Influence of climatic factors on the development of pneumonia in lambs

https://doi.org/10.1016/j.smallrumres.2008.08.004Get rights and content

Abstract

Pneumonia is responsible for important economical losses in the sheep industry in Spain and many other sheep-rearing countries, being the main cause of lamb death, and of losses due to condemnations in abattoirs and of drug costs. This respiratory syndrome is a complex disease involving the relationship between host and environment. The present study analyses the influence of environmental factors on the development of pneumonia in lambs. Statistically significant correlations were found between pneumonia as a cause of lamb death and climatic factors such as rainfall, humidity and intensity and direction of wind. The type of farm building was also an important factor to take into account in order to improve the prevention of pneumonia in lambs. Moreover, the age of the lambs was seen to be a significant item in the study of pneumonia. Respiratory pathology increased from 23 days of age. This fact permits the implementation of measures from birth to 23 days with a view to reducing pneumonia and its negative influence on lamb production. The paper discusses the practical implications of these findings for sheep production.

Introduction

Respiratory problems are common and relevant diseases of sheep in all the major sheep-rearing countries. They cause mortality in lambs, reduced growth and an important economic impact in drug costs and condemnations in abattoirs (Jones et al., 1982, Moreno, 1994, Cano et al., 1995, Goodwin et al., 2004). Lamb pneumonia is regarded as a complex disease, involving interaction among host, (immunological and physiological), multiple agents, (bacterial, viral, mycoplasma) and environmental factors (Brodgen et al., 1998). There is a lack of epidemiological surveys, although, in some studies, the abattoir pathology data have been used to evaluate the influence of environmental factors on the pneumonia (McIlroy et al., 1989, Moreno, 1994, Luzon, 1999). How the design of the animal installations impact the economy of the sheep flocks is one of the questions farmers frequently ask. In this report, we summarise an investigation into mortality rates in lambs with special reference to the influence of the climate factor in the development of pneumonia in lambs on four farms in Aragon, a traditional lamb producing area located in the northeast of Spain.

Section snippets

Materials and methods

This study was performed on four farms producing young lambs for meat. In this area, lambs are slaughtered when their live weight is between 21 and 25 kg (2–3 months old). The farmers follow a traditional husbandry system, housing sheep in the farm buildings towards the end of pregnancy, just 1 month before birth. Most of them were managed under accelerated lambing, such as the Cornell STAR system. In this husbandry system they carry out 3–5 lambing periods per year and 1.5–1.9 lambs are sold

Results

The evaluation of the causes of death in this study showed pneumonia to be the second most frequent cause (28.7%), preceded by deaths due to digestive disorders (29.2%). These two causes were followed by starvation (22.9%). Respiratory and digestive processes varied according to the year and the flock studied, but, on all the farms, there was a remarkable increase of pneumonic pathology in the year 2003. Dramatic climatic differences were recorded in 2003 compared to the two previous years.

Discussion

The lamb mortality rates due to respiratory problems obtained in this study were similar to others previously registered in the same type of lamb product and in the same geographic region (Luzon, 1999). However, in the present study, we have observed the mortality causes in more detail from birth to slaughter according to age. Thus, we observed that there were variations during the life of the animal and this fact may have important consequences in the analysis of the impact of respiratory

Acknowledgements

The authors thank to the farmers: J. Oliva, V. Oliva, J. Bravo and J. Sanz for allowing us to use their farms for this study.

References (25)

  • S.H. Binns et al.

    Risk factors for lamb mortality on UK sheep farms

    Prev. Vet. Med.

    (2002)
  • S. Chandrasekaran et al.

    Evaluation of combined Pasteurella vaccines in control of sheep pneumonia

    Br. Vet. J.

    (1991)
  • M.L. Nash et al.

    Risk factors for respiratory disease mortality in lambs

    Small Rumin. Res.

    (1997)
  • P. Ábalos

    Epidemiología y nuevas estrategias de control de los procesos respiratorios en rumiantes

    Albeitar

    (marzo 2006)
  • K.A. Brodgen et al.

    Pasteurella haemolytica complicated respiratory infections in sheep and goats

    Vet. Res.

    (1998)
  • Cano, T., Hervás, J., Padró, J.M., 1995. Estudio epizooetiológico y clínico de los procesos respiratorios en corderos...
  • De Las Heras Guillamon, M., 2001. Las Pasteurellas en la patología respiratoria ovina. Simposium Satélite sobre...
  • K.S. Diker et al.

    Antimicrobial susceptibility of Pasteurella haemolytica and Pasteurella multocida isolated from pneumonic ovine lungs

    Vet. Rec.

    (1994)
  • C. Ewers et al.

    Mannheimia haemolytica and the pathogenesis of enzootic bronchopneumonia

    Berl. Munch Tierarztl. Wochenschr.

    (2004)
  • Ferrer Mayayo, L.M., 2001. Repercusión económica de la Pasteurelosis ovina. Tratamiento y Control. Simposium Satélite...
  • K.A. Goodwin et al.

    Pneumonic lesions in lambs in New Zeland: patterns of prevalence and effects on production

    N. Z. Vet. J.

    (2004)
  • E. Gracia Curras et al.

    Toma de muestras del respiratorio

    Albéitar

    (2005)
  • Cited by (0)

    View full text