Rilke Tadeu Fonseca de Freitas

Parâmetros genéticos de longevidade e produtividade de fêmeas da raça Nelore

In order to estimate the (co)variance components, heritabilities and genetic correlations of longevity and herd life in females, informations of 56,413 births of females from a Nellore cattle herd, from 1950 to 2000, under different rearing and management conditions, were used. It was studied from calf: weaning weight (W205C), yearling weight (W365C), weight in 550 days (W550C), from cows: weaning weight (W205), yearling weight (W365) and weight in 550 days (W550), age at first calving (AFC), calving interval (CI), herd life (RL), longevity (LONG), reproductive efficiency (RE), index production (IP), index of metabolic production (IMP), sum of index production (SIP), sum of index metabolic production (SIMP). The analysis were performed using the MTDFREML software, estimating (co)variance components, assuming animal model. Direct genetic, maternal and permanent environmental effects were analyzed. Fixed effects of farm, feeding program, rearing condition, birth calf year, birth calf season and calf sex, were also analyzed. Heritability estimates showed similar results among the different analyses, higher (0.24 to 0.75) for W205, W365, W550, W205C, W365C, W550C, IP, IMP, AFC, RL, LONG and lower (0 to 0.10) for RE, CI, SIP and SIMP. Some correlations between maternal genetic effect and the growth traits were negative. In general, estimates of genetic and phenotypic correlations among LONG and growth traits were negative, suggesting genetic antagonism between LONG and early maturity, between the LONG and reproductive and productive traits were positive, suggesting the significant effect of reproductive and productive traits on LONG.

Influência do tempo de coleta e metodologias sobre a digestibilidade e o valor energético de rações para aves

Em um ensaio de digestibilidade, avaliou-se o metodo de coleta total de excretas e o metodo do oxido cromico como indicador. Determinou-se a energia metabolizavel aparente corrigida pelo nitrogenio retido (EMAn) e os coeficientes de digestibilidade aparente da materia seca (CDAMS) de uma racao a base de milho e farelo de soja, contendo 19% de PB e 3.100 kcal de EM/kg. Foram utilizados 60 galos Leghorn, com peso de 2.350±105 g. Cada galo foi avaliado pelos dois metodos simultaneamente em periodos consecutivos. Utilizou-se um delineamento inteiramente casualizado, com parcelas subdivididas, para as duas metodologias avaliadas. Com o uso do oxido cromico, os tratamentos foram definidos em um arranjo fatorial 4x5 (quatro niveis de oxido cromico, 0,2; 0,4; 0,6 e 0,8%, e cinco tempos de coleta de excretas, 1 a 5 dias), totalizando 20 tratamentos na parcela (galo), em dois periodos consecutivos (subparcelas), com tres repeticoes por periodo. Na coleta total de excretas, os tratamentos foram definidos como cinco tempos de coleta (1 a 5 dias) na parcela e dois periodos consecutivos na subparcela, com 12 repeticoes por periodo. O uso dos periodos consecutivos de coleta nao afetou a EMAn nem o CDAMS. No metodo de coleta total, os valores de EMAn e CDAMS atingiram um plato acima de dois dias de coleta, comprovando que o tempo de coleta pode ser reduzido para tres dias sem comprometer os valores determinados. Os resultados indicaram interacao dos niveis de oxido cromico na racao e do tempo de coleta para os valores de EMAn e CDAMS. Concluiu-se que tres dias de coleta sao suficientes para determinar a EMAn e o CDAMS de racoes a base de milho e farelo de soja. Com tres dias de coleta e com o uso de 0,665% de oxido cromico na racao, foi possivel determinar valores semelhantes de EMAn e CDAMS nas duas metodologias.

Sucesso do resfriamento e congelamento de sêmen de pirapitinga Brycon nattereri

Cooling and freezing protocols of pirapitinga (Brycon nattereri) semen were evaluated using semen diluted in 154mM NaCl, 200mM NaCl, Saad or BTS™, and cooled for seven days. Sperm motility was daily evaluated. Five extenders (277mM glucose, 154mM NaCl, 200mM NaCl, Saad and BTS™) were combined with two cryoprotectants (DMSO - dimethyl sulphoxide and methylglycol) to produce 10 cryosolutions. Semen was diluted in each cryosolutions, aspirated into 0.5ml straws and frozen. Sperm motility was evaluated after thawing (60°C, 8 sec). Then, semen was frozen in straws with different volumes (0.25 and 0.5ml), and thawed under different water-bath temperatures (50° and 60°C). Higher sperm motility (48%) was observed when semen was cooled in BTS™ for seven days. Post-thawing sperm motility above 68% was observed when semen was frozen in 154mM NaCl-methylglycol, BTS™-methylglycol, 200mM NaCl-DMSO or Saad-DMSO. There was no difference on sperm motility when semen was frozen in 0.25 or 0.5ml straws and thawed in 50° or 60°C water-bath. Thus, pirapitinga semen can be successfully cooled in BTS™ for seven days or frozen in 154 mM NaCl-methylglycol, BTS™- methylglycol, 200mM NaCl-DMSO and Saad-DMSO.

Níveis de óleo e adição de complexo enzimático na ração de frangos de corte

Two experimental assays were carried out to evaluate the effect of the soybean oil and enzymatic complex addition in corn and soybean meal based diets on the broilers performance and nutrients digestibility. In the experiment 1, 960 broiler chickens, unsexed, received the treatments into 4 x 2 factorial scheme (four levels of soybean oil addition, 0; 2.5; 5.0 and 7.5%, with or without addition of a enzymatic complex with amylase, xylanase and protease) in four replicates of 30 chickens each, from 1 to 21 days of age. After the first phase, the broilers fed a standard diet until 42 days of age to evaluate a possible residual effect of the treatments on the performance from 22 to 42 days old. At the 21 days of age, 90 chickens (three male and two female of each replicate) were transfered to metabolism room (experiment 2), were the chickens received the same experimental diets to determination of the energetic values and dry matter and ether extract digestibility coefficients. The results shown no effect of the enzymatic complex addition nor interaction of the oil levels and enzyme supplementation on the broilers performance. The energetic value of the diets enhanced in 2.3% with the oil addition, without enzyme supplementation effect. The oil level of the 2.33% allowed a maximum digestibility of the ether extract. It was concluded that oil addition in the diet result in a better broilers performance and feed conversion reached the plateau in the 2.18% oil level.

Criopreservação do sêmen de curimba (Prochilodus lineatus) mediante adição de diferentes diluidores, ativadores e crioprotetores

Semen samples of five specimens of Prochilodus lineatus (Valencienes, 1847) were used to test the toxic and cryoprotectants effects of six solutions based on BTS (Beltsville Thawing Solution®) 4.5%: A - BTS 4.5% + Methanol 10%; B - BTS 4.5% + DMSO 10%; C - BTS 4.5% + KCl 0.072% + Methanol 10%; D - BTS 4.5% + KCl 0.072% + DMSO 10%; E - BTS 4.5% + KI 0.036% + Methanol 10% and F - BTS 4.5% + KI 0.036% + DMSO 10%). The effect of other three activator solutions (Distillated Water, NaHCO3 60 mM and NaHCO3 119 mM) on the rate and duration of sperm motility were also evaluated before and after freezing. No significant differences were observed among the cryoprotectant solutions. Sperm motility rates for P. lineatus were higher for semen activated by NaHCO3 60mM and NaHCO3 119mM, which propitiated the highest sperm motility duration.

Redução de proteína e fósforo em rações com fitase para frangos de corte no período de 1 a 21 dias de idade: desempenho e teores de minerais na cama

The trial was carried out to evaluate the performance and mineral levels in the litter of broilers from 1 to 21 days old, fed diets with low-crude protein (CP) and low available phosphorus (AP) supplemented with synthetic amino acids and phytase. A total of 1-d 1.500 male Cobb broiler chickens averaging initial weight of 42.5 g was allotted to floor pens as a complete randomized blocks design, with 3 x 3 + 1 factorial arrangement, being three levels of CP (15, 17 and 19%) and three levels of AP (0.25, 0.34, and 0.45%) and a control with expected nutritional requirements, according to Brazilian researchers recommendations, with six replicates of 25 broilers. In the diets with 0.25 and 0.34% of AP 500 FTU of phytase were added and the Ca levels decreased by 17%. Weight gain of the broilers fed diets with 15% of CP supplemented with synthetic amino acids in the three levels of AP + phytase and in the diet with 17% CP and 0,25% AP + phytase was lower than those fed the control diet. The feed intake of the broilers feeding low CP (15% ad 17%) and low AP (0,25%) + phytase was lower than those fed the control diet.. However, it was not observed any significant differences for feed conversion. The broilers fed diets with 17% and 19% of CP, with low AP (0.34%), supplemented with synthetic amino acids and phytase showed performance similar to those obtained with control diet. The CP and AP levels affected P, Ca, Zn, Cu ad K contents in litter, but did not affect N content. The mineral levels in the litter decreased when broilers were fed diet containing 17% CP and 0.34% of AP, supplemented with synthetic amino acids and phytase, except for the N content. The CP and AP levels may be reduced by 17 and 0,34% respectively, in the broilers diets in the initial phase (1 to 21 days old), with no effect on performance, since the diets are supplemented with synthetic amino acids and phytase. These levels of CP and AP resulted in decreasing environmental impact, due to the decreasing P, Ca, Cu, and Zn contents in the litter.

Efeito do uso de óleo na dieta sobre a lipogênese e o perfil lipídico de tilápias-do-nilo

A total of 35 males of Nile tilapia, averaging initial weight of 205 g, were maintained in five 250 L metabolism boxes to evaluate the lipid metabolism of Nile tilapias (Oreochromis niloticus). The experiment lasted 30 days, from October to November 2006. The treatments were: control diet plus olive oil; control diet plus corn oil; control diet plus soybean oil; control diet plus linseed oil; control diet plus fish oil. The experiment was in a completely randomized design with five treatments and seven replicates. The evaluated parameters were: fatty acid profile of the muscle tissue and hepatic activity of glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme (ME). The data were submitted to variance analysis and the means of the treatments were compared by Scott-Knotts test (5% of significance). The fish fed on a diet rich in polyunsaturated fatty acids presented increased contents of such fat acids in their lipid muscle composition. The hepatic activity of G6PD was superior to that of ME, being higher in the specimen fed rations containing olive, corn and soybean oil, thus, evidencing the highest lipid muscle deposition of these fish.

Ácidos graxos na carne de búfalos e bovinos castrados e inteiros

The objective of this experiment was to compare fat and cholesterol content, and fatty acids (FA) profile in Longissimus dorsi muscle of castrated and young bulls from Nellore (NE) and ½ Nellore x Sindi (NS) cattle and Mediterranean buffaloes. Eight animals (four castrated and four young bulls) per genetic group was used, with a total of 24 animals. A completely randomized experimental design in a 3 x 2 factorial arrangement (three genetic groups and two sexual conditions) was used. Animals were fed the same diet and were slaughtered at average live weight of 437.5 kg (± 3.4 kg). Buffaloes and ½ NS beef cattle showed smaller fat percentage in meat (10.8 and 12.5%, respectively) than NE beef cattle (15.4%), as well as young bulls animals (8.9%) as compared to castrated animals (16,8%). For cholesterol and monounsaturated FA there was no difference among genetic groups and sexual conditions. For polyunsaturated FA, buffaloes showed higher content (9.55%) than beef cattle (7.27 NE and 8.95% ½ NS), as well as young bulls animals (9.96%) as compared to castrated animals (7.21%). Buffaloes and NE beef catle showed higher saturated FA content, 42.7 and 42.1%, respectively, in relation to ½ NS beef catle (39.8%). Buffaloes and young bull animal meat showed smaller fat content and higher polyunsaturated FA, showing that could be better for human healthy.

Efeitos dos métodos de abate e sexo na composição centesimal, perfil de ácidos graxos e colesterol da carne de capivaras

The objective of this work was to evaluate the effects of two slaughter methods: traditional (TS) and head-shot (HS) and sex on the proximate composition, fatty acids (FA) profile and cholesterol content of capybara meat. Twenty animals (13 males (M) and 7 females (F)), weighting about 45.71kg, were slaughtered. In longissimus dorsi (LD) muscle were determined: moisture, crude fat, protein and ash. In semimembranosus (SM) muscle, were determined: cholesterol content for colorimetric method and fatty acids (FA) profile for gas chromatography. The LD muscle had values of: 75.87% of moisture, 1.37% of crude fat, 22.11% of crude protein, 1.09% of ash. There were significant differences (p<0.01) between lipid contents of M (1.75%) and F (0.98%). The FA in major concentration (%) were: C16:0 (29.57); C18:1w9 (27.87); C18:2w6 (19.19); C18:0 (6.57); C18:3w3 (4.97); C14:0 (3.64); C20:4w6 (3.45); C18:1w7 (3.31) and C16:1w7 (1.90). Ratio value of poliunsaturated FA to saturated FA was 0.82. The average values of w6 FA and w3 FA were 23.41 and 5.63%, respectively. The factors sex and slaughter method had no effect on poliunsaturated FA percentages and cholesterol content (28.11mg/100g). Capybara meat presented low total lipid content and high crude protein values and FA w6/w3 ratio considered nutritionally adequated.

Planos nutricionais com a utilização de aminoácidos e fitase para frangos de corte mantendo o conceito de proteína ideal nas dietas

This study was carried out to evaluate the performance and characteristics of carcass of broiler chickens fed diets with reduced levels of CP, available P (aP) and Ca, supplemented with phytase and amino acids. The growth phases evaluated were: Phase1, 1 - 21 days old, phase 2, 22 - 42 days old. A completely randomized design was used, with the treatments constituted of five nutritional plans (NP), with six replicates of 25 birds each. The nutritional plans were: NP1 - basal ration (21.4% CP - phase 1) + basal ration (19.3% CP - phase 2); NP2 = basal ration (phase 1) + ration with 18% CP (phase 2); NP3 = basal ration (phase 1) + ration with 16% CP (phase 2); NP4 = ration with 19% CP (phase 1) + ration with 16% CP (phase 2) and NP5 = ration with 17% CP (phase 1) + ration with 16% CP (phase 2). Except for basal ration, it was reduced the level of aP for 0.34% and 0.30% in the phases 1 an 2, respectively, and Ca to 0.80 and 0.70% in the phases 1 and 2, respectively , and in theses diets were added 500 FTU of phytase/ kg of ration. The NP4 and NP5 affected the bird performance. The bird fed NP2 and NP3 showed performance similar to those which was fed NP1, while birds that were fed PN4 and PN5 remained unchanged. The carcass and breast yield were not influenced by the nutritional plans. The birds fed basal diets in the two rearing phases (NP1) showed higher yield of thigh + drumstick. There was increase of the abdominal fat when the birds were fed NP3, 4 and 5. In conclusion, is possible to reduce the protein of the ration up to 16% in the phase 2, supplemented with phytase and amino acids, since the ration of the phase 1 be formulated with recommended nutritional levels.