Suchergebnisse

This study aimed to evaluate the inclusion of crude glycerin in diets for Nellore heifers grazing on a Brachiaria brizantha pasture, during the dry season, on urine and plasma urea concentrations, feeding behavior, and microbial protein synthesis. Sixty Nellore heifers with an average initial weight of 285.89 ± 18.74 kg, at approximately 19 ± 2 months of age, were distributed, in a completely randomized design, into the following five treatments with twelve replicates: 0.00, 4.00, 8.00, 12.00, and 16.00% inclusion of crude glycerin in the diet they were fed. Grazing time decreased linearly (P < 0.05) by 7.44 min with every percent of crude glycerin included in the diet. Microbial efficiency was not affected (P > 0.05), averaging 113.73g CP per kg TDN ingested. Plasma nitrogen concentration did not show any effects (P > 0.05), averaging 13.11 mg dL?1. Supplementing heifers during the dry season, at 0.7% BW, using up to 16% crude glycerin in the diet composition, did not elicit positive responses from feeding behavior and had little influence on microbial synthesis.

This study evaluated the feeding behavior of lactating cows on pasture of Brachiaria (Urochloa) decumbens fed with concentrate supplementation containing different levels of castor meal inclusion treated with calcium hydroxide Ca (OH) 2, in the proportions of 0; 3.3; 6.6 to 10% of the total diet. Eight cows (degree of blood ½ to ¾ Holstein x Zebu), with previous average production of 3000-4000 kg adjusted to 300 days of lactation and average body weight of 465.16 kg ± 65.45 kg were distributed in two 4 x 4 Latin squares. The behavior was assessed every five minutes for 24 hours on the 21st day of each period. The results were tested by analysis of variance and regression at p < 0.05 probability. The time spent in grazing, rumination, idle and in the trough; total chewing time, number of cuds per day, chewing per day; chewing per cud; the number of periods of grazing, rumination, idle and in the trough; time spent by period of grazing, rumination, idle and in the trough were not different between treatments. The feed efficiency (g DM h-1; g NDFa h-1 and g TDN h-1) and time spent per cud ruminated TSR sec cud-1) were linearly reduced. It is recommended to include up to 10% castor meal treated with Ca (OH)2 in the total diet.

To evaluate the fatty acid profile of milk from cows fed palm kernel cake (PKC), 12 Holstein × Zebu crossbred cows were kept in the feedlot, distributed into a triple 4 × 4 Latin square, and fed the following treatments: 1) control; 2) inclusion of 50 g PKC/kg in the total dry matter (TDM); 3) inclusion of 100 g PKC/kg in the TDM; and 4) inclusion of 150 g PKC/kg in the TDM. Milk samples from the morning and afternoon milkings were collected in the amount of 1% of the daily production of each animal; subsequently, 100-mL subsamples were frozen for analysis of the fatty acid profile. Inclusion of PKC did not change the concentration of short-chain fatty acids or myristoleic (C14:1), pentadecenoic (C15:1), palmitic (C16:0), and palmitoleic (C16:1) fatty acids. Concentrations of medium-chain and lauric (C12:0) and myristic (C14:0) fatty acids increased linearly (P &lt; 0.05). A decreasing linear effect was observed (P &lt; 0.05) on the concentration of the C15:0 fatty acid. No effects were observed (P &gt; 0.05) on the long-chain fatty acids and those of the omega 6 and 3 series; on the ratio between poly-unsaturated and saturated fatty acids; or on the ratio between the fatty acids of the omega 6/omega 3 series. The concentration of conjugated linoleic acid was not influenced (P &gt; 0.05) by inclusion of PKC in the diet. Addition of palm kernel cake to the diet of lactating cows influences the concentration of medium-chain fatty acids, and of lauric (C12:0), myristic (C14:0), and pentadecanoic (C15:0) fatty acids in their milk.