1. Influence of restricted suckling period on
milk yield of Bos taurus x Bos indicus cows and live weight change of
calves:
Manuel Hernández, Leopoldo Gabaldón and Jorge Combellas
An experiment was carried out to evaluate the effect of three periods of restricted suckling on milk yield and other productive variables of Bos indicus x Bos taurus cows and on the performance of their calves. Thirty six Brahman x Holstein cows were assigned using a completely randomized design to three weaning age treatments: at 8, 16 and 24 weeks. The calves were suckled by their dams for 30 minutes after the morning milking and received 1 to 2 kg/day concentrate, cut forage ad libitum and grazed on paddocks of Cynodon dactylon for 7 h daily. The cows were milked twice a day, received 2 kg/day of concentrate per milking and grazed on pastures of Cynodon dactylon and Digitaria swazilandensis. Total milk was 2249 kg/lactation without differences between treatments (P>0.05). Daily milk yield decreased by 23 % on average during the week following weaning, but the trend of the lactation curve was recovered after 2 to 4 weeks. Decreasing the suckling period from 24 to 8 weeks increased saleable milk from 1694 to 2175 kg/lactation (P<0.05) and decreased suckled milk from 430 to 179 kg (P<0.01). The liveweight gain of the calves was not affected.
These results show that by decreasing weaning age to 8 weeks, the advantages of restricted suckling are maintained but but the quantity of saleable milk is increased. The growth rate of the calves is not affected as they eat more concentrates to compensate for the reduction in suckled milk. For every 1 kg of additional concentrate used, 5 kg of additional milk is available for sale, with positive economic returns in most price conditions.
2. Biodigester effluent as protein supplement for indigenous (Bos
indicus) growing bulls:
S A Chowdhury
The possibility of using anaerobically fermented cattle manure (biodigester effluent) as a source of protein on a straw based diet for growing indigenous (Bos indicus) bulls was studied. Eight bulls (256 ±33.1 kg liveweight and 18.5 ±3.86 months old) were randomly allocated to two experimental diets having either 0.5 kg/day mustard oil cake or biodigester effluent (from cattle manure) ad libitum, as source of protein. Both groups of animals had an ad libitum supply of rice straw (enriched with urea 3%; molasses 15%) together with daily quantities of 1 kg wheat bran, 0.3 kg molasses, 40 g of oyster shell powder and 70 g of salt/head. Compared to the fresh cattle manure, the effluent had 81% higher total nitrogen (N) and 24% lower acid detergent fibre (ADF) content. None of the effluent-fed animals showed any symptoms of behavioral or physiological abnormalities. When the animals were fully adapted, effluent constituted 13% of the total DM intake (about 17 kg fresh material/day). Straw dry matter intake was the same (104 g/kg W0.75/d) for both groups, but effluent-fed animals had higher (P<0.05) organic matter intake and lower (P<0.05) dry matter diestibility than those fed mustard oil cake. There were no differences (P>0.05) between dietary treatments in: digestibilities of organic matter, nitrogen and ADF; in calculated microbial N yield; in N retention and growth rate. It is concluded that biodigester effluent can be fed to Bos indicus bulls but that it is probably inferior to mustard oil cake as a supplement for a straw-based diet.
3. Low cost biodigesters for zero grazing smallholder dairy
farmers in Tanzania
Innocent Rutamu
This report presents the findings of a research project sponsored by African Development Foundation (ADF) and carried out in Tanga, Muheza, West and East Usambara parts of Tanzania between the months of August 1994 and January 1996.
Forty-six biodigesters were installed in selected villages. The gas produced was of low pressure, of right composition and safe to use. It was also observed that differences in attitude and animal feeds in our operation zones did not significantly affect gas production and composition. The biodigesters are to a certain extent fragile and there is a need for protection against perforation and sunlight to increase durability. The gas produced if well used could save up to more than 50% of cooking energy needs.
It was observed that, on average, 5 hours of household labor were saved per day because of the introduction of Biogas. The use of biogas alleviates the work load of women and makes it possible for men to participate in providing for energy needs at homestead level; a role which is otherwise traditionally women's. It was estimated that the cost of investment could be recovered in a period in the range of 9 to 18 months, according to the relative prices of materials and of charcoal. Furthermore, the use of low-cost biogas reduces the cutting of highly valuable hard wood and hence protects the environment.
4. Use of local ducklings to control insect pests and weeds in
the growing rice field
Bui Xuan Men, Tran Kim Tinh, T R Preston*, R Brian Ogle
and Jan Erik Lindberg**
An experiment was conducted on a smallholder farm in Omon district in the Mekong Delta to evaluate the ability and efficiency of local ducklings in controlling damages from insect pests and weeds in the growing high yielding rice field. The trial included 4 treatments allocated at random in 4 blocks, each of 33*210m, in a direct seeded rice area. The treatments were: (1) rice area managed with complete chemical (CtrP), (2) rice area fertilized with 50% of the nitrogen applied to CC plus ducks (DU-N/2), (3) rice area with only ducks without any chemicals (DU O), and (4) rice area without any chemicals or ducks (CtrN). The ducks were introduced into the growing rice plots at two weeks of age when the rice had been seeded for 22 days and removed at 52 days when the plants started flowering. A mash of broken rice and fish meal was supplemented to the ducks throughout the growth cycle.
The rice yields were 4,240, 3,888, 2,176, and 496 kg per hectare (P<0.05) for the CtrlP, DU-N/2, DU Oand CtrN treatments, respectively. Duck mortality during the experiment was zero. Weights at 63 days were 1,313 and 1,300 for the DUN/2 and DU treatments, respectively. The net economic benefits were highest for the DUN/2 treatment.
Key words: Local ducks, growth, rice production, integrated pest management, weeds
5. Growth rates of fat-tailed sheep tethered or free on range
compared to free in a Leucaena leucocephala pasture
Damião Nguluve and James P Muir
Dry season average daily liveweight gains of castrated, growing Landim fat-tailed sheep tethered on native grass (TR) or free-ranged in a cultivated pasture with a Leucaena leucocephala over-story (FL) were compared to sheep free-ranged on native grass (FR). During the year with 591 mm rainfall, growth rates (g/day) were 15.2, 37.8 and 25.8 for the respective treatments. During the year with 780 mm rainfall, growth rates were 17.0, 89.8 and 39.5 for the respective treatments. High rainfall versus low rainfall year differences in growth rate were not as large for TR animals (12% greater for high rainfall) compared to FR (53% greater) or FL (138% greater). The trial indicated that tethering fat-tailed sheep, thus limiting grazing selectivity, decreased growth rate compared to untethered animals. It also indicated that sheep with both greater herbaceous biomass and high crude protein leaves (from L. leucocephala) to select from had higher growth rate compared to animals in mixed cattle/sheep herds on native pasture.
6. Participatory research with farmers:
Lessons gained from postgraduate training courses in Vietnam
John Kornerup Bang
An evaluation was made of 17 students who participated in three MSc courses in sustainable agricultural production in Vietnam. The evaluation focussed on three main aspects reflecting an approach that seeks to combine an ecological perspective, focus on resource poor farmers (RPF) and the participation of these farmers in the process of research and extension. Overall, 65% of the students were performing within a framework generally corresponding to this combination. Aspects concerning a technological perspective relevant for the environment and RPF stood strongest. It is crucial that participatory processes are embedded in a relevant technological perspective, as a pure focus on the farmers perspective is illusory just as the farmer’s perspective tends to be narrow and opportunistic. However, even though a firm instrumental participatory performance was identified, it is recommended that for future courses there should be more emphasis on the participatory processes in a more open-ended way. This is foremost a prerequisite to create more commitment and to build up capacities among farmers and thereby address in a better way critical concerns such as the sustainability of the technology together with it’s lateral spread. The final perspective of the proposed approach is the concern that policy-changes towards the kind of development, so highly emphasised recently, that is based on a strong focus on the environment, and the needs and priorities of the intended beneficiaries through their participation in the process, are worth only little if the persons to carry out this task have no expertise in the subject matter. The actual performance of the students analysed represents serious potentials in addressing this concern.
7. Availability and use of work animals in the middle Andean hill farming
systems of Bolivia
J T Dijkman, B G Sims* and L Zambrana**
A participatory rural appraisal (PRA) was designed to analyse current availability and use of draft animals in farming systems in the middle Andean hills, and to prepare detailed recommendations for demand-led draft animal research. The PRA was carried out between May and October of 1996 in six communities in three provinces (Capinota, Ayopaya, Tiraque) of the Cochabamba Region in Bolivia. These provinces were selected as they represent the broad spectrum of agro-ecological zones, socio-economic circumstances and work animal usage within the region. The PRAs were carried out within a collaborative framework of farmers, local institutes and NGOs. The preparatory study, together with a confirmatory workshop which was organised in October 1996 and attended by community representatives, intermediate users and scientists, clearly identified draft animal husbandry (animal health, feeding, diversification of animal use and animal housing), implements (transport, soil cultivation, seeding, weeding and harvesting) and soil and water conservation (equipment and practices linked to fodder production) as major limiting factors in the farming systems within the target area.
8. Ensilaje de vísceras de pescado Cachama blanca (Piaractus brachyponum)
como fuente de proteína para la alimentación de cerdos de engorde en una dieta
con aceite crudo de palma (Elaeis guineensis - Elaeis oleifera)
Julio E Bermudez, Jairo H Rodriguez, Alvaro Ocampo y Lourdes Peñuela*
Thirty pigs were fattened from 20 to 80 kg liveweight using the ensiled digestive tract of a fresh water fish (Piaractus brachyponum) to replace 0, 50 or 75% of soya bean protein in diets based on crude oil from the African Oil Palm (Elaeis guineensis - Elaeis oleifera). Liveweight gains were: 523, 546 and 495 g/day with feed conversion (MJ digestible energy/kg gain in liveweight) of 46.2, 39.2 and 46.2, respectively, for 0, 50 y 75% substitution of the soya bean protein. Carcass yields averaged 80% and back fat thickness was less than 2 cm on all treatments.
It is concluded that the integrated system of fish production with pig fattening, using the ensiled fish waste, offers comparative advantages over fish production alone, when social and environmental factors as well as economics, are taken into account.
Key words: Fish intestines, silage, Piaractus brachyponum,
African Oil palm (Elaeis guineensis - Elaeis oleifera, oil, pigs, fattening,
protein
9. Survey on family chicken farms in the rural area of N’Djaména, Chad L Y Mopate and M Lony
[Editors' Note: This article, edited and translated from the original French by E F Guèye, was first published in the INFPD (International Network on Family Poultry Development) Newsletter Vol. 8 No. 4, October-December 1998, and is reproduced with the permission of the editors of INFPD and the authors]
An investigation on the status of family chicken systems was carried out on 57 chicken farms, located in 10 villages in the rural area of N’Djaména, Chad. It was found that chicks represented 51.2 percent of the flock. The sex ratio was six hens for one cock, and the average flock size per household was 16.3±11.1 chickens. Hatchings represented the most important intakes, while the principal offtakes consisted of mortality, sale and predation. The causes of mortality were diarrhoea, ectoparasites and respiratory diseases. The average mortality rate was 17 percent and the production efficiency 16 percent. Average traits of 125 hens were age 19±11 months, weight 1.2±0.3 kg, number of eggs per clutch 10.5±2.8, number of clutches per year about three, hatchability 79 percent, survival rate of chicks at weaning 55 percent, brooding period 52 days and interval between clutches from 80 to 90 days. Adequate disease control, reduction of chick losses and improvement in husbandry practices are recommended.
10. A tropical forage solution to poor
quality ruminant diets: A review of Lablab purpureus
Andrea M Murphy and Pablo E Colucci*
The literature concerning the agronomic characteristics and nutritive value of the legume Lablab purpureus (Lab lab) is reviewed.
Lablab purpureus combines a great number of qualities that can be used successfully under various conditions. Its first advantage is its adaptability, not only is it drought resistant, it is able to grow in a diverse range of environmental conditions world wide. Staying green during the dry season, it has been known to provide up to six tonnes of dry matter/ha.
Being palatable to livestock, it is an adequate source of much needed protein and can be utilised in several different ways. It can be grazed in a pasture setting or as a companion crop to maize, cut as hay, or mixed with corn silage. In several experiments it has been observed to increase livestock weight and milk production during the dry season.
Lablab purpureus with its ability to out-yield conventional crops, especially during the dry season, and its enhanced nutritive value, is a fodder crop of great significance for the Tropics. Lablab can be used advantageously as a cover crop. Its dense green cover during the dry season protects the soil against the action of the sun's rays and decreases erosion by wind or rain. As green manure it provides organic matter, minerals and fixes nitrogen into the soil thereby improving crop yields in an economic and environmentally friendly manner.
Though lablab is known in many countries and has the capability of being an outstanding resource for agricultural systems in the tropics, it is not being used to its full potential. In many areas where lablab could be beneficial, ability to buy seed is restricted by economic constraints and producers' willingness to take the risk in trying a new practice is guarded by traditional paradigms. Effort must be devoted to conducting more research to extend both technical and practical knowledge about lablab so that its full potential may be achieved. Thus helping to improve the living conditions in countries where shortages of human food and animal feedstuffs exist.
Poster: Urea supplementation of rice
straw for Sindhi x Yellow cattle; sprayed in solution, as a soft cake or hard
block
Ho
Quang Do, Vo Van Son, Do Vo Anh Khoa and Nguyen Thi Kim Khang
Twelve growing cross-bred heifers (Sindhi X Yellow cattle) of 124 kg (SD=13), receiving a basal diet of ad libitum rice straw and restricted fresh grass (about 4 kg/head/day), were allocated to four treatments: urea sprayed on the straw (50 g in 1.5 litres water, daily); as a hard block (10% urea) offered ad libitum; as a soft cake (10% urea) offered at 500 g/head/day; and unsupplemented control. Intakes of rice straw and of total dry matter were higher (P=0.001) on all supplement treatments compared with the control. The cattle ate all the soft cake that was offered (500 g/day) but those offered the hard block ate only 209±3 g/day, less than half the amount consumed of the soft cake. Growth rates were highest (P=0.001) with the soft cake supplement (280 g/day) followed by the hard block (160 g/day), the spray solution (125 g/day) and the unsupplemented control (63 g/day). Growth rate was positively correlated (R²=0.90) with the estimated intake of urea.