A Comparative Study of the Effect of Non-Antibiotic Feed Additives on Experimental Colonization of Salmonella Enterica Serovar Enteridis and Intestinal Pathomorphology in Broiler Chickens

The objective of this study was to evaluate the effect of eubiotics on the intestinal morphology of broilers. For this purpose, 125 birds were divided into six groups with two replicates each (10 birds in each replicate). Group A was given a Basal diet. All groups except group A were challenged with Salmonella enterica serovar Enteritidis. Group B was provided the basal diet, group C was fed a Probiotic-added diet; group D was fed a Prebiotics-based diet; group E was given essential oils plus the basal diet; and group F was provided with organic acids plus the basal diet. Two separate experiments were carried out for Salmonella recovery, checking the cecal tonsils and conducting an intestinal pathomorphic evaluation. Villus length, villus width, villus surface area, and crypt depth were measured by micrometry. There was an overall improvement (p<0.05) in intestinal morphometric parameters for all the treatment groups except for the negative control group, which showed the lowest villus height and villus depth values. Maximum villus height (p<0.05) of the duodenum was achieved by group E, which was fed a diet containing essential oils, whereas a maximum villus surface area index (p<0.05) was recorded for the birds of Group D, which were fed a diet containing prebiotics. Maximum villus height (p<0.05) and surface area index in ileum mucosa was recorded (p<0.05) in the birds of group D (treated with prebiotics). It is concluded that there is an overall increase in the gut histology of broilers fed non-antibiotic based feed.(AU)

Performance, Gut Integrity, Enterobacteria Content in Ceca of Broiler Fed Different Eubiotic Additives

An experiment was carried out to study the effect of different eubiotics on productive characteristics, intestinal integrity, as well as the content of enterobacteria in the cecum of broiler chickens. A completely randomized design with five treatments and 8 replicates of 25 birds each was used. In total 1000 mixed broiler chickens from Ross308 strain, one day old were obtained from a commercial hatchery. The birds were housed on concrete floors in a conventional house. A sorghum+soybean meal control diet was used, to which the additives under study were added. The treatments were distributed as follows: T1 = Control diet without antibiotic or eubiotic; T2 = T1 + bacteriophages; T3 = T1 + antibiotic; T4 = T1 + probiotic; T5 = T1 + symbiotic. The results obtained at 49 days of age for weight gain and feed conversion rate improved (p<0.05) with the addition of the antibiotic and eubiotics. A lower (p<0.05) intestinal density was observed with the probiotic. The height, width, and area of villi in duodenum was higher (p<0.05) when antibiotic and eubiotics were included. In the histological score, in duodenum, the antibiotic and eubiotics resulted with a higher score (p<0.05), associated to a physiological and controlled inflammation response that allowed improving productivity. Finally, the relative expression of enterobacteria, such as Lactobacillus salivarius, allowed associating positive changes in the microbiome and better productive parameters when including the symbiotic, with comparable results to the antibiotic when including the eubiotics.(AU)

Natural Growth Promoters Replacing Traditional Growth Promoters in Diets for Light Replacement Pullets: A Systematic Approach

The effect of using natural growth promoters (NGP) to replace traditional antimicrobials on performance, biometry of digestive and reproductive organs, sexual maturity and bone characteristics of replacement pullets was evaluated; and the relationship between these variables according to the diets was verified. Eight-week-old birds were randomly assigned to a completely randomized design and fed different diets: negative control (without growth promoters); positive control - conventional growth promoter; organic acids (OA); symbiotic (S); essential oil (EO); OA + S; and EO + S. The performance, relative weight of digestive and reproductive organs and length intestines, height and crest length, sternum length, bone quality and sexual maturity of birds were similar (p>0.05) between treatments. The heat map combined with cluster analysis showed a uniform static pattern with the formation of three horizontal groups formed by the treatments: 1) negative control, S and OA + S; 2) positive control and OE and 3) OA and OE + S. A null relationship between the treatments and the variables under study was observed. The principal components analysis revealed an association of variables in three components with 60.55% of variation. NGP can replace traditional promoters, as they do not interfere with performance, biometrics or sexual maturity. Height and length are predictive variables for the development of reproductive organs, especially the oviduct. A similarity was identified through multivariate techniques between symbiotic and organic + symbiotic acids; positive control and essential oils; and organic and symbiotic acids + essential oils.(AU)

Effect of a Feed Additive Based on Organic Acids and Tangerine Wort (Citrus reticulata) as Growth Promoter for Broiler Chickens

Feed additive alternatives to antibiotics, such as organic acids, and substances rich in polyphenols, such as tangerine wort, can promote improved intestinal health in broilers by modulating the microbial population and improving nutrient utilization. In this work, a product which combines organic acids (fumaric acid 0.5%, lactic acid 5.13%, citric acid 5.44% and ascorbic acid 1.2%) and tangerine wort (Citrus reticulata) 8.36% was studied. To determine the effect and the most appropriate level of inclusion of product in the diet of broilers, an experiment was carried out with 1400-day-old male chicks, in a conventional poultry house, evaluating the performance until 42 days of age. The birds were housed in RCB design with 5 treatments and 7 replicates of 40 birds each, and the diets with the additive inclusions were evaluated: A250 (250 mg/kg), A500 (500 mg/kg), A1000 (1000 mg/kg), a negative control (NC, not supplemented), and a positive control (PC, 10 mg/kg of enramycin). The diets were formulated based on corn and soybean meal, containing added phytase and without anticoccidial; the additives replaced an inert in the basal diet. Performance characteristics, microbiota count, morphometry and jejunum morphology were evaluated. Considering the overall experimental period, the inclusion of the alternative additive based on organic acids and tangerine wort at different levels (250, 500 and 1000 mg/kg) did not result in difference from the negative control diet or the positive control with the inclusion of the antibiotic enramycin for performance traits (p>0.05), as well as for the microbiota count, morphology, jejunal morphometry and viability. Considering the period of 29-35 days alone, treatment with 500 mg/kg of alternative additive improved weight gain and feed intake of the chickens (p<0.05), but had no effect on feed conversion.(AU)

A blend of thyme and rosemary powders with poultry by-product meal can be used as a natural antioxidant in broilers

A total of 500, 14-d old male Ross 308 broilers were allocated into five treatments (4 replicates each) including: a negative (NC) and positive control diet (PC) which supplemented without and with 7% poultry by-product meal (PBPM), respectively and three levels of additive supplementation of thyme and rosemary powders in the basal diets: 0.750% rosemary powder (PCR); 0.375% thyme powder + 0.375% rosemary powder (PCRT), and 0.750% thyme powder (PCT) rosemary powder. The PCRT diet improved (p<0.05) average daily gain and feed conversion ratio by 5.62 and 10.37% compared to PC, respectively. The serum concentration of lipids (triglycerides, cholesterol, high-density lipoprotein, and low-density lipoprotein) was decreased while the ilealvillus heightand ratio of villus height to crypt depth as well as ileal microbiota population were improved(p<0.05) in response to inclusion PCRT diet compared to PC diet. The blood serum concentration of malondialdehyde was statistically decreased (p<0.05) by supplementation of PCRT in broiler diets. Our results suggested that supplementation of a blend of thyme and rosemary powders at the level of 0.375% of each into broiler diet during d 14-42 has merit to be used as a natural antioxidant in diets formulated by PBPM.(AU)

Semen quality and sperm characteristics in broiler breeder cockerels fed vitamin E during hot season

Thirty-two Arbor Acres (AA) cockerels aged 27 weeks were used to determine the effect of vitamin E (VE) on the semen characteristics and sperm quality during hot season. The birds were fed diets containing 0, 50, 100 and 150mg VE kg-1 feed. There were 4 replicates and two birds per replicate. Semen collection was done thrice a week for three weeks in all birds. Dietary vitamin E significantly (p < 0.05) increased the semen volume (SV) and number of sperm cells (NS) in AA cockerels. CONTROL birds (0.71 mL) had lower SV than birds fed 150 mg VE (0.94 mL). Birds on 100 and 150 mg VE recorded similar NS, which was higher than 0 and 50 mg VE groups. The least NS was in the CONTROL group. Sperm abnormality gradually (p < 0.05) decreased as dietary VE increased from 0 to 150 mg. Significant (p < 0.01) effect of dietary VE was recorded in percentage live sperm (PLS). Semen from cockerels on VE treatment had higher PLS than the CONTROL. In conclusion, it may be beneficial to supplement the broiler breeder cockerel diet with VE up to 150 mg kg-1 feed during hot season as it increased SV, NS and PLS and decreased sperm abnormality.(AU)

Propolis extract as a feed additive of the Nile tilapia juveniles / Extrato de própolis como aditivo alimentar para juvenis de tilápia-do-nilo

This study was conducted to investigate the effects of dietary propolis alcohol extract supplementation on growth performance, digestibility, intestinal morphometry, and physiologic parameters Nile tilápia (Oreochromis niloticus L.) juveniles. For performance experiment and intestinal morphometry, 120 fish averaging 1.41±0.3g were randomly distributed into 24 tanks (70L each) in a closed recirculation water system with constant aeration and biofilter. The animals were distributed into four treatments using a completely randomized design with six replicates per treatment. The treatments consisted of four pellet feeds with different alcohol propolis concentrations extract (AEP) (0.0, 0.5, 1.0 and 1.5gkg-1). The performance experiment period was conducted for 45 days. For the digestibility experiment, an inert marker in the feed and the adapted Guelph feces collecting system were used. The results showed no differences in the performance parameters, crude protein apparent digestibility and dry matter of the feeds, intestinal morphometry, and physiologic parameters. However, there was an increasing linear effect on the energy digestibility with increasing PAE concentrations in the fish feed. The usage of the propolis extract supplementation levels of 1% is recommended for optimum effect on villus morphometry in Nile tilapia.

Avaliaram-se os efeitos da suplementação de extrato de própolis na dieta sobre o desempenho, a digestibilidade, a morfometria intestinal e os parâmetros fisiológicos de juvenis de tilápia-do-nilo (Oreochromis niloticus). No desempenho e na morfometria intestinal, 120 peixes (1,41±0,3g) foram distribuídos aleatoriamente em 24 tanques (70L cada), em sistema de recirculação de água com aeração constante e biofiltro. Os animais foram distribuídos em quatro tratamentos, num delineamento inteiramente ao acaso, com seis repetições por tratamento. Os tratamentos consistiram em quatro rações, com concentrações de extrato de própolis (AEP) (0,0, 0,5, 1,0 e 1,5g kg-1). O período experimental foi de 45 dias. Para a digestibilidade, foi utilizado um sistema adaptado de Guelph para a coleta de excretas e um marcador inerte na ração. Os resultados não mostraram diferenças nos parâmetros de desempenho, digestibilidade aparente da proteína bruta e da matéria seca dos alimentos e morfometria intestinal, bem como nos parâmetros fisiológicos. No entanto, houve um efeito linear crescente sobre a digestibilidade da energia com o aumento das concentrações de AEP na ração. Os resultados também indicaram que a suplementação com 1% de própolis teve efeito positivo na morfometria intestinal de tilápia-do-nilo, sendo esse o nível recomendado na dieta.

Different phytase levels and energy densities in broiler diets on performance, nutrient digestibility, and bone integrity from 28 to 35 days of age / Diferentes níveis de fitase e de densidades energéticas em dietas de frangos de corte sobre desempenho, digestibilidade de nutrientes e integridade óssea de 28 a 35 dias de idade

The study was carried out with the objective of evaluating the effects of using phytase levels at different energy densities in the diet of broilers, from 28 to 35 days of age. The experimental diets contained increasing levels of apparent metabolizable energy corrected for nitrogen balance and different levels of phytase. Growth performance variables, nutrient digestibility, as well as variables related to bone integrity were examined. Diets containing 500 FTU/kg in combination with 3150kcal.kg-1 of AMEn resulted in better growth performance. Supplementation with 500 and 1000 FTU/kg in the diets provide better coefficients of apparent and ileal digestibility of calcium and phosphorus, but negatively influence the deposition of calcium, phosphorus, dry matter, and ash in the tibia, in addition to adversely affecting the breakage and area of these bones in broilers. Bone length and the levels of magnesium and zinc present in the tibias were not influenced by the energy and phytase levels of the diets. There is no interaction between the different energetic densities and the phytase doses in the variables analyzed in the studied period. Increasing the energy density of diets resulted in improved apparent and ileal digestibility for most nutrients.

O estudo foi realizado com o objetivo de avaliar os efeitos da utilização de níveis de fitase em diferentes densidades energéticas na dieta de frangos de corte, no período de 28 a 35 dias de idade. As dietas experimentais contiveram níveis crescentes de energia metabolizável aparente corrigida para balanço de nitrogênio e diferentes níveis de fitase. Foram avaliadas variáveis de desempenho zootécnico, digestibilidade de nutrientes e variáveis relacionadas à integridade óssea. Dietas contendo 500 FTU/kg de fitase em combinação com 3150kcal.kg-1 de EMAn resultam em melhor desempenho zootécnico. A suplementação com 500 e 1000 FTU/kg nas dietas propicia melhores coeficientes de digestibilidade aparente e ileal do cálcio e do fósforo, mas influencia negativamente na deposição de cálcio, fósforo, matéria seca e cinzas das tíbias, além de afetar adversamente a quebra e a área desses ossos em frangos de corte. O comprimento do osso e os níveis de magnésio e zinco presentes nas tíbias não são influenciados pelos níveis energéticos e de fitase das dietas. Não há interação entre as diferentes densidades energéticas e as doses de fitase nas variáveis analisadas no período estudado. O aumento da densidade energética das dietas resulta em melhora na digestibilidade aparente e ileal para a maioria dos nutrientes.

Complexo enzimático em rações para leitões nas fases pré-inicial e inicial / Enzymatic complex in piglet feeds in the pre-initial and initial phases

Objetivou-se, com este trabalho, avaliar o efeito da utilização de complexo enzimático em rações para leitões sobre o desempenho zootécnico nas fases pré-inicial e inicial. Foram utilizados, para isso, 292 leitões, machos castrados e fêmeas, de linhagem comercial. O período de suplementação da enzima, na maternidade, foi do sétimo ao vigésimo primeiro dia de idade, e, na creche, foi do desmame até a saída para a fase de crescimento. O delineamento utilizado foi inteiramente casualizado, sendo a matriz e sua leitegada consideradas a unidade experimental durante a maternidade e uma baia com dez leitões na creche. Na maternidade, os tratamentos consistiram em: T1 - ração controle, sem complexo enzimático; T2 - ração controle com adição on top do complexo enzimático com inclusão de 5%. Na creche, foram definidos três tratamentos: T1 - ração controle; T2 - ração controle com inclusão on top de 5% do complexo enzimático na fase de maternidade; T3 - ração controle com inclusão de 5% de complexo enzimático nas fases de maternidade e creche. A suplementação durante a lactação não influenciou o desempenho da leitegada na maternidade até o 21º dia. Na creche, leitões alimentados com ração controle apresentaram maior peso inicial em relação aos suplementados na fase de maternidade e creche. Ao término da fase, os leitões mostraram desempenho semelhante, independente da dieta. Conclui-se que a inclusão do complexo enzimático na forma on top em dietas para leitões não influenciou parâmetros de desempenho na maternidade, porém, favoreceu a recuperação de leitões desmamados com menor peso.

This study aimed to evaluate the effect of using an enzymatic complex in piglet feeds on the zootechnical performance in the pre-starter and initial phases. For this purpose, 292 piglets, castrated males and females, of commercial lineage were used. The enzyme supplementation period in the maternity hospital was from the seventh to the twenty-first day of age, and in the nursery, it was from the waning until the exit for the growth phase. The design used was completely randomized, with the mother and her litter considered the experimental unit during maternity and a stall with 10 piglets in the nursery. In maternity, the treatments consisted of: T1 - control feed, without the enzymatic complex; T2 - control diet with on top addition of the enzymatic complex with 5% inclusion. Three treatments were defined at the nursery: T1 - control feed; T2 - control diet with inclusion on top of 5% of the enzymatic complex in the maternity phase; T3 - control feed with the inclusion of 5% enzymatic complex in the maternity and nursery phases. Supplementation during lactation did not influence litter performance in the maternity unit until 21 days. In the nursery, piglets fed with control feed had higher initial weight compared to those supplemented in the maternity and nursery phases. At the end of the phase, the piglets showed similar performance, regardless of diet. It is concluded that the inclusion of the enzymatic complex used in the on top form in diets for piglets did not influence performance parameters in maternity; however, it favored the recovery of weaned piglets with lower weight.

Effects of functional oil blend on performance, blood metabolites, organ biometry and intestinal morphometry in nursery piglets / Efeitos da mistura de óleo funcional no desempenho, metabólitos sanguíneos, biometria de órgãos e morfometria intestinal em leitões de creche

This study was conducted to assess the effects of functional oil (FO) blend on performance, blood metabolites, organ biometry and intestinal morphometry in piglets. A total of 128 crossbreed piglets (Landrace × Large White, 64 uncastrated males and 64 females, 21 d of age, and 6.79 ± 1.76 kg BW) were allocated in a randomized complete block design with two dietary treatments: a FO-free (FOF) diet or a diet based on added FO (1,500 mg/kg of diet with castor oil plus cashew nutshell oil). Piglets fed FO showed higher (p ≤ 0.05) average daily feed intake, daily body weight gain and final body weight after 23 d of study. For the total period, piglets fed FO showed greater (p = 0.007) feed conversion ratio. On d 23, higher serum total protein (p = 0.026) and globulin (p = 0.050) concentration, lower liver (p = 0.042) and stomach (p = 0.074) weight, and greater (p = 0.082) villi height (VH) in duodenum were observed in piglets fed FO. Nonetheless, piglets fed FOF showed greater (p = 0.054) ileal VH, but greater (p = 0.004) crypt depth (CD) in jejunum. Piglets fed FO showed higher VH to CD ratio in jejunum (p = 0.068) and duodenum (p = 0.074) on d 23 and 37, respectively. Based on the results, FO blend improved the performance of weaned piglets; however, it negatively affected the feed conversion ratio in the total period. Moreover, FO blend promoted changes in total protein concentrations and improvements in digestive and absorptive capacity assessed through VH to CD ratio, with a significant reduction in organs.

Este estudo foi conduzido para avaliar os efeitos de uma mistura de óleo funcional (OF) no desempenho zootécnico, nos metabólitos sanguíneos, na biometria de órgãos e na morfometria intestinal de leitões. Um total de 128 leitões mestiços (Landrace × Large White, 64 machos inteiros e 64 fêmeas; 21 dias de idade e peso corporal de 6,79 ± 1,76 kg) foram alocados em um delineamento de blocos casualizados completos, com dois tratamentos dietéticos: uma dieta sem OF (SOF) ou uma dieta baseada na adição de OF (1.500 mg/kg de dieta com OF de mamona e castanha de caju). Os leitões alimentados com OF apresentaram maior (p ≤ 0,05) consumo de ração diário médio, ganho de peso corporal diário e peso corporal aos 23 dias de experimento. Entretanto, os leitões que consumiram dietas com OF tiveram conversão alimentar superior (p = 0,007) no período total. No dia 23, houve aumento na concentração de proteína total (p = 0,026) e globulina (p = 0,050), menor peso de fígado (p = 0,042) e estômago (p = 0,074), e maior (p = 0,082) altura de vilosidade (AV) no duodeno em leitões que consumiram OF; entretanto, os leitões SOF tiveram (p = 0,054) AV superior no íleo, mas apresentaram (p = 0,004) profundidade de cripta (PC) superior no jejuno. Uma maior relação AV:PC no jejuno (p = 0,068) e duodeno (p = 0,074) foi observada em leitões com OF nos dias 23 e 37, respectivamente. Com base nos resultados, a mistura de OF melhorou o desempenho dos leitões desmamados; no entanto, afetou negativamente a taxa de conversão alimentar no período total. Além disso, a mistura de OF promoveu alterações nas concentrações proteínas totais e melhorias na capacidade digestiva e absortiva avaliadas através da relação AV:PC, com uma redução significativa nos órgãos.

Association of additives in supplemented grazing cattle during the finishing phase at the rainy season

The objectives were to evaluate the effects of monensin and virginiamycin, alone or combined, on supplemented Nellore cattle grazing tropical grass during the rainy season. Two experiments were conducted simultaneously to evaluate intake, digestibility, CH4 emissions, blood parameters, performance, and carcass characteristics (Exp. 1), and ruminal fermentation and relative abundance of ruminal microorganisms (Exp. 2). Animals (n = 92 Exp. 1 and n = 12 Exp. 2) were distributed in a completely randomized design and allocated in twelve paddocks composed of Urochloa brizantha (A. Rich.) Stapf. cv. Xaraés. A protein-energetic supplementation of 3 g/kg of BW per day was provided to all animals. Supplements were: without additives (WA), monensin alone at 80 mg/kg of product (MN), virginiamycin alone at 150 mg/kg of product (VM), and monensin (80 mg/kg of product) combined with virginiamycin (150 mg/kg of product; MNVM). Treatments did not affect intakes of total dry matter (DM), supplement DM, and nutrients. However, the intakes of forage DM and crude protein decreased in cattle fed MNVM compared with animals fed WA, MN, and VM. Total volatile fatty acids increased in animals fed VM. Ruminal NH3-N decreased, and pH increased in animals fed MN, VM, and MNVM. Relative abundance of total F. succinogenes and S. ruminantium decreased and R. flavefaciens increased in animals fed MN and VM at d 118. Treatments had no effect on enteric CH4 emissions. The average daily gain (ADG) and total gain were greater in cattle fed MNVM than in cattle fed MN. Combination of monensin and virginiamycin altered the rumen microbial populations but did not decrease enteric CH4 emissions. However, it decreased forage dry matter intake without altering the ADG and total weight gain, leading to an increase in feed efficiency. Results from this study indicate an advantage in including feed additives combined in the diet of supplemented Nellore cattle grazing tropical grass during the rainy season.

Combination of carbohydrases and essential oils improve dietary performance of feedlot steers on a high-energy diet / Associação de carboidrases e óleos essenciais melhoram o aproveitamento da dieta em novilhos confinados alimentados com dieta de alta densidade energética

Essential oils and enzymes are alternatives to feed additives for ruminants that aim to replace the use of ionophores and improve animal performance, but their mechanisms of action are different. Therefore, the present study aimed to verify if there is a synergistic effect in the combined use of enzymes carbohydrates and essential oils on the performance, ingestive behavior and carcass traits of steers fed a high-energy diet. During the finishing period of 78 days, 40 steers were assigned to four treatments: CON- control; ENZ- enzymatic complex; EO- essential oil blend; ENZ+EO - enzymatic complex combined with essential oil blend. Regardless of the feedlot periods, the ENZ+EO treatment caused a reduction in the dry matter intake (12.48%) compared to the control. The ENZ+EO treatment resulted in the lowest mean fecal output and, consequently, the highest dry matter digestibility (DMD) and starch digestibility (SD), compared to the other treatments. Animals that received EO and ENZ+EO in the diet spent more time in feeding. As for the number of times animals visited the feeding trough, the highest values were presented by the animals in the EO, ENZ and ENZ+EO treatments. For the carcass parameters, only the subcutaneous fat thickness on the rib was significantly different between treatments, with the highest values obtained by adding EO and ENZ+EO (8.80 and 8.10 mm respectively). Thus, the combination of carbohydrate enzymes and essential oils proved to be synergistically beneficial in relation to better use of nutrients and productive performance of feedlot steers.(AU)

Os óleos essenciais e as enzimas são alternativas de aditivos alimentares para ruminantes que visam substituir o uso de ionóforos e melhorar o desempenho animal, porém seus mecanismos de ação são distintos, diante disso, o presente estudo teve por objetivo verificar se há efeito sinérgico no uso associado de enzimas carboidrases e óleos essenciais sobre o desempenho, comportamento ingestivo e características de carcaça de novilhos recebendo dieta de alta densidade energética. Durante 78 dias, período de terminação, 40 novilhos foram distribuídos em quatro tratamentos: CON - controle; ENZ - complexo enzimático; OE - mistura de óleos essenciais; ENZ+OE - complexo enzimático associado a mistura de óleos essenciais. Independentemente dos períodos de confinamento, o tratamento ENZ+OE apresentou maior redução na ingestão de matéria seca (12,48%) quando comparado ao controle. O tratamento ENZ+OE foi o que apresentou a menor produção média de fezes e a maior digestibilidade da matéria seca (DMS) e digestibilidade do amido (DA), comparado aos demais tratamentos. Os animais que receberam dieta contendo OE e ENZ+OE passaram maior tempo se alimentando, já em relação ao número de vezes que os animais visitaram o cocho de alimentação, as maiores médias ficaram com os animais dos tratamentos OE, ENZ e ENZ+OE. Para os parâmetros avaliados em carcaça apenas a espessura de gordura subcutânea nas costelas apresentou diferença significativa entre os tratamentos, sendo as maiores médias obtidas pela adição de OE e ENZ+OE (8.80 e 8.10 mm, respectivamente). Dessa forma, a associação de enzimas carboidrases e óleos essenciais mostrou-se sinergicamente benéfica em relação ao melhor aproveitamento dos nutrientes e desempenho produtivo de novilhos confinados.(AU)

Effect of the addition of poultry by-product meal on the zootechnical performance of Nile tilapia fingerlings / Efeito da adição de farinha de vísceras de aves sobre o desempenho zootécnico de alevinos de tilápia do Nilo

This study has aimed to assess the inclusion of poultry by-product meal in the diets of Nile tilapia fingerlings on heterogeneous growth and zootechnical performance. We used 144 animals with a mean initial weight of 1.3 ± 0.02 g distributed in 24 polyethylene aquariums with a capacity of 80 L of water, connected to a recirculation system following a completely randomized experimental design with four treatments (0.0, 6.0, 12.0, and 18.0% of poultry by-product meal) and six replications. At the end of the experimental period, the following variables were evaluated: final weight, survival rate, weight gain, heterogeneous growth, average feed intake, feed conversion ratio, protein efficiency ratio, and hepatosomatic and liposomatic index. The treatments have had no effect on the variables analyzed in the performance test. Therefore, up to 18% poultry by-product meal can be included in Nile tilapia fingerling diets.(AU)

O presente estudo teve como objetivo avaliar o efeito da inclusão da farinha de vísceras de aves em dietas para alevinos de tilápia do Nilo, sobre o crescimento heterogêneo (CHet) e desempenho zootécnico. Foram utilizados 144 animais com peso médio inicial 1,3 ± 0,02 g, distribuídos em 24 aquários de polietileno com capacidade para 80 L de água, interligados a um sistema de recirculação seguindo um delineamento experimental inteiramente casualizado, com quatro tratamentos (0,0; 6,0; 12,0 e 18,0% de farinha de vísceras de aves) e seis repetições. Ao término do período experimental foram avaliados: peso final, taxa de sobrevivência, ganho em peso, crescimento heterogêneo, consumo de ração, conversão alimentar aparente, taxa de eficiência proteica, índices hepatossomático e lipossomático. Não foram observados efeitos dos tratamentos sobre as variáveis analisadas no ensaio de desempenho. Sendo assim, a farinha de vísceras de aves pode ser incluída até 18% nas dietas para alevinos de tilápia do Nilo.(AU)

Antiproliferative, genotoxic and mutagenic potential of synthetic chocolate food flavoring / Potencial antiproliferativo, genotóxico e mutagênico do aroma de chocolate sintético para alimentos

Flavoring additives are of great technological importance for the food industry. However, there is little information regarding the toxicological properties of these micro-ingredients, especially at the cellular level. The present study used meristematic root cells of Allium cepa L. to evaluate the toxicity of a liquid, aroma and flavor synthetic chocolate additive, manufactured and widely marketed throughout Brazil and exported to other countries in South America. The flavoring concentrations evaluated were 100.00; 50.00; 25.00; 1.00; 0.50 and 0.25 µL/L, where the highest concentration established was one-hundred times lower than that commercially suggested for use. The concentration 100 µL/L substantially reduced cell division of meristems within 24- and 48-hours exposure. Concentrations from 100.00 to 0.50 µL/L resulted in a significant number of prophases to the detriment of the other phases of cell division, indicating an aneugenic activity, and induced a significant number of cellular changes, with emphasis on micronuclei, nuclear buds and chromosomal breaks. Under the established analysis conditions, with the exception of concentration 0.25 µL/L, the flavoring of chocolate caused cytotoxicity, genotoxicity and mutagenicity to root meristems.

Os aditivos aromatizantes têm grande importância tecnológica para a indústria de alimentos. Contudo, poucas são as informações quanto as propriedades toxicológicas desses microingredientes, especialmente, em nível celular. No presente estudo avaliou-se, sobre as células meristemáticas de raízes de Allium cepa L., a toxicidade de um aditivo sintético líquido de aroma e sabor de chocolate, fabricado e amplamente comercializado em todo Brasil, e exportado para outros países da América do Sul. As concentrações de aromatizante avaliadas foram 100,00; 50,00; 25,00; 1,00; 0,50 e 0,25 µL/L, onde a maior concentração estabelecida foi cem vezes menor que a sugerida comercialmente para uso. Com base na interpretação dos resultados, a concentração 100 µL/L reduziu substancialmente a divisão celular dos meristemas nas 24 e 48 horas de exposição. As concentrações 100,00 a 0,50 µL/L demonstraram número significativo de prófases em detrimento as outras fases da divisão celular, indicando ação aneugênica, e induziram número significativo de alterações celulares, com ênfase a micronúcleos, broto nucleares e quebras cromossômicas. Nas condições de análises estabelecidas, com exceção a concentração 0,25 µL/L, o aromatizante de chocolate causou citotoxicidade, genotoxicidade e mutagenicidade aos meristemas radiculares.

Meta-Analysis of Butyric Acid: a Performance-Enhancing Additive to Replace Antibiotics for Broiler Chickens

Butyric acid has been studied and utilized intensively in broiler chicken production in order to substitute growth-promoting antibiotics. However, the comprehensive literature on this topic makes it difficult to understand overall results, since there is a noticeable number of studies with conflicting conclusions. Although several research studies have shown that butyric acid may increment broiler chicken's performance, several other studies show the opposite. This work aimed to organize information to understand, through a meta-analysis, whether butyric acid can be used as a performance-enhancing additive for broiler chickens, and whether it can replace growth-promoting antibiotics. It was clear from the results that the effect of butyric acid depends on the microbiological challenge that broilers receive. When broilers are raised without health challenge, butyric acid and even antibiotics do not influence growth performance. However, when broilers are challenged, butyric acid provided an increase in weight gain and a significant improvement in feed conversion, matching the results of antibiotics. We conclude that butyric acid improves broiler performance and can be used to replace growth-promoting antibiotics.(AU)

Hydroalcoholic extract of jabuticaba peel in the diet of betta fish / Extrato hidroalcoólico de casca de jabuticaba na dieta de peixe betta

The objective of this study was to evaluate the effects of jabuticaba (Plinia cauliflora) peel extract on the diets of female blue Betta splendens concerning the level of digestive enzymes, liver metabolism, and antioxidant activity. The sample constituted 150 individuals subdivided into five groups in tripli-cate, totaling 10 fish per 20-liter experimental unit. Commercial diets (40.88% crude protein (CP) and 4374.8 Kcal•kg-1v) were added to hydroalcoholic jabuticaba peel extract (EHJ) at concentrations of 0 (control), 0.5, 1.0, 1.5, and 2.0 g•kg-1. The diets were provided twice a day, until apparent satiety, for 21 days. Fish mortality was not observed during the study. Growth indices did not show any significant differences, apart from feed conversion. The use of the extract promoted an increase in the luminosity of the fish; however, there was no statistical difference in chromaticity a* and b*. A decrease in the activity of SOD on the skin of fish fed with diets of 1.5 and 2 g kg-1 EHJ was observed in comparison to the other diets. There was no change in catalase (CAT) activity among the experimental treatments. It is concluded that the use of 2 g•kg-1 EHJ has an antioxidant effect that reflects the greater luminosity of blue female Betta splendens.(AU)

O objetivo deste estudo foi avaliar os efeitos do extrato hidroalcoólico de casca de jabuticaba em die-tas de Bettasplendes azuis em relação ao conteúdo de enzimas digestivas, ao metabolismo hepático e à atividade antioxidante. Foram utilizados 150 indivíduos divididos em cinco grupos em triplicatas, totalizando dez peixes por unidade experimental de 20 L. Às dietas comerciais (40,88% PB e 4.374,8 Kcal kg-1), foi acrescido extrato hidroalcoólico de casca de jabuticaba (EHJ) nas seguintes concentra-ções: controle; 0,5; 1; 1,5; e 2 g•kg-1). A ração foi fornecida aos exemplares duas vezes ao dia, até a saciedade aparente, por 21 dias. Não foi registrada a mortalidade de peixes durante o ensaio, bem como diferença significativa nos índices de crescimento, com exceção da conversão alimentar. A utili-zação do extrato aumentou a luminosidade dos peixes, porém não se verificou diferença estatística na cromaticidade a* e b*. Quanto ao superóxido dismutase, diminuiu-se sua atividade na pele do grupo alimentado com dietas acrescidas de 1,5 e 2 g•kg-1 EHJ em comparação com as demais. O último item avaliado foi a catalase, cuja atividade não se alterou no período estudado. Concluiu-se, portanto, que a utilização de 2 g•kg-1 EHJ proporciona efeito antioxidante, que se reflete em maior luminosidade de Bettasplendes azuis.(AU)

Inclusão da ractopamina na nutrição de peixes: revisão de literatura / Inclusion of ractopamine in fish nutrition: literature review / Inclusión de ractopamina en nutrición de peces: revisión de literatura

A demanda da população mundial por produtos aquáticos esta se incrementando, enquanto que a produção da pesca extrativa reduzindo, alcançando em muitos casos, seu máximo potencial produtivo. Como consequência, não será possível em curto prazo, sustentar o fornecimento de produtos aquáticos, direcionado a uma população que constantemente cresce e demanda pescados. O setor produtivo segue a tendência atual de outros sistemas de produção animal, os quais vêm buscando o aumento da produtividade, de maneira sustentável, do ponto de vista econômico e ambiental, requerendo, principalmente, o aporte da nutrição para contribuir com essa tendência. Os estudos com os aditivos adicionados a dieta dos animais de cativeiro é uma estratégia que tem demonstrado alto potencial para sua inclusão na aquicultura, havendo a possibilidade de um aumento nos índices produtivos e/ou melhora na qualidade do produto para o consumidor. A ractopamina é um aditivo classificado como um agonista beta-adrenérgico e seu mecanismo de ação esta associado com efeitos sobre o metabolismo dos peixes que diminuem o acúmulo de gorduras, por meio da inibição da lipogêneses e estimulo da lipólise, e por mecanismos que favorecem a síntese de proteínas muscular. Os estudos realizados até o momento comprovam que existem alterações metabólicas nos peixes, embora, não se tem encontrado, em todos os estudos, diferenças significativas nos índices zootécnicos, para assim, estabelecer seu uso na indústria. A realização de mais pesquisas é necessária para o melhor entendimento da ractopamina na alimentação dos peixes, sobretudo, no entendimento dos receptores e mecanismos de ação dos peixes.(AU)

The demand of the global population for aquatic products is increasing while the production of extractive fisheries is reducing, and, in many cases, even reaching its maximum productive potential. As a consequence, it will not be possible in the short term to sustain the supply of aquatic products aimed at a population in constant growth and in demand for fish. The productive sector follows the current trend of other animal production systems, which have been seeking to sustainably increase productivity from an economic and environmental point of view, mainly requiring the contribution of nutrition to this trend. Studies with additives to the diet of captive animals is a strategy that has shown high potential for inclusion in aquaculture, with the possibility of an increase in production rates and/or improvement in the quality of the product for the consumer. Ractopamine is an additive classified as a beta-adrenergic agonist and its mechanism of action is associated with effects on fish metabolism that reduce the accumulation of fats through the inhibition of lipogenesis and stimulation of lipolysis, and by mechanisms that favor the synthesis of muscle protein. The studies carried out so far prove that there are metabolic changes in fish, although no significant differences have been found in zootechnical indexes in order to establish its use in the industry. Further research is required for a better understanding of ractopamine in fish nutrition, especially in understanding the receptors and mechanisms of action in fish.(AU)

La demanda de la población mundial por productos acuáticos va en aumento, mientras que la producción de la pesca extractiva se reduce, alcanzando, en muchos casos, su máximo potencial productivo. Como consecuencia, no será posible en corto plazo sostener el suministro de productos acuáticos, dirigidos a una población que crece constantemente y demanda pescado. El sector productivo sigue la tendencia actual de otros sistemas de producción animal, que han venido buscando incrementar la productividad, de manera sostenible, desde el punto de vista económico y ambiental, requiriendo, principalmente, del aporte de la nutrición para contribuir a esa tendencia. Los estudios con aditivos agregados a la dieta de animales en cautiverio es una estrategia que ha mostrado un alto potencial para su inclusión en la acuicultura, con posibilidad de incremento en los índices de producción y/o mejora en la calidad del producto para el consumidor. La ractopamina es un aditivo clasificado como agonista beta-adrenérgico y su mecanismo de acción está asociado con efectos sobre el metabolismo de los peces que reducen la acumulación de grasas, a través de la inhibición de la lipogénesis y estimulación del lipólisis, y por mecanismos que favorecen la síntesis de proteínas musculares. Los estudios realizados hasta el momento prueban que existen cambios metabólicos en los peces, aunque en todos los estudios no se han encontrado diferencias significativas en los índices zootécnicos, con el fin de establecer su uso en la industria. Se necesita más investigación para comprender mejor la ractopamina en la nutrición de los peces, especialmente para comprender los receptores y los mecanismos de acción en los peces.(AU)

Growth performance and meat quality of feedlot steers fed diets with or without natural feed additive

The objective of this study was to evaluate the growth performance and meat quality of feedlot Aberdeen Angus steers fed high-concentrate diets with or without a natural feed additive composed of a mixture of yeasts and essential oils (EO). A completely randomized design with two diets (with or without natural feed additive) and 12 replicates was used. Twenty-four steers with initial shrunk body weight of 402.62±48.2 kg and average age of 18±2.0 months were used. Steers were fed ad libitum a diet containing 777.3 g of concentrate/kg dry matter (DM) and 222.7 g of corn silage/kg DM for 74 days. The mixture of yeast and EO was supplied at the rate of 10.0 and 0.117 g/animal/day, respectively. Average daily weight gain and feed efficiency in the adaptation period was greater in animals fed natural feed additive; however, there was no difference for the total experimental period. Dry matter intake, carcass weight, carcass yield, proportion of carcass bone, carcass muscle + fat:bone ratio, round thickness, and arm length were not altered by treatments. The inclusion of a natural feed additive in the diet increased the cooling loss (0.98 vs. 1.25%), proportion of carcass muscle (51.32 vs. 54.56%), carcass muscle:fat ratio (1.70 vs. 2.11%), leg length (68.79 vs. 70.71 cm), and arm perimeter (36.70 vs. 37.88 cm) and reduced the proportion of carcass fat (30.17 vs. 25.92%). Carcass length was greater in animals fed the diet with a natural feed additive. Meat color, texture, and marbling were not altered by treatments. The addition of natural feed additive to high concentrate diets does not alter the productive performance of feedlot Aberdeen Angus steers, although it can increase the proportion of lean meat of carcasses.(AU)

Addition of a blend of exogenous enzymes to broiler chickens diets: impacts on performance and production costs / Adição de uma mistura de enzimas exógenas a dietas de frangos de corte: impactos no desempenho e custos de produção

Broiler diets are based on corn, soybean and wheat production; however, some protein ingredients have many antinutritional factors and low digestibility. The objective of this study was to add a blend of exogenous enzymes to the feed with low nutritional value for broilers to reduce production costs and improve digestibility while maintaining good zootechnical performance. The experimental design was completely randomized, including three treatments with five replications (n=15) each: a) positive control (PC), diet calculated for males with average performance; b) negative control + exogenous enzymes (NC+EE), minimum nutrient diet according to the requirements of the production phase, and the enzymatic blend was added; and c) negative control (NC), minimum levels of nutrients for each phase. At 21 days, the PC group showed greater weight gain and lower feed conversion than the NC (P<0.05). At 42 days, PC had lower feed intake than NC (P=0.040), while lower feed conversion was observed in groups PC and NC+EE than NC (P=0.001). The production efficiency index was higher in the PC treatment, but the NC+EE treatment was higher than the NC (P=0.001). Considering production costs and body weight, we found that NC+EE birds had greater profitability. Therefore, we conclude that the blend of exogenous enzymes added to a diet with minimal nutritional levels has practical application in the broiler production system.(AU)

As dietas de frangos de corte são baseadas na produção de milho, soja e trigo; no entanto, alguns ingredientes proteicos possuem muitos fatores antinutricionais e baixa digestibilidade. O objetivo deste estudo foi adicionar à ração uma mistura de enzimas exógenas com baixo valor nutricional para frangos de corte para reduzir os custos de produção e melhorar a digestibilidade, mantendo o bom desempenho zootécnico. O delineamento experimental foi inteiramente casualizado, incluindo três tratamentos com cinco repetições (n=15) cada: a) controle positivo (PC), dieta calculada para machos com desempenho médio; b) controle negativo + enzimas exógenas (CN+EE), dieta mínima de nutrientes de acordo com as exigências da fase de produção, e foi adicionada a mistura enzimática; c) controle negativo (CN), teores mínimos de nutrientes para cada fase. Aos 21 dias, o grupo PC apresentou maior ganho de peso e menor conversão alimentar que o NC (P<0,05). Aos 42 dias, PC apresentou menor consumo de ração que NC (P=0,040), enquanto foi observada menor conversão alimentar nos grupos PC e NC+EE que NC (P=0,001). O índice de eficiência de produção foi maior no tratamento PC, mas o tratamento NC+EE foi maior que o NC (P=0,001). Considerando os custos de produção e peso corporal, verificamos que as aves NC+EE tiveram maior rentabilidade. Portanto, concluímos que a mistura de enzimas exógenas adicionada a uma dieta com níveis nutricionais mínimos tem aplicação prática no sistema de produção de frangos de corte.(AU)

Thermogenic oils as a substitute forractopamine in the production of heavy pigs / Óleos termogênicos em substituição a ractopamina na produção de suínos em fase de pós-terminação

This study aimed to assess the effects of thermogenic oils (safflower and coconut oils) as a replacement for ractopamine in heavy pig diets. A total of 24 mix-breed barrows with an average weight of 98.70 ± 1.63 kg were distributed in a randomized block design with four treatments and six replicates. Treatments were as follows: basal diet, modified basal diet + 10 ppm ractopamine, basal diet + safflower oil, and basal diet + coconut oil. Animal performance, organ weights, meat quality, carcass traits, and economic viability were determined. Data were analyzed using Duncan's test at the 5% significance level. The safflower oil diet resulted in the highest carcass meat and ham weights, whereas the coconut oil diet provided the highest loin eye area and the lowest fat area, resulting in the highest meat/fat ratio. Analysis of economic viability indicators revealed that vegetable oil treatments differed significantly from other treatments in feed cost, feed cost per kilogram of live weight, economic viability index, and cost index, given that oil inclusion increased the price of diets. Supplementation of heavy pig diets with thermogenic oils is a viable alternative to enhance lean meat production, but its use depends on market availability and product price.(AU)

Este estudo visou avaliar os efeitos dos óleos termogênicos (óleos de cártamo e de coco) como substitutos da racto-pamina em dietas de suínos pesados. Um total de 24 suínos machos castrados com um peso médio de 98,70 ± 1,63 kg foram distribuídos em um modelo de blocos aleatorizados com quatro tratamentos e seis repetições. Os tratamentos foram os seguintes: dieta basal (RB), RB modificada + 10 ppm de ractopamina, RB + óleo de cártamo, e RB + óleo de coco. Foram determinados o desempenho animal, pesos dos órgãos, qualidade da carne, características da carcaça, e viabilidade económica. Os dados foram analisados utilizando o teste de Duncan ao nível de 5% de significância. A dieta de óleo de Cártamo resultou na maior quan-tidade de carne de carcaça e pesos de pernil, enquanto que a dieta de óleo de coco forneceu a maior área do olho do lombo e a menor área de gordura, resultando na maior relação carne/gordura. A análise dos indicadores de viabilidade económica reve-lou que os tratamentos com óleo vegetal diferiram significativamente de outros tratamentos no custo da alimentação, custo da alimentação por quilograma de peso vivo, índice de viabilidade económica, e índice de custo, dado que a inclusão do óleo aumentou o preço das dietas. A suplementação de dietas de suínos pesados com óleos termogênicos é uma alternativa viável para aumentar a produção de carne magra, mas a sua utilização depende da disponibilidade no mercado e do preço do produto.(AU)