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Citation of this paper

Growth performance of Sudan Baggara bulls fed diets containing Hibiscus (Karkade) seeds as a non-conventional protein source

G M Suliman, S A Babiker* and H M Eichinger**

Department of Meat Production, Faculty of Animal Production, University of Khartoum, Sudan
* Institute for Promotion of Livestock Export, University of Khartoum, Sudan.
** Main Laboratory for Biochemical Analysis (HVA), Technical University of Munich, Germany
gm_suliman@yahoo.com

Abstract

Fifty-five bulls of Sudanese Baggara cattle type were used for this study. Bulls were divided into five treatment groups each of eleven animals. Five iso-caloric, iso-nitrogenous diets 0HS, 25HS, 50HS, 75HS and 100HS were formulated to contain different levels of Karkade seeds protein to replace 0%, 25%, 50%, 75% and 100%  of groundnut cake protein. The diets were randomly distributed among the animal groups. The feeding trial extended for eighty-four days starting with an adaptation period that lasted in two weeks.

 

No significant differences were observed between the treatment groups in slaughter data. Although, animals of group 0HS showed the best results in slaughter weight, empty body mass, hot carcass weight and chiller shrinkage, but not for dressing percentage where animals of group 75HS attained the highest value. Weight of loin joint was significantly (P<0.05) different between group 25HS and 75HS, and group 50HS and 75HS, where the later group showed the highest weight. Muscle, bone, fat and trimmings weights were not significantly different between the treatments; while muscle-to-bone ratio was the highest in group 0HS and the least in group 50HS. Conversely, group 100HS showed the highest muscle-to-fat ratio and group 0HS attained the least ratio. The difference was only significant (P<0.05) between group 0HS, 25HS and 100HS. no significant differences were observed in body components between the treatment groups, except for hide weight, mesentery and omental fat.

 

It is concluded that general growth performance of the experimental groups was improved as inclusion level of Karkade seeds increased up to 75%. Meat quality attributes were also enhanced with inclusion of Karkade seeds protein.

Keywords: Baggara, growth, Karkade, protein


Introduction

Roselle (Hibiscus sabdariffa L.) is given many names at different parts of the world; Rozelle, Sorrel, Sour-Sour, Jelly Okra, Oseille de Guinee, Sereni and other names. This indicates it’s widespread over variety of lands under variable growing conditions. Roselle (Hibiscus sabdariffa) is a highly important cultivated medicinal and beverage crop grown in Sudan.  Roselle in Sudan is named Karkade. It is cultivated extensively in the rainfed sandy dunes of Western region of the country. The type of roselle produced in the country belongs to the botanical variety sabdariffa. It is believed to have originated in West Africa and from there it has been introduced to western Sudan. Several local strains can be identified on the basis of calyx shape and color and other plant characteristics. Sudan is the most important Karkade producer in Africa with annual area fluctuating between 11,000 ha and 57,000 ha depending on the amount of rainfall and prices. Smallholder farmers traditionally grow Karkade in plots ranging from under 0.25 to 2 ha, but some growers have areas of up to 20 ha. Recent collection missions in Sudan have resulted in the collection of 88 accessions with different plant and calyx characters, HCENR (2006). Its production in the irrigated clays is limited and can only be found scattered in the northern region and recently in the center.

 

Karkade requires a permeable soil, a friable deep, fertile sandy loam being preferable; however, it is well adapted to a variety of soils. It must be kept weed-free. It tolerates flood, heavy winds and stagnant water. Karkade is reported to resist annual temperature of 12.5 C to 27.5 C and pH of 4.5 to 8.0 (Duke 1978, 1979). Soil is prepared deeply to about 20 cm. Depending on the soil; seeds are sown at the rate of 11-22 kg/ha. Weeding for first month is important, but after the plant reaches (45-60 cm) in height, weeds will be no longer a problem. Fertilization practices vary widely. Karkade responds favorably to applications of nitrogen. Rotation is sometimes used to break the life cycle of its root-knot nematode, Heterodera radicicola. Seedlings may be raised in nursery beds, then transplanted when (7.5-10 cm) high, but seeds are usually set directly in the field. When 2 or 3 leaves have developed, the seedlings are thinned out by 50%. No early thinning is made, if the plant is grown mainly for herbage. The fruits are harvested when completely grown but still tender and at this stage are easily broken off by hand. If harvesting is delayed and the stems have toughened, clippers must be used. The fruits of Karkade ripen progressively from the lowest to the highest. Harvesting of seeds takes place when the lower parts of the fruits are mature, then the plants are cut down, piled for a few days then threshed. The intensity of the calyx color of local cultivars, include green, light red, light red with white stripes, dark red and deep dark red. These varieties produce an orange-red colored liquid with a slightly less tart but more acidic taste that believed to be good for herbal tea base.

 

The total cultivated area of Karkade in Sudan is estimated to be 36.4 ha; producing 24,000 metric tones at a rate of 914 kg/ha (CBOS 2007). Most of these quantities are exported to different destinations around the world or consumed locally as a drink. The process of Karkade production leaves large quantities of calyces and seeds without any further utilization. Some Sudanese animal-herd owners are noticed to use these seeds in diets for their animals.

 

Chemically Karkade seeds were found to contain 94.2% DM, 19.9% EE, 28% CP, 5.5% ash, 18% CF and 23% NFE (APRC 1999), but other studies estimated crude protein to be 20 -21.4 % (Rao 1996; AFRIS 2004 and Tomas-Jinez et al 1998), 24 – 25.2 % (Duke 1983; Al-Wandawi et al 1984), 27 – 27.8 % (Ahmed and Hudson 1982) and 30 – 33.4 % (El-Adawy and Khalil 1994 and Bakheit 1989). The seed oil is reported to be rich in oleic and linoleic acids (Salama 1979, Ahmed and Hudson 1982, and Ahmed and Nour 1993).

 

Pond et al (1995) considered Karkade as one of the new multiple-use species that need to be well identified and exploited. One of these attempts is the use of Karkade seeds as a food ingredient in diets for feeding animals. However, several important factors are involved in determining the acceptability of a given food ingredient for inclusion in the diet of a particular animal specie. These include: cost, palatability, digestibility, nutrient content and balance, presence of toxins or nutrient inhibitors and not being consumed by humans. The cost of seeds in Sudan is nearly zero, thus the use of these seeds in diets for feeding ruminant is promising.

 

In addition to reduction of animal production cost, a positive contribution to the pollution problem could be made. However, limited information is available as regard the nutritive value of Roselle seeds in diets for growing and fattening animals. Such information forms a base to any further studies concerning use of this non-conventional feed source in animal feed.

 

The objective of this study is to evaluate Karkade seeds as a non-conventional source of protein and its effects on growth performance of beef cattle.

 

Material and methods 

Experimental animals

 

Fifty-five Sudan Baggara bulls (Bos indicus) were used for the study. Their average weight was 213 kg 2.09 kg, while their age was around 18 months. These animals were housed in a bamboo-shaded pen divided equally into five subunits of 20 m2 each. Each unit was provided with feeding and watering facilities. The animals were then weighed, ear-tagged and left for an adaptation period of two weeks. During this period, bulls were vaccinated against the main local epidemic diseases in the region and fed a mixture of the experimental diets.

 

At the end of the adaptation period, the animals were weighed after an overnight fast except for water. Accordingly, they were randomly redistributed into five feeding groups of similar live weight and number.

 

Feeds and feeding

 

Sorghum grains, groundnut cake, Karkade seeds, molasses, urea, wheat bran, groundnut hulls, common salt and limestone powder constituted the experimental diets ingredients. Table 1 represents the chemical composition of Karkade seeds and groundnut cake.


Table 1.  Chemical composition of Karkade seeds and groundnut cake (air dried)

Composition, g kg -1

Karkade seeds

Groundnut cake

DM

951

954

Oil g

162.4

79.6

CP

288.2

435.8

Fiber

151.3

97.2

Ash g

44.3

92.5

NFE

304.8

248.9

Source: APRC 1999


Groundnut cake was the source of protein in the control diet. In the other diets, Karkade seeds protein replaced groundnut protein at the rate of: 25%, 50%, 75% and 100%. According to chemical analysis of groundnut cake and hibiscus seeds, the levels of groundnut hulls and molasses were manipulated to make experimental diets iso-caloric and iso-nitrogenous (Table 2).  


Table 2.  Ingredients proportions of the experimental diets

Ingredients, %

Experimental diets

0HS

25HS

50HS

75HS

100HS

Groundnut cake

20

15

10

5

0

Karkade seeds

0

7.5

15.1

22.6

30.2

Sorghum grains

16.5

17

16

15

11

Urea

2

2

2

2

2

Molasses

42.5

34.5

30.9

29.4

27.8

Wheat bran

2

2

4

4

8

Groundnut hulls

15

20

20

20

19

Common salt

1

1

1

1

1

Limestone powder

1

1

1

1

1

Calculated ME, MJ/Kg † †

10.9

10.9

11.1

11.2

11.3

Calculated CP, %

14.7

14.7

14.8

14.5

14.6

0HS, 25HS, 50HS, 75HS and 100HS are diets with 0, 25, 50, 75 and 100% Karkade seeds crude protein

  Screw- press extracted ;  †† Calculated according to MAFF (1975)


Animal of  group 0HS had the control diet while those of group 25HS, 50HS, 75HS and 100HS had the diets that contained 25%, 50%, 75% and 100% Karkade seed protein. Daily feed allowances were served to each group ad libitum as one meal at 8 am. Salt lick and water were available all the times. Green Berseem (Medigaco sativa) was given to each group at a rate of 2 kg/head/week. The fattening period extended for 84 days during which live weight and body measurements were taken weekly and after an over night fast except for water. Food intake was determined daily as the difference between feed offered and refusals.

 

 Slaughter procedure

 

At the end of feeding period slaughter weight for each animal was taken after an over night fast except for water. The process was performed according to local Muslim practice where the jugular veins and carotid arteries were severed. The cold carcass was split into two equal halves. The head was separated from carcass between the occipital bone (Os occipitale) and the first cervical vertebra (Atlas). The forefeet were separated between carpus and metacarpus and the hind feet between tarsus and metatarsus joint. Evisceration was performed and all animal parts and organs were individually weighed and the hot carcass weight was registered. The cold carcass weight was taken following chilling at 1 C for 24 hours. The loin joint was removed from the left cold carcass side and dissected into muscle, bone fat and trimmings. The dressing out percentage was then calculated on the basis of hot and cold carcass weights.

 

Results 

Growth performance of animals

 

Animals’ performance is presented in table 3.


Table 3.  Growth Performance of Sudan Baggara bulls fed diets containing different levels of Karkade seeds

Item

Experimental groups

SE

LS

0HS

25HS

50HS

75HS

100HS

No. of animals

11

11

11

11

11

-

-

Initial live weight, kg

211

215

215

211

213

2.42

NS

Final live weight, kg

280

268

272

270

259

3.85

NS

Total gain, kg

69.1a

53.2a

57.7a

59.1a

46.4b

3.01

*

Daily gain, Kg/head/day

0.82a

0.63a

0.69a

0.70a

0.55b

35.9

*

Daily DM intake, kg

5.48

4.74

4.88

4.95

4.89

-

-

FCE, Kg DM/Kg gain

6.85a

8.85ab

9.70ab

9.75ab

11.27b

0.65

*

Means bearing the same superscript are not significantly different.                                                           

LS = Level of significance;  SE = Standard error of mean;   *        (P<0.05)


All bull groups started with initial live weight ranging from 211 to 215 kg, which was not significantly different. The final live weight though not significantly different among the different treatment groups, but was lower in group 100HS in which karkade seeds protein replaced 100% of groundnut cake protein.

 

Total live weight gain was found to decrease with the inclusion of Karkade seeds protein in the diets. The decrease was only significant (P<0.05) between group 100HS and the other dietary treatment groups. Daily gain showed the same pattern of changes as total body gain and group 100HS was significantly (P<0.05) lower in daily gain than the other dietary treatment groups.

 

Daily dry matter intake (DMI) was greater in group 0HS and feed conversion efficiency (FCE) deteriorated with the increase of Karkade seeds protein, but was only significantly (P<0.05) different between group 0HS and 100HS.

 

Slaughter data

 

The slaughter data results of bulls fed diets that contained different levels of Karkade seeds protein are given in table 4.


Table 4.   Slaughter data of bulls fed diets containing different levels of Karkade seeds protein

 

Experimental groups

SE

LS

0HS

25HS

50HS

75HS

100HS

Slaughter weight, kg

288

283

274

276

274

2.81

NS

Empty body mass, kg

242

235

229

235

229

2.67

NS

Hot carcass weight, kg

141

137

134

140

133

1.67

NS

Cold carcass weight, kg

139

134

131

136

130

1.77

NS

Half carcass weight, kg

72.4

69.7

68.6

71.5

67.9

0.82

NS

Fifth quarter weight, kg

101

98.3

94.9

94.5

95.8

1.53

NS

Dressing, %, (on EBM base)

58.4

58.2

58.5

59.8

58.1

0.38

NS

Dressing, %  (on slaughter wt base)

49.0

48.3

48.8

50.6

48.4

1.36

NS

Chiller shrinkage %

1.82

2.39

2.24

3.14

2.44

0.27

NS

 † Empty body mass - hot carcass weight


No significant differences were noticed between the groups. The highest slaughter weight (288 kg) was attained by animals of group 0HS, while the least slaughter weight (274 kg) was attained by animals of group 50HS and 100HS.

 

Empty body mass (EBM) was also not significantly different between the treatments. Bulls of group 0HS had the highest EBM (242 kg) and those of group 50HS and 100HS had the least EBM (229 kg).

 

Animals of group 0HS produced the heaviest hot carcass weight   (141 kg), and group 100HS animals produced the lightest hot carcass weight (133 kg). Cold carcass weight showed the same pattern of changes as hot carcass weight with no significant differences between the treatment groups.

 

The fifth quarter weight (empty body mass - hot carcass weight) showed no significant differences between the treatments. Animals of group 0HS attained the greatest weight (100.78 kg), while animals of group 75HS attained the lowest weight (94.51 kg).

 

No significant pattern of change was found in dressing percentage with the exception of animals of group 75HS which had the highest dressing percentage. Chiller shrinkage did not differ between the treatment groups. Animals of group 75HS showed the highest shrinkage (3.14%), while those of group 0HS showed the least shrinkage (1.82%).

 

Composition of loin joint

 

Table 5 represents composition of loin joint.


Table 5.  Composition of Loin joint of bulls fed diets containing different levels of Karkade seeds protein

 

Experimental groups

SE

LS

0HS

25HS

50HS

75HS

100HS

Loin joint, kg

5.03ab

4.73a

4.77a

5.38b

4.85ab

9.36

*

Muscle, %

62.2

66.6

61.4

63.0

65.5

4.32

NS

Bone, % 

20.5

23.7

24.9

23.8

24.1

2.64

NS

Fat, % 

8.55

5.82

6.08

5.95

5.10

2.30

NS

Trimmings, %

6.56

6.90

7.55

6.32

7.40

0.48

NS

Muscle/ Bone, %

3.04

2.82

2.47

2.65

2.72

1.05

NS

Muscle/ Fat, %

7.28a

11.4b

10.1ab

10.6ab

12.8b

5.23

*


Weight of loin joint was significantly (P<0.05) different between group 25HS and 75HS and group 50HS and 75HS. Loin joint from group 75HS showed the highest weight (5.38 kg) and that from group 25HS showed the least weight (4.73 kg). Muscle, bone, fat and trimmings weights were not significantly different between the treatments. Muscle of loin joint of animals from group 25HS was the highest (66.6%) among the treatment groups and the least weight was achieved by group 50HS (61.4%). Bone proportion was greater (24.1%) in loin joint from animals of group 100HS and least (20.5%) in the joint from animals of group 0HS. Fat content of loin joint from animals of group 0HS was the highest (8.55%) and was the least (5.1%) in loin joint from animals of group E. Group 50HS achieved the highest (7.55%) trimmings content of loin joint and group 75HS (6.32%) was the least. Muscle-to-bone ratio was highest (3.04) in group 0HS and least (2.65) in group 50HS. Conversely group 100HS recorded the highest (12.8) muscle-to-fat ratio and group 0HS attained the least ratio (7.28). The difference was only significant (P<0.05) between group 0HS, 25HS and 100HS.

 

Body components

 

Body components computed as percentage of empty body mass are given in table 6.


Table 6.   Body components of bulls fed diets containing different levels of Karkade seeds protein (% of EBM)

 

Experimental groups

SE

LS

0HS

25HS

50HS

75HS

100HS

Head

6.88

7.43

6.95

7.22

7.21

9.40

NS

Hide

8.34a

8.18a

7.67b

7.71b

8.22a

0.13

*

Empty stomach

3.72

3.82

3.98

3.81

3.49

8.39

NS

Empty intestines

2.53

2.63

2.71

2.66

2.73

5.61

NS

Liver

1.45

1.39

1.47

1.37

1.42

2.31

NS

Heart

0.43

0.46

0.47

0.45

0.46

7.89

NS

Lungs and trachea

2.09

2.08

1.99

2.28

2.16

5.57

NS

Kidneys

0.28

0.27

0.31

0.28

0.28

7.17

NS

Four feet

2.71

2.94

2.91

3.01

2.84

6.01

NS

Genital organ

0.51

0.55

0.52

0.51

0.52

1.77

NS

Mesenteric fat

0.31a

0.32a

0.43b

0.44b

0.41b

1.79

*

Omental fat

0.99a

0.66b

0.79ab

0.75b

0.79ab

3.62

*

KKCF

0.84

0.68

0.70

0.68

0.70

3.28

NS

Spleen

0.41

0.36

0.38

0.37

0.41

1.25

NS

Tail

0.55

0.68

0.65

0.61

0.66

2.23

NS

Gutfill

19.2

20.4

20.2

19.3

20.8

1.03

NS

†  Kidney Knob and Channel Fat


No significant differences were observed for body components among the treatments, except for hide weight, mesentery and omental fat. Hide of animals in group 0HS was the heaviest (8.34%) and that of animals in group 50HS was the lightest (7.67%). Animals of group 0HS and 75HS contained the highest percentages (0.99% and 0.44%) of omental and mesenteric fat respectively. Animals of group 0HS and 25HS contained the least percentages (0.31% and 0.66%) of these visceral fat depots, respectively. kidney knob and channel fat though not significantly different between the treatment groups was heavier (0.84%) in animals of group 0HS and lighter (0.68%) in animals of group 25HS and 75HS. Gutfill was heavier (20.8%) in animals of group 100HS and lighter (19.2%) in animals of group 0HS.

 

When analysis of variance (ANOVA) for regression was performed for animals growth performance, slaughter data, composition of loin joint and body components, only feed conversion efficiency and slaughter weight were significantly (P < 0.05) different (table 7).


Table 7.  Analysis of variance for regression

 

M S

F Ratio

L S

Daily gain, Kg/head/day

0.023

4.18

NS

Daily DM intake, kg

0.095

1.23

NS

FCE, Kg DM/Kg gain

9.38

26.05

*

Slaughter weight, Kg

122.56

10.99

*

Discussion

Growth performance

 

Daily dry matter intake (DMI) was not significantly different between the treatment groups, although it decreased with the inclusion of Karkade seeds. Recorded results for DMI were similar to that reported by Babiker (1999) and slightly less than that showed by Mohamed (1999), Turke (2002) and El-Tahir (1994) who reported DMI of 6.84, 7.87 and 7.33 respectively for the same type of cattle intensively fed. Daily gain showed the same pattern of changes as DMI and animals of group 100HS had the least significantly (P<0.05) daily gain than the other treatments. Animals of group 0HS which were fed a diet containing groundnut cake only had the highest daily gain. This reduction in daily gain particularly when Karkade seeds protein replaced 100% of groundnut cake protein could be due to protein quality differences where the latter supplied more bypass protein than the former and/or due to oil content of the diets as Karkade seeds have more crude fat than groundnut cake table (1). These two factors might also have affected diet digestibility. Daily gain in this study was comparable to the value 0.77 Kg reported, by Babiker (1999)   for the same breed fed on starch and glucose by-product (Protofeed).

 

The highest final live weight of group 0HS could be attributed to their high total body gain, while the least value of group E was attributed to their low total gain. Mean final live weights of animals in this study (270 kg) was typical to that reported by Mohamed (1999) for the same breed fed ad lib on diets of different dietary energy levels that ranged from 8.5 to 11.5 MJ/kg. However, average final live weight of animals in this study was higher than that reported by Babiker (1999) for the same type of cattle. This could be attributed to dietary differences and to the difference in feeding period that extended for 60 days in the latter study and for 84 days in this study.

 

The superior total body gain of group 0HS animals compared with those of group 100HS could be attributed to their differences in rate of gain and feed conversion efficiency. The overall mean weight of total body gain (57.1 kg) attained by animals in this study was in agreement with that reported by Mohamed (1988) who studied the utilization of unprocessed sorghum stover supplemented with different levels of concentrate on performance of Sudan Baggara cattle. Animals in the latter experiment achieved a total body gain of 58.8 kg.

 

The observed decrease in FCE with the increase of the replacement level of Karkade seeds protein coincided with changes in total gain and could be the major factor in these changes. Feed conversion values of animals of group 25HS, 50HS and 75HS were similar to values (8.6, 10.8 and 9.5) of the same cattle type finished on diets of different dietary energy levels that ranged from 8.5 to 10.5 MJ/Kg, Mohamed (1988).

 

Slaughter data

 

All slaughter data showed no significant differences between treatments. Animals of group 0HS (control) attained the highest (288 kg) slaughter weight, while animals of the other groups attained lower slaughter weights. This could be assigned to the superior daily gain of group 0HS (0.82 kg) compared to the other treatment groups.

 

Although the fifth quarter weight showed no significant differences between the treatments, animals of group 0HS attained the highest fifth quarter than the other treatment groups. This could be attributed to the high empty body weight of animals of group 0HS compared to that of the other treatment groups. Carcass weight reduction with replacement of groundnut cake protein by Karkade seeds protein particular at 100% replacement level could be ascribed to changes in empty body mass and body components as head, empty stomach and intestines, four feet and mesenteric fat.

 

Chiller shrinkage though not significantly different between the control and other treatment groups yet it increased with inclusion of Karkade seeds protein in the diet and here the thinner back fat thickness of the treatment groups could be the reason as fat particularly subcutaneous fat acts as an insulator preventing loss of moisture from the carcass.

 

Body components  

 

Body components and tissues showed no significant differences between the treatment groups except for hide, mesenteric and omental fat weights.  Head, hide, four feet, alimentary tract, heart and liver are an early maturing body parts and organs which are expected to change little with type of diet and that reflected the lack of significant differences observed in this study. Body fat depots are late maturing tissues and are affected by dietary energy level. The decrease in the percentage of omental and KKCF as groundnut cake protein was replaced by Karkade seeds protein in this study coincided with the decrease of subcutaneous fat over the eye muscle and could be attributed to dietary differences. In addition to these variations in empty body weights between the different treatments could be implicated (Geay 1975).

 

Conclusion

 

Acknowledgment 

Authors would like to acknowledge with gratitude the German Academic Exchange Service (DAAD) for providing a scholarship that allows conducting this research inside Sudan and at the Main Laboratory for Biochemical Analysis (HVA), Technical University of Munich, Germany.

 

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Received 16 June 2008; Accepted 26 March 2009; Published 1 June 2009

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