The performance of sheep and goats fed crop residues in addition to limited grazing in the backyards of small-scale peri-urban farmers

A.K.Tuah¹, B.Dzowela² and A. N. Said³

¹Dept. of Animal Science, UST, Kumasi, Ghana
²ICRAF, Harare, Zimbabwe
³1LCA, Addis Ababa, Ethiopia

Abstract

The performances of sheep and goats raised in the backyards of peri-urban farmers were studied. The animals grazed for a limited period of the day (14.00 h to 18.00 h) and were also fed cassava and plantain peels. The animals were weighed every two-weeks. The birth weights of lambs and kids born were where possible recorded together with dates of birth. Weights of animals at birth, 4 months and 12 months were used to calculate pre-and post-weaning growth rates. The quantities of peels of cassava and plantain fed were recorded once a week for 30 weeks. The in sacco dry matter degradation and the in vitro gas production characteristics of the feeds were also studied.

The mean birthweights of lambs ranged from 1.6 to 3.0 kg, weights of lambs at 4 months and 12 months from 5 to 8 and from 14.2 to 25.5 kg, respectively. The pre-and post-weaning growth rates of lambs varied from 25 to 94 g/day and 12 to 52 g/day, respectively. The preweaning mortality of lambs ranged from 0 to 77%. The birthweights of kids ranged from 1 to 1.6 kg, and weights at 4 months from 5.9 to 8.5 kg. The preweaning growth rates of kids were between 36 and 62 g/day. The preweaning mortality rates of kids ranged from 0 to 9%.

The in sacco dry matter and in vitro gas production characteristics of the cassava and plantain peels indicated they were good quality feeds. The ratio of cassava to plantain peels fed was 2:1.

Introduction

There are about five million sheep and goats in Ghana. It is the policy of the Ghana Government to increase the production of small ruminants during the implementation of its medium-term agricultural development programme (Ministry of Agriculture 1988). It is envisaged that the sheep population would increase from 2.0 million in 1987 to about 6.4 million in the year 2000 and goat population from about 1.9 million to about 9.2 million in the year 2000. For cattle the corresponding figures are 1.2 million and 1.9 million for 1987 and 2000, respectively.

About 75% of these small ruminants are raised by small-scale rural and peri-urban farmers. This trend in ownership is not expected to change with the envisaged changes in populations. The farmers confine their animals during most of the day in order to prevent damage to crops. The crop farms are now closer to the villages than in the past because of increased human population exerting pressure on arable lands. During the dry season, dry forages may be burnt by bushfires causing serious feed shortages. At present, farmers are feeding crop residues both during the wet and dry season. These crop residues are mostly generated by their own household cooking. Unlike the urban small-scale backyard farmers, they are unable to purchase agro-industrial by-products such as wheatbran, brewers' grains and oil seed cakes to feed their animals due to financial constraints. Most of the crop residues they feed are generally low in nitrogen and possibly minerals and vitamins, especially A and E. Sometimes they also feed limited quantities of foliage of multipurpose trees and shrubs harvested from their farms or along roadsides.

There is a dearth of information on the performance of small ruminants in these small-scale rural and peri-urban farmers. The objective of this monitoring project was to assess the performance of animals belonging to small-scale farmers in a village near the university campus, Kumasi.

Materials and methods

The trial was conducted in Ayeduasi village, which shares borders with the University campus. It is increasingly becoming urbanised because of acquisition of land for building houses by University staff members and other people. The major occupations of the people are crop farming and the raising of small ruminants. Thirteen farmers were initially selected for the study based on their willingness to participate in the programme.

Animals housing, feeding and management

The animals were of different age groups and each farmer owned a few sheep or goats or both. The breed of the sheep was not known since there has been uncontrolled crossing of the dwarf sheep with the larger Sahelian breed. The animals were kept indifferent types of pens, some with and others without roofs. Most of the houses had no side-walls thus allowing rain to fall on the animals. Those with walls were also built up to the roof and lacked proper ventilation. The floors of the pens were of mud and no bedding was provided. The floors were swept daily in the morning but were generally wet; sanitary conditions were poor especially during the rainy season.

The animals were kept indoors for most of the day (until about 1400 h) and were released to graze around the village for about four hours. The animals did not normally move outside the village boundaries because of the limited grazing time available. They were fed crop residues mainly in the morning, These were being kept overnight. The animals were not treated against ecto- and endo-parasites. Sick ones were occasionally treated, when money for drugs was available. The people seem to have forgotten most of local herbs used for treating animals, where many herbs seem to have disappeared.

Breeding was not controlled. Since almost all animals in the village mixed during grazing, sires of lambs and kids were not known.

Data collection

All .animals in the sample were eartagged at the beginning of the experiment together with lambs and kids born during the course. All animals were weighed every two-weeks. Birthweights were recorded where possible. Since the farmers did not have scales and the data collectors were not present, some birthweights were missed. Birth dates however could be remembered by the farmers. Data collection for sheep started in November 1991 and for goats in July 1992.

The quantities of feeds fed to animals in confinement were weighed once a week for 30 weeks starting from November 1991. The feeds were offered and weighed in the evenings, and the refusals the following morning. The feeds were given in feed troughs. Samples of feeds were taken. Mortalities of lambs and kids were recorded.

The in sacco dry matter degradation characteristics of the feeds offered were studied using the method of Ørskov et al (1980). The incubation periods were 2, 4, 8, 16, 24, 48, 72 and 96 h. The in vitro gas production characteristics of the feeds were studied using the method of Menke et al (1979). Samples of the feeds were analysed for dry matter and nitrogen in accordance with the methods of Association of the Official Analytical Chemists (AOAC 1980) and the Kjeldahl method (AOAC 1980), respectively.

Results and discussion

No statistical analysis was carried out because of the small numbers of animals. The means for each farmer for each parameter were calculated and used in the discussion. The breeds of the sheep were also not the same for all the farms. Only 8 out of the 13 farmers the project started with continued until the end.

The mean birthweights of the lambs for the different farms ranged from 1.6 to 3.0 kg (Table 1). For the kids the mean birthweight ranged from 1 to 1.6 kg (Table 2).

Table 1. Performance data on lambs.

Bw = Birth weight; Ww: Weaning weight; PreWGR: preweaning growth rate ; Post WGR = Postweaning growth rate ;
Pre-Wm =Preweaning mortalities.

Table 2. Performance data on kids.

Bw: birth weight; Ww: weaning weight; PreWGR: preweaning growth rate.

Since the animals are weaned naturally, the weight at four months was taken as the weaning weight. The mean weaning weights of lambs ranged from 5 to 14 kg (Table 1).

The heavy lambs (> 10 kg) were Sahel × dwarf cross breeds, whereas those weighing <7 kg were most dwarf breed. For kids, the mean weaning weights ranged from 5.9 to 8.5 kg (Table 2).

The mean preweaning growth rates of the lambs ranged from 25 to 94 g/day (Table 1). The mean preweaning growth of the kids ranged from 36 to 62 g/day (Table 2). The mean weights of lambs at 12 months ranged from 10 to 26 kg (Table 1) with mean postweaning growth rates ranging from 12 to 52 g/day. There were no corresponding weights for kids as none reached 12 months at the end of the monitoring period.

Out of the 115 lambs born during the study, 16 (7.5%) were as twins (Table 1). For the 53 kids born (Table 2) 24 (45.3%) were as twins and three were born as triplets (5.67).

The preweaning mortality rates of the lambs ranged from 0 to 77% while those of kids ranged from 0 to 9%.

All farmers fed cassava and plantain peels daily at a ratio of about 2:1. Only five farmers fed foliage of Ficus exasperata on one occasion each during the trial. The intakes of forage could not be measured. Assuming that all animals between 4 and 12 months consumed about half the quantity of these supplements supplied as adults, the quantities of the peels eaten per adult ranged from 124 g/head/day to 30 g/head/day on dry matter basis. Since the quantities of grass consumed were not known it is difficult to calculate what percentages of feed intake these figures represent. It however seems that the animals were adequately fed because of their performance. The forages consumed might have supplied enough nitrogen minerals and vitamins which mostly likely were deficient in the peels.

The plantain peels were also green and were mostly likely rich in vitamin A precursors.

The in sacco degradation and the in vitro gas production characteristics of the feeds indicate that they are at least higher in digestible dry matter, and hence organic matter or energy (Table 3) than cereal straws (A.K.Tuah, D.B. Okeni and F.Y. Obese, unpublished data).

Conclusions

The performance of sheep and goats in the backyard farms of the peri-urban small-scale farmers compared favourably with the reported performance of these two species on the university farm, Kumasi.

Until further restrictions are placed on these animals with respect to grazing, their productivity may not be reduced with the restricted grazing time and present level of supplementation of the diets with cassava and plantain peels. The high mortality rates of the lambs, however, need further investigation. There is also the need to conduct research into housing problems.

Acknowledgements

This study was funded by AFRNET and ILCA and AFRNET are acknowledged.

References

AOAC (Association of Official Analytical Chemists). 1980. Official Methods of Analysis. 13th edition. AOAC, Washington, DC, USA.

Menke K.H, Raab L., Salewski A., Steingass H., Fritz D. and Schneider W. 1979. The estimation of the digestibility and metabolizable energy content of ruminant feeding stuffs from the gas production when they are incubated with rumen liquor in vitro. Journal of Agricultural Science (Cambridge) 93:217–222.

Ministry of Agriculture 1988. Medium Term Agricultural Development Programme. Working Paper 4. Livestock subsector. Ministry of Agriculture, Accra, Ghana.

Ørskov E.R., Hovell F.D. and Mouhl F.1980. Tropical Animal Production 5: 195–213.

Performances d'ovins et de caprins de basse-cour recevant des résidus de récoltes en plus d'un pâturage limité chez les petits paysans des zones péri-urbaines

Résumé

Les performances d'ovins et de caprins élevés en basse-cour par les petits paysans des zones péri-urbaines ont été étudiées. Les animaux ont pâturé pendant une durée limitée au cours de la journée (de 14 à 18 heures) et ont reçu des pelures de manioc et de banane plantain. Ils ont été pesés toutes les deux semaines. Les poids à la naissance des agneaux et des chevreaux ont, dans la mesure du possible, été enregistrés avec leur date de naissance. Les poids à la naissance, à 4 mois et à 12 mois ont été utilisés pour calculer les taux de croissance avant et après sevrage. Les quantités de pelures de manioc et de banane plantain distribuées ont été enregistrées une fois par semaine pendant 30 semaines. Les caractéristiques de la dégradation in sacco de la matièe sèche et celles de la production in vitro de gaz ont également été étudides.

Les poids des agneaux variaient de 1,6 A 3 kg à la naissance, de 5 à 14,2 kg à 4 mois et de 8 à 25,5 kg à 12 mois. Leurs taux de croissance avant et après sevrage allaient respectivement de 25 à 94 g/j et de 12 à 52 g/j et leur mortalité avant sevrage variait de 0 à 78%. Quant aux chevreaux, leur poids à la naissance variait de l à 1,6 kg, et leur poids à 4 mois de 5,9 à 8,5 kg. Leur taux de croissance avant sevrage allait de 36 à 62 g/j et leur taux de mortalitd avant sevrage de 0 à 9%.

Les caractéristiques de la dégradation in sacco de la matière sèche et celles de la production in vitro de gaz indiquent que les pelures de manioc et de banane plantain, servies dans un rapport de 2 à 1, sont des aliments du bétail de bonne qualité.