Author: James Niven Shaw
Publisher:
ISBN:
Category : Sheep
Languages : en
Pages : 19
Book Description
Studies of Parasites in Oregon Sheep on Irrigated Pasture
Author: James Niven Shaw
Publisher:
ISBN:
Category : Sheep
Languages : en
Pages : 19
Book Description
Publisher:
ISBN:
Category : Sheep
Languages : en
Pages : 19
Book Description
Studies of Parasites in Oregon Sheep on Irrigated Pastures
Author: James Niven Shaw
Publisher:
ISBN:
Category : Sheep
Languages : en
Pages : 14
Book Description
Publisher:
ISBN:
Category : Sheep
Languages : en
Pages : 14
Book Description
An Epidemiologic Study of the Seasonal Incidence of Nematode Parasites in Sheep on Irrigated Pastures in Central Oregon
Author: Susan Marie Matlock
Publisher:
ISBN:
Category : Sheep
Languages : en
Pages : 226
Book Description
The epidemiology of nematode infections in ewes and lambs on irrigated pastures was investigated during one reproductive cycle in a commercial operation in Central Oregon. Primary objectives were to determine the sources of parasitism, the effect on lamb weight gains, and the effectiveness of control procedures in minimizing the detrimental effects of parasitism. Methodology included fecal nematode egg counts, animal necropsies and the use of tracer lambs. The relationships between blood trace mineral levels, parasitism and suboptimal weight gain in lambs and calves were also examined. High pasture burdens of infective larvae were found in spring and early summer from overwintering larvae and in late summer from autoinfestation by ewes and lambs. Lamb weight gain from March until mid-July was 0.48 lb/head/day. From mid-July until September when the study terminated, lamb weight gain declined ( -0.03 to 0.28 lb/head/day). Parasite burdens were low to moderate early in the grazing period, but increased markedly during the mid-July to September period, despite monthly deworming of the flock. It appeared that parasite burdens, high summer temperatures and the lack of shade, and possibly low cobalt and selenium levels were responsible for the late summer decline in weight gain. Evaluation of control measures indicated that intensive deworming prior to parturition eliminated arrested or inhibited larvae in the ewes. The periparturient relaxation of resistance, however, permitted development of infective larvae acquired from the pre- and post-lambing pastures. Maturation of these larvae caused a marked rise in post-parturient egg per gram counts of the ewes with subsequent relatively high rates of pasture contamination. Monthly deworming of the flock was moderately effective in reducing parasite burdens and pasture contamination. Alternate grazing of pastures by cattle and sheep, and ad lib. feeding of phenothiazine in salt were not effective as control measures.
Publisher:
ISBN:
Category : Sheep
Languages : en
Pages : 226
Book Description
The epidemiology of nematode infections in ewes and lambs on irrigated pastures was investigated during one reproductive cycle in a commercial operation in Central Oregon. Primary objectives were to determine the sources of parasitism, the effect on lamb weight gains, and the effectiveness of control procedures in minimizing the detrimental effects of parasitism. Methodology included fecal nematode egg counts, animal necropsies and the use of tracer lambs. The relationships between blood trace mineral levels, parasitism and suboptimal weight gain in lambs and calves were also examined. High pasture burdens of infective larvae were found in spring and early summer from overwintering larvae and in late summer from autoinfestation by ewes and lambs. Lamb weight gain from March until mid-July was 0.48 lb/head/day. From mid-July until September when the study terminated, lamb weight gain declined ( -0.03 to 0.28 lb/head/day). Parasite burdens were low to moderate early in the grazing period, but increased markedly during the mid-July to September period, despite monthly deworming of the flock. It appeared that parasite burdens, high summer temperatures and the lack of shade, and possibly low cobalt and selenium levels were responsible for the late summer decline in weight gain. Evaluation of control measures indicated that intensive deworming prior to parturition eliminated arrested or inhibited larvae in the ewes. The periparturient relaxation of resistance, however, permitted development of infective larvae acquired from the pre- and post-lambing pastures. Maturation of these larvae caused a marked rise in post-parturient egg per gram counts of the ewes with subsequent relatively high rates of pasture contamination. Monthly deworming of the flock was moderately effective in reducing parasite burdens and pasture contamination. Alternate grazing of pastures by cattle and sheep, and ad lib. feeding of phenothiazine in salt were not effective as control measures.
Experiment Station Record
Author: U.S. Office of Experiment Stations
Publisher:
ISBN:
Category : Agricultural experiment stations
Languages : en
Pages : 1054
Book Description
Publisher:
ISBN:
Category : Agricultural experiment stations
Languages : en
Pages : 1054
Book Description
Experiment Station Record
Author: United States. Office of Experiment Stations
Publisher:
ISBN:
Category : Agricultural experiment stations
Languages : en
Pages : 1134
Book Description
Publisher:
ISBN:
Category : Agricultural experiment stations
Languages : en
Pages : 1134
Book Description
Internal Parasites of Sheep
Author: William C. Marquardt
Publisher:
ISBN:
Category : Sheep
Languages : en
Pages : 22
Book Description
Publisher:
ISBN:
Category : Sheep
Languages : en
Pages : 22
Book Description
Bibliographical Bulletin
Author:
Publisher:
ISBN:
Category : Agriculture
Languages : en
Pages : 830
Book Description
Publisher:
ISBN:
Category : Agriculture
Languages : en
Pages : 830
Book Description
Oregon State Monographs: Studies in Zoology
Author:
Publisher:
ISBN:
Category : Zoology
Languages : en
Pages : 186
Book Description
Publisher:
ISBN:
Category : Zoology
Languages : en
Pages : 186
Book Description
Index-catalogue of Medical and Veterinary Zoology
Author:
Publisher:
ISBN:
Category : Parasites
Languages : en
Pages : 330
Book Description
Publisher:
ISBN:
Category : Parasites
Languages : en
Pages : 330
Book Description
List of Bulletins of the Agricultural Experiment Stations for the Calendar Years 1941 and 1942
Author:
Publisher:
ISBN:
Category : Agricultural experiment stations
Languages : en
Pages : 76
Book Description
Publisher:
ISBN:
Category : Agricultural experiment stations
Languages : en
Pages : 76
Book Description