded in both testes with no difference in the degree of compensation. The left biased asymmetry observed in the Guinea Fowl was reflected in functional differences between the two testes.

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Section: Histological Preparation Cell Identification Stereologicalmentioning

confidence: 99%

Section: Dimensions Of Seminiferous Tubulesmentioning

confidence: 99%

Testis Size and Asymmetry in the Guinea Fowl (Numida Meleagris): A Test of the Compensation Hypothesis

Abdul-Rahman

Obese

Robinson

2018

Avian Biology Research

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“…Where demand is not met as occurs during the rainy season, the wholesalers travel far, assembling birds from the few farmers willing to sell to meet the demand of their clients [29]. The seasonal availability of products may be related to the seasonal breeding habit of these birds [30][31], as farmers are usually unwilling to sell their birds during the breeding season, which occurs in the rainy season. X2 (5%) = 44.7, df = 2, p = 0.064…”

Section: Resultsmentioning

confidence: 99%

Guinea fowl (Numida meliagris) value chain: Preferences and constraints of consumers

Abdul-Rahman¹,

Angsongna²,

Baba³

2019

AJFAND

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Despite the increasing production of guinea fowls in most African countries, consumer preference information and constraints remain largely undocumented. A study involving 200 consumers and 50 processors was done in the Tamale metropolis to assess their respective roles in the guinea fowl value chain. Consumers were categorised into households and institutions. Household consumers were further partitioned into lower-, middle-and upper-income classes. Most (99%) of the consumers interviewed ranked guinea fowl meat as their most preferred poultry product, and taste was ranked as the top most reason for their choice. A large proportion of household and institutional consumers ate guinea fowl meat once monthly (42%) or weekly (33.5%). All categories of consumers preferred farmers as the source of birds for consumption. Live birds were the most preferred form of guinea fowl by both consumers and processors. Most (93.7%) consumers indicated that there are seasonal fluctuations in the price of guinea fowl leading to the use of products that are substitutes for guinea fowl. Price instability was ranked as the top constraint to guinea fowl consumption in the metropolis. Beef was the cheapest fresh guaranteed halal meat product on the market, and the prices of beef, mutton and chevon were the most stable, while that of the guinea fowl was the least stable. Institutional consumers used guinea fowls more frequently (p<0.05) as compared to household consumers. Similarly, upper-and middle-income households, as well as male heads of households used guinea fowls more frequently (p<0.05) as compared to low-income and female heads of households. Most (60%) processors processed birds either once weekly or monthly. The level of education of the heads of households had no effect (p>0.05) on the frequency of use of guinea fowl meat. There was also no difference between male and female heads of households in preference for guinea fowl packaging. Similarly, household consumers of all income classes chose all packaging of guinea fowl equally, while households and processors ranked friends as the top source of food safety information and institutional consumers ranked television as the number one source of food safety information. Guinea fowls have huge market potential, but the seasonal price fluctuations still remain a challenge. Additionally, the preference for live birds among institutional and household consumers seem to be related to uncertainty about conforming to halal standards in slaughter of birds by processors and poor meat handling and hygiene standards among processors in the metropolis.

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“…The zone has nearly equal amounts of light and darkness (12L:12D) within a 24 h period throughout the year. The guinea fowl used in the present study is native to this location, and breeds more intensely between April and August during rainy season, and declines when the season is receding between August and October ( Abdul-Rahman, Robinson, Obese, Jeffcoate, & Awumbila, 2016b ).…”

Section: Methodsmentioning

confidence: 99%

“…The testosterone assay had been previously validated for guinea fowl ( Abdul-Rahman et al., 2016b ). The assay was a RIA using tritiated tracer (Amersham Int., Amersham, Bucks, UK) and a procedure as originally described by Sheffield and O'Shaughnessy (1989) .…”

Section: Methodsmentioning

confidence: 99%

Age-related changes in the gross anatomy of the reproductive organs, and associated steroid hormone profiles in male and female guinea fowls (Numida meleagris)

Abdul-Rahman

Jeffcoate

Obese

2018

Veterinary and Animal Science

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Owing to the paucity of information on the reproductive biology of guinea fowls, a study involving a total of 132 birds was conducted, and this documented the developmental changes in the gross anatomy of the reproductive organs of males and females from hatching until 32 weeks of age (WOA), and associated steroid hormone changes. Testicular anatomical biometric traits increased significantly ( p < 0.0001) from 8 WOA, and stabilised between 16 and 20 WOA, while peripheral testosterone concentration peaked at 20 WOA. Correlations among all testicular biometric characteristics were strong and positive ( p < 0.0001). Similarly peripheral testosterone concentrations strongly ( p < 0.01) and positively correlated with all the testicular anatomical biometric traits. In the female guinea fowl, the ovary and oviduct were discernible and measurable at hatching. Significant ( p < 0.0001) increases were seen in ovarian and relative ovarian weights, and oviducal weights and lengths between 24 and 28 WOA. Plasma 17β-oestradiol decreased gradually to a very minimum at 16 WOA, and then began to increase gradually until 28 WOA when it plateaued. Peripheral progesterone concentrations on the other hand increased gradually from 4 WOA and peaked at 12 WOA, and then fluctuated considerably thereafter. Correlations among ovarian/oviducal anatomical parameters were strong ( p < 0.0001) and positive. Similarly, peripheral oestradiol concentrations strongly ( p < 0.0001) and positively correlated with all ovarian/oviducal anatomical parameters. Testicular anatomical biometric traits stabilised between 16 and 20 WOA, coinciding with peak peripheral testosterone concentrations, while ovarian/oviducal parameters recorded huge increases between 24 and 28 WOA, and may be under the influence of oestradiol.

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Effects of season on the reproductive organ and plasma testosterone concentrations in guinea cocks (Numida meleagris)

Cited by 19 publications

References 27 publications

Testis Size and Asymmetry in the Guinea Fowl (Numida Meleagris): A Test of the Compensation Hypothesis

Testis Size and Asymmetry in the Guinea Fowl (Numida Meleagris): A Test of the Compensation Hypothesis

Guinea fowl (Numida meliagris) value chain: Preferences and constraints of consumers

Age-related changes in the gross anatomy of the reproductive organs, and associated steroid hormone profiles in male and female guinea fowls (Numida meleagris)

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