Lúcio Vilela Carneiro Girão

Phage display (PD) is a tool for developing new molecules to control pathogens. Peptides selected by PD are commonly synthesised and tested, but the use of phage M13 displaying the selected peptides as a direct biding in the intestinal tract has not yet been tested. This study evaluated whether phage M13 can remain viable in the chicken gastrointestinal tract and whether it causes injury or humoral immune response. We inoculated phage M13 or E. coli ER2738 (ECR) infected with M13 into birds at different ages. We found the virus in faeces at 5 or 13 days after inoculation, just when it infected the ECR. The presence of phage M13 or ECR did not result in gut injuries and had no impacts on weight gain and bird health. Furthermore, the levels of IgY were similar in all treatments, which indicates that the virus can be used in chicken until 42 days without being recognised by the immune system. This work provides a scientific basis for the use of PD as a tool in numerous applications to control different pathogens.

This study aimed to evaluate crude corn oil with high acidity (CCOHA) as a surrogate for degummed soybean oil (DSO) in broiler diets. The design was completely randomized, with four treatments and ten replicates. Each box contained 40 birds (male), totaling 1600 Cobb Slow birds. Treatments consisted of two sorghum-based diets, one with DSO (SSO) another with CCOHA (SCO), and two corn-based diets, one with DSO (CSO) another with CCOHA (CCO). At 30 days of age, a digestibility test was performed using total excreta collection to determine apparent metabolizable energy (AME) and nitrogen-corrected AME (AMEn) from test rations. At 42 days of age, we evaluated live weight (LW), feed intake (FI), feed conversion (FC), carcass yield (CY), and the yields of breast with bone and skin (BWBS), skinless boneless breast (SBB), thigh (T), drumstick (D), and wing (W), as well as breast centesimal composition. Neither corn nor sorghum-based diets with CCOHA showed differences between AME and AMEn. Both DSO and CCOHA diets showed no differences in LW, FI, FC, carcass and cuts yields when using CCOHA. Regarding breast composition, no differences in dry matter and in the levels of crude protein, fat, and mineral matter were observed. We may conclude that CCOHA had no effect on the performance variables, carcass and cuts yields, and broiler meat quality.

1. The aim was to determine the importance of a contaminated diet as a possible cause of Campylobacter jejuni infection in broilers. 2. This study evaluated the viability of C. jejuni in both starter and finisher diets and the interference from other mesophilic bacteria in this viability. 3. Starter and finisher samples of broiler diet were deliberately contaminated with 3 or 5 log CFU·g⁻¹ of C. jejuni (NCTC 11351) and then maintained at two different storage temperatures (25°C or 37°C) for 3 or 5 d. 4. C. jejuni survived during this period and, when inoculated at 10³ CFU·g⁻¹, multiplied with greater proliferation at a storage temperature of 37°C. There was no relationship between the amount of mesophilic bacteria and C. jejuni viability. 5. This study highlights the importance of the diet in the epidemiology of C. jejuni in broilers.

Alguns autores consideram os minerais de fontes orgânicas mais biodisponíveis para a nutrição de suínos quando comparados à minerais de fontes inorgânicas. Para avaliar a biodisponibilidade relativa do ferro proveniente da fonte orgânica carbo-amino-fosfo-quelato de ferro (CAFQF), foi conduzido um experimento com 126 leitões de linhagem comercial, utilizando o sulfato de ferro (S) como padrão. O delineamento experimental foi inteiramente casualizado com sete tratamentos (dieta sem adição de fonte específica de ferro, dietas com 50, 100 e 150 ppm de ferro na forma de S e dietas com 50, 100 e 150 ppm de ferro na forma de CAFQF), seis repetições e três animais por unidade experimental. Parâmetros de desempenho (ganho de peso médio diário – GMD, conversão alimentar – CA) e variáveis sanguíneas (hemoglobina – Hb, hematrócrito – Ht, transferrina – TR, capacidade latente de ligação do ferro – CLLF, capacidade total de ligação do ferro – CTLF, ferro sérico – FS e índice de saturação da transferrina – IST) foram avaliados. Ao final do experimento um leitão por unidade experimental foi abatido para a retirada do fígado e braço para avaliação da concentração de ferro por espectrometria de absorção atômica em chama (FAAS). As fontes de ferro avaliadas apresentaram resultados semelhantes para as variáveis de interesse, mas o aumento da ingestão de ferro resultou em aumento linear nos valores de GMD, Hb, Ht, FS e IST e redução linear nos valores de CA, TR, CLLF e CTLF. Para leitões desmamados a biodisponibilidade do ferro proveniente do CAFQF é similar à do S.Some authors consider minerals from organic sources more bioavailable for pig nutrition in comparison with inorganic sources. To evaluate the relative iron bioavailability from the organic source iron carbo-amino-phospho-chelate (ICAPC) to weanling piglets, it was conducted an experiment with 126 commercial piglets, using iron sulfate monohydrate (S) as standard. The experiment had a randomized block design with seven treatments (diet without adding specific source of iron, diet with 50, 100 and 150 ppm iron from S and diet with 50, 100 and 150 ppm iron from ICAPC), six replications and three animals per experimental unit. Performance parameters (average daily gain - ADG, feed:gain ratio - F:G) and blood variables (hemoglobin - Hb, hematocrit - Ht, transferrin -TR, latent iron-binding capacity - LIBC, total iron-binding capacity - TIBC, serum iron - Fe and transferrin saturation index - TSI) were evaluated. At the end of the experiment a piglet from each experimental unit was slaughtered and its liver and spleen removed for assessment of iron concentration by flame atomic absorption spectrometry (FAAS). The evaluated sources of iron yielded similar results for the variables of interest, but the increase in iron intake was followed by a linear increase in ADG, Hb, Ht, Fe and TSI as well as a linear decrease in the values of F:G, TR, LIBC and TIBC. Iron bioavailabilities from both ICAPC and S sources are similar for weanling piglets

One hundred and twenty six piglets from a commercial genetic strain weaned at 21 days of age (6.11 +/- 0.42 kg) were used to evaluate the effects of supplementation levels of organic sources of trace minerals in the diets of weaned piglets on performance, occurrence of diarrhea, excretion of copper and zinc in the feces, and hematological parameters. A completely randomized block design was adopted, composed of six treatments (diets containing 100% of inorganic trace minerals premix at 3.00 kg/T; diets containing 0, 25, 50, 75 or 100% of organic trace minerals premix, equivalent to 0; 0.75; 1.50; 2.25 or 3.00 kg/T, respectively), seven replicates and three animals per plot. During the experimental period (from 21 to 63 days of age), the increasing levels of organic trace minerals premix in the diets determined a quadratic effect on daily weight gain (DWG), feed conversion (FC), percentage of hematocrit (Ht), hemoglobin (Hb), mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), platelets (Pt), and a linear increase of Cu and Zn concentrations in feces. The comparison of means between the treatment with inorganic trace minerals premix and the other treatments showed that piglets fed diets without trace minerals premix had lower values of DWG, Ht, Hb, MCH, MCV, Pt and the worst FC value of piglets fed diets containing 25% of organic trace minerals premix presented lower values of Ht and Hb, in comparison with those fed diets with 100% of inorganic trace minerals premix. Inorganic trace minerals premix can be substituted by organic trace minerals premix at a lower level of inclusion in diets for weaned piglets

An experiment was carried out to evaluate the performance, carcass composition, cutting yields and economic viability of 5 or 10 ppm of ractopamine hydrochloride (RAC) in diets for barrows and gilts from 94 to 130 kg. Sixty commercial hybrid pigs within a gender, were individually kept in pens and assigned a randomized experimental block design, in a 3 × 2 factorial arrangement, with three levels of RAC (0; 5 and 10 ppm) and two sexs (barrows and gilts). There were no RAC × sex interactions for all evaluated parameters. There were significant improvements for the groups of RAC-treated on final weight, average daily gain (ADG) and feed:gain (F:G). The RAC, independent from the level (5 or 10 ppm), improved the F:G, but did not influence the average feed intake. The gilts had smaller final weight, smaller average feed intake and better F:G. The supplementation with 10 ppm of RAC provided better carcass yield, better longissimus muscle area and better meat percentage. The pigs supplemented with RAC showed better tenderloin yield, better ham weight and better meat percentage of ham. The gilts had better meat percentage, better back fat thickness, bigger belly flexibility and smaller fat thickness of the belly than barrows. On economic viability, the RAC-treated pigs increased the allowance index, gross earnings and net earnings. Compared to the barrows, gilts showed lower total cost, better allowance index and higher net earnings. The supplementation with 5 ppm of RAC was enough to improve performance, carcass composition and cutting yields in the heavy pigs. Furthermore, 5 or 10 ppm of RAC was economically viable and the heavy gilts were more profitable than heavy barrows.

O objetivo deste trabalho foi avaliar diferentes níveis de lisina digestível (LISD), em rações com reduzido teor de proteína bruta (PB), por meio do desempenho e das características de carcaça de suínos dos 20 aos 50kg. Foram utilizados 40 suínos machos, castrados, de elevado potencial para ganho de carne (peso inicial de 22,5±1,4kg e final de 47,8±3,4kg), distribuídos em delineamento em blocos casualizados, com cinco tratamentos (quatro níveis de LISD - 0,7; 0,9; 1,1 e 1,3% - em rações com 14% PB e um tratamento-controle, formulado de acordo com as tabelas brasileiras, com 1,03% LISD e 18% de PB) e quatro repetições, durante 31 dias. Não houve diferença (P>0,05) entre os níveis de LISD, em rações com 14% PB para o ganho de peso diário; entretanto, apenas o nível 0,7% de lisina foi diferente em relação ao tratamento-controle. Não houve diferença (P>0,05) com relação ao consumo, mas houve um efeito linear crescente (P0,05) para espessura de toucinho. Conclui-se que o nível de 1,1% de LISD em rações com reduzido teor de PB melhora a qualidade da carcaça, sem afetar o desempenho.