José Henrique Souza da Silva

Óleo de citronela no controle do carrapato de bovinos

This research was aimed at evaluating in vitro and in vivo effects of citronella (Cymbopogon nardus (L.) Rendle) oil on catle ticks. The volatile oil was obtained from de fresh leaves of citronella grass by steam destilation and the yelds was 0.7%. Seven (0; 0.5; 1.0; 10.0; 25.0; 50.0; 100.0%) and nine (0.1; 0.25; 0.5; 1.0; 2.0; 10.0; 25.0; 50.0; 100.0%) concentrations of citonella oil were used on in vitro trials with engorged female ticks. The efficacy control ticks was 0; 44.2; 92.1; 85.6; 87.8; 87.0; 88.9 and 0; 0.7; 2.8; 51.6; 79.3; 81.0; 87.1; 86.7 89.5 %, respectively. These sugest that the citronella oil can be practical used for controlling of catle ticks.

DESENVOLVIMENTO E COMPOSIÇÃO CORPORAL DE ALEVINOS DE JUNDIÁ (Rhamdia quelen) ALIMENTADOS COM DIETAS CONTENDO DIFERENTES FONTES DE LIPÍDIOS

Three sources of lipids, canola oil (T1), cod liver oil (T2), and swine fat (T3), were tested in experimental rations for juveniles of jundia (Rhamdia quelen), representing 5% of their diet. A completely randomized design with three treatments (T) and three repetitions was used. The performance and the carcass yield were not affected by the three lipids. The lipids sources influenced the protein (high value on T1) and fat (high value on T3) deposition in the carcass.

Sistemas de alimentação na produção de cordeiros para abate aos 28 kg

The objective of this trial was to study the performance of ewes and lambs as well as the characteristics of carcass of lambs in different feeding systems. Eighteen lambs, 24 hours after birth, were randomly assigned with their mothers to one of the following treatments: RP - ryegrass (Lolium multiflorum) pasture; FNCP - feedlot with no creep feeding; and FCP - feedlot with creep feeding. The ryegrass pasture was managed in order to not limit the dry matter intake of the grazing animals with an average supply of 12 kg of dry matter per 100 kg of live weight. Animals on FNCP treatment received a diet containing 50% of sorghum silage + 50% of concentrate [11.5% crude protein (CP) and 64.4% of total digestible nutrients (TDN). Animals on FCP treatment received a diet containing 50% of sorghum silage + 25% of concentrate (8.2% CP and 60.6% TDN) and after they reached 21 days of age were fed an amount of concentrate (18% CP and 70% TDN) equal to 3% of the live weight. Average daily weight gains of 300 g/day and hot carcass yield greater than 51% were obtained by nursing lambs on either ryegrass pasture or feedlots. Data from the present trial showed no significant differences among treatments in production and carcass characteristics of lambs slaughtered with 28 kg of live weight.

Proporções e coeficientes de crescimento dos não-componentes da carcaça de cordeiros e cordeiras em diferentes métodos de alimentação

The experiment was carried out to study the components proportions, non-carcass of the body weight and their relative growth. It was used 45 lambs: 22 non-castrated male and 23 females of Texel breed. From that group, 7 were slaughtered in the beginning of the experiment and the others when they reached 25 or 33 kg. A randomly delineation adopted was by a factorial arrangement of 3:2:2 (three methods, two sexes and two weights of slaughter). The head and paws proportions decreased with elevation of the slaughter weight with values of 4.44% and 2.63% to 25 kg; 3.76% and 2.43% to 33 kg, respectively. Among sex, the main proportion of the kidney fat was reached 33 kg to females and among the weights of slaughter. The skin, liver and heart proportions did not distinguished among feeding methods, sexes and weights of slaughter. The large proportion of rumen and small net was for lambs weaned in 45 days, but between sexes and weights of slaughter was similar. The paws, heart, kidney, lung and trachea relative growth is premature, whereas to skin, liver and kidney fat is isometric, in relation to the weight of the empty body. The rumen+small net had premature growth regardless sex and feeding methods with coefficients ranging from 2.22 to 2.47.

Características quantitativas da carcaça de novilhos jovens e superjovens de diferentes grupos genéticos

The objective of this trial was to evaluate the carcass quantitative characteristics of two categories: steers and young steers, from two genetic groups, 5/8Charolais (CH) 3/8Nelore (NE) and 5/8NE 3/8CH, and to evaluate the relation among studied variables. The animals were fedlot finished until reaching 430 kg of body weight. Steers were slaughtered averaging 22.8 months old and young steers 15.2 months old. The diet, roughage:concentrate ratio of 60:40 (dry matter basis), contained 10.25% crude protein and 3.18 Mcal of digestible energy/kg of dry matter. The experiment was analyzed as a complete randomized design with six replicates, according to a 2 x 2 (two categories x two genetic groups) factorial scheme. Significant interactions were verified for hot (HDP) and cold (CDP) dressing percentage. 5/8NE 3/8CH young steers showed higher HDP (57.51 vs. 54.10%) and CDP (54.84 vs. 52.62%) than 5/8CH 3/8NE of same category and in relation to 5/8NE 3/8CH steers (55.43 vs. 53.84%, respectively).Young steers showed carcasses with higher subcutaneous fat thickness in mm (6.29 vs. 3.22) and mm/100 kg cold carcass weight (2.71 vs. 1.39), cushion thickness (26.58 vs. 25.17 cm), sidecut percentage (13.45 vs. 11.34) and lower sawcut percentage (50.33 vs. 51.39) than steers. Between genetic groups, 5/8CH 3/8NE animals showed carcasses with higher conformation score (11.00 vs. 10.33 points), and 5/8NE 3/8CH higher leg length (72.46 vs. 69.92 cm), arm length (41.92 vs. 38.46 cm) and forequarter percentage (37.54 vs. 36.43). Carcass conformation was positively correlated with Longissimus dorsi area (r = 0.35), cushion thickness (r = 0.23) and arm perimeter (r = 0.15), and negatively with chilling loss of carcass (r = - 0.35). The correlation coefficient was of 0.55 between subcutaneous fat thickness and sidecut percentage.

Desenvolvimento de bovinos de corte de diferentes grupos genéticos desmamados aos 3 ou 7 meses de idade

The objective of this experiment was to evaluate the performance up to 24 months of age of males from two breeding systems, straightbred (Charolais - C and Nellore - N) and crossbred (1/2 CN, 1/2 NC), submitted to two ages of weaning: T3-weaning at three months of age; T7-weaning at 7 months of age. The calves were maintained from birth to the weaning time with the cows on native pasture and, after weaning, both animals from T3 and T7 were maintained during a period of 30 days in a feedlot. The animals from T3, from 4 to 7 months, were maintained on pearl millet pasture (Pennisetum americanum). The weights at 3, 7, 12, 18 and 24 months of age and the average daily gain (ADG) among the different ages were collected. There was no interaction between the breeding system and genetic group within breeding system and age at weaning for the studied variables. The average daily gain of the T3 calves was lower from 3 to 7 months and higher from 7 to 12 months, afterward no difference was observed in the ADG. The only difference for weight was at 7 months, when T7 calves showed higher weight. The weight at 24 months was 424 and 423 kg, respectively, for T3 and T7. The crossbred animals showed higher ADG from 7 to 18 months and were heavier at 18 and 24 months. The heterosis for ADG ranged from .6 to 29.9%, and for weight at different ages ranged from -.68 to 12.41%. When the nutrition conditions are adequate, the weaning at 3 months does not affect slaughter weight at 24 months of age.

PRODUÇÃO ANIMAL EM VÁRZEA SISTEMATIZADA CULTIVADA COM FORRAGEIRAS DE ESTAÇÃO FRIA SUBMETIDAS A DIFERENTES NÍVEIS DE ADUBAÇÃO

The use of lowland areas in the Central Depression of Rio Grande do Sul State, Brazil is basically limited to irrigated rice. Those areas stay on fallow during the winter due to lack of a good natural drainage. Improvement in drainage can be obtained througth area leveling and microrelief correction associated to the establishment of superficial drains. Therefore, an experiment was conducted in order to evaluate cattle production on a leveled lowland area with several grazing winter plant species under different fertilizer rates. The experiment was conducted at the Federal University of Santa Maria in a soil of the Vacacai mapping unit. The area was leveled with a 0.06% slope gradient and the plant species were ryegrass (Lolium multiflorum), white clover (Trifolium repens) and birdsfoot trefoil (Lotus corniculatus). The fertilizer levels were 50%, 100% and 150% of the official recomended rate and the soil had its pH corrected to 5.5 using limestone. The experiment design was a randomized block with two replications and each experimental unit measured 0.5ha. The beef calves had 8-10 months of age and placed under continuous grazing, with 480 kg ha-1 of live weight for treatment. The parameters evaluated were: individual daily weight gain, animal load, weight gain per area, average dry matter accumulation by the pastures, in vitro digestibility, protein and botanical composition. The dry matter of the pastures was around 1000kg ha-1 and average accumulation for dry matter of the pastures was 19.9kg ha-1 day-1. The average weight gain per animal was 1016g animal-1 day--1, with an average load 738.6kg per hectare and the average weight gain was 469.7 kg ha-1. The total number of grazing days were 98, 121 and 128 for the 50, 100 and 150% recommended fertilizer rates. The NPK fertilizer levels, keeping constant the nitrogen fertilization, didn´t affect the average daily weight gain, animal load and weight gain per area.

Rendimentos de cortes da carcaça, características da carne e componentes do peso vivo em cordeiros terminados em três sistemas de alimentação

This study was carried outto evaluate the carcass physical composition, meat characteristics and the component conditions, non carcass live weight of lambs finished in different feeding systems. Sixteen lambs (Texel x Ile de France) were used and ramdomly allotted with their mothers, 24 hours after their birth, to three treatments: NSP - Natural supplemented pasture, RP - Ryegrass pasture (Lolium multiflorum lam.) and CON - Confinement. In relation to the cold carcass, there was no difference to the neck percentage among NSP, RP and CON, with values of 9.26, 9.20 and 9.30% respectively. The animals of NSP (33.68%) and CON (33.41%) showed similar and higher values than the RP (31.35%). The softness measured in the loin portion from the 9th to 11th ribs, by means of Warner Blatzler-Shear equipment, was of 8.6 for the confined animals, and this value was higher than those of NSP and RP animals (5.7 and 5.3, respectively). There were no treatment effectsfor the softness through the panel, tastiness and succulence. The skin percentage of RP animals (11.91) was higher than the percentage of NSP and CON animals (10.20 and 9.33%, respectively). Values of gastric content percentage were higher for CON animal s (13.62%)in relation to NSP animals (7.90%), and those ones higher than the RP animals (4.75%). The panel, as a method to determine tastiness, succulence and softness did not show difference in the lambs meat fed in natural supplemented pasture, ryegrass pasture and confinement.

Performance and economic evaluation of young finished feedlot bulls fed different concentrate levels in the diet

This study was conducted to evaluate the performance and economic viability of young bulls slaughtered at 14-16 months old, fed on different concentrate levels in the diet. Sixteen young bulls were randomly distributed and fed with 22, 40, 59 or 79% concentrate in the diet, resulting in four replications per treatment. The initial age and weight were 9.32 months and 192.44 kg, respectively. Final age, final weight, neutral fiber detergent intake, feed conversion and monthly profit decreased with increasing concentrate levels. The dry matter intake as percentage of live weight and metabolic size showed quadratic variation, increasing to 67 and 75% concentrate in the diet, respectively. The digestible energy intake and average daily weight gain increased with increases in concentrate levels. The increase in the level of dietary concentrate from 22 to 79% increased the animal performance, but decreased the profitability of young finished feedlot bulls at 14-16 months old.

Características das partes do corpo não-integrantes da carcaça de novilhos jovens e superjovens de diferentes grupos genéticos

The objective of this trial was to evaluate the components of non integrate body components of carcass of two categories, steers (slaughtered at 22.8 months old) and young steers (slaughtered at 15.2 months old), from two genetic groups, 5/8 Charolais (CH) 3/8 Nellore (NE) and 5/8NE 3/8CH, and to evaluate the relationship among the variables studied. The animals were fedlot finished until reaching 430 kg. The diet, roughage:concentrate ratio of 60:40 (dry matter basis), contained 10.25% crude protein and 3.18 Mcal of digestible energy/kg of dry matter. The experiment was analyzed as a complete randomized design with six replicates, according to a 2 x 2 (two categories x two genetic groups) factorial scheme. Slaughter weight (SW) and empty body weight (EBW) were similar between categories and between genetic groups. When the components were expressed as absolute values and adjusted for EBW and SW, steers showed higher heart, liver, empty omasum and total vital organs weights, and young steers showed higher rawhide, kidney fat, trim fat and total internal fats weights. While 5/8CH 3/8NE showed higher liver, kidney fat, total vital organs and blood weights, and 5/8NE 3/8CH higher rawhide and total external components weights. When adjusted for EBW, steers showed higher weights of components lung, empty rumen+reticulum and total empty digestible tract, while 5/8CH 3/8NE showed higher total empty digestible tract weight. Each kg of intermuscular fat deposited in the carcass represented increase of 0.006 points in slaughter body condition score, 0.113 mm in subcutaneous fat thickness, 0.253 kg in ruminal+visceral fat, 0.089 kg in kidney fat, 0.076 kg in trim fat and 0.040 kg in inguinal fat. Positive relation was verified among requirement of net energy for maintenance and weight of vital organs components.