Grey Guinea Research Articles

The fatty acid profile and the quality of breast and leg muscles in female and male pearl gray guinea fowl (Numida meleagris)

The aim of this study was to evaluate the fatty acid (FA) profile and the quality of breast and leg muscles in male and female guinea fowl. In comparison with leg muscles, breast muscles had a higher content of dry matter and total protein, and contained less fat and total collagen (P ≤ 0.05). Sex had no effect on the chemical composition of the studied muscles or the FA profile of intramuscular fat (IMF) (P > 0.05). The IMF of breast muscles was characterized by higher proportions of total saturated fatty acids (SFAs) and polyunsaturated fatty acids (PUFAs), and lower proportions of total unsaturated fatty acids (UFAs) and monounsaturated fatty acids (MUFAs) (P ≤ 0.05) than the IMF of leg muscles. The physicochemical properties of guinea fowl meat were significantly influenced by muscle type (P ≤ 0.05), but not by sex (P > 0.05). Leg muscles were characterized by a higher pH, higher cooking loss, lower lightness (L*), lower drip loss, a higher contribution of redness (a*), and a lower contribution of yellowness (b*) than breast muscles (P ≤ 0.05). The experimental factors had no effect on the sensory attributes or the shear force values of the analyzed muscles (P > 0.05). The unique sensory attributes, high protein content, and low fat content of the analyzed muscles indicate that guinea fowl meat can be a dietary supplement and an addition to other types of meat consumed, especially that most guinea fowl are reared in extensive farming systems that contribute to sustainable food production.

Effect of Variety and Sex on the Carcass and Meat Quality Traits of Guinea Fowl (Numida meleagris L.).

The aim of this study was to evaluate selected parameters of carcass and meat quality in 16-week-old pearl gray and lavender guinea fowl. The birds were raised in summer and fall, in an extensive system. Until 4 weeks of age, the birds were kept indoors, and from week 5 until slaughter they could use outdoor space enclosed by a fence, adjacent to the building. Guinea fowl were fed complete chicken diets: starter (weeks 0-6), grower (weeks 7-12), and finisher (weeks >13). In comparison with lavender guinea fowl, pearl gray birds had higher live weight at slaughter (p = 0.001) and higher carcass weight (p = 0.001). Females, compared with males, had a higher carcass dressing percentage (p ˂ 0.001), lower liver weight (p = 0.008), lower heart weight (p ˂ 0.001), and lower total weight of giblets (p = 0.004). The leg muscles of pearl gray guinea fowl, compared with those of lavender birds, had a higher content of dry matter (p ≤ 0.029). The breast muscles (p ˂ 0.001) and leg muscles (p = 0.017) of lavender guinea fowl contained less fat than the muscles of pearl gray birds. The breast muscles of females had a higher content of dry matter (p = 0.044) and ash (p = 0.016), and lower total collagen content (p = 0.028) than the breast muscles of males. The leg muscles of females were characterized by a higher pH (p ˂ 0.001), and lower cooking loss (p = 0.004) and drip loss (p = 0.005) than the breast muscles of males. The breast muscles of lavender guinea fowl, compared with those of pearl gray birds, were characterized by a higher chroma value (p ˂ 0.001), and a higher contribution of redness (p ˂ 0.001) and yellowness (p = 0.002), and their leg muscles were lighter in color (p ˂ 0.001), with a higher contribution of yellowness (p = 0.041) and a higher hue angle (p = 0.037). The value of chroma (p = 0.004) and the contribution of yellowness (p = 0.002) were higher in the breast muscles of females, compared with males. Neither variety nor sex affected (p > 0.05) the evaluated sensory properties of guinea fowl meat or the proportions of total SFAs, total UFAs, total MUFAs, and total PUFAs in the intramuscular fat (IMF) of breast and leg muscles. Meat from guinea fowl of both analyzed varieties can be an excellent alternative to more popular types of poultry meat due to its high nutritional value and eating quality.

Changes of Selected Egg Quality Traits Depending on the Laying Period of Semi-Intensively Raised Guinea Fowl Hens

The aim of this study was to evaluate selected egg quality traits depending on the laying period of pearl grey guinea fowl hens reared in semi-intensive system. In each of three evaluation terms (the second, fourth and sixth month of laying period) 40 eggs were collected, with the total of 120 eggs were used for quality evaluation. Methods of descriptive analysis and one-way ANOVA were used for data analysis. Overall values of three evaluation terms for egg weight, shell thickness, yolk to albumen ratio, Haugh units and yolk colour were 40.63 ± 0.27 g, 0.50 ± 0.01 mm, 0.58 ± 0.01, 75.37 ± 0.41 and 12.74 ± 0.11, respectively, whereas overall values of shell, albumen and yolk proportion were 15.32 ± 0.15, 53.75 ± 0.16 and 30.94 ± 0.17%, respectively. Significant differences were found for values of egg quality traits depending on the laying period, but the average value was generally comparable with literature data reported for similar rearing conditions for this Guinea fowl variety.

Research on the meat quality of gray Guinea Fowl Numida Meleagris

Research on the meat quality of gray Guinea Fowl Numida Meleagris

Effect of production system and slaughter age on some production traits of guinea fowl: Meat quality and digestive traits

Certain meat quality traits of guinea fowl that were reared in two production systems were determined in this study. Grey guinea fowl were reared in free-range and barn conditions. Birds were slaughtered at 14, 16 and 18 weeks old to determine meat quality traits. Some digestive traits were also determined. The type of production system affected the yellowness of breast meat significantly, and guinea fowl reared in the free-range system had yellower breast meat. The pH of both breast and thigh meat increased at older ages. Water-holding capacity, cooking loss and drip loss of breast and thigh meat were not affected by production system. Drip loss of meat decreased at older slaughter ages. The ratios of digestive system organ weights to body weight mostly decreased at older ages. Keywords: Digestive tract, free-range, meat colour, water holding capacity, pH

Studies Concerning the Dynamics of Productive Indicators on Gray Guinea Fowl (Numida Meleagris)

Growing guinea-fowls is an area of less research activity, although meat and eggs from this species are increasingly sought by consumers around the world. In addition, there is a number of very valuable biological features that makes this sector such attractive. This paper deals with a study on the productive performance of the gray guinea fowl under controlled ambient conditions. The biological material consisted of 50 specimens of guinea-fowls, purchased from a producer in our country. Those guinea fowls were grown according to the species-specific technology, from one day to 77 days. The target indicators were body weight, weight gain, feed consumption and stockholding proportion, determined in accordance with the poultry research methodology. The data were statistically processed using the Anova (Analysis of variance) program. For the gray guinea fowl, the growing period has been divided into three stages of age, differentiated by the protein level of the feed. At the time of population, the body weight of birds was 28.09 ± 0.35 g, and on the day of slaughter (77th day), 1923.76 ± 18.29 g. This weight was achieved with a feed conversion index of 1: 3.64.The gray guinea fowl exhibits good organic resistance and ensures satisfactory meat production under conditions of optimal nutrient feeding.

Effect of varying dietary concentrations of lysine on growth performance of the Pearl Grey guinea fowl

Lysine is the second limiting essential amino acid in poultry nutrition after methionine. Understanding the lysine requirement of poultry is necessary in guiding formulation of least cost diets that effectively meet the nutritional needs of individual birds. The lysine requirement of the Pearl Grey guinea fowl (PGGF) is not known. Therefore, the objective of this study was to assess the appropriate lysine levels required for optimal growth attributes of the PGGF. In a 12-week study, 512 one-day-old Pearl Grey guinea keets were weighed individually and randomly assigned to electrically heated battery brooders. Each battery contained 12 compartments housing 15 birds each. Eight diets fed to the experimental birds consisted of corn-soybean meal and contained 0.80 to 1.22 digestible lysine in 0.06% increments. Feed and water were provided at free choice and the diets were replicated twice. Experimental diets contained 3,100 Kcal metabolizable energy (ME)/kg diet and 23% crude protein (CP), 3,150 ME Kcal ME/kg diet and 21% CP, and 3,100 ME/kg and 17% CP, at zero to 4, 5 to 10, and 11 to 12 weeks of age (WOA), respectively. Birds were provided water ad libitum and a 23:1 and 8:16-hr (light:dark) regimen at zero to 8 and 9 to 12 WOA, respectively. Birds were weighed weekly, and body weight gain, feed consumption, and feed conversions were determined. Data were analyzed using the General Linear Model (GLM) procedures of SAS (2002) with dietary lysine as treatment effect. Females responded better to diets containing 1.04 and 0.8% lysine from hatch to 4 and 5 to 12 WOA, respectively. Males responded better to diets containing 1.10 and 0.8% lysine at hatch to 4 WOA and 5 to 12 WOA, respectively. Therefore, we recommend that PGGF females and males be fed diets containing 1.04 and 1.10%, respectively, at hatch to 4 WOA and 0.80% lysine at 5 to 12 WOA. The diets should be supplied in phases.

Gross and Morphormetry of the Stomach of the Wild Gray Guinea Savannah Squirrel (Sciurus carolinensis)

<p class="jbls"><span lang="EN-GB">Apparently healthy wild gray guinea savannah squirrel, totaling fourteen (14) in number were used for this study. After being captured from the wild, they were kept for two weeks before they were sacrificed. Weight and length of the whole animal, gastrointestinal tract (GIT) and stomach were taken and recorded in gram (g) and centimeter (cm). The mean weight of live animal was 380.04 ± 46.00 g with the GIT counting for 9.97 % of the total body weight. The mean weight and length of the stomach were 1.59 ± 0.36 g and 4.00 ± 0.61 cm, accounting for 0.42 % and 2.94 % respectively. Externally, the stomach was gray-whitish in fresh sample, bean-shaped, covered almost entirely by deep pink like coloured liver ventrally. The interior surface is grayish with non glandular portion around the cardiac area and longitudinally folded glandular portion. Areas of sphincters were recognized as pyloric, toward the intestinal point of attachment to the stomach and cardiac sphincter toward the point of attachment of the esophagus. More folding was noticed toward the pyloric region indicative of food storing and distension capability of the stomach.</span></p>

Effect of Genotype, Sex and Age on Plumage Maturity, and Body Weight of Guinea Fowl (Numida Meleagris)

Abstract The objective of this study was to investigate the effect of genotype and sex on the degree of maturity of the plumage of guinea fowl. The experimental materials comprised 300 slow-growing (Label group) and 300 fast-growing (Standard group) gray guinea fowl. At 12, 14 and 16 weeks of age, 12 birds from each group (six ♂ and six ♀) were slaughtered. Dry feathers were collected from the dorsal area on both sides of the spine, in the interscapular and thoracic region, and from the outer side of the left thigh. The percentages of feathers at five stages of development were determined for each bird: I - pinfeathers covered in sheaths, II - beginning of vane development, III - feathers unsheathed by half of rachis length, IV - feathers unsheathed by more than half of rachis length, V - fully developed vanes and afterfeathers. Feather weight was determined and expressed as a percentage of a bird’s total body weight. At 12 weeks of age, guinea fowl were characterized by the lowest (68.23%) percentage of mature feathers. The percentage of mature feathers increased to 79.36% in week 14 and to 83.20% in week 16. In weeks 14 and 16, the proportion of feather weight in total body weight was significantly lower (9.95 and 10.20%, respectively) than in week 12 (11.88%). Genotype had no effect on feather development, but it influenced feather weight and percentage. Significant (P<0.05) genotype × sex × age interactions were observed in percentage of stage I feathers. Label group guinea fowl were characterized by higher feather weight and a higher proportion of feathers in total body weight than Standard group guinea fowl (267.0 g and 11.01%, 248.9 g and 10.34%, respectively). The percentage of feather weight was lower in females than in males.

Performance and carcass characteristics of guinea fowl fed on dietary Neem (Azadirachta indica) leaf powder as a growth promoter.

The present work aimed at studying growth pattern and carcass traits in pearl grey guinea fowl fed on dietary Neem (Azadirachta indica) leaf powder (NLP) over a period of 12 weeks. Day old guinea fowl keets (n=120) were randomly assigned to four treatment groups, each with 3 replicates. The first treatment was designated as control (T0) in which no supplement was added to the feed, while in treatments T1, T2 and T3, NLP was provided as 1, 2 and 3 g per kg of feed, respectively. The results revealed a significant increase in body weight at 12 weeks; 1229.7 for T1, 1249.8 for T2, and 1266.2 g T3 compared to 1220.0 g for the control group (P<0.05). The results also showed that the supplementation of NLP significantly increased feed intake (P≤0.05) which might be due to the hypoglycaemic activity of Neem. A significant increase was also found in the feed conversion ratio (FCR) of the treated groups over the control, showing that feeding NLP to the treated groups has lowered their residual feed efficiency. The results of the study demonstrate the beneficial effects of supplementing NLP on body weight gain and dressed yield in the treated groups in guinea fowl. NLP is, therefore, suggested to be used as a feed supplement in guinea fowl for higher profitability.

Carcass Composition and Breast Muscle Microstructure in Guinea Fowl (Numida meleagris L.) of Different Origin

Evaluation of dressing percentage and postmortem traits in 14-week-old white and grey guinea fowl, extended with evaluation of breast muscle microstructure, was the aim of the study. Subjects were two varieties of guinea fowl kept in an environmentally controlled house. Birds received complete commercial feeds. At 14 weeks of rearing, their whole carcasses were dissected postmortem. Diameters and percentages of white (alphaW) and red muscle fibres (betaR) were determined based on histological analysis of the musculus pectoralis superficialis. Similar dressing percentage was found in both guinea fowl varieties. At 14 weeks of age, grey guinea fowl had greater body weight, and weight and proportion of leg muscles and wings compared to white guinea fowl. Females of the white variety had greater weight of breast muscles than males. Breast muscle microstructure showed significantly (P < or = 0.05) greater content and diameter of white fibres in grey guinea fowl, and of red fibres in white guinea fowl.

OCENA PODOBIEŃSTWA GENETYCZNEGO MIĘDZY ODMIANĄ IAŁĄ I SZARĄ PERLIC (NUMIDA MELEAGRIS)

The aim of the study was to determine DNA polymorphism between and within white and grey varieties of guinea fowl. At the end of 12 weeks of age, blood was sampled from 13 white and 16 grey guinea fowl, and DNA was isolated. Genetic similarity between the birds was evaluated using RAPD-PCR technique. PCR with five primers was performed in birds studied. The largest number of bands appeared after electrophoresis with AB1-05 and AB1-09 primers, and the smallest number when AB1-08 primer was used. Genetic similarity between the white and grey varieties of guinea fowl, determined as the mean for the primers used, was 0.97. The coefficient of genetic similarity averaged 0.65 within white variety and 0.64 within grey variety.

Effect of floor density on growth performance of Pearl Grey guinea fowl replacement pullets

Little is known of the optimal floor density for the Pearl Grey (PG) guinea fowl pullet. Hence, the objective of this study was to determine the effect of varying floor density on the growth performance of PG guinea fowl pullets. In 3 replicates, 1-d-old guinea keets (n = 786) were weighed individually and randomly assigned to floor pens covered with pine wood shavings at 80, 69, 60, and 53 birds/pen, equivalent to densities of 18, 15.6, 13.6, and 12 birds/m(2), respectively. The birds were allowed feeder space of 2.3, 2.7, 3.1, and 3.5 cm/bird, respectively, and water space of 1.2, 1.4, 1.6, and 1.8 cm/bird, respectively. The photoperiod was 23 h at 0 to 11 wk of age (WOA) and 8 h at 12 to 16 WOA. Birds were fed diets comprising 3,000 and 3,100 kcal of ME/kg of diet at 0 to 4 and 5 to 8 WOA, respectively, and 24% CP. At 9 to 16 WOA, the diets comprised 3,100 kcal of ME/kg and 18% CP. Feed and water were provided for ad libitum consumption. Body weight and feed consumption were measured weekly. Overall, BW gains were higher (P < 0.05) and feed conversion ratios (FCR) were significantly lower in birds reared at a floor density of 18 birds/m(2) than in birds reared on other treatments at 0 to 8 WOA. However, at 9 to 16 WOA, birds at floor densities of 12 birds/m(2)exhibited higher BW gain and feed consumption and lower FCR (P < 0.05) than those at floor densities of 13.6, 15.6, and 18 birds/m(2). Therefore, this study suggests an optimum floor density of 18 and 12 birds/m(2) at 0 to 8 and 9 to 16 WOA, respectively, to achieve the highest possible FCR for the PG guinea fowl replacement pullets.

Effect of Varying Concentrations of Dietary Crude Protein and Metabolizable Energy on Laying Performance of Pearl Grey Guinea Fowl Hens

This study was conducted to evaluate optimum dietary concentrations of ME and CP for egg production performance of the Pearl Gray guinea fowl laying hens. In a 2 x 3 factorial arrangement, 360 Pearl Gray guinea fowl replacement pullets (22 wk of age) were randomly assigned to experimental diets with 2,800 and 2,900 kcal of ME/kg of diet, each containing 14, 16, and 18% CP, respectively. Each dietary treatment was replicated 4 times, and feed and water were provided ad libitum. Experimental birds were raised in laying cages and received 16 h of light throughout the study period. The birds were observed for feed consumption, hen-day egg production (HDEP), egg weight (EW), egg mass (EM), feed conversion ratio, internal egg quality, shell thickness (ST), and BW at the end of each 28-d lay period at 26 to 50 wk of age and at 62 to 86 wk of age. Mortality was recorded as it occurred. Mean HDEP, EW, EM, and ST were higher (P < 0.05) in hens receiving diets with 2,800 kcal of ME/kg of feed than those fed diets containing 2,900 kcal of ME/kg of diet. Hens on 14% CP diets also exhibited higher (P < 0.05) HDEP, EM, and ST than those fed diets containing 16 and 18% CP diets. Mean feed conversion ratio of birds on 2,800 kcal of ME/kg of diet and 14% CP diets were significantly lower than those of hens on other dietary treatments. Differences in feed consumption, EW, internal egg quality, BW, and mortality among dietary ME and CP concentrations were not significant (P > 0.05). Overall, diets composed of 2,800 kcal of ME/kg of diet and 14% CP were utilized more efficiently by the Pearl Gray guinea fowl laying hens at 26 to 50 and 62 to 86 wk of age.

Effect of Varying Metabolizable Energy and Crude Protein Concentrations in Diets of Pearl Gray Guinea Fowl Pullets. 2. Egg Production Performance

The effect of ME and CP concentrations during the growth phase of Pearl Gray guinea fowl pullets on their egg production performance was evaluated. In a 3 × 3 factorial arrangement, five hundred forty 1-d-old Pearl Gray guinea keets were randomly assigned to experimental diets with 2,900, 3,000, and 3,100 kcal of ME/kg of diet; each contained 20, 22, and 24% CP, respectively, from 0 to 8 wk of age (WOA). From 9 to 16 WOA, experimental diets had 3,000, 3,100, and 3,200 kcal of ME/kg of diet, and each contained 17, 19, and 21% CP, respectively. At 17 to 22, 23 to 27, and 28 to 56 WOA, experimental diets were composed of 3,000, 2,900, and 2,800 kcal of ME/kg, and each had 18, 17, and 16% CP, respectively. Dietary treatments were replicated 4 times, and feed and water were provided ad libitum. Body weights were measured weekly from 0 to 22 WOA, and at 28 to 56 WOA the birds were observed for feed consumption, age at first egg, hen-day egg production (HDEP), egg weight, egg mass (EM), feed conversion ratio (FCR), internal egg quality (IEQ), shell thickness (ST), and BW at the end of each 28-d lay period for 7 consecutive periods. Mortality was recorded as it occurred. Overall, BW gains were higher (P < 0.05) in birds fed 3,000 and 3,100 Kcal of ME/kg and 24% CP from 0 to 8 WOA than other dietary treatments. Percentages HDEP, EM, and IEQ were higher (P < 0.05) and FCR was lower (P < 0.05) in pullets fed 3,000 and 3,100 kcal of ME/kg diet at 0 to 8 WOA than those fed 2,900 kcal of ME/kg. Birds on 22 and 24% CP diets at 0 to 8 WOA also exhibited higher HDEP, EM, and lower FCR than those on 20% CP diets. Thus, feeding 3,000 to 3,100 kcal of ME/kg of diet and 22 to 24% CP at 0 to 8 WOA and 3,100 to 3,200 kcal of ME/kg of diet and 19 to 21% CP at 9 to 16 WOA improved HDEP, EM, IEQ, and FCR of Pearl Gray guinea fowl laying pullets at 28 to 56 WOA.

Effect of Varying Metabolizable Energy and Crude Protein Concentrations in Diets of Pearl Gray Guinea Fowl Pullets 1. Growth Performance

This study was undertaken to assess dietary ME and CP concentrations for optimum growth performance of Pearl Gray guinea fowl pullets. In a 3 x 3 factorial arrangement, 540 one-day-old Pearl Gray guinea keets were randomly assigned to experimental diets with 2,900, 3,000, and 3,100 kcal of ME/kg of diet, each containing 20, 22, and 24% CP, respectively, from 0 to 8 wk of age (WOA). From 9 to 16 WOA, these diets were adjusted to contain 3,000, 3,100, and 3,200 kcal of ME/ kg, and each had 17, 19, and 21% CP, respectively. Each dietary treatment was replicated 4 times, and feed and water were provided ad libitum. Body weight and feed consumption were measured weekly. Mortality was recorded as it occurred. Overall, feed consumption was higher in birds on 2,900 and 3,000 kcal of ME/kg of feed and the 24 and 21% CP diets than other dietary treatments at 0 to 8 and 9 to 16 WOA, respectively. When compared with other dietary treatments, cumulative BW gains were higher (P < 0.05) in birds fed 3,000, 3,000 and 3,100, and 3,100 and 3,200 kcal of ME/kg of diet at 2 to 5, 6 to 8, and 9 to 16 WOA, respectively. Pullets receiving 24 and 21% CP diets also exhibited higher BW gains than other dietary treatments at 0 to 8 and 9 to 16 WOA, respectively. Feed conversion ratios were lower (P < 0.05) in birds fed 3,000, 3,100, and both 3,100 and 3,200 kcal of ME/kg of diet at 1 to 5, 6 to 8, and 9 to 16 WOA, respectively, than other dietary treatments. Pullets fed 24% CP diets and either 17 or 19% CP diets exhibited lower (P < 0.05) feed conversion ratios than other dietary treatments at 1 to 8 and 9 to 16 WOA, respectively. Thus, diets comprising 3,000 and 3,100 kcal of ME/kg were utilized more efficiently by the Pearl Gray guinea fowl pullets at 0 to 5 and 5 to 16 WOA, respectively. Also, these birds more efficiently utilized diets containing 24 and 17% CP at 0 to 8 and 9 to 16 WOA, respectively.

Laying Performance of Pearl Gray Guinea Fowl Hens as Affected by Caging Density

The caging density required for optimal egg production by various avian species and varieties is highly variable. Even so, little is known of the required cage density for optimum performance of the laying guinea fowl (Numida meleagris). The objective of this study was to assess the effect of varying cage densities on production performance of pearl gray guinea fowl laying hens. In 3 replicates, 270 pearl gray guinea hens [28 wk of age (WOA)] were weighed individually and randomly assigned to laying cages at densities of 1, 2, and 3 birds/cage, equivalent to 1,394, 697, and 465 cm2/bird, respectively. During the experiment, all birds received a 16-h lighting regimen and were fed the same diet, comprising 2,800 kcal of ME/kg of diet and 16% CP (28 to 59 WOA) and 2,800 kcal of ME/kg of diet and 14% CP (60 to 76 WOA). Feed and water were provided for ad libitum consumption. Experimental birds were observed for feed consumption (FC), hen-day egg production (HDEP), egg weight, egg mass (EM), feed conversion ratio, internal egg quality, and shell thickness at the end of each 28-d lay period for 11 consecutive periods. Mean FC and HDEP decreased significantly with increases in cage density, such that 1,394 > 697 > 465 cm2/bird. Mean EM was also higher (P < 0.05) for birds reared in cages at 1,394 cm2/bird than those reared in cages at 697 and 465 cm2/bird (24.8, 17.4, and 14 g/hen per d, respectively). Feed conversion, HDEP, and EM were negatively correlated with cage density (P < 0.05). Mean feed conversion ratio and percentage of mortality were also lower in birds reared in cages at 1,394 cm2/bird than in other treatment groups. Therefore, laying guinea fowl hens exhibited superior performance when raised at a density of 1 bird/cage (1,394 cm2/bird) than those reared at densities of 2 and 3 birds/cage (697 and 465 cm2/bird, respectively).

Modeling Growth Characteristics of Meat-Type Guinea Fowl

This study was conducted to describe the growth pattern of the French guinea fowl, a meat-type variety. Using BW data from hatch to 9 wk, 2 nonlinear mathematical functions (Gompertz and logistic) were used to estimate growth patterns of the French guinea fowl. The French guinea fowl did not exhibit sexual dimorphism for growth characteristics. From the Gompertz model, the asymptotic BW, growth rate, and age at maximum growth were 2.05 kg, 0.25 kg/wk, and 5.74 wk in males, respectively, and 2.03 kg, 0.25 kg/wk, and 5.72 wk in females, respectively. The ages at maximum growth were 5.75 and 5.74 wk for males and females, respectively, using the logistic model. Differences in asymptotic BW between males and females were not significant in both Gompertz and logistic models. However, the average asymptotic BW of about 1.50 kg for both sexes predicted by the logistic model was below the average predicted BW from the Gompertz model (2.04 kg) at 9 wk. Also, the logistic model overestimated hatching weight (0.06 kg) more than the Gompertz model (0.03 kg), suggesting that the growth pattern of the French guinea fowl is Gompertz. The inverse relationship between the asymptotic weight and age at maximum growth of the French guinea fowl is similar to that of the pearl gray guinea fowl, chickens, quail, and ducks. Understanding the growth characteristics of French guinea fowl will contribute to the efforts of improving production efficiency of this least studied avian species.

Growth Characteristics of Pearl Gray Guinea Fowl as Predicted by the Richards, Gompertz, and Logistic Models

This study was undertaken to describe the growth pattern of the pearl gray Guinea fowl. Using BW data from hatch to 22 wk, 3 nonlinear mathematical functions (Richards, Gompertz, and logistic) were used to estimate growth patterns of the pearl gray guinea fowl. The logistic and Gompertz models are a special case of the Richards model, which has a variable point of inflection defined by the shape or growth trajectory parameter, m. The shape parameter m was 1.08 and 0.98 in males and females, respectively, suggesting that the growth pattern of the pearl gray female guinea fowl is Gompertz. The pearl gray guinea fowl exhibited sexual dimorphism for their growth characteristics. From the Gompertz model, the asymptotic BW, growth rate, and age at maximum growth were 1.62 kg, 0.22 kg/wk, and 6.65 wk in males, respectively, and 1.70 kg, 0.19 kg/wk, and 6.70 wk in females, respectively. The ages at maximum growth were 6.65, 6.47, and 8.12 wk for the Richards, Gompertz, and logistic models, respectively. The pearl gray guinea fowl females have a higher asymptotic BW compared with the males. The average asymptotic BW of about 1.57 kg for both sexes predicted by the logistic model was below the average predicted BW from the Richards (1.66 kg) and Gompertz (1.67 kg) models, respectively, at 22 wk of age. The inverse relationship between the asymptotic weight and both relative growth and age at maximum growth of the pearl gray guinea fowl is similar to that of chickens, quail, and ducks. Success in studying the growth characteristics of guinea fowl will contribute to the efforts of genetically improving this least-studied avian species.

Protein and energy requirements of the Pearl Grey guinea fowl

The ideal protein and effective energy requirements of the growing Pearl Grey guinea fowl up to 20 weeks of age were determined according to the Edinburgh model. Guinea fowl have their highest protein requirements between 5 and 10 weeks of age. Protein requirements of females are lower than those of males up to 10 weeks of age, after which the situation is reversed. Energy requirements from 10 weeks of age are also higher for females than for males.