This study was conducted in urban and rural areas in the Man department of western Côte d’Ivoire. The Department of Man is located in the Tonkpi region, western area of country. This department is composed of 11 sub-prefectures: Bogouiné, Fagnampleu, Gbangbegouiné-Yati, Logoualé, Man, Podiagouiné, Sandougou-Soba, Sangouiné, Yapleu, Zagoué, and Ziogouiné [ 7 ]. The department is bordered by the Biankouma department to the north, Bangolo to the south, Danané to the west, and Facobly and Kouibly to the east. With rainfall exceeding 1500 mm per year [ 8 ], Man is a fairly humid area due to its mountainous ground and forest covering ( Figure 1 ).

Surveys were conducted to identify and select farmers whose animals were studied. Criteria for identification and selection were established for this purpose. These included the accessibility of the farmer’s farm in all seasons, having a herd of at least three (3) goats, and involvement in or support for data collection. A total of 20 villages in the Man Department and 10 neighbourhoods in Man City were visited for 30 sites ( Figure 1 ). In each neighbourhood, only one (1) farmer was selected for the study. Two farmers in two villages whose goats were kept in enclosures were selected. As for the 18 other villages, one (1) farmer was also chosen for the study to reduce the risk of sampling related animals, given that the livestock are free-ranging. A total of 30 farmers were included in this study.

A total of 90 goats (06 bucks and 84 does) with a minimum age of one year in five sites were sampled, with a maximum of four animals in each herd used for body measurements to avoid issues in the two provinces. The age of the goats was estimated using their teeth. Eight quantitatives and nine qualitatives traits were assessed per herd, with a maximum of four animals per herd, following the FAO/ISAG guidelines for goat characterization [ 9 ] ( Figure 2 ).

The collected data were recorded in a Microsoft Excel spreadsheet and analyzed using R-3.6.2 software. Normality of the distribution of values and similarity of variances for quantitative variables in the goat subpopulations were verified using the Shapiro-Wilk and Bartlett tests. Various representing morphobiometric characteristics were analyzed using multivariate analysis of variance (ANOVA) to assess their combined influence on the separation of goat subpopulations. Subsequent ANOVA tests were then conducted to examine the effect of each individual characteristic on subpopulation differentiation. A t-test was then used to compare the mean values of male and female goat subpopulations respectively in urban and rural environments. Pearson’s correlation coefficients were estimated between morphometric parameters. The significance threshold for all statistical tests was set for 5%. The structure of the morphological diversity of goats was assessed by Principal Component Analysis (PCA) using the FactomineR and Factoextra packages. The prevalence of qualitative variables was expressed in terms of percentages. These proportions were compared using the chi-square test. The structure of the morphological diversity of goats linked to qualitative traits was assessed using MCA with the factomineR, ggplot2, and Ade4 packages. This analysis was performed by turning the 10 qualitative traits’ data matrix into hclust objects. The fastcluster package was used to determine the optimal group number.

The piebald coat is really in most of the goats sampled in this study. It was observed in 77.78% in the whole-breed with 66.67% of males and 78.57% of females exhibiting this coat pattern. Only 22.22% of the study breed had a solid coat. Males with this pattern represent 33.33% of the breed studied and females 21.43%. The predominant solid coat is the wild coat, which is present in 6.67% of the breed studied, with frequencies of 16.67% in males and 5.95% in females. The wild coat is followed by the black coat, which appears in 5.56% of all individuals studied, with 16.67% of males and 4.77% of females exhibiting this phenotype. Black, tan, fawn, and buff coats were not observed in males. The most common coats in the studied breed were black and fawn piebald, which were observed in 27.78% of the individuals. Black and fawn piebald coats had frequencies of 16.67% and 33.33% in males, respectively.

These coats were present, respectively at frequencies of 28.57% and 27.38% for black and fawn piebald coats, respectively. The wild piebald coat was the most commonly observed coat among the goats studied after the black piebald and chamois piebald coats, with a frequency of 16.67% and 8.33% among male and female individuals, respectively. The coat, front mantle, black and tan piebald, and diluted buff piebald were not observed in male goats. All male goats had curved horns, compared with 94.05% females. Straight horns were not observed in males. Only 5.95% of the females had straight horns. Almost all the goats studied had short hair (96.67%). Only 3.33% of the study breed had medium-length hair. Regarding the nose bridge, 83.33% of the males in this study had a straight nose bridge, compared with 94.05% of the females. A concave nose bridge was observed in 6.67% of the animals studied, with 16.67% of males and 5.95% of females exhibiting this phenotype ( Table 1 ; Figure 3 ).

The numbers in parentheses indicate the test frequencies. The values in parentheses represent the number of individuals characterized.

All male individuals in this study had beards, compared with 86.91% of females which did not. Goatees were observed in females (4.76%). All males studied have manes. As for females, 76.19% had one, compared with 23.81% which did not. Only 38.89% of the animals sampled had a dorsal stripe, with 66.67% in males and 36.90% in females ( Table 2 ).

The numbers in parentheses indicate the test frequencies. Values in parentheses represent the number of individuals characterized.

Table 3 shows the results of the analyses of the eight quantitative parameters aimed at highlighting the environmental effect. A comparison of the averages for goats raised in urban and rural environments revealed no significant differences between the two variables. These were the horn length and ear length variables. However, at the 5% threshold, the six variables showed significant differences. These were height at the withers, for which individuals raised in urban areas had an average of 49.52 ± 4.12 cm and those raised in rural areas had an average of 47.43 ± 3.14 cm. The average head lengths measured 14.56 ± 1.27 cm in urban settings and 13.86 ± 1.55 cm in rural settings. The average scapulo-ischial lengths were 55.54 ± 6.13 cm for goats bred in urban areas and 52.37 ± 5.81 cm for those bred in rural areas. For chest circumference (thoracic perimeter), individuals raised in urban areas had an average of 73.96 ± 7.47 cm, whereas those raised in rural areas had an average of 68.84 ± 8.31 cm. Finally, for the weight variable, goats reared in urban areas showed an average of 28.82 ± 6.86 cm, whereas those reared in rural areas showed an average of 23.36 ± 7.56 cm. Overall, goats raised in urban areas had higher averages on the six variables than those raised in rural areas ( Table 3 ).

1) Correlation matrix

Figure 4 shows the pearson correlation matrix for all morphobiometric traits. Only correlations with a significant p-value at the 5% threshold were introduced in the figure. This matrix indicates that all correlations were positive. The majority of correlations between the different variables are medium. They ranged from 0.4 to 0.6. The correlations between ear length on the one hand and weight, scapulo-ischial length and head length on the other, and between neck length on the one side and head length and chest circumference on the other, have values of 0.30. Strong correlations were observed between weight and chest circumference (0.95), scapulo-ischial length and chest circumference (0.77), scapulo-ischial length and weight (0.83), total length and chest circumference (0.69) and head length and weight (0.68).

2) Principal component analysis

Figures 5-7 show the PCA results for the entire sample. They were based on eight morphometric measurements of the study area’s animals. The first three axes in the sample have an 82.4% cumulative variance. The first axis explains 59.5% of the total variability, whereas the second explains only 12.7%. The third axis explains 10.2% of the total variability ( Figure 5 ). The variables that contribute most to the formation of the factorial plane consisting of axes 1 and 2 are: ear length (EL), weight (W), height at the withers (HW), and SL. Factorial plane 2 formed by axes 2 and 3 is mainly formed by LCU and LO variables. Generally, active individuals contribute an average amount to the formation of the first three axes, with the exception of two individuals, one from the northern zone and the other from the southern zone, as shown in Figure 6 . Most of the individuals which contributed to axis 3’s formation came from the southern zone. No discrimination in the population was found by PCA, regardless of the plane ( Figure 7 ).

3) Multiple component analysis

The discrimination between the different classes was performed using a partitioning algorithm based on the HI loss criteria. Figure 8 shows the inertia jumps obtained by transforming the qualitative variable matrix into the crust class objects. The analysis of this figure allows us to distinguish the optimum number of groups, which is two. Individuals in our sample are represented as points in two-factor multiple component analysis planes. It consists in factors 1 and 2. The second plane includes factor axes 2 and 3. The two colours observed represent the two groups obtained from the partitioning method. The red and blue individuals represent, respectively individuals in groups 1 and 2, respectively ( Figure 9 ). The first factorial plane representation of individuals clearly divides the studied population into two distinct subgroups. Group 1 consists of 21 individuals, 15 of whose come from urban areas and 6 from rural areas. They are characterised by plain coat patterns and colours ( Table 4 ). The second group consisted in 49 and 20 individuals from urban areas and 20 individuals from rural areas. This group is characterised by a variegated coat pattern and coats of varying colours.