RESUMO

This study aimed at evaluating the influence of dietary glutamine, glutamic acid and nucleotides on duodenal and jejunal carbon turnover, and on mucosa morphometry of piglets weaned at an age of 21 days. The diets were: additive-free diet - control (C); 1% of glutamine (G); 1% of glutamic acid (GA); and 1% of nucleotides (N). In intestinal mucosa morphometry trial, 65 animals were used. At day 0 (baseline), five animals were slaughtered to determine the villus height (VH), crypt depth (CD), VH : CD ratio and villi density (VD). The remaining 60 animals were allocated into a randomized block design with 4×3 factorial arrangement (four diets: C - control, G - glutamine, GA - glutamic acid and N - nucleotides; three slaughter ages: 7, 14 and 21 days post-weaning) with five piglets slaughtered per treatment. In carbon turnover trial, 123 animals were used. At day 0 (baseline), three animals were slaughtered to quantify the δ 13C half-life (T50%) and the 99% carbon substitution (T99%) on intestinal mucosa. The remaining 120 animals were blocked by three weight categories (light, medium and heavy) and, randomly assigned to pen with the same four diets from the previous trial with one piglet slaughtered per weight category per treatment at days 1, 2, 4, 5, 7, 9, 13, 20, 27 and 49 after weaning. Morphometric analyses have yielded no consistent results regarding the action of the evaluated additives, and few reproducible age-related effects. The N diets determined lower T50% values (5.18 days) and T99% (17.21 days) than G and C diets (T50%=7.29, 7.58 days and T99%=24.22, 25.17 days, respectively) in the duodenal mucosa. In jejunum, the N, GA and G diets determined the lowest T50% means (4.9, 6.2 and 6.7 days, respectively) and T99% means (15.34, 21.10 and 21.84 days, respectively) in comparison with C diets (T50%=7.44 and T99%=24.72 days). The inclusion of the additives in the diets of piglets accelerated the carbon turnover in piglets during the post-weaning period. The stable isotopes technique (δ 13C) is an important methodology in studies of additives with trophic effects on the intestinal mucosa of the piglets.

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Most of amino acid (AA) digestibility values for feed ingredients are obtained using pigs cannulated in the distal ileum. The ileal-cannulated pig model uses pigs older than six weeks due to difficulties related to implanting the T-cannula in distal ileum of younger pigs and complications during the post-surgical recovery. However, to properly formulate the diet of weaned pigs, the nutritive value of feed ingredients should be determined with younger pigs. Thus, 25 weaned pigs were used to determine the apparent total tract digestibility (ATTD) of nutrients, energy, and apparent ileal digestibility (AID) and standardized ileal digestibility (SID) ileal AA digestibility of broken rice (BR), with or without multicarbohydrase (MC) and phytase (Phy) supplementation. Piglets were weaned at 23 d of age and individually housed in digestibility cages until 45 d of age. The trial consisted of 7 d of adaptation to the experimental diets and 3 d of excreta (feces and urine) collection. Ileal digesta was collected at slaughter (about 6 weeks of age). A completely randomized experimental design was used to determine the effects of MC and Phy. Reference diets (RD, 5% casein) was replaced by 30% of BR with or without MC, Phy, or MC+Phy. The RD was used to quantify endogenous AA losses. BR with Phy supplied had increased the ATTD of dry matter (p<0.05) and SID of histidine (p = 0.05), arginine, leucine, lysine, valine, alanine, and proline (p<0.05). BR with MC had been increased digestible energy and protein and SID for histidine (p<0.05). There was no interaction between Phy and MC on the BR nutrient digestibilities. Standardized amino acid digestibilities of BR, without enzymes, were lower than those values reported in the literature. The MC and Phy improved the digestibility of some nutrients and energy of BR in post-weaned piglet diets.

RESUMO

Castration is a controversial practice in swine production because in some countries is still performed without anaesthesia, and therefore causes intense suffering and stress to animals. This study investigated the effect of pre-surgical administration of local anaesthesia (LA) on the growth performance of piglets until the end of the growth phase (102 days). Piglets aged 3 to 5 days were selected in pairs of similar weights and same age. They were originated from 22 litters. The groups were randomly assigned to one of two treatments. Castration was performed with (LA; n = 45) or without (NLA; n = 45) intra-testicular administration of 0.5 mL of 2% lidocaine plus adrenaline per testicle, administered by an automatic repeating vaccinator. Castration was performed 10 min later. Average daily weight gain and economic impact were evaluated between the intervals before castration until 21 (weaning phase), before castration until 60 (end of the initial nursery phase) and before castration until 102 (growth phase) days of age. Average daily weight gain data were analyzed by comparing the average daily weight gain between the weaning phase, 60 and 102 days of age versus the initial weight (pre-castration). At the end of the growing phase, animals treated with LA showed greater weight gain than animals castrated without anaesthesia. LA also showed improved cost:benefit ratio and theore might provide greater economic benefit under the conditions used in this study. Our findings have proved that castration with LA improves long-term weight gain of piglets.

RESUMO

O objetivo do trabalho foi avaliar o desempenho de leitões alimentados com duas fontes de óleos (soja e palma) em associação com maltodextrina e do blend de óleo de palma microencapsulado com maltodextrina, bem como os coeficientes de digestibilidade aparente dessas dietas. Utilizaram-se 162 leitões desmamados aos 21 dias, com peso médio inicial de 5,42 ± 0,55 kg, os quais foram distribuídos em delineamento de blocos ao acaso em três tratamentos e dezoito repetições compostas de três animais. Os tratamentos avaliados foram T1: rações com óleo de soja [3,03% nas dietas pré-iniciais (I) e iniciais (II)] e maltodextrina (10,00% na I e 5,93% na II); T2: rações com óleo de palma (3,03% na I e II) e maltodextrina (10,00% na I e 5,93% na II); T3: rações com óleo de palma microencapsulado pela maltodextrina na forma de blend (10,00% na I e II) e maltodextrina adicional ao blend (4,07% na I), para que a percentagem de maltodextrina permanecesse idêntica nas rações dos três tratamentos. Os dados de desempenho e digestibilidade foram submetidos à análise de variância, respectivamente, pelo procedimento MIXED e GLM do pacote estatístico SAS, sendo as médias comparadas pelo teste de Tukey (P0,05) para o CDR, GDP e CA dos leitões submetidos aos diferentes tratamentos. O CDA da MS foi 4,25% menor (P<0,05) para a dieta com óleo de palma microencapsulado pela maltodextrina em relação à dieta com óleo de soja...

The objective of this study was to evaluate the performance of piglets fed two sources of oil (soybean and palm oil) combined with maltodextrin and a blend of palm oil microencapsulated with maltodextrin, as well as the apparent digestibility coefficients of these diets. A total of 162 piglets weaned at 21 days, with a mean initial weight of 5.42 ± 0.55 kg, were allocated in a randomized block design consisting of three treatments and 18 replicates of three animals each. The following treatments were evaluated: T1: diet containing soybean oil [3.03% in the pre-initial (I) and initial (II) diets] and maltodextrin (10.0% in I and 5.93% in II); T2: diet containing palm oil (3.03% in I and II) and maltodextrin (10.0% in I and 5.93% in II); T3: diet containing a blend of palm oil microencapsulated with maltodextrin (10.0% in I and II) and maltodextrin added to the blend (4.07% in I) so that the percentage of maltodextrin would be identical in the diets of the three treatments. The performance and digestibility data were submitted to analysis of variance using the MIXED and GLM procedures, respectively, of the SAS package and means were compared by the Tukey test (P0.05) in DFI, ADG or FC were observed between piglets submitted to the different treatments. The ADC of dry matter was 4.25% lower (P<0.05) for the diet containing palm oil microencapsulated with maltodextrin compared to the soybean oil diet. The ADC of ether extract was 54% higher (P<0.05) in the soybean oil diet compared to the palm oil diet, which negatively affected the ether extract digestibility coefficient...

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RESUMO

O objetivo do trabalho foi avaliar o desempenho de leitões alimentados com duas fontes de óleos (soja e palma) em associação com maltodextrina e do blend de óleo de palma microencapsulado com maltodextrina, bem como os coeficientes de digestibilidade aparente dessas dietas. Utilizaram-se 162 leitões desmamados aos 21 dias, com peso médio inicial de 5,42 ± 0,55 kg, os quais foram distribuídos em delineamento de blocos ao acaso em três tratamentos e dezoito repetições compostas de três animais. Os tratamentos avaliados foram T1: rações com óleo de soja [3,03% nas dietas pré-iniciais (I) e iniciais (II)] e maltodextrina (10,00% na I e 5,93% na II); T2: rações com óleo de palma (3,03% na I e II) e maltodextrina (10,00% na I e 5,93% na II); T3: rações com óleo de palma microencapsulado pela maltodextrina na forma de blend (10,00% na I e II) e maltodextrina adicional ao blend (4,07% na I), para que a percentagem de maltodextrina permanecesse idêntica nas rações dos três tratamentos. Os dados de desempenho e digestibilidade foram submetidos à análise de variância, respectivamente, pelo procedimento MIXED e GLM do pacote estatístico SAS, sendo as médias comparadas pelo teste de Tukey (P<0,05). O consumo diário de ração (CDR), ganho diário de peso (GDP) e conversão alimentar (CA) foram avaliados nos períodos de 0 a 16 dias e 0 a 32 dias pós-desmame. Na segunda semana experimental, os coeficientes de digestibilidade aparente (CDA) da matéria seca (MS), proteína bruta e extrato etéreo (EE) foram mensurados pelo método da coleta parcial de fezes. Não foram encontradas diferenças (P>0,05) para o CDR, GDP e CA dos leitões submetidos aos diferentes tratamentos. O CDA da MS foi 4,25% menor (P<0,05) para a dieta com óleo de palma microencapsulado pela maltodextrina em relação à dieta com óleo de soja...(AU)

The objective of this study was to evaluate the performance of piglets fed two sources of oil (soybean and palm oil) combined with maltodextrin and a blend of palm oil microencapsulated with maltodextrin, as well as the apparent digestibility coefficients of these diets. A total of 162 piglets weaned at 21 days, with a mean initial weight of 5.42 ± 0.55 kg, were allocated in a randomized block design consisting of three treatments and 18 replicates of three animals each. The following treatments were evaluated: T1: diet containing soybean oil [3.03% in the pre-initial (I) and initial (II) diets] and maltodextrin (10.0% in I and 5.93% in II); T2: diet containing palm oil (3.03% in I and II) and maltodextrin (10.0% in I and 5.93% in II); T3: diet containing a blend of palm oil microencapsulated with maltodextrin (10.0% in I and II) and maltodextrin added to the blend (4.07% in I) so that the percentage of maltodextrin would be identical in the diets of the three treatments. The performance and digestibility data were submitted to analysis of variance using the MIXED and GLM procedures, respectively, of the SAS package and means were compared by the Tukey test (P<0.05). Daily feed intake (DFI), average daily gain (ADG) and feed conversion (FC) were evaluated from 0 to 16 days and from 0 to 32 days postweaning. In the second week of the experiment, the apparent digestibility coefficients (ADC) of dry matter, crude protein and ether extract were measured by partial feces collection. No differences (P>0.05) in DFI, ADG or FC were observed between piglets submitted to the different treatments. The ADC of dry matter was 4.25% lower (P<0.05) for the diet containing palm oil microencapsulated with maltodextrin compared to the soybean oil diet. The ADC of ether extract was 54% higher (P<0.05) in the soybean oil diet compared to the palm oil diet, which negatively affected the ether extract digestibility coefficient...(AU)

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The objective of this study was to evaluate the effects on gamma radiation levels on the physical and microbiological characteristics of chicken breast meat. A completely randomized experimental design in a 4x2x3 factorial arrangement was adopted. Treatments consisted of four radiation concentrations (0, 2, 4, or 8kGy), two package sealing methods (with or without vacuum), and three storage times (01, 07, or 14 days), with ten replicates each, totaling 240 chicken breast fillets. Packaging and radiation had no influence (p>0.05) on chicken breast meat pH, water retention capacity, or presence of Salmonella spp. Breast fillets not submitted to radiation and vacuum packed presented higher water retention capacity (p 0.05) than those radiated at 4kGy and vacuum packed. Drip loss in fillets radiated at 8kGy and not vacuum packed was higher (p 0.05) than in non-radiated and non-vacuum packed fillets; however, both were not different from the other treatments. Coliform presence increased with storage time in non-radiated samples; however, when these were vacuum-packed, their development was slower. The results of the present experiment suggest that the use of a low radiation dose (2kGy), combined with vacuum packing, may minimize the harmful effects of storage on chicken breast fillets.

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RESUMO

The objective of this study was to evaluate the effects on gamma radiation levels on the physical and microbiological characteristics of chicken breast meat. A completely randomized experimental design in a 4x2x3 factorial arrangement was adopted. Treatments consisted of four radiation concentrations (0, 2, 4, or 8kGy), two package sealing methods (with or without vacuum), and three storage times (01, 07, or 14 days), with ten replicates each, totaling 240 chicken breast fillets. Packaging and radiation had no influence (p>0.05) on chicken breast meat pH, water retention capacity, or presence of Salmonella spp. Breast fillets not submitted to radiation and vacuum packed presented higher water retention capacity (p 0.05) than those radiated at 4kGy and vacuum packed. Drip loss in fillets radiated at 8kGy and not vacuum packed was higher (p 0.05) than in non-radiated and non-vacuum packed fillets; however, both were not different from the other treatments. Coliform presence increased with storage time in non-radiated samples; however, when these were vacuum-packed, their development was slower. The results of the present experiment suggest that the use of a low radiation dose (2kGy), combined with vacuum packing, may minimize the harmful effects of storage on chicken breast fillets.(AU)

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Among the different feed additives studied in poultry production, clinoptilolite, an aluminosilicate capable of adsorbing harmful substances and of improving live performance and egg and meat quality, was evaluated. The objective of the present study was to evaluate the influence of dietary clinoptilolite and calcium levels on the performance and egg quality of layers. In total, 576 layers were distributed according to a completely randomized experimental design in a 3 x 4 factorial arrangement (three calcium levels - 2.5, 3.1, or 3.7% and four clinoptilolite levels - 0.0, 0.15, 0.25, or 0.50%), with 12 treatments of six replicates of eight birds each. The experiment included four 28-d cycles. The experimental diets were based on corn and soybean meal. Results were submitted to analysis of variance and means were compared by the test of Tukey at 5% significance level using SISVAR statistical package. There was a significant interaction between the evaluated factors for egg production and feed conversion ratio per dozen eggs and egg mass. The lowest calcium level resulted in worse performance and eggshell quality. Clinoptilolite levels affected albumen and yolk content. It was concluded that up to 0.50% inclusion of clinoptilolite in layer diets does not benefit layer performance or eggshell quality. Although the inclusion of only 2.5% calcium in layer diets is not recommended, it is possible to add 3.1% because it promoted similar results as the recommended level of 3.7%.(AU)

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RESUMO

Among the different feed additives studied in poultry production, clinoptilolite, an aluminosilicate capable of adsorbing harmful substances and of improving live performance and egg and meat quality, was evaluated. The objective of the present study was to evaluate the influence of dietary clinoptilolite and calcium levels on the performance and egg quality of layers. In total, 576 layers were distributed according to a completely randomized experimental design in a 3 x 4 factorial arrangement (three calcium levels - 2.5, 3.1, or 3.7% and four clinoptilolite levels - 0.0, 0.15, 0.25, or 0.50%), with 12 treatments of six replicates of eight birds each. The experiment included four 28-d cycles. The experimental diets were based on corn and soybean meal. Results were submitted to analysis of variance and means were compared by the test of Tukey at 5% significance level using SISVAR statistical package. There was a significant interaction between the evaluated factors for egg production and feed conversion ratio per dozen eggs and egg mass. The lowest calcium level resulted in worse performance and eggshell quality. Clinoptilolite levels affected albumen and yolk content. It was concluded that up to 0.50% inclusion of clinoptilolite in layer diets does not benefit layer performance or eggshell quality. Although the inclusion of only 2.5% calcium in layer diets is not recommended, it is possible to add 3.1% because it promoted similar results as the recommended level of 3.7%.

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The objective of the present study was to evaluate the effect of clinoptilolite and calcium levels on uric acid and calcium blood profile and bone quality of commercial layers. A total of 576 birds were distributed according to a completely randomized experimental design in a 3x4 factorial arrangement (calcium levels of 2.5, 3.1, or 3.7% and clinoptilolite levels of 0.0, 0.15, 0.25, or 0.50%), into 12 treatments with six replicates of eight birds per cage (experimental unit). The experimental period was 112 days. The experimental diets were based on corn and soybean meal. Results were submitted to analysis of variance and means were compared by the test of Tukey at 5% significance level using SISVAR statistical package. Blood uric acid was significantly influenced by the interaction of the evaluated factors. Clinoptilolite levels significantly increased blood calcium levels. There was no effect of dietary calcium levels on any of the evaluated characteristics. It was concluded that feeding layers with up to 0.50% clinoptilolite does not benefit blood uric acid and calcium concentrations and does not affect their bone quality. When layers at the end of the first laying cycle are fed ad libitum and present 119.50g/hen/day average feed intake, 3.1% dietary calcium promotes 3.7g/hen/day calcium intake, which is sufficient to maintain adequate calcium blood levels and bone quality.(AU)

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