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Registro Completo |
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Biblioteca(s): |
Embrapa Pantanal. |
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Data corrente: |
07/02/1996 |
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Data da última atualização: |
10/10/2013 |
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Autoria: |
WILLIAMS, J. C.; KNOX, J. W. |
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Título: |
Effect of nematodes parasite infection on the performance of stocker cattle at hight stocking rates on Coastal bermudagrass pastures. |
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Ano de publicação: |
1976 |
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Fonte/Imprenta: |
American Journal of Veterinary Research, v.37, n.4, p.453-464, Apr. 1976. |
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Idioma: |
Inglês |
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Conteúdo: |
Studiews were conducted during the summer of 2 successive years (1971 and 1972) to determine the effects of gastrointestinal nematode parasitism on performance failure of stocker beef steers grazed at high stocking rates on Coastal bermudagrass pastures. During each of the 2 years, 3 groups of steers were rotated at 7- to 10-day intervals on sets of three 1.63-ha pastures from mid-May to late October. (Each group was maintained on a given set of pastures). In the 1971 program, from mid-May to early August (phase 1) each group consisted of 48 steers for a stocking rate of 29.6 steers/ha. From early August to late October (phase 2) the number of steers per group was reduced to 36 (stocking rate of 22.2 steers/ha) to improve the plane of nutrition. In the 1972 program, 2 groups were stocked at 48 steers per group (29.6 steers/ha) and a 3rd group was temporarily stocked with 58 steers (10 additional steers) to provide 2 animals each month for necropsy evaluation of worm burdens. With exception of the monthly removal of 2 steers from the 3rd group, the stocking rate in 1972 remained intact for the entire grazing season. In 1971, the 3 groups (groups 1, 2, and 3) were treated with thiabendazole (2 doses, 16 days between doses) before grazing. Parasite burdens and levels of pasture contamination were low initially and body weight gains were good during the 1st 3 months of grazing (phase 1). In the 2nd half (phase 2) of the grazing program, 1 group of steers given free-choice supplemental feed (1% of body weight/steer each day) and treated with anthelmintic (thiabendazole; 2 doses, 18 days between doses, during August) and another group, given supplemental feed only, had significantly better weight gains than did the 3rd group, not given supplemental feed nor treated with anthelmintic. There was no weight gain advantage derived from the reduced stocking rate in phase 2. Tracer calves, which were allowed to graze on pastures, developed an increased level of infection after August. Fecal egg counts in the principal steers and recovery of infective larvae from pasture paralleled the infection level in tracer calves. Necropsy evaluation of steers from groups 1, 2, and 3 at the end of the 1971 program indicated a similarity in total worm counts, but in the group not given supplemental feed nor treated with anthelmintic there was more generalized inflammation and a greater number of lesions in the abomasum (ostertagia) and the caudal portion of the intestine (Oesophagostomum). Steers in the 3rd group also were in poorer condition. Initial worm burdens in the 3 steer groups (groups 4, 5, and 6) were low at the start of the 1972 program. One group was given freechoice supplemental feed (0.5% of body weight/steer each day) and treated with anthelmintics (thiabendazole in the 1st dose levamisole in the 2nd dose, 12 days between doses, in May and August) and another group was given supplemental feed throughout the summer; the 3rd group was treated with anthelminthics (in May and August). The groups given supplemental feed had significantly greater weight gains than did the group not given supplemental feed (i.e., only treated with anthelmintics). Results of necropsies of steers each month from the group without supplemental feed revealed low worm burdens from June through September; however, the degree of inflamation and number of parasitic lesions in the abomasum and caudal part of the intestine increased after August. Necropsy evaluation of steers from groups 4, 5, and 6 at the end of the 1972 program indicated similarities in total worm burdens, but the 3rd gropu had more inflammation, more parasitic lesions, and greater unthriftiness.
Supplemental feeding did not improve weight gains during early months of grazing (1972), but was of value from August on. The combined effect of supplemental feed and anthelmintic was most effective in allowing good weight gains and minimizing the effects of parasitism. Use of anthelmintic alone was of little value in regard to growth response and minimizing effects of parasitism. With adequate to good control of the adverse effects of nematode parasitism by treatment with anthelmintics and giving supplemental feeding, it was apparent that the high stocking rate (29.6 steers/ha), coupled with a tendency of Coastal bermudagrass to have less nutrient quality during late summer, was responsible for failure to achieve projected weight gains in stocker steers. MenosStudiews were conducted during the summer of 2 successive years (1971 and 1972) to determine the effects of gastrointestinal nematode parasitism on performance failure of stocker beef steers grazed at high stocking rates on Coastal bermudagrass pastures. During each of the 2 years, 3 groups of steers were rotated at 7- to 10-day intervals on sets of three 1.63-ha pastures from mid-May to late October. (Each group was maintained on a given set of pastures). In the 1971 program, from mid-May to early August (phase 1) each group consisted of 48 steers for a stocking rate of 29.6 steers/ha. From early August to late October (phase 2) the number of steers per group was reduced to 36 (stocking rate of 22.2 steers/ha) to improve the plane of nutrition. In the 1972 program, 2 groups were stocked at 48 steers per group (29.6 steers/ha) and a 3rd group was temporarily stocked with 58 steers (10 additional steers) to provide 2 animals each month for necropsy evaluation of worm burdens. With exception of the monthly removal of 2 steers from the 3rd group, the stocking rate in 1972 remained intact for the entire grazing season. In 1971, the 3 groups (groups 1, 2, and 3) were treated with thiabendazole (2 doses, 16 days between doses) before grazing. Parasite burdens and levels of pasture contamination were low initially and body weight gains were good during the 1st 3 months of grazing (phase 1). In the 2nd half (phase 2) of the grazing program, 1 group of steers given free-choice supple... Mostrar Tudo |
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Palavras-Chave: |
Bermudagrass pasture; Nematode; Parasita; Parasite. |
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Thesagro: |
Gado; Infecção; Nematóide; Pastagem. |
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Thesaurus Nal: |
cattle; infection. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 05175naa a2200253 a 4500
001 1787125
005 2013-10-10
008 1976 bl --- 0-- u #d
100 1 $aWILLIAMS, J. C.
245 $aEffect of nematodes parasite infection on the performance of stocker cattle at hight stocking rates on Coastal bermudagrass pastures.
260 $c1976
520 $aStudiews were conducted during the summer of 2 successive years (1971 and 1972) to determine the effects of gastrointestinal nematode parasitism on performance failure of stocker beef steers grazed at high stocking rates on Coastal bermudagrass pastures. During each of the 2 years, 3 groups of steers were rotated at 7- to 10-day intervals on sets of three 1.63-ha pastures from mid-May to late October. (Each group was maintained on a given set of pastures). In the 1971 program, from mid-May to early August (phase 1) each group consisted of 48 steers for a stocking rate of 29.6 steers/ha. From early August to late October (phase 2) the number of steers per group was reduced to 36 (stocking rate of 22.2 steers/ha) to improve the plane of nutrition. In the 1972 program, 2 groups were stocked at 48 steers per group (29.6 steers/ha) and a 3rd group was temporarily stocked with 58 steers (10 additional steers) to provide 2 animals each month for necropsy evaluation of worm burdens. With exception of the monthly removal of 2 steers from the 3rd group, the stocking rate in 1972 remained intact for the entire grazing season. In 1971, the 3 groups (groups 1, 2, and 3) were treated with thiabendazole (2 doses, 16 days between doses) before grazing. Parasite burdens and levels of pasture contamination were low initially and body weight gains were good during the 1st 3 months of grazing (phase 1). In the 2nd half (phase 2) of the grazing program, 1 group of steers given free-choice supplemental feed (1% of body weight/steer each day) and treated with anthelmintic (thiabendazole; 2 doses, 18 days between doses, during August) and another group, given supplemental feed only, had significantly better weight gains than did the 3rd group, not given supplemental feed nor treated with anthelmintic. There was no weight gain advantage derived from the reduced stocking rate in phase 2. Tracer calves, which were allowed to graze on pastures, developed an increased level of infection after August. Fecal egg counts in the principal steers and recovery of infective larvae from pasture paralleled the infection level in tracer calves. Necropsy evaluation of steers from groups 1, 2, and 3 at the end of the 1971 program indicated a similarity in total worm counts, but in the group not given supplemental feed nor treated with anthelmintic there was more generalized inflammation and a greater number of lesions in the abomasum (ostertagia) and the caudal portion of the intestine (Oesophagostomum). Steers in the 3rd group also were in poorer condition. Initial worm burdens in the 3 steer groups (groups 4, 5, and 6) were low at the start of the 1972 program. One group was given freechoice supplemental feed (0.5% of body weight/steer each day) and treated with anthelmintics (thiabendazole in the 1st dose levamisole in the 2nd dose, 12 days between doses, in May and August) and another group was given supplemental feed throughout the summer; the 3rd group was treated with anthelminthics (in May and August). The groups given supplemental feed had significantly greater weight gains than did the group not given supplemental feed (i.e., only treated with anthelmintics). Results of necropsies of steers each month from the group without supplemental feed revealed low worm burdens from June through September; however, the degree of inflamation and number of parasitic lesions in the abomasum and caudal part of the intestine increased after August. Necropsy evaluation of steers from groups 4, 5, and 6 at the end of the 1972 program indicated similarities in total worm burdens, but the 3rd gropu had more inflammation, more parasitic lesions, and greater unthriftiness. Supplemental feeding did not improve weight gains during early months of grazing (1972), but was of value from August on. The combined effect of supplemental feed and anthelmintic was most effective in allowing good weight gains and minimizing the effects of parasitism. Use of anthelmintic alone was of little value in regard to growth response and minimizing effects of parasitism. With adequate to good control of the adverse effects of nematode parasitism by treatment with anthelmintics and giving supplemental feeding, it was apparent that the high stocking rate (29.6 steers/ha), coupled with a tendency of Coastal bermudagrass to have less nutrient quality during late summer, was responsible for failure to achieve projected weight gains in stocker steers.
650 $acattle
650 $ainfection
650 $aGado
650 $aInfecção
650 $aNematóide
650 $aPastagem
653 $aBermudagrass pasture
653 $aNematode
653 $aParasita
653 $aParasite
700 1 $aKNOX, J. W.
773 $tAmerican Journal of Veterinary Research$gv.37, n.4, p.453-464, Apr. 1976.
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Registro original: |
Embrapa Pantanal (CPAP) |
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