Use of crossbreeding for increasing beef production in Tunisia

M Ben Salem and H Kélifa*

INRA Tunisia, Laboratory of Forage and Animal Productions, rue Hédi Karray, 2049 Ariana, Tunisia
lahmar.mondher@iresa.agrinet.tn
* Office of Livestock and Pasture, 30 rue Alain Savary, 1002 Tunis Belvédère, Tunisia

Abstract

Introduction

Almost half of the red meat production in Tunisia comes from cattle, with two thirds of that coming from fattened calves, whereas the remaing third is from cull cows (Tunisian Ministry of Agriculture 2008). In 2008, total domestic red meat production reached approximately 120.000 tonnes. However, such production level does not cover the population total need of red meat despite all the deployed efforts to improve animals’ productivity and to raise producer’s revenue. Previous studies and reports showed that growth performance of animals and profitability of feedlots remain low due to many constraints. Major limiting factors include the low nutritive values of common cereal forages, inadequate feeding management strategies and practices, and most importantly the lack of beef breeds. Indeed, like in most developing countries, beef production in Tunisia is carried out at the smallholder level where most feeding systems are based on locally available low quality cereal roughages, predominantly oat hay, and imported concentrate feeds. Moreover, cattle population in the country is composed of the native cow, imported dairy (Holstein-Friesian) and dual purpose (Brown Swiss and the Tarantaise) breeds, and their respective crossbreds, with the Holstein bred being by far the dominant one with more than 90% of the total herd. All these animals are primarily used to produce milk. They supply beef as a by-product when surplus calves and culled cows are slaughtered for meat. Local animals have a low aptitude for meat production. Reported data (Ben Dhia and Antic 1971; Rondia et al 1984; Atti and Ben Dhia 1987, 1990) showed average daily gains of only 750 g for local young bulls between the age of 3 and 12 months when raised under favorable conditions. The average gains for the Brown Swiss, the Tarantaise and the Holstein animals were 1036, 1016 and 1043 g/day, respectively.

Meanwhile, the continuous population increase and the improved revenue of households have served to emphasize the need for more beef production.  Efforts have been therefore directed towards the identification of appropriate crossing breeds for increased meat production. First, exotic dual purpose breeds such as the Brown Swiss and the Tarantaise were introduced to determine their possible use in crossbreeding with dairy animals. However, although some improvement was made in meat production, crossbreeding with these breeds still did not help in achieving the desired production and profitability levels. Thus a new crossbreeding program with beef breeds was recently implemented as an alternative to previous programs. The objective of this work is to evaluate, through field studies, the potential of using beef breeds, namely the White Blue Belgium (BBB) and the Charolais (CH), in crossbreeding programs with local animals for increasing beef production in Tunisia as compared to the use of dual purpose breeds (Brown Swiss and Tarentaise).

Methodology 

Data used in this work were collected from field studies conducted within the regular follow up activities of the national crossbreeding program implemented in late 2000 by the Office of Livestock production and pasture (OEP). This program aimed  to improving beef production efficiency and carcass quality using crossbreeding of local animals and their crossbreds with dairy breeds with beef breeds. The project covered cattle producers in different parts of the country (North East, North West, and the Center). First, it consisted in identifying potential candidate beef producers to be involved in the program, then in supplying them with the appropriate semen for artificial insemination. Insemination was performed following the synchronization of the animals by qualified inseminators either from the private sector of from OEP. Genotypes used in the program were the Brown Swiss (BS) and the Tarantaise (T) as dual purpose breeds and the CH and the BBB as the beef breeds. For each farm, the appropriate crossbreeding genotype (CH or BBB) was chosen according to the body conditions of the cows so as to ease calving and avoid dystocia.

Data on breeding, birth weight (BW), calving ease, average daily gain (ADG) and carcass weight (CW) of crossbred animals were collected over a 6-year period (2000-2006) through regular visits and surveys, conducted in collaboration with the project team. A total of 24000 cows was included in the study, with a significant increase in the number of involved animals over time, which went from 1000 in 2000 to more than 13000 heads in 2006.

To evaluate the effect of crossbreeding with beef type breeds on major productions indices, representative samples from both groups, the local x dual purpose and the local by beef type crossbred animals, were used for data collection and comparisons. All animals were raised under the same feeding, management and housing conditions. Commonly used diets were mainly based on low quality cereal hays and/or silages and straw. They were supplemented with a commercial concentrate containing about 14 to 15% of crude protein. The crossbreeding type effects on birth weight, average daily gain, growing period, slaughter age, carcass weight, and carcass value were examined. Differences were then quantified.

Information on feeding, diets and management, feedlot conditions, calving ease, birth weight, animal behavior, and percentage of adult and calf deaths,  were collected from the participating producers who filled out the information sheets handed out to them at the start of the program as a part of the monitoring process.

Results and discussion  

All parameters were improved when using crossbreeding with beef breeds as compared to the use of either dairy or dual purpose animals (Table 1).

The carcass weight of the local*dual purpose breeds varied between 240 and 250 kg, whereas that of local*beef type (Charolais and BBB) ranged between 310 and 329 kg with the highest value being observed for the Local*Charolais crossbreds. That is an average increase of 77 kg (or about 30%). Such an improvement was achieved under similar management conditions. However, when compared to dual purpose animals, particularly to the Brown Swiss, local*beef type animals had similar carcass weights despite their higher meat potential. This suggests that the nutritional requirements of the latter animals were not met in terms of energy and protein. This is more likely true given the low nutritional values of forages in the basal diets and their inadequate protein supplementation. In addition, and given the higher dressing percentage of the beef type animals, the increase of 77 kg in the carcass weight can be considered quite important. This is not only because of the weight per se, but also the higher quality of the carcasses and the specific preferences of butchers and consumers for the meat of beef-type animals. In addition, one also has to consider the higher sale price of the meat from these animals. Indeed, the price per kg in the local market of the carcasses from the beef crosses was 0.5 TND higher than that from other animals, which amounted on average to an additional gain of about 400 TND (300US$) per carcass.

In terms, of average daily gains, crossbreeding with beef breeds resulted in higher daily gains under similar fattening conditions and at the same slaughter age. Overall results showed that crossbreeding with beef breeds had average daily gains of 950 g, against 700 to 800 g when crossbreeding with dual purpose breeds. That is an improvement of about 217g per head per day (29%). However, despite such improvement, the observed gains were quite low given the genetic potential of the animals. Higher values of 1000 g/head/day were reported for dual purpose animals when fed better quality forages (Lahmar et al 2005).

The birth weight for dual purpose crossbred animals was 37.5 kg whereas for beef crossbred animals it varied between 40 to 545 kg. That is an increase of 5 kg which confers to these animals a better growth start and a higher aptitude for fattening. Similar weights were reported for dual purpose animals. Such increases in birth weight did not result in any significant decrease in the percentage of calving ease (Table 1). This is probably the result of the adequate choice of cows to be used in the crossbreeding program; a choice which was primarily based on the body size, lactation number and health status.

Conclusions 

• Previous production programs dealing with beef development relied mainly on the use of dairy animals and to a lesser extent on dual purpose breeds. They focused on improving management practices in the feedlots.

  
  

• A limited number of previous genetic studies involved crossbreeding of dairy and dual purpose breeds with the native cattle. This led to a small improvement in meat production but it was considered that breeds better able to produce beef efficiently needed to be identified.

  
  

• Results from the present study showed that using the CH and the BBB beef breeds in crossbreeding programs with local animals, and/or their respective crossbreds with dairy breeds, improves birth weight, daily gain, carcass weight and carcass quality and market value.

  
  

• It is suggested that crossbreeding with beef breeds is a method which can be used in the country to reach a sustainable self-sufficiency in domestic beef while improving farmers’ revenue, particularly under the current economical conditions when production efficiency is needed more than ever before. However, for this strategy to be successful a significant improvement will still be needed in terms of the production of good quality silages and hays and forage diversification, so as to improve the nutritional density of the diets and enable beef-type animals and their crossbreds to achieve their genetic potential for meat production.

References 

Atti N and Ben Dhia M 1987 Performances des bovins croisés en Tunisie. Annales de l’INRAT, Volume. 60 Fascicule 13 pp:24

Atti N and Ben Dhia M 1990 Performances des bovins croisés en Tunisie. Amélioration génétique des bovins sous climat sud-méditérranéen. EAAP publication N°47 pp: 196-199.

Ben Dhia and Antic A 1971 Résultats préliminaires de croisement d’absorption des bovins de race locale. Séminaire sur l’élevage et la production de viande bovine. Tunis.

Lahmar M, Djemali M and Khémiri H 2005 Cattle production in the mountain regions of North West Tunisia: present situation and prospects for increased productivity. Proceedings of the international symposium “animal production and natural resources utilization in the Mediterranean mountain areas”. EAAP Publication N° 115. pp: 395-400.

Rondia G, Deker A, Jabari M and Antoine A 1984 Produire plus de grain et de lait en Afrique du Nord. Projet ferme modèle de Frétissa. Publication Agricoles N°5.

Tunisian Ministry of Agriculture 2008 The red meat sector in Tunisia.

Received 13 June 2009; Accepted 4 September 2009; Published 1 October 2009

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