Livestock Research for Rural Development

Volume 11, Number 1, 1999

Abstracts of papers in LRRD, Volume 11, Number 1


Experiences in the management and exchange of electronic information for sustainable agriculture

Nicholas Waltham

Fundación CIPAV,Cra 35A #3-66, Cali, Colombia


This paper gives an overview of the experiences of the CIPAV Foundation in the area of electronic publication and the technologies that are used. It describes how CIPAV, while executing one of its flagship projects (the electronic journal: Livestock Research for Rural Development), has passed from a technologically simple system of electronic publication to use the most recent tools of HTML formatting and publication as a Home page on the WWW.

Key words: Information dissemination, electronic publishing, review, Internet


Connecting Bangladeshi Villages

Iqbal Z Quadir

Grameen Phone, Aarong House, Floor # 14-15-16-17, 65, Mohakhali C/A, Dhaka-1212, Bangladesh

Paper presented at Development Workers' Course: Women in Agriculture and Modern Communication Technology.
Tune Landboskole, Denmark, March 30-April 3, 1998.


Illustrated by the author's personal communication experience and the potential that good communication connections have,  in enabling development, the paper describes an initiative in Bangladesh that within a few years will bring cellular phones into the 35,000 villages covered by the Grameen Bank. The company - GrameenPhone - in a pilot program involving 150 villages has confirmed that the village phone concept is economically viable. It is concluded that microcredit should not be viewed as a narrow program to help the poor, but as a tool to release the entrepreneurial energy of the poor, which can meet the two important objectives of uplifting the economy and benefiting the poor.

Key words: Rural connectivity, cellular phones, microcredit, women, economic development


Productive performance of F1 compared with other 50% European-zebu crossbred cows for dual purpose systems in the Venezuelan tropics

Lucía Vaccaro, Armando Pérez and Rodolfo Vaccaro

Universidad Central de Venezuela, Facultades de Agronomía y de Ciencias Veterinarias,
Maracay, Venezuela


The performance of Holstein-zebu (F1H) and Brown Swiss-zebu cows F1 (F1BS) was compared with that of mixed inter se (MIS) crossbreds of 50% European-zebu inheritance, using 5054 records from 10 dual purpose farms in Venezuela. The F1H cows were mainly progeny of 41 USA Holstein bulls of positive genetic value for milk yield, while most BS bulls were of unknown or average genetic merit. The MIS cows were progeny of crossbred bulls of various genotypes, generally unselected for performance traits. Records included lactation and 244-day milk yield, days in milk, days open, calf weight at 4 months and calf mortality from birth to 4 months. Data were analysed using linear models which included the effects of breed group (3), farm (10), calving year (1989...1997), calving season (wet, dry), calving number (1..6+), and the first order interactions involving breed group.

Overall adjusted mean values (± SE) were 1637 ±35 kg total lactation yield, 1436 ±27 kg 244-day yield, 246 ±5 days in milk, 139 ±5 days open, 60 ±0.7 kg calf weight at 4 months and 8.6 ±1.6% calf mortality. The only significant breed group effects were found for milk yield (P <0.01) and days in milk (P <0.05), but the breed group x farm interaction was highly significant for these traits and days open. The HF1 ranked first for milk yield on nine of the ten farms. Overall, they exceeded the MIS and F1BS cows by 19% and 14%, respectively, for total milk yield and by 10% and 13% for days in milk, and showed no disadvantage for any trait. There were no significant differences in performance between the F1BS and the MIS cows. Coefficients of variation were closely similar for all groups.

It was concluded that F1 cows may offer an important advantage over commercial-type inter se crosses. The 19% increase in milk yield per lactation of the F1H cows may well compensate the practical disadvantages of the mating system required to produce them. However, the F1BS results showed that the advantage of the F1's does not always occur and may depend on the European breed used, and/or the quality of the sires within the breed. The use of MIS cows offers important practical advantages, especially for small farms, and their performance should be improveable through more systematic selection. There was no evidence that the performance of the progeny of crossbred bulls is unusually variable for traits of importance in dual purpose systems.

Key words: Dual purpose, F1, crossbreeding, milk yield, fertility, mortality

The productive water decontamination system: A tool for protecting water resources in the tropics

J Chará, Gloria Pedraza and Natalia Conde

Aquaculture and Recycling Research Group. Centro para la Investigación en Sistemas Sostenibles de Producción Agropecuaria (CIPAV) Carrera 35A Oeste # 3-66, Cali, Colombia.



Farming activities can cause important impacts on the environments due to the discharge of wastewater into streams, rivers and lakes. Wastewater treatment systems available for farms are highly specialised, costly to implement and maintain and therefore are beyond the means of most small and medium-scale farmers in the developing world. However, agriculture wastewater treatment can be effectively undertaken through biological processes involving the activity of microorganisms such as bacteria, algae, fungi, plants and animals. This approach has been used for many years in South East Asia in the integrated aquaculture-agriculture systems developed there. The Productive Water Decontamination System developed by CIPAV in Colombia uses this approach to reduce water and soil pollution, and converts the energy, organic matter and nutrients contained in the wastewater into elements that can be used in the farm, such as biogas, fertilisers, forages and food.

The system consists of a low-cost plastic tube biodigester and aquatic plant channels complemented by fish polyculture ponds and associated crops. Wastewater passes through the biodigester and then to the aquatic plant channels and the fishpond. As wastewater passes through the system, pollutants are transformed into biogas, aquatic plant biomass, food crops, and fish. In addition, Biochemical Oxygen Demand (BOD5) and suspended solids are reduced up to 60-70% in the biodigester and up to 97% in the complete system as compared to the untreated wastewater.With this system, water decontamination can be a profitable activity, economically and socially attractive for farmers and producers in general.

Key words: Wastewater decontamination, biological purification, integrated decontamination, biodigester, aquatic plants.

Overall view on the tradition of tapping palm trees
and prospects for animal production

Christophe Dalibard

International Relations Service, Ministry of Agriculture, Paris, France

"Neera [sap extracted from Borassus flabellifer] can be converted into Jaggery sweet as honey itself. This Jaggery is superior to cane Jaggery. Cane Jaggery is sweet, but Palm Jaggery is sweet and delicious; it can be produced worth crores of rupees. Palm Gur gives mineral salts too. Doctors have told me to eat Jaggery and I always eat Palm Gur. Nature has made this product in such a way that it cannot be manufactured in the Mills; it is produced in the Cottages. Where there are Palm trees, this Jaggery can be easily produced. Andhra Desha has thousands of Palm trees; there, Jaggery is produced in every hamlet. This is the way to banish poverty from the land. This also is an antidote to poverty."   Mahatma Gandhi  [From a speech delivered at the opening of the village industry exhibition in Brindawan Bihar (3 May 1939)]



Palm trees have proved to be efficient converters of solar energy into biomass in most agro-ecological zones of the tropical world. Most tapped palm trees gives a sap very rich in sugar (10 to 20%). For several millennia, many species of palm trees (including coconut) have been used for sugar production. Highly sophisticated techniques of tapping were developed through the centuries in Asia, Africa and America. High yields of sugar were obtained from palms that could continue for up to a hundred years of production. One of the main constraints on production in recent times has been the increasing lack of fuel needed for processing palm sap into sugar and the price thereof. Nevertheless, since trials of feeding pigs with fresh sugar palm sap were successfully initiated in an FAO project in Cambodia, there has been renewed interest in tapping palm trees for sap to be used as feed. A thorough review of the literature has shown that intensive pig rearing based on palm sap has already been practised by the Indonesians for centuries and was found to be a very efficient system for intensifying agriculture in some highly populated islands. In today's economy, developing animal production using palm sap as the main source of energy in the diet looks very promising: the land could sustain higher population densities through the intensification of crop and animal production within sustainable integrated systems for small farmers.

Key words: sugar palm, tapping, sap, livestock, feed


Liveweight gain of growing cattle offered maize meal or citrus pulp as supplements to diets based on poultry litter
and restricted grazing of low quality pastures

G Nouel and J Combellas

Universidad Central de Venezuela, Facultad de Agronomía, Maracay, Venezuela


Two experiments were carried out to evaluate the inclusion of a high proportion of poultry litter in the diet, mixed with citrus pulp or maize meal with or without a flavouring, and its effects on live weight (LW) gain of growing cattle grazing poor quality pastures at the end of the rainy season (E1) and during the dry season (E2). A third experiment (E3) was carried out with rumen fistulated animals to study the effect of these diets on some characteristics of rumen fermentation. In E1, 42 Bos taurus x Bos indicus males of 209 ± 33 kg were used to compare three treatments receiving in pens a mixture of 79% poultry litter, 1% common salt and 20% of citrus pulp (P) or maize meal with 0.05 % of a commercial flavouring (MF) or without it (M). All groups grazed during 16 h paddocks with standing forage of 3.72 ± 1.38 tonnes DM/ha in which Hyparrenia rufa and Trachypogon gracilis predominated. The remaining time the animals were stall-fed the experimental feeds in groups during 84 days. For P, M and MF daily intakes were 1.02, 1.45 and 1.36 kg DM/100 kg LW and LW gains were 0.51, 0.59 and 0.56 kg/day (P>0.05). The same diets were used in E2, but the paddocks were accidentally burned before the trial. The grazing periods were reduced to 8 h and 36 animals of 229 ± 26 kg were used. Standing forage of the regrowth was 1.24 ± 0.42 ton DM/ha. For treatments P, M and MF daily intakes were 2.02, 2.17 and 2.07 kg DM/ 100 kg LW and LW gains were 0.31, 0.53 and 0.48 kg/day (P<0.01). The differences between treatments observed during the dry but not at the end of the rainy season, could be related to the higher mixture intakes in the second trial and their effect on total energy consumption.

The same treatments were compared in E3 and an additional treatment (L) with poultry litter as the only supplement was included. A latin square was used with 4 animals of 159 ± 16 kg and periods of 17 days. The trial was carried out during the dry season and intakes per animal were measured, being higher in M and MF than P and L, with values of 3.41, 3.35, 2.18 and 1.25 kg DM/100 kg LW. No differences in rumen ammonia nitrogen concentration were observed, with mean values of 151, 156, 164 and 130 mg/litre, respectively.

Three conclusions could be derived from this study. The addition of an energy source to poultry litter in these conditions resulted in more than two-fold consumption increments. The substitution of maize meal by citrus pulp reduced LW gain during the dry season, when high levels of mixture intake were reached. And finally, the addition of a flavouring to diets based mainly on poultry litter and maize meal did not increase intake or LW gain of growing cattle.

Key words: Cattle, poultry litter, flavours, energy supplement, intake, growth

Sugar cane as replacement for Guinea grass
for growing goats

Le Diep Long Bien

Goat and Rabbit Research Centre, Son Tay, Hatay Province, Vietnam


A total of 15 weaned kids (4 months of age and initial liveweight from 8.4 to 9.8 kg), were allotted in a completely randomised design to five treatments which were offer levels of sugar cane and Guinea grass (Panicum maximum Jacq.) in proportions of 100:0, 75:25, 50:50, 25:75 and 0:100 (fresh basis). The other components of the diet were jack fruit leaves (Artocarpus heterophyllus), a molasses-urea block (10% urea), dried cassava root and rice bran. Over a 120 day period, the daily liveweight gain ranged from 52 to 63 g/day but did not differ among diet treatments (SE±8.5; P=0.95).

It is concluded that sugar cane can replace Guinea grass as the basal forage for growing goats without affecting performance. Sugar cane produces the most biomass when harvested in the winter season which is the period when Guinea grass is least productive. Thus the two forages complement each other for providing a sustainable year-round supply of forage for goats.

Key words: Sugar cane, Guinea grass, goats, growth

Duckweed versus ground soya beans as supplement for scavenging native chickens in an integrated farming system

Hong Samnang

Jesuit Service Cambodia, Phnom Penh, Cambodia


In order to compare the effect of duckweed, soya bean meal and broken rice on the live weight growth of scavenging chickens, 120  native chickens of mixed sexes were bought in the market and randomly allocated into three different treatment groups and two replications with 20 chickens in every treatment / replication group. There was one replicate of the treatments in the station and one in the village. In the station (the experimental farm of the Jesuit Service Cambodia) the birds on the three treatments scavenged in the same area of an integrated farm with fruit trees, biodigester and duckweed ponds. In the village, the treatments were in separate, but adjacent, households, each of which had an area with fruit trees, biodigester and duckweed ponds. At night-time the chickens were housed with individual access to the supplements. Three types of supplement were offered daily in the evening when the birds were confined: (Dw) 50g of broken rice and 50 g of duckweed; (Sb) 50g of broken rice and 50g of soya bean meal; and (Br) 50g of broken rice. The trial lasted 70 days.

The amounts of broken rice consumed by chickens in the station and farm locations were very similar: 42.7, 41.2 and 42.5 g/day (SE = 0.35) for the treatments Dw, Sb and Br, respectively on the station and 48 ,42 and 48 (SE = 0.23) for the same treatments in the farms in the village. The amounts of fresh duckweed eaten were: 35.8 ±0.35 and 49.4 ±0.22 g/day and of ground soya beans 26.6±0.35 and 28.1±0.22 g/day for station and farm, respectively. After adjusting by covariance for differences in initial weight the analysis for growth rate showed differences between supplements (P=0.001) and between locations (P=0.001) with an interaction between location and supplement (P=0.001).  Overall, the best growth was obtained with broken rice plus soya bean supplement and the worst with broken rice alone;  performance on the station was better than in the village.   In the station, soya bean supplemented chickens grew faster than those supplemented with duckweed; whereas on the farms, chickens supplemented with duckweed out-performed those given the ground soya bean. On both the station and the farm the margin of income over costs of birds and supplements was highest for the birds supplemented with broken rice and duckweed and lowest for those supplemented with broken rice and ground soya beans

Key words: Lemnaceae, chickens, fattening, supplementation, protein, broken rice,  preferences, choice feeding

Gas production from pig manure fed at different loading rates to
polyethylene tubular biodigesters

Bui Xuan An and T R Preston

University of Agriculture & Forestry, ThuDuc, HoChiMinh City, Vietnam;


Pig manure was fed at different loading rates (0.66, 1.33, 2, 2.66 kg dry matter/m³digester liquid volume/day) to four plug-flow plastic tube biodigesters of 1.5 m³ liquid volume. The design was a 4*4 Latin square arrangement. The hydraulic retention time was 30 days and each experimental period was 8 weeks, the first 7 weeks for adaptation to the chosen loading rate and the last week for measurements. The temperature in the digester varied from 25.3 to 27.3oC and loading concentrations were 2, 4, 6, 8% of dry matter in the constant daily liquid imput of 50 litres. The gas and methane yields increased linearly with increase in the  loading rate (P<0.001) but the efficiency or gas production (gas or methane production per unit of manure dry matter loaded into the digester) was highest with  the 2 kg DM / m³ loading rate. The temperature of the effluent was higher than in the input material (P<0.05) but inlet and effluent temperature, and pH of inlet and effluent were not affected by loading rate.

Key words: Polyethylene tube digester, loading rate, pig manure, biogas, methane


Comparison of the in sacco rumen and washing loss methods to estimate the potential energetic value of leaves from
tropical trees, shrubs and crop residues

Nguyen Van Lai and Nguyen Thi Thu Huong

Finca Ecologica, University of Tropical Agriculture
College of Agriculture and Forestry, National University of Ho Chi Minh City, Vietnam


Samples of leaves from ten tropical species: six trees (Acacia mangium, Acacia auriculiformis,Gliricidia sepium, Leucaena leucocephala, Indigofera teysamii, Jackfruit - Artocarpus heterophyllus), three crop plants (Cassava - Manihot esculenta, sugar cane - Saccharum officinarum, banana - Musacea)  and a crop residue (Rice straw - Oryza sativa) were put in nylon bags and the losses of dry matter were estimated for washing times of 30, 60, 90 and 120 minutes in a commercial semi-automatic washing machine, and incubation times of 6, 12, 24 and 48 hours in the rumen of a cow fed rice straw and fresh grass (Panicum maximum).

The relationships between losses of dry matter in the washing machine and time of washing were curvilinear (range of R² from 0.86 to 0.99) for all leaves except those from banana and Acacia auriculiformis where the relationship was linear (R²=0.99).  There were close relationships between in sacco dry matter loss after 48 hours incubation and dry matter losses by washing (R²=0.73, 0.80, 0.86 and 0.80 for washing times of 30, 60, 90 and 120 minutes [average values for all samples at each time were used in this analysis]). Selecting the 90 minute washing time and correlating the data obtained with this method (range 15-47% for the ten species) with those from the 48 hour in sacco dry matter loss (range 25-61%) gave an R² of 0.86. The two methods ranked the species similarly and were considered to be equally effective in rating the chosen materials as potential sources of digestible dry matter for both ruminant and monogastric livestock. The use of the washing loss method is recommended as a first approximation to estimation of nutritive value as it is simple, rapid, and low cost, and dispenses with the need for surgically modified animals. 

Key words: Washing losses, nutritive value, leaves, trees, crop residues, in sacco, analytical methods


Observations on scavenging Local (indigenous) and Tam Hoang (exotic) chickens given free access (when confined at night) to duckweed (Lemnaceae) offered alone or mixed with rice bran

Lylian Rodriguez and T R Preston

University of Tropical Agriculture, Campus of College of Agriculture and Forestry,
Thu duc District, Ho Chi Minh city, Vietnam;


Eight chickens at point of lay, four of one of the indigenous ecotypes typically used in Vietnam and four of an exotic strain imported orginally from China (the Tam Hoang), scavenged during the day in an integrated  farm (planted with cassava, bananas and forage trees with recycling of wastes from pigs and chickens through biodigesters and ponds for duckweed and fish). In the late afternoon until the following morning the chickens were confined individually in bamboo cages with free access to rice bran, fresh duckweed and a 50:50 mixture (fresh weight basis) of the two offered in separate feeders. After a period of 8 weeks of adaptation to the cages and to the scavenging system, records were kept daily during a period of 13 days.

There were major differences (P=0.001) between ecotypes in intake of duckweed offered as a single feed but not (P=0.18) when it was mixed with rice bran. As a consequence, total intake of duckweed (that offered separately plus that in the mixture) was almost twice as high (P=0.001) for the local chickens (65 g/day)  compared with the "exotic" Tam Hoang (38 g/day). Calculated levels of crude protein in the total diet dry matter were similar for both ecotypes  (15.9 and 15.2%) but the proportion of the protein derived from duckweed was almost 50% higher (20 versus 14%) for the local birds compared with  the exotics.

Key words: Scavenging, indigenous chickens, duckweed, feed intake, feed selection, ecotypes, rural poultry


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