Assessment of commelina species feed use in Konso Zone, Southern Ethiopia: Identification, seasonal characterization, and altitudinal distribution

Abstract

Searching for low-cost, readily available non-conventional feeds is viewed as an alternate measure and solution in resolving feed-related difficulties. This study was conducted to investigate Commelina species feed use in Konso zone, Southern Ethiopia, by identifying available species and characterize seasonal and altitudinal distribution. The data were gathered through focus group discussions and interviews with 195 households drawn randomly from 15 villages. Five Commelina spp.; Commelina benghalensis, Commelina imberbis, Commelina diffusa, Commelina albescens, and Commelina africana were identified in the study area. C. diffusa was available year-round (88.71%) at low and mid altitudes, whereas all others show diminishing pattern with dry season. C. benghalensis, C. imberbis and C. diffusa were found in low and mid altitudes, whereas C. africana and C. albescence were found only in low altitude. Availability and distribution of commelina spp. in the study area shows variability with seasonal and altitudinal changes. The wider feed usage by livestock keepers across all the corners of the area, combined with the species’ proclivity to grow as friendly alley crops on farmland, suggests that the value of C. benghalensis and C. imberbis may extend beyond feed use. Agricultural experts must transfer intercropping trend of C. benghalensis, and C. imberbis with food crops to farmers who lack it. Nutritional quality of the species should be conducted to have a clear picture about feed value of the plants.

Keywords:

• Altitudinal distribution
• Commelina species
• Ethiopia
• Feed use
• Konso

PUBLIC INTEREST STATEMENT

Seasonal variability of feed resources, a scarcity of feed ingredients and high prices of feed ingredients were among Ethiopia’s significant issues in the feed business. Searching for low-cost, readily available non-conventional feeds (NCF) was viewed as an alternate measure and solution in resolving feed-related difficulties. Numerous species of Commelina species were known for their feed use for many livestock species in the Konso area, southern Ethiopia. On the other hand, the species’ feed value has received scant attention and is not extensively documented by scientists. So, this study was conducted to investigate Commelina species’ feed use, emphasizing on identification, seasonal characterization, and altitudinal distribution in Konso Zone, Southern.

1. Introduction

Domestic demand for livestock-derived food (LDF) products is increasing dramatically as a result of fast-growing population, increased urbanization, and rising earnings (Shapiro et al., 2017). In Ethiopia, animal-based food consumption is quickly expanding, with projections of a 165 percent increase in 2030 compared to 2011 (Getachew et al., 2018). This anticipated increase represents a golden opportunity for the livestock industry, implying that significant investment is necessary (Getachew et al., 2018; Shapiro et al., 2017). To meet the huge current and future demand for animal products, sustainable intensification of livestock husbandry practices is necessary. This is because the feed sub-sector is a critical component of livestock growth and transformation, as animal production is essentially a conversion of feed into an animal product, implying that the economic viability of animal agriculture is primarily determined by the quantity or quality of nutrients provided (FAO, 2018).

Because all livestock merits and mileages are directly or indirectly associated to nutrition, anything that affects the feed sub-sector will undoubtedly affect other aspects of livestock operations, such as productivity, product quality, animal health and wellbeing, farm economics, and so on (Escribano, 2018; FAO, 2012). Seasonal variability of feed resources, a scarcity of feed ingredients and high prices of feed ingredients were among Ethiopia’s significant issues in the feed business (FAO, 2018). Searching for low-cost, readily available non-conventional feeds (NCF) was viewed as an alternate measure and solution in resolving feed-related difficulties, based on this obvious reason (Seyoum et al., 2018). Ethiopia has a huge potential for non-conventional feeds available in various parts of the nation that might be harnessed and used for livestock feed (FAO, 2018).

Commelina is one of the 43 genera of Commelinaceae family, commonly called spiderwort family. With 170–215 species recorded worldwide, Commelina is considered as the largest genus of the family (Nampy et al., 2013). Members of this genus have broader distribution patterns. While some of the species adapt wide range of habitats across the world (Holm et al., 1977), like Commelina benghalensis, others have narrow range distribution or even specific habitats as Commelina albiflora Faden occurring only in Western Kenya in the East Africa (Faden, 2012). About 51 species were reported available in East Africa (Faden, 2012) out of which 17 species were confirmed in Ethiopia (Sue et al., 1997).

Commelina species contain many phytochemicals and secondary metabolites, including tannins, volatile oils, resins, flavonoids, and saponin and so on, are considered to have high therapeutic value and support ethno-uses as an antioxidant, anti-allergic, anti-inflammatory, anti-microbial, and anti-cancer agent (Jemilat et al., 2010; Sinha, 2019). Many other scholars also reported the use of Commelina as a leafy vegetable (Orech et al., 2007), fuel (Makokha et al., 2017) and as feed for cricket insects in captivity with high-quality protein (Kinyuru & Kipkoech, 2018). On the other hand, the species’ feed value has received scant attention and is not extensively documented by scientists. Numerous species of the mentioned herb were known for their feed use for many livestock species in the Konso area, southern Ethiopia. They are commonly employed by livestock keepers in the Konso community. Nonetheless, the altitudinal distribution and seasonal availability, as well as the feed usage pattern of the herb species, have not been well investigated yet. So, this study was conducted to investigate Commelina species’ feed use, emphasizing on identification, seasonal characterization, and altitudinal distribution in Konso Zone, Southern Ethiopia.

2. Materials and methods

2.1. About study area

The research was carried out in the Konso zone of Southern Ethiopia. The study site is around 595 kilometers south of Ethiopia’s capital, Addis Ababa, and 360 kilometers south of Hawassa, the capital of southern nation nationalities and people’s regional state (SNNPRS). It is situated between 5010‘0“and 5040’0“N latitude and 3700“0” and 37,045’0” E longitude (Figure 1).

Figure 1. Map of the Study Area.

The area’s elevation ranges from 501 to 2000 meters above sea level with a total land area of 2,016.24 km2 (KDAO, 2012). The zone is 70 percent low altitude and 30 percent tropical mid altitude. The zone’s average yearly temperature is 17.6–27.50 degrees Celsius and the average yearly rainfall is between 601 and 1200 millimeters (Cheung et al., 2008).

2.2. Sampling procedures and sample size

The entire sample size for this investigation was initially established using probability proportional to size-sampling (Cochran, 1977).

${\mathrm{n}}_{\mathrm{o}}=\frac{{\mathrm{z}}^2\ast (\mathrm{p})(\mathrm{q})}{{\mathrm{d}}^2}\to {\mathrm{n}}_1=\frac{\mathrm{n}\mathrm{o}}{1+\mathrm{n}\mathrm{o}/\mathrm{N}}$

Where;

n_o = desired sample size according to Cochran (1977) when population greater than 10,000

Z = standard normal deviation (1.96 for 95% confidence level)

P = 0.15 (proportion of population to be included in sample, i.e., 15%)

q = 1–0.15 i.e. (0.85).

d = is degree of accracy desired (0.05), 5% error term.

n₁ = finite population correction factor when population less than10, 000

N = is total number of populations

A multistage sampling was employed to select the respondents of this study. Out of the five districts of Konso zone, three districts, Karat zuriya district, Kena’a and Kolme, were selected randomly. Based on livestock population, availability of experimental plant, and relative economic relevance of livestock production, 15 villages (6 from mid altitude and 9 from low altitude to maintain altitudinal influence) were selected purposively, out of the 30 villages of the three districts. A list of livestock farmers was obtained from agricultural offices of each village and 13 households were selected randomly. As a result, a total of 195 households from both altitudes of the area (117 from lowlands and 78 from midlands) were chosen as interviewees for this study.

2.3. Data collection

2.3.1. Household Survey

Enumerators were hired and trained to collect household data. A structured questionnaire was used for data collection. The questionnaires were used as a guide in capturing information including data on farmers’ family sizes, education status, land and livestock holdings, seasonal availability and altitudinal distribution patterns of Commelina spp. Further information was also collected on utilization practice of Commelina spp., farmers’ perception-based livestock preferences and biomass yield ranking of the species.

2.3.2. Focus Group Discussions (FGD)

Focus group discussions (8 to 12 participants per group) were conducted at randomly selected villages at both altitudes of the study area. FGDs with key informants (3–4 elders, village leaders, and 3–4 model livestock keepers per group) were used to cross-check and authenticate individual farmers’ responses, as well as to supplement the data collected. A question checklist, driven from the basic interview questions, was used to guide the FGDs.

2.4. Plant specimen collection and identification

Commelina voucher specimens were collected from the two altitudes of the study area, numbered, pressed on thick card board paper, and thoroughly dried in the field. Field images of each mature individual plant species in their natural habitat were carefully documented during the field tour and specimen collection to aid in the identification procedure. The specimens were brought to botanical science laboratory of Arba Minch University for identification using Flora of Ethiopia and Eritrea identification guideline for Commelina (Sue et al., 1997).

2.5. Data management and statistical analysis

The data were processed, summarized, and analyzed using statistical package for social sciences (SPSS), version 20, with the Duncan multiple range test for mean separation assuming significant differences when P < 0.05. Spearman’s correlation was employed to examine the relationships between parameters. The following statistical model was used to analyze the data:

${\mathrm{Y}}_{\mathrm{i}\mathrm{j}\mathrm{k}}=\mu +{\mathrm{a}}_{\mathrm{i}}++{\mathrm{e}}_{\mathrm{i}\mathrm{j}\mathrm{k}}$

Where: Y_ijk = total observation; µ = is overall mean; α_i = altitude (low and mid); e_ijk = random error.

Ranking data were analyzed by indices computed with the principle of weighted average and indices were ranked each other using auto ranking with MS-excel 2019. The following formula was used to compute ranking index according to Musa et al. (2006).

Index = Rn*C1 + Rn-1*C2 … . + R1*Cn/∑Rn*C1+ Rn-1*C2 … . + R1*Cn;

Where, Rn= value given for the least ranked level (example if the least rank is 5th, then Rn = 5, Rn-1 = 4, R1 = 1)

Cn = Counts of the least ranked level (in the above example, the count of the 5th rank = Cn, and the count of the 1st rank = C1)

Furthermore, qualitative information obtained from exploratory study, group discussion, cross sectional survey and observations were analyzed using narrative (qualitative) analysis (Cleland, 2017), where the thoughts and arguments of the respondents were organized to give meaningful narrations about the specific points they are concerned about. Livestock numbers conversions to TLU were done based on the suggestions of Jahnke (1982)

3. Results and Discussion

3.1. Demographic characteristics of the households

3.1.1. Family size and educational level

At both altitudes of the study area, households with family size ranging from 7 to 10 (51.79%) ranked first, followed by > 10 (26.67%), 3–6 (18.46%), whereas the least were those having 3 (3.08%) members per household (Table 1). This indicates that human labor is more easily and readily available which could be a favorable opportunity for the agricultural sector in the study area. In the lowlands, families having<3 members per household (4.27%)%) were higher than their midland counterparts (1.28%). On the contrary, midland families had higher 3–6 (20.51%) and 7–10 (53.85%) members than lowlands (17.09% and 50.43% respectively) implying relatively higher family size in midlands as compared to lowlands. The report of Nigatu (2017) revealed that farmers dwelling in the midlands of Gamo zone, southern Ethiopia, had meaningfully higher family size than those in the lowlands, which coincides with the findings of the present study. In the present study, comparable percentages of the respondents attended youth education at both altitudes of the study area (11.97% in lowlands and 11.54% in midlands) whereas relatively higher percentages of respondents attended higher education in lowlands (5.98%) than those of midlands (1.28%). The illiteracy rate was also higher in midlands (43.59%) as compared to lowlands (39.32). In agreement with the present study, Nigatu (2017) reported higher illiteracy in mid altitudes (60%) of south Ethiopia relative to low altitudes (16.7%). Contrary to this, Seid (2012) reported lower illiteracy in mid altitudes (53.3%) relative to low altitudes (55 %) in Burji district, southern Ethiopia. According to Chicoine (2016), the level of literacy in a society has a positive correlation with the extent of practicing family planning and a negative correlation with family size. So, the high family size may be a reflection of the low literacy rate observed among respondents in the study area. Accessibility to schools and educational services were positively correlated to the literacy level and development of a community (Moreno-Monroy et al., 2018). So, the discrepancies in illiteracy levels in the forementioned areas could imply variability in access to education in these different areas of Ethiopia.

Table 1. Family Size and Educational Level of the respondents

Variable	Category	Altitude				Total %
		Low altitude		Mid altitude
		F	Percent	F	Percent
Family Size	<3	5	4.27	1	1.28	3.08
	3 to 6	20	17.09	16	20.51	18.46
	7 to 10	59	50.43	42	53.85	51.79
	>10	33	28.21	19	24.36	26.67
	Total (N)	117	100	78	100	100
Educational Level	Illiterate	46	39.32	34	43.59	41.03
	Youth Education	14	11.97	9	11.54	11.79
	1 to 4	27	23.08	17	21.79	22.56
	5 to 8	20	17.09	14	17.95	17.44
	9 to 12	3	2.56	3	3.85	3.08
	Higher institution	7	5.98	1	1.28	4.10
	Total (N)	117	100	78	100	100

Note: F=Frequency; N=Total sample

3.1.2. Land holding and correlation between land use patterns

According to the findings of this study, there is significant variation (P < 0.05) in total land holding among farmers under both altitudes of the study area (Table 2). Because more illiterate people may require more land for cultivation or livestock rearing. So, the lower land holding observed in mid altitudes than in low altitudes could be associated with the relatively higher illiteracy in the mid altitudes (43.04%) than in the low altitudes (38.79%) (Table 1). In Ethiopia, where farmers follow agricultural systems that necessitate larger farm sizes, farmers’ adoption of new technologies has been shown to be heavily influenced by the size of land owned by the farmers (Melesse, 2018). Accordingly, the significant variation in land holdings observed implies that technology transfer is expected to be faster and easier at low altitudes than at mid altitudes. In agreement to the current study, the findings of other scholars (Nigatu, 2017; Seid, 2012) confirmed a decreasing trend in land holdings per households with advancing altitudes.

Table 2. Land Holdings (hectare) and Land Use Pattern Correlations

	Land Holding, Altitude
	Low altitude		Mid altitude
Land Type	Mean±SD	%, Total Land	Mean±SD	%, Total Land	P-Value
Crop land	2.11±1.42^a	76.52	1.61±1.55^b	80.89	0.02
Grazing Land	0.65±0.68^a	23.48	0.38±0.63^b	19.11	0.006
Total Land	2.76±2.08^a	-	1.99±2.16^b	-	0.013
Correlation between Land use Patterns
	Crop Land		Grazing Land		Total Land
Crop Land	1.00
Grazing Land	0.945***		1.00
Total Land	0.995***		0.974***		1.00

Note: SD=Standard deviation; ^{a, b} means with the different superscripts across rows (between altitudes) are significantly different at (P<0.05)

In this study area, there was a strong positive correlation (P < 0.001) between each land use pattern (Table 2). This means that a farmer with more crop land correspondingly had more grazing land than a farmer with less crop land. Crop cultivation occupies the majority of total land (76.52 percent at low altitudes and 80.89 percent at mid altitudes). In other words, if a farmer has a larger land area, he allocates the majority of his land to food crop production and the remaining land to livestock grazing. This implies that he/she is more likely to keep a large number of livestock than a farmer with a smaller land area. In agreement with the present study, Kocho and Geta (2011) reported that, in the Wolaita and Dawuro districts of Southern Ethiopia, despite the fact that grazing land provides a significant portion of feed, particularly during cropping seasons, farmers allocate a much higher proportion of land for crop cultivation, leaving an insignificant percent of total land for livestock grazing.

3.1.3. Livestock holding in TLU

In the present study, there is a significant variation (P < 0.05) in total livestock holding among farmers in the study area’s different altitudes (Table 3). Farmers in low altitude areas have slightly more cattle, sheep, and goats (P < 0.05) than farmers at mid altitudes. According to Kocho and Geta (2011), low altitude areas have larger lands and livestock than other altitudes because they are accessible to extensive communal grazing lands that are not cultivated due to a lack of rainfall. Poultry holdings per household in the study area had a comparable distribution (P > 0.05) across both altitudes. Similarly, there is no visible variation in donkey holdings across altitudes. This suggests that the contribution of donkeys to the farmers’ economy in the study area is consistent across altitudes. The number of poultry per households in the current study is considerably higher than 0.01 ± 0.00 in the Blue Nile basin Ayele (2012). On the contrary, the same author reported number of donkeys (0.25 ± 0.02) higher than those of the current study which could be associated to the differences in importance of donkeys in the daily activities of the farmers in the areas.

Table 3. Mean livestock holding per altitude expressed in TLU

S.No.	Livestock Species	Altitude, Mean±SD		P -Value	SL
		Low altitude	Mid altitude
1	Cattle	3.77±3.45^a	2.78±2.04^b	0.023	*
2	Sheep and Goat	1.31±1.7^a	0.78±0.59^b	0.009	**
3	Donkeys	0.12±0.32	0.076±0.25	0.301	ns
4	Poultry	0.075±0.066	0.062±0.046	0.134	ns
5	Total Livestock	5.28±4.88^a	3.70±2.33^b	0.008	**

Note: TLU=Tropical Livestock Unit; SD = Standard deviation; * = means different at α = 0.05; ** = means different at α = 0.01; ns =non-significant; ^{a, b} means with the different superscripts across rows are significantly different at (p<0.05).

3.2. Identification of Commelina species available in Konso

The identification process confirmed the presence of five major Commelina species in the study area. Commelina benghalensis, Commelina imberbis, Commelina diffusa, Commelina albescens, and Commelina africana were among them. Figure 2 indicated pressed specimens and field photos of different Commelina species identified during the field study.

Figure 2. Pressed Specimen and Field Photos of Different Commelina spp.

Note: a=C.benghalensis; b=C.imberbis; c=C.diffusa; d=C.albescense; e=C.africana

3.3. Characterization of available Commelina species

3.3.1. Seasonal availability and Persistence in dry season

The availability pattern of all species is consistent across both altitudes. Except for Commelina diffusa, which was described as available year-round by the majority (89.23%) of the respondents at both altitudes, all other species were abundant with their potential vigor and biomass during and shortly after the rainy period, but showed a gradually diminishing pattern from the onset of the dry season onwards (Table 4). In agreement with this study, the reflections of other research reports (FAO, 2018; Seyoum et al., 2018) also confirmed that, fodder plants available in abundant in wet seasons but diminishes, both in quality and quantity, when advancing in to dry periods of the year.

Table 4. Availability of Commelina spp. Viewed per Season Across Altitude

Species	Availability Character	Altitude				Total
		Low altitude		Mid altitude
		F	%	F	%	F	%
C.imberbis	Available year-round	3	2.56	2	2.56	5	2.56
	Diminish slowly at dry period	104	88.89	66	84.62	170	87.18
	Diminish quickly at dry period	10	8.55	10	12.82	20	10.26
	Total (N)	117	100	78	100	195	100
C.Albescens	Available year-round	7	5.98	-	-	-	-
	Diminish slowly at dry period	85	72.65	-	-	-	-
	Diminish quickly at dry period	25	21.37	-	-	-	-
	Total (N)	117	100	-	-	-	-
C.diffusa	Available year-round	105	89.74	69	88.46	174	89.23
	Diminish slowly at dry period	10	8.55	5	6.41	15	7.69
	Diminish quickly at dry period	2	1.71	4	5.13	6	3.08
	Total (N)	117	100	78	100	195	100
C.africana	Available year-round	5	4.27	-	-	-	-
	Diminish slowly at dry period	88	75.21	-	-	-	-
	Diminish quickly at dry period	24	20.51	-	-	-	-
	Total (N)	117	100	-	-	-	-
C.benghalensis	Available year-round	6	5.13	4	5.13	10	5.13
	Diminish slowly at dry period	99	84.62	64	82.05	163	83.59
	Diminish quickly at dry period	12	10.26	10	12.82	22	11.28
	Total (N)	117	100	78	100	195	100

Note: F=Frequency; N=Total sample

Field observation and key informant discussions confirmed that, except in stony and poor soil areas, the slowly diminishing pattern in potential vigor observed with a prolonged dry season does not eventually lead to the extinction of the plant species. Instead, following an extended period of no rain, all of the Commelina spp., except C. diffusa, begins to lose their leaves gradually leaving the stems leafless or with only a few leaves at the tip of the stems. These four species will remain in this state until precipitation allows them to rejuvenate and return to their full potential vigor. This demonstrates the plant species’ strong drought tolerance, which may be associated with anatomical features such as hairy stems and leaves, deep and massive root biomass, and so on (Carvalho & Foulkes, 2018; Fort et al., 2017). Forage plants that tolerate drought and harsh environmental conditions were priority targets of feed use in animal agriculture in tropical climates. Proper and strategic use of such feed resources as supplementary feed during the dry season can help to minimize seasonal fluctuation in animal productivity (Solomon et al., 2017; Yisehak & Janssens, 2013). Consequently, the strong drought-tolerating attribute of commelina spp. could make the species a preferred supplement for dry periods and a fodder herb that should be promoted and worked with as a potential livestock fodder in rainfall limited areas like Konso of southern Ethiopia.

Despite the fact that all of the four Commelina spp. have a tendency to lose natural vigor, the nature of the reduction is not the same (Table 5). Among the four species, Commelina benghalensis was the most effective at retaining moisture after rain (Index = 0.394). This species was observed leafy in the field for a longer period of time during the dry season after all other species had shaded their leaves and were only left with their stems. This could be due to the thickest and most pubescent stem, as well as the larger fibrous root biomass nature (Figure 3). According to Carvalho and Foulkes (2018), waxy leaves and stems, which serve as means of reducing water loss through transpiration combined with deep and massive root biomass, helping to increase water uptake from the soil, aids plants with such anatomical features to withstand draught conditions.

Figure 3. Anatomical Features of C. benghalensis and C. imberbis.

Table 5. Four Commelina spp. Dry Season Persistence Potential Based Ranking for lowlands

S.NO	Species	Rank Values				Index	Rank*
		1	2	3	4
1	C.allbescens	0	3	109	5	0.201	3^rd
2	C.benghanensis	110	7	0	0	0.394	1^st
3	C.africana	0	0	5	112	0.104	4^th
4	C.imberbis	7	107	3	0	0.303	2^nd
5	Total	117	117	117	117	1

Note: *=1^st rank means most persistent to maintain its vigor in dry season followed by 2^nd and 3^rd while 4^th means least persistent

Prolific root systems are more effective than sparse root systems at scavenging and exploiting soil resources through water and nutrient uptake by nature (Carvalho & Foulkes, 2018; Fort et al., 2017). The nature of the stem is also an indicator of storing a lot more water during the rainy season and using it wisely during the dry season. The fine hairy waxes that cover the entire body of the plant, both stems and leaves, act as a wind break, keeping a humid environment around the stomata, which are located between these hairs, and thus reducing the rate of water evaporation from the leaves (Ward, 2016). As a result, these fundamental anatomical and morphological features of C.benghalensis may contribute significantly to the plant’s persistence and vigor in the dry season when compared to other species.

C. imberbis, like C. benghalensis, has a dense rooting system (Figure 3), which may explain why it ranks second in terms of drought tolerance and maintaining leafy and green vigor. C. albescens and C. africana, on the other hand, have sparsely haired or nearly hairless stems and leaves, as well as smaller root biomass. This could be a possible reason for scoring lower dry season persistence indices (Ward, 2016). as indicated in Table 5. As to the reflections of key informants and field observation reports, C. diffusa prefers river banks, water holding areas, and irrigation canals, and the likelihood of finding it far from water-rich areas is very low. Its stems can run through or on top of the water’s surface, developing roots at every node to penetrate the water and reach the ground. Therefore, it was reported to be available all year.

Although the ability varies between spp., maintaining moisture is a distinguishing innate characteristic of all Commelina spp. found in the study area. The respondents argued that, even though the leaves may become shaded as the dry season progresses, the stems generally remain green until the end of the dry season. They also pointed out that animals consuming larger biomass of commelina spp. in their daily rations during rainy seasons were observed to urinate more frequently on those days and animals fed commelina during the dry season drink less water than those fed other feed. Indicating the strong water holding capacity of the herb species. As a result, Commelina spp. were used as a major dry season feed, particularly for fattening animals and dairy cows, reducing water consumption and preventing constipation. Farmers in the study area confidently argued that if current plantation and production of Commelina increase significantly through one or more means, it will serve as a stepping stone to increase the area’s capacity to bridge the feed gap between the dry and rainy seasons.

3.3.2. Altitudinal distribution and availability of commelina species

The distribution pattern of the species, and its availability, varies across altitude (Table 6). C. imberbis, C. diffusa, and C. benghalensis were abundant at both altitudes. However, C. albescens and C. africana were sparsely distributed at the low altitudes but absent at the mid altitudes of the study area. The inconsistency observed in the distribution pattern and availability of Commelina spp. across different altitudes is an indication of the species’ altitudinal preference. In agreement with the present study, Sue et al. (1997) reported that C. albescens and C. africana grow abundantly at altitudes ranging from 300 to 1,700 masl, but it is difficult to find these species growing above 2,000 masl. Similarly, Gebrehiwot et al. (2019), stated that, altitude plays a large role in regulating availability and distribution of a given plant species (species composition). In comparison to the other three species, C. albescens and C. africana were also less common and sparsely distributed, even at low altitudes.

Table 6. Altitudinal Distribution and Availability of Commelina spp

Species	Distribution Pattern	Altitude				Total
		Low altitude		Mid altitude
		F	Percent	F	Percent	F	%
C.imberbis	Sparse	10	8.55	5	6.41	15	7.69
	Frequent	8	6.84	8	10.26	16	8.21
	Abundant	99	84.62	65	83.33	164	84.10
	Total (N)	117	100	78	100	195	100
C.Albescens	Very Sparse	6	5.13	-	-	-	-
	Sparse	105	89.74	-	-	-	-
	Frequent	6	5.13	-	-	-	-
	Total (N)	117	100	-	-	-	-
C.diffusa	Sparse	7	5.98	4	5.13	11	5.64
	Frequent	8	6.84	5	6.41	13	6.67
	Abundant	102	87.18	69	88.46	171	87.69
	Total (N)	117	100	78	100	195	100
C.africana	Very Sparse	14	11.97	-	-	-	-
	Sparse	92	78.63	-	-	-	-
	Frequent	11	9.40	-	-	-	-
	Total (N)	117	100	-	-	-	-
C.benghalensis	Sparse	7	5.98	5	6.41	12	6.15
	Frequent	12	10.26	7	8.97	19	9.74
	Abundant	98	83.76	66	84.62	164	84.10
	Total (N)	117	100	78	100	195	100

Note: F=Frequency; N=Total sample

3.3.3. Commelina species source and utilization practice

According to the reflections of the respondents of this study, C. benghalensis and C. imberbis were widely grown on terraces of farmland together with food crops. The terraces are built horizontally against the gradient of farmland. Accordingly, the Commelina spp. growing on the terraces appear as alley crops together with food crops providing many advantages for agricultural productivity, including strengthening and sustaining terraces, as well as significantly supporting soil and water conservation schemes. The species were harvested and fed to animals (cattle, goat and sheep) at home. Outdoor-reared animals were fed on species found along roadsides, riversides, and grazing areas. As a result, C. benghalensis and C. imberbis were obtained from both jungle and farmland, which were used for both grazing and the cut-and-carry system (Table 7).

Table 7. Source and Utilization Practice of Commelina Species

Species	Variable	Explanation	Altitude				Total
			Low altitude		Mid altitude		F	%
			F	%	F	%
C.imberbis	Source	Jangle only	10	8.55	13	16.67	23	11.79
		Jangle and Farmland	107	91.45	65	83.33	172	88.21
		Total (N)	117	100	78	100	195	100
	Utilize	Cut and carry only	0	0	0	0	0	0
		Grazing only	0	0	0	0	0	0
		Grazing, cut and carry	117	100	78	100	195	100
		Total (N)	117	100	78	100	195	100
C.Albescens	Source	Jangle only	117	100	-	-	-	-
		Jangle and farmland	0	0.00	-	-	-	-
		Total (N)	117	100	-	-	-	-
	Utilize	Cut and carry only	0	0	-	-	-	-
		Grazing only	0	0	-	-	-	-
		Grazing, cut and carry	117	100	-	-	-	-
		Total (N)	117	100	-	-	-	-
C.diffusa	Source	Jangle only	117	100	78	100	195	100
		Jangle and farmland	0	0.00	0	0.00	0	0
		Total (N)	117	59.49	78	100	195	100
	Utilize	Cut and carry only	0	0	0	0	0	0
		Grazing only	0	0	0	0	0	0
		Grazing, cut and carry	117	100	78	100	195	100
		Total (N)	117	100	78	100	195	100
C.africana	Source	Jangle only	117	100	-	-	-	-
		Jangle and farmland	0	0.00	-	-	-	-
		Total (N)	117	100	-	-	-	-
	Utilize	Cut and carry only	0	0	-	-	-	-
		Grazing only	0	0	-	-	-	-
		Grazing, cut and carry	117	100	-	-	-	-
		Total(N)	117	100	-	-	-	-
C.benghalensis	Source	Jangle only	18	15.38	3	3.85	21	10.77
		Jangle and farmland	99	84.62	75	96.15	174	89.23
		Total (N)	117	59.49	78	40.51	195	100
	Utilize	Cut and carry only	0	0	0	0	0	0
		Grazing only	0	0	0	0	0	0
		Grazing, cut and carry	117	100	78	100	195	100
		Total (N)	117	100	78	100	195	100

Note: F=Frequency; N=Total sample

C. africana, C. diffusa, and C. albescens, on the other hand, were considered invasive weeds on farmlands and were not left on terraces, despite the fact that they were equally used as feed as the other two species. Farmers take the species from their natural habitat and feed them to their animals indoors, while grazing animals consume them on grazing land. Grazing and cut and carry systems were the very common method of feed resource utilization practiced by livestock keepers at different parts of Ethiopia (Gebremariam & Belay, 2016; Hassen et al., 2010).

3.3.4. Pattern of livestock species preference in feeding commelina spp

Livestock species preference in feeding commelina spp. was depicted in Figure 4. The species preference response reveals a consistent pattern for all Commelina species and no preference difference was observed across both of the altitudes of the study area. Majority of the households indicated that there was no preference difference between livestock species in feeding all of the Commelina spp. available in the study area. That is, all livestock species reared by farmers in Konso, including cattle, sheep, goats, donkeys, and poultry, feed on commelina with no discernible preference for different Commlina spp. available in their vicinity. This demonstrates the potential opportunity of the plant species, inviting extensive research to be conducted on them.

Figure 4. Pattern of Livestock Species Preference in Feeding Commelina spp.

3.3.5. Biomass yield potential based ranking of commelina species

The biomass yield data per species indicate that C. benghalensis was reported as the most biomass yielding species of all (Index = 0.326), followed by C. imberbis, C. diffusa, C. africana and C. albescens in their decreasing order of yielding potential (Table 8). In this study, biomass yield-based ranking appears to be related to the species’ tillering potential. Meng et al. (2018) confirmed strong positive linear relationships between biomass and surface area of fine roots and aboveground production in their correlation study. Similarly, Tian et al. (2017) found that having more tillers per plant per unit area results in greater leaf biomass, increased photosynthesizing potential, and thus a larger fraction of total aboveground biomass.

Table 8. Biomass yield based ranking of Commelina spp. for lowlands

S.NO	Species	Rank Values					Index	Rank*
		1	2	3	4	5
1	C. diffusa	0	9	102	6	0	0.202	3^rd
2	C. benghanensis	105	12	0	0	0	0.326	1^st
3	C. allbescens	0	0	0	8	109	0.071	5^th
4	C. imberbis	12	96	9	0	0	0.268	2^nd
5	C. Africana	0	0	6	103	8	0.132	4^th
6	Total	117	117	117	117	117	1

Note: *=1^st rank means most biomass yielder followed by 2^nd and 3^rd while 4^th means least biomass yielder of all

3.3.6. Supplement value

As to the reflections of the interview and FGD participants of this study, Commelina spp. were effective and productive supplementary feeds, not less than conventional improved forage crops. As per their comments, Commelina species were supplemented to growing animals with severely retarded or stunted growth to stimulate compensatory growth. Farmers crush the leaves of Commelina with a mortar and pestle and feed it to calves that are not yet mature enough to feed on coarse feed. They believe that Commelina greatly accelerates the growth rate of young animals. Farmers provide the plant species as a milk replacer for nearly-weaned calves in order to maintain the calves’ normal growth rate. Respondents in this study strongly believe that Commelina spp. help newly calved cows maintain their bodies quickly. Because of this, Commelina spp. was among the first and foremost supplements given to recently delivered cows, prior to any other feed. The farmers also added that Commelina spp. supplements are highly recommended and preferred by newly calved cows, just like porridge is for a mother after her delivery. To that end, farmers who grow Commelina spp. in their gardens or farms primarily supplement them for their cows. However, if he/she does not have Commelina on his/her farmland, he/she must borrow Commelina from a neighbor/relative. In that case, none of the farmers react negatively when his neighbor comes to borrow Commelina for his/her recently delivered cow. Hence, Commelina spp. serves as a tool to strengthen social integration among livestock keeping communities, extending the role of Commelina beyond feed value.

Provided that transmission of knowledge continues among generations, the long history of observations retained by indigenous people can provide important baseline information for the basic science (Jessen et al., 2022). And, insights from indigenous knowledge were potentially helpful in research process, including but not restricted to, project conceptualization and hypothesis setting. Atleo (2011), also noted that, indigenous knowledge was a cumulative output long years hypothesis formulating and testing regular practice by indigenous people. So, it follows that, the supplement value of Commelina spp. elaborated by the respondents of this study could serve as a potential clue about the actual supplement use of the herb species that could be tested by further in vivo and in vitro investigations on it.

4. Conclusions

Five main Commelina spp., viz., Commelina benghalensis, Commelina imberbis, Commelina diffusa, Commelina albescens, and Commelina Africana, were confirmed to be present in the study area. While C. diffusa was available all year, all other species showed a gradually diminishing pattern from the start of the dry season onwards. C. imberbis, C. diffusa, and C. bengalensis were well adapted to thrive at both altitudes. However, C. albescens and C. Africana were sparsely distributed at low altitudes and were not potentially growing at mid altitudes. The plants are consumed by all livestock species, with no preference for one Commlina species over another. C.benghalensis was deemed as the most biomass yielding species due to its high tillering and leaf bearing rates. Commelina spp. have been used as a nutritious and productive supplementary feed for young starter calves, as a milk replacer for weaned calves, and as a body strengthening and tissue maintenance supplement for nearly calved cows.

C. benghalensis and C. imberbis were grown as alley crops on arable land along with food crops. The tendency of these two Commelina spp. to grow sociably as alley crops, combined with a wider and analogous usage pattern across various corners of the study area, suggests that their worth may extend beyond feed usage. As a result, more research on the species’ numerous benefits as: ecological impacts of Commelina spp.; their role in maintaining and sustaining soil and water conservation schemes, biological compatibility of Commelina spp. when intercropped with food crops, is required. Even though all of the farmers in the study area were aware of the feed worth of commelina spp., in a few areas, the habit of cultivating C. benghalensis and C. imberbis as alley intercrops on farmland was not consistently practiced across all the corners of the study area. So, agricultural experts must transfer intercropping skills to farmers who lack them. Nutritional quality of the herb species should also be conducted to have a clear picture about the feed value of the plant species.

Consent to participate

Informal verbal consent was obtained from all of the participants included in interview and FGD

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

The data that support the findings of this study are available from the corresponding author on reasonable request.

Additional information

Funding

The authors received no direct funding for this research.

Notes on contributors

Kebede Gelgelo

Kebede Gelgelo is a Senior Lecturer and researcher at Arba Minch University, Department of Animal sciences. He has special interests for working with non-conventional feed resources.

Yisehak Kechero

Professor Yisehak Kechero was a professor of animal nutrition and feeding in Arba Minch University, Department of Animal sciences. He has widely published in the areas of animal feeding.

Dereje Andualem

Dereje Andualem was a lecturer and researcher at Dilla University, Department of Animal and range sciences