Livestock Research for Rural Development 27 (10) 2015 Guide for preparation of papers LRRD Newsletter

Citation of this paper

Assessment of phenotypic traits relevant for adaptation to hot environments in indigenous chickens from four agro-climatic zones of Kenya

G K Moraa, P A Oyier1, S G Maina1, M Makanda, E K Ndiema2, A E Alakonya, K J Ngeiywa3, J Lichoti3 and S C Ommeh

Institute for Biotechnology Research, Jomo Kenyatta University of Agriculture and Technology, P.O Box 6200-00200, Nairobi Kenya
sommeh@jkuat.ac.ke
1 Department of Information Technology, Jomo Kenyatta University of Agriculture and Technology, Kenya
2 Department of Earth Sciences, National Museums of Kenya
3 Department of Veterinary Services, State Department of livestock, Ministry of Agriculture Livestock and Fisheries, Kenya

Abstract

Indigenous chickens are robust in adapting to their environments. However, global warming due to the ongoing climate change especially in the horn of Africa has made indigenous chickens vulnerable to conditions such as heat stress. We conducted a study on 296 indigenous chickens from four agro-climatic zones of Kenya: Lamu archipelago, Mt. Elgon catchment, Lake Victoria basin and Lake Turkana basin. We report significant interactions between comb types in response to outside temperature in the various agro climatic zones. Plumage density was significant to the body temperature of indigenous chickens. However, we did not see any significant relationship between the crested and feathered shank phenotype, morphological traits such as skin colour, comb colours, earlobe colours, shank colours and wattle colour to the outside temperature. The outside temperatures in the various agro climatic zones were not similar.

We characterized indigenous chickens based on their phenotypic, morphological and physiological traits relevant for adaptation to hot environment. We analysed our data using R Core statistics package version 3.1.2 and Microsoft excel spread sheet. Our results indicate that chickens from Lamu archipelago and Lake Turkana basin have various comb types unlike the other regions. Overall yellow was the predominant shank colour while white was the predominant earlobe colour followed closely by yellow. All chickens from Mt. Elgon catchment had dense plumage while chickens from the other zones had normal plumage. We also sampled various phenotypes in the four zones. In Lamu archipelago Kuchi phenotype was predominant while bantam phenotype was only common to Lake Turkana basin.

Generally, this study has revealed that some traits could be of importance for adaptation of indigenous chickens to hot environments. Further studies should be carried out to characterize these traits in indigenous chickens found in other arid and semi-arid regions of Kenya. This will improve efforts to promote their conservation and improvement through sustainable use.

Key words: climate change, diversity, heat stress, horn of Africa, poultry


Introduction

Poultry farming in Kenya is identified as one of the lead livestock enterprises and it’s also fast growing (Nyaga 2007). Out of the 31.8 million domesticated birds in Kenya, 70% comprise indigenous chickens (25,756,487) whereas commercial chickens are 6,071,042 (KBS 2009). Indigenous chickens are mostly found in the rural areas and are good scavengers, have good maternal qualities, have high survival rates and are hardier compared to the exotic breeds (Kingori et al 2010). They are raised under extensive free systems (Sonaiya 1990; Kitalyi 1998). This system exposes them to harsh conditions such as extreme weather changes being experienced in the horn of Africa often leading to decreased productivity (Okeno et al 2012).

Chicken suffer high temperature because the feather coverage hinders internal heat dissipation. Decreased feather coverage provides relative heat tolerance (Yalcin et al 1997). Exposure of chickens to high temperature results in changes at the metabolic, physiological and cellular levels. This in turn leads to decrease in feed consumption and chicken weight consequently leading to low efficiency and productivity in hot climates (Coble et al 2013; Etches et al 2008). This is a challenge especially to chickens found in hot environments. Several studies have been done on various chicken phenotypes to assess their performance in hot environments. A study conducted by Cahaner et al (2008) indicated that the naked neck gene can be used to alleviate heat stress. Interestingly, the naked neck genotype has been shown to affect heat dissipation traits like the wattle length, rectal and surface temperature measurements (Chen et al 2008).

The frizzled genotype has also been studied in chickens exposed to high ambient temperatures. This gene has beneficial effects in decreasing heat stress in poultry production (Zerjal et al 2013). In addition to the naked neck and the frizzled gene, the dwarf gene has been shown to have no value with regard to chicken tolerance to chronic heat stress (Deeb and Cahaner 2001). Other than the phenotypes, some studies have also been conducted on some morphological traits of indigenous chickens. Studies by Duguma (2006; 2009) characterized some indigenous chicken ecotypes of Ethiopia. These studies looked at some morphological traits such as plumage colour, earlobe colour, comb colour, skin colour among other traits in various indigenous chicken ecotypes in Ethiopia. These studies indicated that chickens found in the highland areas of Ethiopia differed from those found in the lowlands. Guni and Katule (2013) characterised some indigenous chickens in selected southern highlands of Tanzania. This study looked at some morphological traits and it revealed that frequencies of various plumage forms and colours vary from one location to another. We therefore aimed to describe the phenotypic traits in indigenous chickens found in hot environments in Kenya.


Materials and methods

Study area

This study was conducted in Lake Turkana basin, Lamu archipelago, Lake Victoria basin and Mt. Elgon catchment. These were the preferred areas since Mt. Elgon catchment and Lake Turkana basin experience extreme climatic conditions whereas Lake Victoria basin and Lamu archipelago experience intermediate weather conditions. Besides, some of these areas were not adversely affected by the cockerel and pullet exchange programme. Mt. Elgon is located at an altitude of 3000m above sea level. It is positioned between 0°27'38.76' South latitude and 34°6'41.26' East longitude. It is also found in zone I and II of the agro-climatic zones of Kenya. These two zones are considered wet and they are characterized by an annual rainfall of 1000mm per annum and an annual temperature of 0°C minimum and 22.0°C maximum. Some of the areas are moorland areas and communities have been found to keep livestock including indigenous chickens. Lake Victoria basin lies in zone III and receives an annual rainfall of 500-1000 mm with an annual temperature of 17.1°C minimum and to 29.4°C maximum. It is situated between 0°24'41.74' South latitude and 34°9'51.55' East longitude. Lamu is located between 2°16'10.41' South latitude and 40°54'2.31' East longitude. It lies within zones IV of the agro-climatic zones, this zone is considered dry and humid and receives an annual rainfall of 800mm and an annual temperature of 24.1°C minimum and 29.2°C maximum. Turkana basin is positioned between 3°37'36.55' South latitude and 36°0'8.35' East longitude. It lies within zone VI and zone VII of the agro- climatic zones of Kenya. These zones are characterized by annual rainfall of 200-600 mm which is quite unreliable since crops and livestock can hardly survive in this environment. It’s also characterized by an annual temperature of 23.7°C minimum and 42°C maximum. These zones are considered as deserts and they are the driest part of Kenya.

Figure 1. Map of study Area source; (www.infonet-biovision.org)

Table 1. Summary of sampled locations

Agro climatic zone

Population

Number of samples

Lake Turkana basin

Lake Turkana East

33

Lake Turkana West

61

Total

94

Lamu Archipelago

Lamu North

27

Lamu central

30

Lamu South

46

Total

103

Lake Victoria Basin

Homabay

24

Total

24

Mt. Elgon catchment

Mt.Elgon north

31

Mt. Elgon south

44

Total

75

Total samples

296


Data collection

We conducted field surveys in remote villages that were not affected by the cockerel and pullet exchange programme in the four agro-climatic zones. We conducted Interviews at the farmers’ houses with the assistance of local agricultural extension officers. We used a pre-tested questionnaire on open data kit (ODK) on phones to obtain the morphological and physiological data of the indigenous chickens based on adaptation to hot environments. We characterised a total of 296 genetically unrelated adult indigenous chickens from 10 populations each having 20-30 individuals. Some of the phenotypic attributes we studied include; skin colour, shank colour, comb type, comb colour, earlobe colour, wattle colour, presence of a crest and presence of feathers in the shank and plumage density. Plumage density was characterised as dense (presence of feathers under the wings, on the thighs, shanks and in the breast bone); normal plumage chickens had average feathers on their bodies while in scarce plumage chickens had very few feather coverage on their bodies. We also took measurements of the body temperature as a physiological trait, outside temperature and global positioning system (GPS).

Data Analysis

We analysed our data using Excel spread sheet software package 2013 to compute frequencies of occurrence of each trait. We also used ANOVA tests in R core statistics software version 3.1.2 to determine relationships between various traits and the ecosystems in response to outside temperature. We used a box plot in R to show if any relationship exists between the outside temperature and the various agro climatic zones. To determine the relationship between outside temperature and body temperature in the various agro-climatic zones we used a conditioning plot.


Results and Discussion

Table 2. Distribution (%) of various phenotypes in the agro climatic zones of Kenya

Phenotypes

Agro climatic zones

Lamu archipelago
(n=103)

%

Lake Turkana basin
(n=94)

%

Lake Victoria basin
(n=24)

%

Mt. Elgon catchment
(n=75)

%

Total

%

Frizzled

2.00

50.0

0.00

0.00

0.00

0.00

2.00

50.0

4.00

0.84

Bantam

0.00

0.00

39.0

100

0.00

0.00

0.00

0.00

39.0

8.21

Rumpless

0.00

0.00

0.00

0.00

0.00

0.00

1.00

100

1.00

0.21

Kuchi

103

100

0.00

0.00

0.00

0.00

0.00

0.00

103

21.7

Mixed

59.0

26.3

83.0

37.1

18.0

0.08

64.0

0.28

224

47.2

Naked neck

2.00

0.13

5.00

0.33

3.00

0.20

5.00

0.33

15.0

3.16

Plain feathered

8.00

0.40

9.00

0.45

0.00

0.00

3.00

0.15

20.0

4.21

Crested

0.00

0.00

6.00

0.27

1.00

0.05

15.0

0.68

22.0

4.63

Mottled

0.00

0.00

7.00

0.58

3.00

0.25

2.00

0.17

12.0

2.53

Barred Feathers

1.00

0.05

3.00

0.14

6.00

0.29

11.0

0.52

21.0

4.42

Feathered shanks

0.00

0.00

1.00

0.07

0.00

0.00

13.0

0.93

14.0

2.95


Table 3. Proportionate (%) occurrence of morphological traits of indigenous chickens in various agro-climatic zones

Agro-climatic zones

Character

Expression

Mt.Elgon catchment
(n=75)

Lake
Victoria basin
(n=24)

Lake
Turkana basin
(n=94)

Lamu Archipelago
(n=103)

Comb type

Single

Walnut

Cushion

Pea

Rose

Strawberry

96.0%

0.00%

0.00%

0.00%

0.00%

1.33%

95.8%

0.00%

0.00%

0.00%

0.00%

4.17%

84.0%

0.00%

1.06%

0.00%

11.7%

3.19%

3.88%

7.77%

0.97%

12.6%

5.83%

68.9%

Comb colour

Red

Pale

Black

90.6%

9.33%

0.00%

70.8%

29.1%

0.00%

85.1%

13.8%

1.06%

48.5%

51.5%

0.00%

Earlobe colour

Red

Yellow

Black

White

21.3%

32.0%

1.33%

45.3%

45.8%

45.8%

0.00%

8.33%

11.7%

5.32%

2.13%

80.8%

22.3%

5.83%

0.00%

71.8%

Wattle colour

Red

Pale

Black

89.3%

9.33%

1.33%

70.8%

29.2%

0.00%

85.1%

14.8%

0.00%

48.5%

51.4%

0.00%

Skin colour

White

Yellow

Cream

Grey

61.3%

36.0%

1.33%

1.33%

29.2%

70.8%

0.00%

0.00%

90.4%

8.50%

1.10%

0.00%

96.1%

3.90%

0.00%

0.00%

Shank colour

White

Yellow

Grey

Black

Green

Cream

33.3%

52.0%

8.00%

4.00%

2.67%

0.00%

25.0%

70.8%

4.16%

0.00%

0.00%

0.00%

68.1%

20.2%

6.38%

4.26%

0.00%

1.06%

43.7%

54.4%

0.00%

1.94%

0.00%

0.97%

Plumage density

Dense

Normal

Scarce

82.7%

17.3%

0.00%

0.00%

100%

0.00%

0.00%

100%

0.00%

0.00%

98.1%

1.94%

Comb type and comb colour

We observed different comb types (single, strawberry, rose, walnut, cushion, pea, and buttercup) in the four agro-climatic zones. Out of the total proportion studied, single comb was predominant in Mt. Elgon catchment, Lake Victoria basin and Lake Turkana basin. Interestingly, strawberry comb was predominant in Lamu archipelago. Additionally, all comb types were observed in this region. Mt Elgon catchment and Lake Victoria basin had only single and strawberry comb types. Lake Turkana basin had single, cushion rose and strawberry combs. These results have indicated that various comb types exist in various regions and in various chicken phenotypes. Msoffe et al (2001) also indicated that certain comb types occur more frequently in some chicken ecotypes than in others. Other research findings (Apuno et al 2011; Guni and Katule 2013; El-Safty 2012) reported the predominant occurrence of single comb type in indigenous chicken populations. The appearance of various comb types could be due to adaptation to suit into various agro climatic zones which might be brought about by gene mutations.

We observed three comb colours: red, pale and black. Red combs were predominant in Mt. Elgon catchment, Lake Victoria basin and Lake Turkana basin. However, pale colour was common in Lamu archipelago. This report reflects what was reported by Guni and Katule (2013) that Red and pale colours were common in Tanzanian chicken ecotypes, and Faruque et al (2010) whose study showed the occurrence of red combs in Bangladesh chickens.

Ear lobe colour and Wattle colour

We observed red, white, yellow and black earlobes. White was the predominant earlobe colour. This was followed by yellow and red earlobes. Theses colours varied across all the agro climatic zones. We also observed low frequencies of black earlobes in Mt. Elgon catchment and Lake Turkana basin. The results of this study are similar to those reported by (Egahi et al 2010; Guni and Katule 2013; Iqbal and Pampori 2008). These studies reported differences in earlobe colours among indigenous chickens. Variations in earlobe colours have been thought to be of genetic origin since earlobe colour is dependent upon several genetic factors (Guni and Katule 2013).

We observed three wattle colours; red, pale and black. Red wattles were common in Mt. Elgon catchment, Lake Victoria and Lake Turkana basins. Interestingly, most of the chickens in Lamu archipelago had pale earlobes. Pale wattles were also observed in the other agro climatic zones. In addition to red and pale colours, we also observed black wattles in Mt Elgon catchment but in very low frequencies. These results are similar to reports by (Kingori et al 2010) on wattle colours in indigenous chickens.

Skin colour and shank colour

We observed differences in skin colour across the four agro climatic zones that were white, yellow, cream and grey skin colours. White was the predominant skin colour in Lamu archipelago, Mt. Elgon catchment and Lake Turkana basin. Interestingly in Lake Victoria basin, yellow was the predominant skin colour. All colours were observed in Mt. Elgon catchment. These results are similar to those reported by (Guni and Katule 2013; Kingori et al 2010; Msoffe et al 2001). However these results contrast with those from Dana et al (2010) who reported yellow skin to be the most predominant skin colour in Ethiopian chickens.

We observed different shank colours (white, yellow, cream, black, grey and green) across the four agro climatic zones. Overall yellow shanks were most common across the agro climatic zones. These results are similar to reports by Cabarles et al (2012),  Guni and Katule (2013) and Msoffe et al (2001). Conversely, these results differ from those observed by Egahi et al (2010) and El-Safty (2012) who reported black as the predominant skin colour. This was followed closely by white shanks. We only observed green shanks in Mt. Elgon catchments though in low frequencies. We didn’t observe any black shanks in Lake Turkana basin. Lamu archipelago was the only regions where we didn’t observe grey shanks. Cream shanks were common in Lake Turkana basin and Lamu archipelago though in small frequencies. These results have shown variation in shank colours across the various agro climatic zones and this is in agreement with a research conducted by Msoffe et al (2001).

Plumage density

We observed normal plumage densities across the three agro climatic zones except Mt. Elgon catchment. All chickens from Mt. Elgon catchment which experiences cold climate had dense plumage. This could be an adaptation to enable them conserve enough heat since feather coverage hinders heat loss (Yalcin et al 1997).

Table 4. ANOVA results of relationship between various traits in response to the outside temperature

Trait response to outside temperature

p

Comb type

0.05

Comb colour

1.0

Earlobe colour

1.0

Wattle colour

1.0

Skin colour

0.10

Shank colour

1.0

Plumage density

0.001

Phenotype crested

0.10

phenotype feathered shank

0.66

Agro-climatic zones

0.001

Relationship between various traits, in response to the outside temperature

In general this study has shown significant interaction between comb types, and plumage density to the outside temperature in the various agro climatic zones. Overall, single comb was predominant in all zones. However, Lake Turkana basin and Lamu archipelago had varied comb types. Dense plumage was only specific to Mt. Elgon catchment while the other regions had normal plumage. There was also a significant relationship between the various agro climatic zones to the outside temperature.

This study did not show significant interaction between the comb, earlobe, wattle, skin and shank colours to the outside temperature. It is also worth noting that this study did not show any significance between the crested and feathered shank phenotype to the outside temperature. This could be attributed to the low frequencies of these phenotypes observed during sampling.

Relationship between agro-climatic zones and various traits, in response to the outside temperature

Table 5. ANOVA results of analysis of ecosystem, and various traits in response to the outside temperature

Trait response to outside temperature

p

Agro-climatic zones and comb colour

0.10

Agro-climatic zones and comb type

0.10

Agro-climatic zones and earlobe colour

0.10

Agro-climatic zones and wattle colour

1.00

Agro-climatic zones and shank colour

1.00

Agro-climatic zones and skin colour

1.00

Agro-climatic zone and plumage density

0.05

Agro-climatic zone and phenotype crested

0.80

Agro-climatic zone and phenotype feathered shank

0.90

This study also tried to find out whether there is any significant interaction between the agro climatic zones and various traits in response to outside temperature. We found out that there is a significant relationship between the agro climatic zones and plumage density to the outside temperature. However, we did not see any significant relationship between the agro climatic zones and comb colour, comb type, earlobe colour, wattle colour, shank colour and skin colour to the outside temperature. Also, no significance was observed between the agro climatic zones, crested and feathered shank phenotypes in response to the outside temperature.

Figure 2. Box plot showing the relationship between outside temperature and various agro climatic zones

To determine whether outside temperature across the four agro climatic zones was uniform, we obtained a box plot using R core statistical package. This indicated that outside temperature was not uniform across the four agro climatic zones. Lake Turkana basin recorded the highest temperatures and this was followed by Lamu archipelago then Lake Victoria basin. Mt. Elgon catchment recorded the least temperature. This is in line with the works of Jaetzold and Schmidt (1983) and Paron et al (2013) about outside temperatures in these regions.

Figure 3.  A conditioning plot illustrating the relationship between body temperature and outside temperature

We also drew a conditioning plot of body temperature against outside temperature in the four agro climatic zones. We found out that chickens in Lake Turkana basin had very high temperatures followed by chickens from Lamu archipelago. Lake Turkana basin and Lamu archipelago are characterised by high temperatures since they are arid and semi-arid lands respectively. Chickens from Mt. Elgon catchment had the least temperatures. This could be due to the cold climate experienced in this region.


Conclusions


Recommendations


Acknowledgment

The authors wish to thank the Department of Veterinary Services under the Ministry of Agriculture Livestock and Fisheries for supporting this research. Appreciation is also extended to the extension officers and the farmers for their co-operation during data collection.This research was funded through a research grant JKU/2/4/RP/181 awarded to Dr. Sheila Ommeh by Jomo Kenyatta University of Agriculture and Technology.


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Received 1 July 2015; Accepted 23 August 2015; Published 1 October 2015

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