National Institute of Animal Husbandry, Hanoi, Vietnam
Twenty four crossbred F1 cows (Friesian x Local) with their newborn calves were used in an experiment to evaluate the effects of restricted suckling (RS) on growth rate of the calves and milk yield and reproductive rate of the cows compared to artificial rearing (AR). The animals were randomly divided into two groups: RS and AR according to calving date. Cows and calves in both groups were kept under the same conditions. Calves under AR treatment were removed from their dams 3 days after calving and fed milk from buckets. Calves under RS treatment were allowed to suckle their dams twice daily for 30 minutes after milking.
The average daily weight gain of the RS calves was higher (P<0.05) than that of AR calves (445 vs 422 g/day). Milk conversion per kilogram weight gain was 4.2 kg for RS calves and 4.7 kg for AR calves. Average total milk yield of RS cows was 15% higher (P<0.05) than that of AR cows (10.9 vs 9.5 kg/day). Saleable milk of RS cows was 20% higher (P<0.01) than that of AR cows (9.0 vs 7.5 kg/day). There was no difference in postpartum interval to first oestrus (111 days for RS cows and 108 days for AR cows). Twenty five percent of the cows in AR treatment had mastitis while no cases were observed in the RS cows.
Restricted suckling is considered to be a more appropriate system than calf removal and artificial rearing for managing cows and calves and can be recommended especially for small-scale farmers.
H Losada, J Vieyra, J Rivera, H Martínez, R Pealing, J Cortés and L Arias
Animal Production Systems Area. Department of Biology of
Reproduction. Division of Biological and Health Sciences, Universidad Autónoma
Metropolitana-Iztapalapa. Av. Michoacán y la Purisíma. Col. Vicentina. Iztapalpa. CP
09340. México DF
E-mail: hrlc@xanum.uam.mx
A study regarding the use of physical space and the social behaviour of cows was carried out in five stables in Iztapalapa, in order to evaluate animal welfare within the concept of sustainability. The distribution of space demonstrated that the living quarters occupied 20% of the total surface area, while the space per head of cattle was 9.6m. Aggressive behaviour (ie: fighting, pushing and bumping) prevailed over social behaviour (ie: licking), with average attitude values (times observed in the activity during period of 6 consecutive days) of 114 for aggressive behaviour and 56.0 for social behaviour. During the period of observation (6 days), aggressive behaviour consistently dominated over social behaviour. The results obtained from this study are discussed within the context of the need to redefine the concept of sustainablility within the limits imposed by the urban agriculture of the large metropolises and the competition for land.
University of Tropical Agriculture, Thu Duc, Thanh Pho Ho
Chi Minh, Vietnam
Crop residues consisting of the aerial part of cowpea (Vigna sinensis), groundnut (Arachis hypogea) or leaves of banana (Musa sapientum) and cassava (Manihot esculenta Crantz) were examined for washing losses (WL) of dry matter and in vitro gas production characteristics by comparing rumen fluid and fresh voided sow faeces as source of inoculum. Samples were used in the fresh state of after sun-drying. A washing time of 90 min appeared to be the more convenient time for determining WL values. On average, the sun-dried samples had 62.8% higher WL (P<0.001) than the fresh samples. A highly significant relationship (R2 = 0.70; P<0.001) was found between in vitro gas production over 96 hr from materials incubated with sow faeces and the same index obtained from cow rumen fluid as sources of inoculum. The washing effect had a minor influence (P<0.05) on the in vitro potential gas production (a + b) whereas the source of inoculum had no significant effect on the in vitro rate constant "c" of gas production. The type of crop residue significantly influenced (P<0.001) both the value of potential gas production and the rate at which it is produced.
It is suggested that inocula prepared either from cow rumen fluid or freshly voided sow faeces can be used for a rapid screening of the degradation characteristics of a relatively large amount of unknown samples.
Agricultural College of Ho Chi Minh University, Ho Chi Minh city,
Vietnam
Leaves from twelve different trees and three agricultural crops, commonly available in the tropics were selected, dried and subjected to analysis by the in sacco nylon bag degradability test, the in vitro gas production test and the Kjeldahl test for nitrogen.
The protein content of the leaves was negatively related with the proportion of leaves in the harvested fresh foliage ((r = -0.63). The relative ranking of the feeds was similar when evaluated by the in vitro and in sacco methods after 24 or 48h incubation, and was in line with practical observations on the relative value of these feeds for goats. The exception was the sugar cane bagasse (pressed cane stalk after extraction of 2/3 the juice in an artisan crusher) which had a higher gas production than the best of the tree leaves (Cassava, gliricidia and I.teysamii) but a lower in sacco degradability. A similar situation prevailed in the case of the sugar cane leaves which were rated relatively higher by the in vitro gas test tnan the in sacco degradability method. The ranking of the feeds using the sum of the coefficients "a" + "b" (the total potential degradability) derived from the equation p=a+b(1-e-ct) in the in sacco rumen degradability test was broadly similar (r = 0.56) to the ranking by the 24h dry matter loss. The "c" coefficient was not related (r = 0.16) to the 24h dry matter loss nor to the practical assessment of the nutritive value of the feeds.
It is concluded that the in vitro gas production and in sacco rumen degradability techniques appear to be less useful in predicting nutritive value of tropical feeds than has been reported for temperate country feeds.
Goat and Rabbit Centre, Hatay, Vietnam
The leaves from two trees - Trichantera gigantea and Artocarpus heterophyllus (Jackfruit) - were used as the basal diet of growing goat kids. The only supplement was a multi-nutrient block containing molasses, urea and minerals. The leaves and the block were fed ad libitum and refusals recorded daily. There were 6 goats in individual cages on each treatment. The design was a single changeover with periods of 21 days on each of the rwo treatmenst. The apparent dry matter digestibility was measured during the last 7 days of the second period by total collection of faeces.
Jackfruit leaves had a higher dry matter content (36%) than leaves of T. gigantea (11%).The intake of fresh leaves was 29% higher for the jackfruit diet compared with T. gigantea. On a dry matter basis the intake was 270% higher for jackfruit (50g DM/kg LWt) than for T. gigantea (9.8 g DM/kg LWt). Kids fed T. gigantea lost 70 g/day of liveweight; in contrast, the weight gain on jackfruit leaves was 70 g/day. Apparent dry matter digestibility was higher on the jackfruit diet (66%) than on T. gigantea (48%).
It is concluded that the leaves of the jackfruit tree have a high nutritive value for growing goats.
CIPAV - COLCIENCIAS, Colombia
E-mail: cipav@cali.cetcol.net.co
The potential advantages of establishing mixtures of fodder tree species on farms when developing new feeding systems have been described in this paper. However, researchers still need to develop a series of principles from which recommendations can be developed. Since animal production in the tropics is facing new challenges, especially trying to balance food security and conservation goals, these principles need to relate to animal productivity, the productivity of the farming system as a whole and the maintenance of biodiversity.
The development of feeding systems based on mixtures which make better use of available resources and enable farmers to meet their objectives requires further research to address the questions listed above, preferably with the application of lateral thinking! Analysis of a mix of field observations and scientific experiment will help to establish principles and lead to recommendations which can be adapted by extension workers and farmers to a range of ecosystems and economic climates.
CIPAV-COLCIENCIAS (E-mail: cipav@cali.cetcol.net.co)
Trichanthera gigantea, a tree found in the Andean foothills of Colombia and in neighbouring countries of Central and South America adapts readily to a wide range of tropical ecosystems, and has been successfully introduced to Vietnam, Cambodia and the Philippines. It is easily established from cuttings and the leaves and green stems can be harvested some 8 to 9 months after planting and subsequently at intervals of two to four months giving an annual fresh biomass yield of about 60 tonnes/ha (containing about 10 tonnes of dry matter and 2 tonnes of protein). Data on its chemical composition and in vitro and in sacco fermentability indicate that it has potential as feed for livestock. However, in contrast to most tree foliages it appears to be more palatable to pigs and rabbits than to small ruminants.
Goat and Rabbit Research Centre, SonTay, Hatay, Vietnam
Three treatments were compared: planting at monthly intervals from June 1994 through to May 1995; mulching or no mulching with the dead leaves; and organic (cattle) manure or chemical fertilizer. The experimental design employed monthly planting as main plots, mulching or no mulching as split plots and fertilizer type as split-split plots.
This paper summarises results for the second harvest which was done 12 months after the first harvest. Fertilizer treatments and management were the same as in the first year. The two fertilizer regimes were: organic (from cattle) manure (20 tonnes/ha) or chemical fertilizers (150 N as urea, 100 P205, 200 K20 kg/ha) as control. Mulching consisted of detaching the dead leaves and leaving them on the soil surface or removing them from the plot at monthly intervals beginning 6 months after the previous harvest. The urea was given in three applications (at 1 month, 3 months and 5 months after first harvest). Phosphorus was supplied after harvest. Manure and potassium were in two dressings (75% after harvest and 25% 5 months later). The planting material was stem cuttings (30 cm length) in two continuous rows per furrow.
Overall populations decreased from the first to the second year. There was a strong indication (P=0.06) that the manure treatment supported a higher plant population than the chemical fertilizers. The yield of edible biomass (stalks, tops and green leaves) which can be used for feeding animals was higher in the second than in the first year, probably because of the better climatic conditions for plant growth. The pattern of yield was similar in both years with highest yields for plots established in the traditional season (January-July). Mulching increased yield by 8% in the first harvest and by 15% in the second harvest. It is concluded that year-round planting of sugar cane, although not recommended for sucrose prooduction, is nevertheless feasible when the crop is to be used as livestock feed.
Agricultural Research Institute, 1516 Nicosia, PO Box 2016, Cyprus
Email:miltos@arinet.ari.gov.cy
Eleven trials with growing Friesian heifers of different ages were carried out. In trials 1, 2 and 6, the voluntary intake of untreated (US) and urea-treated straw (UTS) was measured with Friesian heifers offered a constant allowance of a concentrate mixture. The effect of feeding a high (HP) or low protein (LP) concentrate mixture along with US or UTS, respectively was studied in four trials (trials 3, 9, 10 and 11). In another three trials (trials 4, 5 and 7), UTS offered with a LP content concentrate mixture was compared with US given along with a HP mixture provided by soybean meal (HP) or a combination of soybean meal and urea (LP+U). Finally, in trial 8 the effect of complete replacement of barley hay by UTS, both offered ad libitum, was studied over the period of 4-6 months of age.
UTS had greater crude protein (98 vs 43 g/kg DM) and in vitro digestibility (53.2 vs 44.9%) than US. Voluntary intake of UTS was greater by 3.2% (trial 1), 8.6% (trial 2) and 10% (trial 6) compared to US. There was no difference (trials 3, 6, 9, 10 and 11) in the performance of heifers on US and UTS fed along with a HP and LP mixture, respectively. With the exception of trial 5, there was an overall increase (12.4%) in weight gain of heifers on the urea-treated than the urea-supplemented diets. Finally, UTS successfully replaced barley hay (trial 8). Based on animal performance data, and the feeding costs obtained in the present studies, urea treatment expenses ranging from CYP 12.04 - 45.80 may be justified. It is concluded that under certain conditions urea treatment of straw is economically viable and treatment may enhance straw utilization.
Department of Animal Husbandry , Faulty of Agriculture, Cantho
University, Cantho city, Vietnam
Two pilot trials were carried out, in the period February to June 1996, to assess the feasibility of milking swamp buffaloes in villages in the Mekong delta, . Measurements were made of milk yield and composition and of the impact of the technology on the village society. The buffaloes selected for the trial were studied from the first to the fifth month of lactation. The calves sucked each teat for a few minutes and then two teats were milked by hand. Teats to be milked were rotated every two days. After milking the calf sucked the residual milk including the two teats milked out by hand. After sucking was finished, the calf was separated from the cow until the next milking. Daily milk yield was calculated as the yield from 4 teats by adding the mean of milk on days 1 and 2 (teats 1 and 2) with the mean of milk on days 3 and 4 (teats 3 and 4), and so on.
In trial 1, the average milk yield (meanSE) was 1.500.48 kg/day. The contents of fat and protein were 9.1 and 4.40%, respectively. In trial 2, the milk yield was 1.550.11 kg/day, and milk fat and protein were 8.68% and 4.86%, respectively. The period required to train the buffaloes for milking ranged from 15 to 32 days. The milk was readily consumed by children and old people. It is concluded that the milking of swamp buffaloes in villages in Vietnam has a promising potential to solve the problem of child malnutrition and to make more sustainable the farming systems.