Jair de Araújo Marques

Evaluation of cassava and its industrial residues in replacement of corn on performance of feedlot heifers

The objective of this work was to study the replacement of corn by cassava hulls, swept cassava meal or cassava scrapings on the average weight gain, feed intake, feed:gain ratio and carcass yields of feedlot heifers. Twenty-eight crossbreeding heifers averaging 365 kg LW and 24 months of age were allotted to a randomized blocks design in a 56 days experimental period, with four diets and seven replicates. There was no effect of replacement of corn by cassava products on average weight gain, feed:gain ratio and carcass yields. However, feed intake was smaller in the diets with cassava scrapings and by-product cassava.

Recuperação Fecal de Indicadores Internos Avaliados em Ruminantes

This experiment was carried out to assess the fecal recuperation of the following internal markers: acid insoluble ash (AIA), acid detergent insoluble ash (ADIA), indigestible acid detergent fiber (IADF), indigestible neutral detergent fiber (INDF), and the apparent digestibility of dry matter (DM) and organic matter (OM). Four castrated sheep were used, fed with four levels of substitution of corn by cassava by-product meal. The feed samples, orts and feces were incubated in situ for 192 hours in three Holstein cows with ruminal cannula to determine the indigestible neutral detergent fiber and indigestible acid detergent fiber. The fecal recuperation of AIA and INDF were not different from 100% and had values for the digestibility coefficient of DM and OM similar to those obtained by the total feces collection method. The fecal recuperation of ADIA and IADF differed from 100%.

Glycerine levels in the diets of crossbred bulls finished in feedlot: carcass characteristics and meat quality.

The effects of corn replacement by different glycerine levels on carcass characteristics and meat quality of 40 young Purunã bulls, weighing 209 ± 33.3 kg and 8 ± 0.9 months old, finished in feedlot, were evaluated. The treatments were G00: without glycerine; G06: 6% glycerine; G12: 12% glycerine; and G18: 18% glycerine in the diets, on a DM basis. Hot weight, dressing, conformation and length carcass, leg length and cushion thickness were not (P>0.05) modified by different glycerine levels in the diets. Glycerine in the diets did not (P>0.05) affect fat thickness, Longissimus muscle area, marbling and texture. Muscle, fat and bone percentages were not (P>0.05) influenced by glycerine levels in the diets. No changes (P>0.05) in lightness (L*), redness (a*) and yellowness (b*) on LM occurred when glycerine was included at 0, 6, 12 or 18% in the diet. There was no (P>0.05) difference in LM moisture, ash, crude protein and total lipids when feeding different glycerine levels. The inclusion of glycerine decreased (P<0.01) total saturated (10.8%), and increased monounsaturated (7.4%) and poly-unsaturated (44.0%) fatty acids, which resulted in a higher PUFA:SFA ratio (0.57).

Desempenho de novilhas alimentadas com rações contendo milho ou casca de mandioca como fonte energética e farelo de algodão ou levedura como fonte protéica

ABSTRACT - The effect of the combination of energy sources (corn or cassava hull) and protein sources (cottonseed meal or yeast + meat and bone meal) in four diets, using corn silage as forage source, on the performance and intake of DM, CP, OM, ME, ADF, NDF, starch, Ca and P, using heifers. The effect of the addition salt or mineralized salt was also evaluated. A total of 28 heifers with average 303 kg LW and 18 months of age, confined during 76 days, was used. There were differences on nutrients intake among diets, however, there was no effect of the sources of energy, protein and salt on the average daily gain, carcass yield and feed:gain ratio. Therefore, yeast could substitute cottonseed meal as protein source, so as cassava hull could replace corn as energy source, without affecting the performance of feedlot heifers. The calcium intake by the heifers was higher in the mineralized salt diets as compared to salt diets.

Substituição do milho pela farinha de varredura de mandioca (Manihot esculenta Crantz) em rações de ovinos: consumo, digestibilidade, balanços de nitrogênio e energia e parâmetros ruminais

This work was carried-out to study the effect of substitution levels of corn (COR) by cassava by-product flour (CPF) (25, 50, 75 and 100%) in the ration for sheep on voluntary intake, nutrients apparent digestibility and nitrogen (NB) and energy (EB) balance, pH and ammonia concentration (N-NH3) in ruminal liquid. Four male, castrated sheep, without defined race, with medium weight of 41.4 AW, in trial of digestibility were used, using the method of total collect feces and urine. The animals were kept in cages of metabolism in 4x4 latin square design. The ruminal liquid was obtained by means of probe esofagic in the times 0, 2, 4, 6 and 8 hours (after feeding). There was no effect of substitution levels on intake of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), energy and nitrogen (N) and for apparent digestibility of DM, OM, CP, NDF, starch and gross energy (GE) and for NB and TDN levels. The intake of starch and GE presented quadratic increase until the level of 75% CPM in the ration. The concentration of the ammonia nitrogen and the pH of ruminal liquid did not differ in function of the substitution levels of the COR to CPM. It was concluded that CPM can totally substitute COR in the sheep ration.

Características físico-químicas da carcaça e da carne de novilhas submetidas ao anestro cirúrgico ou mecânico terminadas em confinamento

This study was conducted to evaluate the effect of pregnancy simulation (placement of 100 lead spheres in the uterus-LEAD) and ovariectomy (OVAE) on traits of carcass and meat of heifers finished in feedlot. Animals not pregnant and with intact ovary were used as the control (CTRL). Nineteen crossbred heifers (½ Nelore x ½ Red Angus) averaging 18 months of age and 257.8 kg of body weight were used. Animals were fed a diet containing (% DM): 41% of corn silage and 59% of soybean meal, corn, and trace minerals. No significant differences were observed for slaughter weight, which averaged 324.1, 323.3, and 303.3 kg, respectively, for CTRL, LEAD, and OVAE treatments. Similarly, there were no significant differences among treatments for the following variables: hot carcass weight (171.1 kg), carcass length (113.8 cm), hind limb length (68.2 cm), cushion thickness (21.0 cm), loin eye area (57.3 cm2), fat thickness (4.0 mm), percentages of muscle (62.6%), bone (16.0%), and fat (21.7%), muscle/fat ratio (3.9), muscle plus fat/bone ratio (5.3), cooking losses (24.3%), freezing to cooking losses (30.9%), tenderness (7.1 points), juiciness (6.6 points), and flavor (6.6 points). The color, texture, and marbling parameters also did not differ averaging 4.0, 4.4, and 3.7 points, respectively, among treatments. In addition, no significant differences were found to contents of ash (1.1%), crude protein (21.8%), total fat (2.9%), and cholesterol (49.6mg/100g) in the Longissimus dorsi muscle. Thus, it can be concluded that estrus did not affect carcass characteristics.

Desempenho e características de carcaça de tourinhos mestiços terminados em confinamento com dietas à base de cana-de-açúcar em substituição à silagem de sorgo

The experiment was conducted to evaluate the use of sugar cane at two concentrate levels as a replacement for sorghum silage in the diet of crossbred young bulls in feedlot. Thirty-six young crossbred males were maintained in individual stalls in a randomized complete experimental design with three diets: sorghum silage with 1.0% of the live weight (LW) in concentrate, sugar cane with concentrate (1.0% LW) and sugar cane with concentrate (1.2% LW). The diets were calculated to have approximately 12% crude protein. The diets did not cause differences in the dressing percentage, feed conversion and bone, muscle and fat percentage. The daily gains and bio-nutritional index were higher for the animals fed with sorghum silage (1.70 kg and 13.12, respectively). The final weight and ingestions of dry matter, crude protein, neutral detergent fiber and total digestible nutrients were higher for the animals fed sorghum silage. The replacement of sorghum silage with sugar cane reduce the animal performance, even when a higher level of concentrate is supplied in the diet.

Avaliação da substituição do milho pelo resíduo seco da extração da fécula de mandioca sobre o desempenho de novilhas mestiças em confinamento

The objective of this trial was to evaluate the total replacement of corn with a dry residue extracted from cassava starch on production of crossbred heifers in feedlot. Thirty crossbred heifers averaging 21 months of age and 325 kg of body weight were distributed in two experimental groups and then housed in two stalls. Both groups were submitted to a pre-trial period of 49 days, in which animals received ad libitum sorghum silage and 1.05% of body weight as concentrate (19.67% CP) composed of soybean meal, corn, and urea. In this period, daily weigh gain (DWG) averaged 1.08 kg for both groups. The experimental period lasted 57 days with animals averaging 378 kg of body weight. At the beginning of the experimental period, one group remained receiving the pre-trial diet while the other was fed ad libitum sorghum silage and 1.18% of body weight as concentrate (18.12% CP) containing dry cassava byproduct rather than corn. Daily weight gain was significantly higher for heifers fed corn-based concentrate (0.97 kg) compared to those receiving dry cassava byproduct-based concentrate (0.78 kg). In addition, dry matter intake and feed conversion were both lower on heifers fed the diet containing dry cassava byproduct.

Behavior of beef cattle in silvipastoral systems with eucalyptus.

It was aimed to verify the effect of the presence of trees and their heights in silvipastoral system on the intake behavior of Nellore heifers in the summer. Ten heifers for the following systems were used: system without shade, silvipastoral system with 8-meter and 18-meter trees. The data were collected in three days during 12 hours, subdivided in morning (7:15 a.m. to 1. p.m.) and afternoon (1:15 p.m. to 7 p.m.). It was evaluated the times and frequency of grazing, rumination, idle and the percentage of time that the animals remained in the shade; black globe-humidity index, whose average and minimum values (86 and 82) were equal for 8-meter tree system and 18-meter tree system; however they were lower when compared to the without shade system (89 and 86). There was an interaction between the systems and the periods for all the analyzed variables, except for the rumination frequency. For system without shade, the grazing time did not differ between morning (202 min) and afternoon (187 min); however the grazing frequency was lower for the afternoon (3.17). For 8-meter trees systems and 18 meter trees system, the grazing time in the afternoon, respectively, with 195.50 and 219.00 min was higher than in the morning, respectively, with 128.00 and 158.50 minutes. The rumination time was higher in the morning for all systems. The grazing frequency for 8-meter trees was 3.58, for the without shade system it was 3.05 and for 18-meter tree system it was 2.22. A higher idle time and the idle frequency was found in system without shade (97.50 min and 3.80 respectively) in the afternoon. For 8-meter tree system (98.50 min and 4.47 respectively) and 18-meter tree system (127.00 min and 4.27 respectively), they were higher in the morning. The animals remained under shade for an average of 43.49% (with trees with 8 m) and 49.81% (with trees with 18 m) of the time. It was concluded that the presence of trees modify the time and the frequency in grazing and idle; however, it does not influence the time and frequency in rumination.

Comportamento e eficiência ingestiva de tourinhos mestiços confinados com três dietas diferentes

To study the ingestive behavior of 36 young crossbred bulls in feedlot, 3 diets were evaluated: sorghum silage plus concentrate at 1.0% of the live weight, sugar cane plus concentrate at 1.0% or 1.2% of the live weight. The experimental period was of 100 days after 15 days for animal adaptation. The data were recorded during 24 h, divided in 4 intervals of observation, at 20, 35, 50 and 65 days after the beginning of the confinement with analysis of the time series every 15 minutes. Duration and frequency of feeding, rumination and idle, dry matter and neutral detergent fiber intake, feeding and rumination efficiency of dry matter and neutral detergent fiber and total chewing time, were evaluated. There were no significant differences (p>0.05) among the treatments for duration of feeding, rumination and idle, being the feeding efficiency higher for the animals fed with diets based on sorghum silage. The rumination efficiency did not differ between diets with sorghum silage and sugar cane with 1.2% of the concentrate. The feed intake was higher from 06:15 to 18:00 h and the animals spent more time ruminating (144.75±19.55 min) from 00:15 to 06:00 h. The duration of feeding and rumination are not a good indication of the real intake.