Avaliação econômica de bezerros alimentados com colostro fermentado, associado ao óleo de soja e zeranol / Economic evaluation of calves fed fermented colostrum, associated with soybean oil and zeranol

Utilizaram-se 40 bezerros Holandês x Zebu com objetivo de avaliar a viabilidade econômica da utilização do colostro fermentado, do óleo de soja e do zeranol em bezerros entre o 15º e o 60º dia de vida. Diariamente, foram fornecidos 1,5kg de concentrado contendo 23 por cento de proteína bruta, feno de tifton (Cynodon dactylon) à vontade e três litros de leite ou colostro fermentado. Considerando as despesas de criação e as receitas geradas, verificou-se menor custo dos animais tratados com colostro fermentado. Esse resultado, associado ao bom desempenho obtido, demonstrou que o colostro fermentado é eficiente como substituto do leite para bezerros em fase de aleitamento, gerando maior lucratividade.

Influence of feeding different amounts of milk on performance, health, and absorption capability of baby calves.

The influence of feeding high milk on performance, health, and absorption capability of the small intestine was studied in Holstein calves (eight males and eight females). Animals were kept in outdoor hutches bedded with straw. Treatments consisted of two quantities of milk: 1) 4.1 kg of whole milk from 3 to 48 days of age when calves were weaned and 2) gradually increasing milk from 4.1 to 7.0 kg during the first 2 wk of treatment and feeding 7.6 kg per day thereafter until day 42. Milk was reduced gradually during the 7th wk. Intake of milk averaged 4.1 and 6.7 kg per animal per day. Commercial starter, alfalfa hay, and water were offered ad libitum to all calves. Higher milk resulted in larger weight gains (615 versus 538 g/day) and less starter intake. Total dry matter intake, feed efficiency, and scour scores were not different between treatments, but rectal temperatures were greater on high milk. Female calves fed high milk showed less xylose absorption and more days medicated than females fed less milk.

Performance and digestion by calves from limestone added to milk replacers containing soy protein concentrate.

Sixteen male Holstein calves were fed milk replacers containing milk protein or 50% of the protein from soy protein concentrate for study of limestone as a buffer in the small intestine. Experimental diets were: A) 19% of crude protein as milk protein; B) same as A but containing .8% limestone; C) 19% crude protein, 9.5% milk protein, and 9.5% soy protein; and D) same as C but containing .8% limestone. Milk replacers were reconstituted with water to 14% solids and fed at 8, 9, 10, 11, 12, and 12% body weight from 1 to 6 wk of age. Calves were fed twice daily, and clean fresh water was available at all times. Soy protein concentrate in the replacer resulted in 20% lower weight gains, lower dry matter and protein digestibilities. Apparent crude protein retention also was reduced, but intake of nutrients, feed efficiencies, fecal scores, and rectal temperatures were not different between protein sources. Limestone did not change any of these measurements. Xylose absorption tests at 3 and 6 wk of age showed differences from age but not treatment. Analysis of digesta from different sections of the gut of 6-wk-old calves sacrificed 6 h after feeding revealed that pH throughout the small intestine was above 6 for both proteins, which may explain the ineffectiveness of added limestone. Compared to milk protein, soy protein concentrate produced a lower pH in the large intestine and feces.

Enzymatic hydrolysate of fish, spray-dried fish solubles, and soybean protein concentrate in milk replacers for calves.

Holstein calves (120) were fed milk replacers as the only nutrients from 4 to 46 days of age. All milk replacers contained 20% crude protein and differed in protein source: 1) 100% milk protein; 2) 67% milk protein, 33% soybean protein concentrate; 3) 67% milk protein, 33% enzymatic hydrolysate of fish; 4) 67% milk protein, 16.5% soybean protein concentrate, 16.5% enzymatic hydrolysate of fish; 5) 67% milk protein, 16.5% soybean protein concentrate, 16.5% spray-dried fish solubles; 6) 67% milk protein, 24.75% soybean protein concentrate, 8.25% spray-dried fish solubles. Substitution up to 33% of dietary protein with soybean protein concentrate or combinations of soybean, enzymatic hydrolysate of fish, or spray-dried fish solubles produced 14% lower weight gains than all milk protein, but 33% replacement with enzymatic hydrolysate of fish produced 27% lower weight gains. Feed consumed per kilogram of gain was least for all milk, most for 33% fish hydrolysate, and intermediate for other rations. Scour scores did not differ between diets.