Infestation with the sheep body louse (Bovicola ovis) in Merino lines divergently selected for maternal multiple rearing ability : short communication
Journal of the South African Veterinary Association
| Field | Value | |
| Title | Infestation with the sheep body louse (Bovicola ovis) in Merino lines divergently selected for maternal multiple rearing ability : short communication | |
| Creator | Cloete, S.W.P. Laubscher, J.M. Cloete, J.J.E. | |
| Description | Data were obtained from a population consisting of 160 Merino ewes, as well as 64 male and 75 female progeny of these ewes at the 2-tooth age. The age and sex groups were maintained in separate flocks. The population has been divergently selected from the same base since 1986, either for (high or H line) or against (low or L line) maternal multiple rearing ability. All animals were inspected for sheep lice (Bovicola ovis) during September / October 2002 after a wool growth period of at least 4 months. When expressed relative to mean L-line performance, the advantage in lambs weaned per ewe during the lambing season amounted to approximately 110 % in the H line (1.01 vs 0.48; P 0.01). The proportion of animals on which 1 or more lice were observed were markedly lower in 2-tooth replacement ewes than in replacement rams and mature breeding ewes (0.053 vs 0.625 and 0.531, respectively; P 0.01). One or more lice were observed on a lower proportion of H-line ewes than on those of the L line (0.413 vs 0.571, respectively; P 0.10), while a similar tendency was observed in 2-tooth ewe hoggets (0.033 vs 0.143, respectively; P =0.16). When the mean number of lice on individuals on which 1 or more lice were observed was compared between lines, the average number of lice observed on H-line young rams was lower than in the L line (4.36 ± 0.85 vs 9.71 ± 1.84 lice, respectively; P 0.01). A similar tendency was observed in mature breeding ewes (2.15 ± 0.38 vs 3.22 ± 0.42 lice, respectively; P 0.20). The more highly reproductive H-line ewes were not more susceptible to infestation with B. ovis than ewes of the L line. In fact, available evidence suggest that H-line animals could be more tolerant of B. ovis than those of the L line. | |
| Publisher | AOSIS | |
| Date | 2003-06-27 | |
| Identifier | 10.4102/jsava.v74i2.506 | |
| Source | Journal of the South African Veterinary Association; Vol 74, No 2 (2003); 57-59 2224-9435 1019-9128 | |
| Language | eng | |
| Relation |
The following web links (URLs) may trigger a file download or direct you to an alternative webpage to gain access to a publication file format of the published article:
https://jsava.co.za/index.php/jsava/article/view/506/488
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