Livestock Research for Rural Development

Volume 12, Number 2, 2000

Abstracts of papers in LRRD, Volume 12,
Number 2

Feeding donkeys

A A Aganga, M Letso and A O Aganga*

Department of Animal Science and Production, Botswana College of Agriculture
Private Bag 0027, Gaborone, Botswana.
*Department of Animal Health and Production, Ministry of Agriculture,
Private Bag 45, Lobatse, Botswana.

Feeding is an important aspect in the management of any farm animal. It requires knowledge of the feeding behaviour and nutrient requirements of animals for specific production functions, e.g. work. The objective when feeding donkeys should be to make judicious use of available feed during times of deficit. This may be achieved by using the body condition scores of the donkeys as feeding guides or, where available, appropriate nutrient requirement data may be used.

In most practical considerations, donkey feeding is not as routine a management practice as for other farm animals. This is perhaps an indication of the economic value attached to donkeys or confidence in their resourcefulness when it comes to finding their own feed.

Key words: Donkeys, management, nutrition

Nutritional evaluation of mulberry leaves
 as feeds for ruminants

J Yao, B Yan, X Q Wang and J X Liu

College of Animal Sciences, Zhejiang University (Huajiachi Campus), 
Hangzhou 310029, P.R.China or

The leaves from four mulberry (Morus alba) strains cultivated in China were sampled at three stages of maturity in spring and autumn, respectively. Their nutritional value was evaluated in terms of chemical composition, amino acid (AA) content and in vitro gas production (GP). Excepting one strain which was slightly inferior to other strains, there was no great difference in chemical composition between different strains regardless of season. There was little seasonal difference in content of crude protein (CP) and true protein (TP) of mulberry leaves. Average CP contents were 21.1 and 20.9 (% in DM), and TP accounted for 88.2 and 85.8% of CP in spring and autumn, respectively. Content of neutral detergent fiber (NDF) was higher in autumn (41.1%) than in spring (38.8%). Except for a few amino acids, no difference (P>0.05) was observed in AA contents among the four strains. Total and essential amino acids were 70.0 to 81.6 and 24.7 to 31.6% of the CP for spring leaves, and 75.6 to 78.0 and 29.0 to 30.8% of the CP for autumn leaves, respectively. Potential GP and organic matter digestibility estimated from GP were 43.3 to 52.2 ml and 65.6 to 71.3% for spring leaves, and  35.4 to 38.7 ml and 56.3 to 61.4% for autumn leaves, respectively, indicating that the nutritional value of spring leaves is superior to that in autumn. Chemical composition of mulberry leaves was influenced by stage of maturuty, though the extent of the effect was different between spring and autumn leaves. For spring leaves, content of CP and TP was superior at mid-stage to that  in early or late stage, whereas the CP content in autumn decreased significantly (P<0.05) with the stage of maturity. The NDF content increased with stage of maturity (P<0.05) regardless of season. Amino acids content, individual, essential, non-essential and total, tended to increase with the stage of maturity, though the differences were not significant (P>0.05). Parameters of in vitro GP showed a similar trend to the CP content, suggesting that the nutritional value of mulberry leaves was higher at mid-stage in spring and at early stage in autumn. From these results, it is inferred that mulberry leaves, with their high protein and low fibre content and their high digestibility, may be used as supplementary protein source for ruminants.

Key words: mulberry leaves, chemical composition, amino acids, in vitro gas production

Perceptions of livestock service delivery among smallholder dairy producers: case studies from Central Kenya

John Morton and Valentine Miheso*

Social Sciences Department, Natural Resources Institute, Central Avenue, 
Chatham Maritime, Kent ME4 4TB
* International Livestock Research Institute, Nairobi, Kenya
(Now of: Land O'Lakes, Nairobi, Kenya)

The article examines the perceptions held by smallholder dairy producers of the various livestock services delivered to them and the organisations that deliver them. In particular it examines perceptions of the dairy cooperatives, formerly part of the state marketing system and now liberalised, and of newer and less formal self-help groups. In Kiambu District, close to Nairobi and characterised by intensive production, there is a highly competitive market for milk, a high degree of reliance on purchased feed and fodder, and a competitive market for livestock services. Farmers are prepared to accept lower milk prices from cooperatives than they would get elsewhere, if the package includes: monthly payment which allows budgeting for livestock and other expenses and a degree of short-term credit to allow access to feed and AI. Farmers retain an affection for the idea of cooperatives, but feel poorly informed and unable to participate in the face of the size and bureaucracy of the cooperatives. In Ol-Kalou, further from Nairobi and characterised by semi-extensive production, Self-Help Groups have been successful so far in attracting farmers with a package that centres on collective contracting with private dairies (and Kenya Cooperative Creamery) with a minimum of physical handling and marketing, and of other services. In both cases it is difficult to separate producer evaluations of particular services from overall perceptions of ownership and governance of the service delivery organisation, and of the widely varying commercial alternatives available.

Key words: Marketing, milk, cooperatives, smallholder dairyhing, Kenya, 

Effects of feeding star grass (Cynodon plectostachyus) on growth and digestibility of nutrients in the domestic rabbit

R Ramchurn, Z B Dullull, A Ruggoo and J Raggoo

University of Mauritius, Reduit, Mauritius

Twelve, forty-five-days old, New Zealand White rabbits were allocated to two treatments and kept in separate cages. The first treatment (control) was ad libitum complete rabbit pellets and the second treatment ( SG) was a combination of Star grass ad libitum along with 50g/day of mash concentrate as supplement. There were no health problems during the experimental period. The parameters measured used were growth, feed conversion and apparent digestibilities of dry matter, organic matter, protein, neutral detergent fibre, cellulose, hemicellulose, lignin and energy.

Growth rate was higher (P=0.001) on the pelleted complete diet (17.2± 2.35 g/day) than on the Star grass and mash (7.7 ± 1.02) reflecting a 30% increase in dry matter intake.  Feed conversion also favoured the pelleted diet.  There were no differences (P>0.05) in dry matter and organic matter digestibility. Digestibility of protein and energy was higher for the Star grass diet  than for the control (P<0.05) but was lower (P<0.05) for all cell wall components. 

Keywords: Rabbits, Star grass, digestibility, growth, conversion


Tecnificación del sistema de producción ganadera de doble propósito en el trópico alto andino Colombiano : amamantamiento restringido

Adriana Roldán, Pablo Perdomo, Hugo Sánchez G and Miguel Ramírez N

Universidad Nacional, Sede Palmira. AA 237,  Palmira, Valle, Colombia

A comparison was made of the two production systems: restricted suckling (AR) and traditional management (AT), which is predominant in the Andean region in Colombia. Ten recently calved cows (Normandy breed) were allocated at random to the two treatments. In the AR system the calves were used to stimulate milk "letdown". The cows were then milked completely by hand after which the calves were allowed to suck all four quarters for a period of 15 minutes. Cow and calf were then separated, the calf being tethered in a "Kikuyo" (Pennisetum clandestinun) pasture with daily rotation of the area (defined by the length of the tether which was 2m).  A concentrate supplement was given in quantities increasing from 100 to 500 g/day with 100 g increments each month. In the traditional system, the calf was used to stimulate "letdown", only three quarters of the udder were milked, one quarter being left for thecalf. After milking the cow and calf went together to a communal pasture from 6.30am to 13.00pm, at which time the calves were separated and put together in a pasture of Kikuyo with free access to water and salt. 

There were no differences between treatments for: calves in gain in liveweight and withers height;  and for cows in interval from calving to first oestrous and body condition scores.  Saleable milk was increased by 52% for the AR treatment. The higher productivity of the AR treatment implies an opportunity to reduce the pressure on the native forest adding environmental as well as technical and economic benefits to use of the AR system.

Keywords: Restricted suckling, dual purpose, cattle, Andean tropics.


La pollinaza como fuente de fósforo para 
rumiantes en pastoreo

Víctor M Segura Correa, Justo A Tepal Chalé, Julián Carvajal Azcorra 
y Arturo F Castellanos Ruelas*

Campo Experimental Tizimín. Centro de Investigación Regional del Sureste.
Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias.
Secretaría de Agricultura y Desarrollo Rural. 
Apartado postal 35. Tizimín, Yucatán. México.
*Facultad de Ingeniería Química, Universidad Autónoma de Yucatán. 
Av. Juarez 421. Ciudad Industrial. CP 97288. Mérida, Yuc. México

Two experiments, each of 84 days duration, were carried out to evaluate poultry manure as a phosphorus (P) source for growing-finishing bovines grazing Guinea grass (Panicum maximum) during the rainy season in a tropical environment. Treatments were:
Negative control (NC):  Animals received a supplement with only 0.2% P; 
Positive control (PC):  Phosphoric acid (H3PO4) was added to the supplement to provide 1.0% P
Experimental treatment (PM): Poultry manure provided 1.0% P in the supplement. 
The supplements in treatments PC and PM had 1.2% total P.  
In experiment 1, 90 Zebu bulls received 1.0 kg of supplement/animal/day. In experiment 2, 30 bulls (mixed Zebu and crosses of Zebu with Bos taurus)  received 0.378 kg of supplement/animal/day. Results were analyzed by means of the least square method of analysis. A lineal model that included the effect of treatment on average daily gain (ADG) was used. In experiment 1, there was no effect of P supplementation on average daily gain which was 1.040 kg/d. In the second experiment, the effect of P supplementation was significant the daily liveweight gains being 0.720, 0.850 and 0.820 kg/d for treatments NC, PC and PM, respectively. It is concluded that poultry manure is a good and available P source for bovines.

Key words: Poultry manure, phosphorus, ruminants, tropical grazing system.


Genetic study of Santa Gertrudis cattle in Brazil

J B S Ferraz, J P Eler and P M T Ribeiro 

Animal Breeding Group, Department of Basic Sciences, Faculdade de Zootecnia e Engenharia de Alimentos da Universidade de São Paulo. 
PO Box 23, CEP - 13630-970 Pirassununga - SP, Brazil

The present study was carried out to determine genetic, phenotypic and environmental parameters and genetic trend of Santa Gertrudis cattle. The traits analyzed were birth weight (WB), 120 days weight (W120), weaning weight (WW), yearling weight (WY) and 18-month weight (W18). There were records of weights of 12,737 animals and pedigree information of 29,921 animals from ten generations with records. Average inbreeding level was not high (0.0395).  Heritability estimates for all traits were from moderate to low (WB = 0.16; W120 = 0.06; WW = 0.13; WY = 0.12; W18 = 0.12). The genetic trends were 0.0244 kg/year for WB, 0.0579 kg/year for W120, 0.134 kg/year for WW, 0.291 kg/year for WY and 0.406 kg/year for W18. 

Keywords: animal model, genetic parameters, genetic trends, Santa Gertrudis cattle


Choice of animal models for estimation of genetic parameters of reproductive, growth and slaughter traits of Californian and New Zealand rabbits raised under tropical conditions

J B S Ferraz and J P Eler

University of Sao Paulo/FZEA/ZAB, 
Cx. Postal 23, 13630-970, Pirassununga SP Brazil

In order to compare different animal models, the methodology of mixed models under animal models was used to predict (co)variance components of 23 traits related to reproduction traits of 1,456 litters and growth and slaughter traits of 3,845 Californian and New Zealand White rabbits raised in southeastern Brazil. The (co)variance components, obtained by four different models in single trait analysis, were used to estimate genetic parameters. The four animal models considered as random effects only the animal direct genetic effects (model 1), the animal direct and permanent effects of litters or common effects of does as permanent environment effects (model 2), the animal direct and maternal genetic effects, uncorrelated to each other, and permanent environmental effects (model 3), and as in model 3, but with correlated animal direct and maternal effects (model 4). All the models considered the fixed effects of contemporary groups, parity, sex and the covariates - level of inbreeding of litters or rabbits, and litter sizes, where these were applied. The models were compared based on likelihood test and the "best" model is proposed for each trait. Permanent environmental effects were important for all traits and should be considered in animal models that analyze reproductive, growth and slaughter traits of rabbits of these two breeds. The magnitude of the c² term varied from 0 to 0.39. Maternal genetic effects were not important for reproductive traits, but significantly affected growth and slaughter traits, and were more important for New Zealand White than for Californian rabbits. Maternal heritabilities varied from 0.03 to 0.14. As models 1, 2, 3 and 4 gave different estimates for genetic parameters, total heritabilities were calculated for all traits. Total heritabilities were low for reproductive traits (from 0 to 0.14), and moderate for growth (from 0.03 to 0.36) and slaughter traits (0.02 to 0.23). Although New Zealand White and Californian rabbits perform similarly, the results showed that the genetic parameters for these two breeds are different and should not be analyzed together. The models chosen for each trait serve as guides for proposition of animal models in single or multi trait analysis of rabbit data.

Key words: Rabbits, genetic parameters, New Zealand White, Californian

The effect of tropical ambient temperature on productive performance and grazing behaviour of sows kept in a outdoor system

R H Santos Ricalde and I  J Lean*

Facultad de Medicina Veterinaria y Zootecnia - UADY, Apartado Postal 4-116 Itzimna, C.P. 9700, Merida, Yucatan, Mexico.

* Wye College, University of London, Ashford, Kent, TN25 5AH, UK.

The effects of two ambient temperature regimes (Low, 19.0 to 33.0 C° vs High, 27.0 to 40.0 C°) on productive performance and grazing behaviour of sows kept in an outdoor system under tropical conditions was investigated in a completely randomised experiment with twelve replicates in each treatment.

Mean weight at weaning was higher (P<0.05) in sows kept in treatment Low (L) than in sows kept in treatment High (H). Similarly, sows in treatment L had a positive weight gain (P<0.05) and backfat gain (P<0.05) from farrowing to weaning and from mating to weaning in comparison to sows in treatment H. There was a  reduction (P<0.05) in milk fat and an increase (P<0.05) in milk ash and milk lactose in sows kept in treatment H in comparison to sows in treatment L. Sows in treatment H had a lower (P<0.05) feed intake during lactation than sows in treatment L. Sows in treatment H had lower values (P<0.05) for time spent grazing, grazing activity and distances walked during the day in comparison to sows in treatment L

The results obtained in this experiment suggest that there was a negative effect of extremely high ambient temperatures on feed intake of the lactating sows and consequently on their weight gain and backfat gain from farrowing to weaning. Also, the extremely high ambient temperatures reduced grazing activities of the pregnant sows and modified the maternal milk composition.

Key words: Sows, Outdoor system, grazing behaviour, productive performance, milk composition, ambient temperature.


Smallholder dairy cattle production in Xochimilco in the Southeast of Mexico City:
Effect of herdsmen on spatial behaviour
of  cattle during restricted grazing

J Vieyra, H Losada, R Soriano, 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. Iztapalapa. CP 09340. México DF

This study measured the space occupied, effective grazing time and displays of aggressive and sociable behaviour of a herd of dairy cattle in Xochimilco, a sub-urban zone of Mexico City during 4 hours of grazing per day, under the supervision of a different herdsman for each of four consecutive days. No significant differences in space or effective grazing time were found with the different herdsmen. Expressions of both aggressiveness and sociability were found to be greater on days 2 and  4 than 1 and 3. A positive correlation was found between aggressive and sociable acts, indicating that if there is an effect of the herdsman, this is on the animals' overall state of animation, rather than on producing one of the two types of behaviour. These behaviours were much less common than those found previously among stabled cattle in urban conditions. The low effective grazing times are discussed in terms of the preference of herdsmen for 'walker' cattle, and the quality of available pasture.

Key words: Urban agriculture, welfare, dairying

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