Data/hora: 22/06/2024 07:21:09

Biblioteca(s): | Embrapa Pantanal.
Data corrente: | 07/08/1995
Data da última atualização: | 07/08/1995
Autoria: | REYNOLDS, E. B.; JONES, J. M.; JONES, J. H.; FUDGE, J. F.; KLEBERG JUNIOR, R. J.
Título: | Methods of supplying phosphorus to range cattle in South Texas.
Ano de publicação: | 1953
Fonte/Imprenta: | Texas Agricultural Experiment Station, n.773, p.3-16, 1953.
Idioma: | Inglês

Conteúdo:

An experiment was conducted on the Encino division of the King ranch near Falfurrias from 1941 to 1946 to determine the most practical methods of supplying phosphorus to range cattle and to determine the effect of applications of different phosphates on the yield and chemical composition of pasture forage. Phosphorus was supplied to cattle by feeding bonemeal in self-feeders, by adding disodium phosphate to a controlled water supply and by fertilizing pasture with triple superphosphate. Supplying phosphorus by all three methods
gave good results and prevented phosphorus deficiency in normal seasons. The specific application of these findings, however, may be somewhat different, depending on the circumstances. For example, some ranchmen will find it feasible to supply phosphorus in a controlled water system. Others may find it more paraticable to supply phosphorus supplements in self-feeders. Still others may prefer to supply phosphorus through pasture
fertilization. The results show conclusively, that the cattle will get the necessary phosphorus where any of these methods is used. Cows that were fed phosphorus supplements and cows on fertilized pasture produced larger calf crops and heavier calves
at weaning time than cpws that did not receive phosphorus supplements. The cows that did not receive phosphorus supplements produced 93 pounds of weaned calves per acre; 
cows that were fed bonemeal, 116 pounds; cows that received disodium phosphate in drinking water, 143 pounds; and cows on fertilized pasture, 176 pounds. Cows that did not
receive a phosphorus supplement yielded a gross return of $13.91 per acre for the 4 years.
After deducting the cost of phosphorus supplements or fertilizer, the cows that were fed bonemeal gave a return of $16.91 per acre; cows that received disodium phosphate in water, $20.39; and cows on fertilized pasture, $19.97. Feeding phosphorus supplements also greatly increased the amount of inorganic phosphorus in the blood stream. Supplying
phosphorus in self-feeders and in a controlled water systems, in general, maintained a 
slightly higher level of blood phosphorus than pasture fertilization. Pasture fertilization,
however, maintained an adequate phosphorus level in the blood stream except during the prolonged drough in 1945 and 1946. If pasture fertilization is used, it probably will be necessary to reduce the rate of stocking and feed phosphorus supplements during drough
to supply adequate phosphorus to the cattle. This system of management will utilize all the advantages of pasture fertilization and, at the same time, provide suficient phosphorus for cattle at all times. Applications of triple superphosphate, calcium metaphosphate, potassium metaphosphate and fused tricalcium phosphate increased the yield and phosphoric acid content of pasture forage. The increases in yield ranged from 33 to 84 percent, depending on the rate of application. Pound for pound of phosphoric acid, all the phosphates used apparently had about the same fertilizing value. In general, the phosphoric acid content of the grasses increased as the rate of phosphate application was increased. The heavier applications of triple superphosphate doubled the phosphoric acid content of the grasses and provided adequate phosphorus for range catle in normal seasons. The application of phosphates apparently did not affect the protein content of grasses. The applicaion of approximately 200 pounds of 48 percent triple superphosphate
per acre in 1941 was effective in increasing the yield and phosphorus content of pasture forage for 4 or 5 years. This amount of phosphate was profitable and is recommended where ranchmen can use it to advantage.

Palavras-Chave: | Fertilizacao; Fertilization; Pasture; Range catle; South Texas.
Thesagro: | Fósforo; Gado; Nutrição; Pastagem.
Thesaurus Nal: | nutrition; phosphorus.
Categoria do assunto: | --
Registro original: | Embrapa Pantanal (CPAP)
Exemplares: | CPAP - (29004-1) - ADD - SP - -- - SP0701 -  - 0701 - DIS