Fish functional trophic groups in headwater karst streams from the Upper Paraguay River basin

Data obtained by direct observation of organisms in their natural habitats can provide valuable contributions regarding intra- and inter-specific interactions, as well as spatial distribution and trophic relationships. However, relatively few such data are available for the Neotropical ichthyofauna relative to the great species diversity of this region. We present data on the ichthyofauna in karst environments of the Serra da Bodoquena, Upper Paraguay River basin regarding their categorization into functional trophic groups. We used direct observations that focused on the most frequent feeding tactics and their spatial (vertical and horizontal) distribution in the channel. We observed 83 fish species in 17 functional trophic groups. The greatest species richness was concentrated in the Characidae and Loricariidae in the categories Diurnal Backwater Drift Feeders and Grazers, respectively. Regarding horizontal depth stratification, we found a positive relationship between the association of small fish with the shallow marginal habitats. This work represents a contribution to a region known for its high tourist potential and to the important diversity of the entire ichthyofauna of the Upper Paraguay basin region that requires proper conservation strategies for sustaining these species.(AU)

Dados obtidos pela observação direta dos organismos em seus hábitats naturais podem fornecer valiosas contribuições com relação a interações intra e inter-específicas, além de distribuição espacial e relações tróficas. Entretanto, relativamente poucos dados estão disponíveis no que diz respeito à ictiofauna neotropical dada à grande diversidade dessa região. Apresentamos dados sobre a ictiofauna em ambientes cársticos da Serra da Bodoquena, bacia do alto rio Paraguai e a categorização das mesmas em grupos tróficos funcionais baseada em observações diretas relacionadas às táticas alimentares mais frequentes e à sua distribuição espacial (vertical e horizontal) no canal. Assim sendo, observamos 83 espécies de peixes alocadas em 17 grupos tróficos funcionais. A maior riqueza de espécies concentrou-se nas famílias Characidae e Loricariidae, abrangendo as categorias Catadores Diurnos de Itens Arrastados pela Corrente e Pastadores, respectivamente. Com relação à estratificação horizontal, encontramos a relação positiva entre a associação de peixes de pequeno porte com relação aos hábitats marginais. Esse trabalho representa uma contribuição a uma região conhecida pelo seu alto potencial turístico e à importante diversidade da ictiofauna da região da bacia do alto Paraguai que requer estratégias de conservação adequadas para sustentar essas espécies.(AU)

Intra-annual colonization of Chironomidae on leaf litter in a Brazilian Cerrado stream

In low-order streams, the processing of allochthonous leaf litter is essential in the carbon/energy flow dynamics. Benthic macroinvertebrates, such as chironomids, play critical roles in the breakdown of allochthonous materials, because their larvae take part in intricate trophic networks and have varied trophic ecologies. We evaluated the effects of intra-annual variability on the input of allochthonous leaf litter, and the interactions of leaf-detritus on the succession of Chironomidae assemblages in the dry, rainy, and transition seasons (rainy-dry and dry-rainy). The study took place in a stream in the Brazilian Cerrado. Leaves were incubated in the stream to ascertain the colonization process by Chironomidae and the loss of leaf litter mass after 90 days. Functional feeding groups (FFG) were less rich and less abundant in the dry and dry-rainy seasons, than in the other seasons. The FFG composition of Chironomidae demonstrated that temporal variation between seasons was affected by the exposure time of the leaf-detritus in the stream, and there was more segregation during the dry and rainy seasons. In conclusion, the colonization of leaf-detritus by Chironomidae larvae depended on how long allochthonous plant material remained in the stream, and the variability of the organic matter dynamics input into the stream.

Effect of Hydroponic Wheat Sprout on the Growth Performance, Carcass Characteristics, and Lipid Profiles of Broilers

The aim of present study was to understand the dietary effect of hydroponic wheat sprout (WS) on the growth performance, carcass characteristics and lipid profiles of broiler chickens. Two independent feeding trials were conducted using Cobb 500 broiler DOC for the period of 0 to 32 days. In the first trail, 264 DOC were allocated into 4 treatments having 3 replications per treatment and 22 birds per replication to find out the suitable inclusion level of WS. In second trial, 384 broiler DOC were allocated into 4 treatments having 6 replications per treatment and 16 birds in each replication to assess the functional quality of WS. In first trial, the body weight (1692.33 g/bird), body weight gain (1644.96 g/bird) and FCR (1.47) were significantly (p<0.05) improved in the birds fed 50 g/kg WS compared to the other dietary groups but feed intake showed no significant (p<0.05) differences. Likewise, in second trial the birds fed commercial feed showed significantly (p<0.05) higher body weight (1649.50 g/bird) and weight gain (1601.88 g/bird) compared to the birds fed 50 g/kg WS. Feed intake and FCR showed no significance differences. Total cholesterol and triglycerides were significantly (p<0.05) lower (85.5 mg/dl and 84.32 mg/dl, respectively) however HDL was higher (111.86 mg/dl) in the birds received 50 g/kg WS. Taken all together, it can be concluded that the inclusion of 50 g/kg WS in broiler had positive effects on growth performance and blood lipid profile in commercial broilers.(AU)

Effect of dietary protein and genetic line of Litopenaeus vannamei on its hepatopancreatic microbiota

Host genetics and diet can exert an influence on microbiota and, therefore, on feeding efficiency. This study evaluated the effect of genetic line (fast-growth and high-resistance) in Pacific white shrimp (Litopenaeus vannamei) on the hepatopancreatic microbiota and its association with the feeding efficiency in shrimp fed with diets containing different protein sources. Shrimp (2.08 ± 0.06 g) from each genetic line were fed for 36 days with two dietary treatments (animal and vegetable protein). Each of the four groups was sampled, and the hepatopancreatic metagenome was amplified using specific primers for the variable V4 region of the 16S rRNA gene. The PCR product was sequenced on the MiSeq platform. Nineteen bacterial phyla were detected, of which Proteobacteria was the most abundant (51.0 72.5 %), Bacteroidetes (3.6 23.3 %), Firmicutes (4.2 13.7 %), Actinobacteria (1.9 12.1 %), and Planctomycetes (1.3 9.5 %). Diet was the most influential factor in the taxonomic composition of the microbiota, while genetic line was not a strong influential factor. The results suggest that the taxonomic profile of the bacteria colonizing shrimp hepatopancreas was determined by the diet consumed, similar to what occurs in the intestine. Shrimp in the fast-growth line had greater feeding efficiency regardless of the diet supplied. Finally, the results suggest that Proteobacteria influenced (p < 0.05) the feeding efficiency of shrimp fed with a vegetable diet. Nevertheless, further studies are required to explore how shrimp genetic linediet interaction influences microbiota for probiotic development and functional food formulation for farmed shrimp according to the genetic line.(AU)

Effect of dietary protein and genetic line of Litopenaeus vannamei on its hepatopancreatic microbiota

Host genetics and diet can exert an influence on microbiota and, therefore, on feeding efficiency. This study evaluated the effect of genetic line (fast-growth and high-resistance) in Pacific white shrimp (Litopenaeus vannamei) on the hepatopancreatic microbiota and its association with the feeding efficiency in shrimp fed with diets containing different protein sources. Shrimp (2.08 ± 0.06 g) from each genetic line were fed for 36 days with two dietary treatments (animal and vegetable protein). Each of the four groups was sampled, and the hepatopancreatic metagenome was amplified using specific primers for the variable V4 region of the 16S rRNA gene. The PCR product was sequenced on the MiSeq platform. Nineteen bacterial phyla were detected, of which Proteobacteria was the most abundant (51.0 72.5 %), Bacteroidetes (3.6 23.3 %), Firmicutes (4.2 13.7 %), Actinobacteria (1.9 12.1 %), and Planctomycetes (1.3 9.5 %). Diet was the most influential factor in the taxonomic composition of the microbiota, while genetic line was not a strong influential factor. The results suggest that the taxonomic profile of the bacteria colonizing shrimp hepatopancreas was determined by the diet consumed, similar to what occurs in the intestine. Shrimp in the fast-growth line had greater feeding efficiency regardless of the diet supplied. Finally, the results suggest that Proteobacteria influenced (p < 0.05) the feeding efficiency of shrimp fed with a vegetable diet. Nevertheless, further studies are required to explore how shrimp genetic linediet interaction influences microbiota for probiotic development and functional food formulation for farmed shrimp according to the genetic line.

Ecological studies of mayflies (Insecta, Ephemeroptera): Can sampling effort be reduced without losing essential taxonomic and ecological information? / Estudos ecológicos com Ephemeroptera (Insecta): O esforço amostral pode ser reduzido sem perder informações ecológicas e taxonômicas?

The present study evaluated the potential for the reduction of sampling effort in studies of ephemeropteran nymphs in Brazilian Amazon streams, Pará State, Brazil, without the loss of ecological information (species composition, abundance, and richness), and the congruence of different levels of taxonomic resolution (morphospecies, genus, family and functional group). Test groups of 15, 10 and five subsamples were selected from the 20 subsamples collected per stream (40 streams sampled), and were compared in terms of their species richness and abundance (ANOVA), and composition (Procrustes). Taxonomic resolution was also analyzed in Procrustes. Species abundance (F(3, 156) = 25.426; p 0.001) and richness (F(3, 156) = 13.866, p 0.001) varied significantly among sample groups, while the results of the 15-S group were statistically similar, in both cases, to those of the 20-S group. A similar pattern was found for species composition. The genus-level taxonomic resolution produced results 99% similar to those found for the species-level data. The results indicate that the reduction in sampling effort from 20 to 15 subsamples per site and a genus-level taxonomic resolution would not affect the reliability of analyses significantly. A reduction of five samples per site would result in a decrease of effort in the field and the amount of material to be processed, reducing laboratory time. In addition to a reduction in the time and resources needed to identify specimens, the adoption of a genus-level taxonomic resolution could help minimize errors of under- or over-estimation in the processing of the results.(AU)

O presente estudo avaliou o potencial para redução do esforço amostral em estudos com ninfas de Ephemeroptera em igarapés amazônicos, no estado do Pará, Brasil, sem perder informações ecológicas (composição de espécies, abundância e riqueza), além de verificar se existe congruência entre diferentes níveis de resolução taxonômica (morfoespécie, gênero, família e grupo funcional). Grupos reduzidos de 15, 10 e cinco subamostras de um controle de 20 amostras de cada um dos 40 igarapés amostrados, foram comparados quanto a riqueza de táxons e abundância (ANOVA) e composição (Procrustes). A resolução taxonômica também foi avaliada através do Procrustes. A abundância (F(3, 156) = 25,426; p 0,001) e riqueza (F(3, 156) = 13,866, p 0,001) variaram significativamente entre os grupos de amostras, porém, os resultados tanto de riqueza quanto de abundância dos grupos 15-S foram estatisticamente similares aos de 20-S. O mesmo padrão foi encontrado para riqueza de espécies. A resolução taxonômica a nível de gênero obteve 99% de congruência com a de morfoespécie. Esses resultados indicam que a diminuição de 20 subamostras para 15, e a redução da identificação de morfoespécie para gênero não afetaria a significância das análises. A redução de cinco amostras por local de coleta poderia resultar em uma diminuição do esforço em campo e do material para ser processado em laboratório, reduzindo o tempo de triagem e identificação. Ainda, para reduzir tempo e recursos financeiros gastos para coleta e identificação dos organismos, a identificação apenas a nível genérico poderia minimizar erros de sub ou super estimativa no processamento dos resultados.(AU)

Perfil glicêmico: efeito da estreptozotocina e do yacon (Smallanthus sonchifolius) em ratos Wistar / Glycemic profile: effect of estreptozotocin and yacon (Smallanthus sonchifolius) in Wistar rats

Yacon é considerado um alimento funcional, que tem entre suas propriedades capacidadehipoglicêmica. O objetivo deste estudo foi avaliar o efeito modulador do yaconno perfil glicêmico de ratos Wistar. O experimento teve duração de 60 dias com 32animais. A matriz alimentar desidratada (yacon pó / YP) foi adicionada à dieta dos gruposque receberam intervenção na dose de 7,5% de frutanos tipo inulina (FTI). As variáveisanalisadas foram: composição centesimal e conteúdo de frutanos tipo inulina, ganhode peso, peso relativo do ceco (PRC), consumo alimentar, coeficiente de eficiênciaalimentar e glicemia. Todas as análises seguiram os protocolos da AOAC. Na análiseestatística foram utilizados os seguintes testes: ANOVA ou Kruskal Wallis seguidosde testes de comparação de médias, teste t e teste t pareado. O nível de significânciaestatística foi p <0,05 para todas as análises. Este estudo foi aprovado pelo Comitê deÉtica em Uso de Animais da Universidade Federal de Alfenas, protocolo nº. 698/2015.Os resultados mostraram que no grupo controle que recebeu YP, houve uma reduçãosignificativa nos valores glicêmicos. Em todos os grupos que receberam YP houve umaumento significativo do ceco, como esperado. O desenvolvimento de diabetes nãofoi observado com o uso de estreptozotocina associado a 35% de sacarose. Portanto,a avaliação do efeito do yacon sobre a hipoglicemia foi prejudicada. Isto sugere queestudos nesta linha sejam encorajados para elucidações adicionais.

Yacon is considered a functional food, which has among its properties, and has ahypoglycemic capacity. The aim of this study was to evaluate the modulatory effectof yacon in the glycemic profile of Wistar rats. The experiment lasted 60 days with32 animals. Was used the dehydrated food matrix (yacon powder / YP) added tothe diet of the groups that received intervention in the dose of 7.5% of inulin typefructan (ITF). The analyzed variables were: centesimal composition and content ofinulin type frutans, weight gain, relative weight of cecum (RWC), food consumption,coefficient of food efficiency and glycemia. All analyzes followed the AOAC protocols.In the statistical analysis, the following tests were used: ANOVA or Kruskal Wallisfollowed by comparison tests of means, t test and paired t test. The level of statisticalsignificance was p <0.05 for all analyzes. This study was approved by the EthicsCommittee on the Use of Animals of the Federal University of Alfenas, protocol nº698/2015. The results showed that in the control group receiving YP, was a significantreduction in glycemic values. In all groups receiving YP there was a significantincrease of cecum, as expected. The development of diabetes was not observeddue to the use of streptozotocin with 35% sucrose. Therefore, the evaluation of theeffect of yacon on hypoglycaemia has been impaired. This suggests that studies inthis line are encouraged for further elucidations.

Perfil glicêmico: efeito da estreptozotocina e do yacon (Smallanthus sonchifolius) em ratos Wistar / Glycemic profile: effect of estreptozotocin and yacon (Smallanthus sonchifolius) in Wistar rats

Yacon é considerado um alimento funcional, que tem entre suas propriedades capacidadehipoglicêmica. O objetivo deste estudo foi avaliar o efeito modulador do yaconno perfil glicêmico de ratos Wistar. O experimento teve duração de 60 dias com 32animais. A matriz alimentar desidratada (yacon pó / YP) foi adicionada à dieta dos gruposque receberam intervenção na dose de 7,5% de frutanos tipo inulina (FTI). As variáveisanalisadas foram: composição centesimal e conteúdo de frutanos tipo inulina, ganhode peso, peso relativo do ceco (PRC), consumo alimentar, coeficiente de eficiênciaalimentar e glicemia. Todas as análises seguiram os protocolos da AOAC. Na análiseestatística foram utilizados os seguintes testes: ANOVA ou Kruskal Wallis seguidosde testes de comparação de médias, teste t e teste t pareado. O nível de significânciaestatística foi p <0,05 para todas as análises. Este estudo foi aprovado pelo Comitê deÉtica em Uso de Animais da Universidade Federal de Alfenas, protocolo nº. 698/2015.Os resultados mostraram que no grupo controle que recebeu YP, houve uma reduçãosignificativa nos valores glicêmicos. Em todos os grupos que receberam YP houve umaumento significativo do ceco, como esperado. O desenvolvimento de diabetes nãofoi observado com o uso de estreptozotocina associado a 35% de sacarose. Portanto,a avaliação do efeito do yacon sobre a hipoglicemia foi prejudicada. Isto sugere queestudos nesta linha sejam encorajados para elucidações adicionais.(AU)

Yacon is considered a functional food, which has among its properties, and has ahypoglycemic capacity. The aim of this study was to evaluate the modulatory effectof yacon in the glycemic profile of Wistar rats. The experiment lasted 60 days with32 animals. Was used the dehydrated food matrix (yacon powder / YP) added tothe diet of the groups that received intervention in the dose of 7.5% of inulin typefructan (ITF). The analyzed variables were: centesimal composition and content ofinulin type frutans, weight gain, relative weight of cecum (RWC), food consumption,coefficient of food efficiency and glycemia. All analyzes followed the AOAC protocols.In the statistical analysis, the following tests were used: ANOVA or Kruskal Wallisfollowed by comparison tests of means, t test and paired t test. The level of statisticalsignificance was p <0.05 for all analyzes. This study was approved by the EthicsCommittee on the Use of Animals of the Federal University of Alfenas, protocol nº698/2015. The results showed that in the control group receiving YP, was a significantreduction in glycemic values. In all groups receiving YP there was a significantincrease of cecum, as expected. The development of diabetes was not observeddue to the use of streptozotocin with 35% sucrose. Therefore, the evaluation of theeffect of yacon on hypoglycaemia has been impaired. This suggests that studies inthis line are encouraged for further elucidations.(AU)

A closer look at the main actors of Neotropical floodplain food webs: functional classification and niche overlap of dominant benthic invertebrates in a floodplain lake of Paraná River

Functional classification of animals is necessary to enhance the predictive power of food web models. However, while there is a large database for functional classification of benthic invertebrates (Functional Feeding Groups, FFG) in the temperate zone, the attribution of individual species of riverine invertebrates is still in its infancies in the Neotropical Region. Different authors hypothesized that diet breadth was larger in the Tropics, however detailed analysis are scarce. In the present study we aimed at classifying dominant benthic taxa of the Middle Paraná River floodplain (Argentina) into trophic guilds by diet and niche overlap analyses. We sampled twelve taxa of benthic invertebrates from a floodplain lake during low water season and performed a gut content analysis as a baseline for FFG classification. We also used available diet information of other common taxa for statistical analysis. Then, we compared the variance of niche overlap, using Pianka's index, with that of simulated null model. After that we grouped taxa using Morisita similarity index with a threshold of 0.6 and compared niche overlap with null models within and between FFGs. Observed variance of niche overlap was greater than expected by chance, confirming the presence of FFGs among analyzed taxa. Considering trophic similarity of species, we identified four FFGs: collectors, omnivores, herbivores and predators. Niche overlap was greater than expected by stochastic null models within FFGs, and smaller between FFGs. Nearly one third of analyzed taxa were classified in a different FFG than their congeners of the Holarctic region. This result indicates that classifications performed in the Holarctic region should be used with care in the Neotropical region, even in subtropical systems.(AU)

A closer look at the main actors of Neotropical floodplain food webs: functional classification and niche overlap of dominant benthic invertebrates in a floodplain lake of Paraná River

Functional classification of animals is necessary to enhance the predictive power of food web models. However, while there is a large database for functional classification of benthic invertebrates (Functional Feeding Groups, FFG) in the temperate zone, the attribution of individual species of riverine invertebrates is still in its infancies in the Neotropical Region. Different authors hypothesized that diet breadth was larger in the Tropics, however detailed analysis are scarce. In the present study we aimed at classifying dominant benthic taxa of the Middle Paraná River floodplain (Argentina) into trophic guilds by diet and niche overlap analyses. We sampled twelve taxa of benthic invertebrates from a floodplain lake during low water season and performed a gut content analysis as a baseline for FFG classification. We also used available diet information of other common taxa for statistical analysis. Then, we compared the variance of niche overlap, using Pianka's index, with that of simulated null model. After that we grouped taxa using Morisita similarity index with a threshold of 0.6 and compared niche overlap with null models within and between FFGs. Observed variance of niche overlap was greater than expected by chance, confirming the presence of FFGs among analyzed taxa. Considering trophic similarity of species, we identified four FFGs: collectors, omnivores, herbivores and predators. Niche overlap was greater than expected by stochastic null models within FFGs, and smaller between FFGs. Nearly one third of analyzed taxa were classified in a different FFG than their congeners of the Holarctic region. This result indicates that classifications performed in the Holarctic region should be used with care in the Neotropical region, even in subtropical systems.

A closer look at the main actors of Neotropical floodplain food webs: functional classification and niche overlap of dominant benthic invertebrates in a floodplain lake of Paraná River

ABSTRACT Functional classification of animals is necessary to enhance the predictive power of food web models. However, while there is a large database for functional classification of benthic invertebrates (Functional Feeding Groups, FFG) in the temperate zone, the attribution of individual species of riverine invertebrates is still in its infancies in the Neotropical Region. Different authors hypothesized that diet breadth was larger in the Tropics, however detailed analysis are scarce. In the present study we aimed at classifying dominant benthic taxa of the Middle Paraná River floodplain (Argentina) into trophic guilds by diet and niche overlap analyses. We sampled twelve taxa of benthic invertebrates from a floodplain lake during low water season and performed a gut content analysis as a baseline for FFG classification. We also used available diet information of other common taxa for statistical analysis. Then, we compared the variance of niche overlap, using Pianka's index, with that of simulated null model. After that we grouped taxa using Morisita similarity index with a threshold of 0.6 and compared niche overlap with null models within and between FFGs. Observed variance of niche overlap was greater than expected by chance, confirming the presence of FFGs among analyzed taxa. Considering trophic similarity of species, we identified four FFGs: collectors, omnivores, herbivores and predators. Niche overlap was greater than expected by stochastic null models within FFGs, and smaller between FFGs. Nearly one third of analyzed taxa were classified in a different FFG than their congeners of the Holarctic region. This result indicates that classifications performed in the Holarctic region should be used with care in the Neotropical region, even in subtropical systems

SUPLEMENTAÇÃO ALIMENTAR COM MICROALGA Chlorella pyrenoidosa EM CABRAS MESTIÇAS E SEUS EFEITOS SOBRE O COMPORTAMENTO INGESTIVO, SEXUAL, SOCIAL E BEM-ESTAR

Apesar da importância das microalgas como alimento funcional na alimentação humana e animal, ainda são raras as informações de um protocolo definido para o uso de microalgas na dieta de caprinos. Objetivou-se com esse estudo avaliar em cabras os efeitos da suplementação por sete dias de doses crescentes de microalga Chlorella pyrenoidosa sobre a resposta fisiológica, comportamento alimentar, social e resposta a sincronização do estro. Foram utilizadas 28 cabras que tiveram o estro sincronização por três injeções de 100g de D- Cloprostenol em intervalos de setes dias. Os animais foram divididos em quatro grupos de sete aos quais receberam durante sete dias um drench oral com 0g, 5g, 10g e 20g de microalga em solução aquosa respectiva a cada grupo. O suplemento foi fornecido quarenta e oito horas após a segunda dose de prostaglandina e terminou vinte e quatro horas após a terceira dosagem. Neste intervalo foram avaliados parâmetros fisiológicos, consumo e aceitação da dieta, comportamento alimentar e social. Após a terceira dose de prostaglandina foi verificada a resposta ao estro e o comportamento sexual utilizando-se um rufião. Os resultados evidenciaram um incremento das sobras alimentares (P < 0,001) nos grupos com microalga sem manifestar alterações do consumo ou no comportamento alimentar e social. Entre os parâmetros fisiológicos, os grupos de microalgas apresentaram uma elevação (P < 0,001) da taxa respiratória nos horários da tarde, período de maior temperatura ambiental. A resposta ao estro e o comportamento sexual foi similar entre os grupos. A utilização da Chlorella como suplemento alimentar representa uma alternativa possível para caprinos.

Despite the importance of microalgae as a functional food in human and animal nutrition, there is still no information on a defined protocol for the use of microalgae in the diet of goats. The aim of this study was to investigate in goats the effects of supplementing increasing doses of the microalgae Chlorella pyrenoidosa for 7 days on the physiological response, feeding and social behavior, as well as the response to estrus synchronization. Twenty-eight goats that had estrus synchronization by three injections of 100g of D-Cloprostenol at intervals of seven days were used and divided into four groups of 7 animals to which an oral drench with respectively 0g, 5g, 10g and 20g was given for seven days of microalgae in aqueous solution. The supplement was given from the second day after the second dose of prostaglandin and ended the day after the third dose. In this interval, physiological parameters, dietary intake and acceptance, feeding and social behavior were evaluated, and after the third dose of prostaglandin, the response to estrus and sexual behavior were verified using a castrated male. The results showed an increase in food orts (P < 0.001) in the groups with microalgae without showing changes for intake, feeding and social behavior. Among the physiological parameters, the microalgae groups showed an increase (P < 0.001) in the respiratory rate in the afternoon hours of higher environmental temperature. The estrus response and sexual behavior were similar between groups. We conclude that the use of Chlorella as a food supplement represents a possible alternative for goats.

Conjugated linoleic acid of dairy foods is affected by cows feeding system and processing of milk

The distribution of conjugated linoleic acid (CLA) in dairy products commercially available in Chile is poorly understood. This study aimed to assess the content of CLA in dairy cow products from Chile and the effect of processing fresh milk into dairy products. Samples of raw milk were categorized into two groups based on the animal feeding system utilized by the dairy farm: 1) grazing based systems (Los Lagos region); and 2) housing systems using total mixed ration (TMR) diets (Los Angeles region). Simultaneously, commercial samples of condensed milk, powdered milk, butter and Gouda cheese were analyzed. Furthermore, samples of raw milk and processed products (powdered and sweetened condensed milk) were also analyzed. Dairy farms based on grazing systems had higher levels of CLA in raw milk than TMR farms. In addition, average values of CLA were 1.72 g 100 g1 of total fatty acids, in spring milk in the Los Lagos region, and 0.42 g 100 g1 in summer milk, in the Los Angeles region. Similarly, the CLA content of dairy products was higher than that of raw milk. Milk processing affected the transferring of CLA from fresh milk into the final products. Sweetened condensed milk presented lower CLA values than raw and powdered milk. In conclusion, this study indicates the importance of the production systems to the CLA content as well as the effects of milk processing into dairy products. To sum up, more research is needed to elucidate the exact effect of the processing conditions of dairy products on the CLA content.

Conjugated linoleic acid of dairy foods is affected by cows feeding system and processing of milk

The distribution of conjugated linoleic acid (CLA) in dairy products commercially available in Chile is poorly understood. This study aimed to assess the content of CLA in dairy cow products from Chile and the effect of processing fresh milk into dairy products. Samples of raw milk were categorized into two groups based on the animal feeding system utilized by the dairy farm: 1) grazing based systems (Los Lagos region); and 2) housing systems using total mixed ration (TMR) diets (Los Angeles region). Simultaneously, commercial samples of condensed milk, powdered milk, butter and Gouda cheese were analyzed. Furthermore, samples of raw milk and processed products (powdered and sweetened condensed milk) were also analyzed. Dairy farms based on grazing systems had higher levels of CLA in raw milk than TMR farms. In addition, average values of CLA were 1.72 g 100 g1 of total fatty acids, in spring milk in the Los Lagos region, and 0.42 g 100 g1 in summer milk, in the Los Angeles region. Similarly, the CLA content of dairy products was higher than that of raw milk. Milk processing affected the transferring of CLA from fresh milk into the final products. Sweetened condensed milk presented lower CLA values than raw and powdered milk. In conclusion, this study indicates the importance of the production systems to the CLA content as well as the effects of milk processing into dairy products. To sum up, more research is needed to elucidate the exact effect of the processing conditions of dairy products on the CLA content.(AU)

The effect of humic acid substances on the thyroid function and structure in lead poisoning

Lead (Pb) is a heavy metal, which adversely affects thyroid gland function and structure. Due to its high molecular weight and abundant functional groups, humic acid substances (HAS) can form chelates with heavy metals. The experiment was conducted to evaluate the prophylactic effect of HAS on thyroid hormone levels and histopathological lesions of laying hens exposed to lead (Pb) poisoning. After a week of adaptation, 192 Lohmann White laying hens (25 weeks of age) were fed one of four diets: a basal diet (BD) or the BD with HAS (0.15%), with Pb (0.3 g/kg), or with both. Experimental groups were replicated in 12 cages, with four hens each. Pb poisoning did not alter triiodothyronine (FT3; 3.22 ± 0.20 ng/dL) or thyroxine (FT4; 0.71 ± 0.08 ng/dL) concentrations, but caused a 167% increase in thyroid stimulating hormone (TSH) concentration. HAS supplementation returned the high TSH levels of hens exposed to Pb poisoning to normal values. Degenerative changes in the epithelial cells of the thyroid gland of the hens exposed to Pb poisoning were evidenced. Connective tissue cells in the interfollicular area and total amount of colloids with partially atrophic follicles were observed. These histopathological findings were less severe when HAS was added to the diet. In conclusion, HAS alleviates the effects of Pb poisoning on thyroid gland function and structure, possibly preventing its internalization by the tissue by forming chelates and exerting anti-inflammatory effects.

The effect of humic acid substances on the thyroid function and structure in lead poisoning

Lead (Pb) is a heavy metal, which adversely affects thyroid gland function and structure. Due to its high molecular weight and abundant functional groups, humic acid substances (HAS) can form chelates with heavy metals. The experiment was conducted to evaluate the prophylactic effect of HAS on thyroid hormone levels and histopathological lesions of laying hens exposed to lead (Pb) poisoning. After a week of adaptation, 192 Lohmann White laying hens (25 weeks of age) were fed one of four diets: a basal diet (BD) or the BD with HAS (0.15%), with Pb (0.3 g/kg), or with both. Experimental groups were replicated in 12 cages, with four hens each. Pb poisoning did not alter triiodothyronine (FT3; 3.22 ± 0.20 ng/dL) or thyroxine (FT4; 0.71 ± 0.08 ng/dL) concentrations, but caused a 167% increase in thyroid stimulating hormone (TSH) concentration. HAS supplementation returned the high TSH levels of hens exposed to Pb poisoning to normal values. Degenerative changes in the epithelial cells of the thyroid gland of the hens exposed to Pb poisoning were evidenced. Connective tissue cells in the interfollicular area and total amount of colloids with partially atrophic follicles were observed. These histopathological findings were less severe when HAS was added to the diet. In conclusion, HAS alleviates the effects of Pb poisoning on thyroid gland function and structure, possibly preventing its internalization by the tissue by forming chelates and exerting anti-inflammatory effects.(AU)

Beef heifers grazing behavior and herbage intake in natural grassland under rotational grazing / Comportamento ingestivo e consumo de forragem de novilhas de corte em pastagem natural manejada com pastoreio rotativo

It was evaluated the effect of two rest intervals between grazing occupations in rotational grazing; 375 and 750 DD (degree-days); based on the cumulative thermal sum necessary for leaf expansion of native grasses of two functional groups over the grazing behavior variables from beef heifers with 12 months old. The experiment was conducted as a completely randomized block design, with two treatments, three replications and measures repeated over time. Grazing behavior was assessed in three occasions (Nov 2011, Jan and Mar 2012), with 24h each. The herbage intake was estimated using an external marker (Cr2O3). The leaf mass was similar among the rest intervals, with a mean of 1261kg DM ha-1. The average grazing time was 627.4min day-1 and bite rate was 37.1 bites min-1. The average number of daily meals was 5.9 with an average of 118.5 minutes. Number of feeding stations visited per minute was 6.1 and the feeding stations permanence time was of 12 seconds. There was a reduction only on grazing time and bite rate over the periods. The range of thermal sums evaluated to define the rest intervals in rotational grazing proved no effect on heifers' grazing behavior and herbage intake.(AU)

Foram testados os efeitos de dois intervalos de descanso entre pastoreios, 375 e 750 graus-dia, baseado na soma térmica para a expansão foliar de gramíneas nativas de dois grupos funcionais sobre o comportamento ingestivo de novilhas de corte. O delineamento foi em blocos ao acaso, com dois tratamentos, três repetições de área e medidas repetidas no tempo. Foram realizadas três avaliações (nov/11, jan e mar/12), com 24h cada, utilizando novilhas de corte com 12 meses. Estimou-se o consumo de forragem com marcador externo (Cr2O3). A massa de lâminas foliares foi semelhante entre os tratamentos, apresentando média de 1261kg MS ha-1. O tempo médio dispendido pelos animais em pastejo foi de 627,4 minutos e a taxa de bocados média foi de 37,1 bocados minuto-1. O número médio de refeições foi de 5,9 refeições dia-1, com uma média de 118,5 minutos por refeição. Os animais visitaram, em média, 6,1 estações alimentares por minuto e permaneceram nessas estações por 12 segundos. Houve diferença no tempo de pastejo e taxa de bocado nos períodos, com uma redução ao longo do tempo. Os intervalos de descanso testados provaram ter pouco efeito no comportamento ingestivo e no consumo de forragem das novilhas.(AU)

Influência da farinha de bagaço de uva e resveratrol na atividade de enzimas antioxidantes da tilápia-do-Nilo (Oreochromis niloticus) submetida a estresse por calor/oxigênio dissolvido e estresse por classificação de tamanho

O objetivo do presente estudo foi avaliar os efeitos da inclusão dietética da farinha de bagaço de uva sobre o desempenho produtivo, perfil hematológico e atividade das enzimas antioxidantes da tilápia-do-Nilo submetidas a desafio por estresse térmico e hipóxia, e desafio por classificação de tamanho. Um grupo de 600 tilápias invertidas sexualmente (47.56 g ± 0.96) foi distribuído aleatoriamente em 40 aquários de 250 L (15 peixes/aquário) e alimentados com sete dietas práticas contendo níveis de farinha de bagaço de uva 0,0; 0,2; 0,4; 0,6; 0,8; 1,0; 1,5% e uma dieta contendo 0,02% de resveratrol, por 75 dias. As dietas foram formuladas para conter 29% de proteína digestível e 18 MJ de energia digestível kg-1. Após 30 dias de alimentação foram avaliados parâmetros hematológicos e atividade das enzimas do sistema antioxidante. Dois diferentes grupos de peixes foram submetidos a dois tipos de estresse, um grupo foi submetido ao desafio térmico e hipóxia (34°C/0,87 mg/L-1 de oxigênio dissolvido) por dois dias e, outro grupo a desafio por classificação de tamanho. Os mesmos parâmetros hematológicos e atividade das enzimas do sistema antioxidante foram determinados após os desafios. No presente estudo, o perfil hematológico da tilápia-do-Nilo se manteve dentro da faixa de normalidade preconizada para a espécie quando submetidos ao desafio térmico e hipóxia, enquanto no desafio por classificação os peixes apresentaram maiores porcentagens de hematócrito, hemoglobina e menores níveis de concentração de hemoglobina corpuscular média, demonstrando que tal estresse é mais prejudicial aos peixes. A farinha de bagaço de uva e o resveratrol foram capazes de eliminar substâncias geradas pelo estresse oxidativo, não necessitando da ação da enzima catalase frente a ambos os desafios, porém não houve efeito significativo no desempenho produtivo. Os resultados do presente estudo sugerem o nível de suplementação de 1,5% de farinha de bagaço de uva, devido a seu potencial antioxidante determinar resultados numericamente análogos ao resveratrol.

The aim of the present study was to evaluate the effects of grape pomace flour (GPF) on productive performance, hematological profile and antioxidant enzymes activity of Nile tilapia subjected to heat/dissolved oxygen-induced-stress (HDOIS), and size-sorting-induced stress (SSIS). A group of 600 male Nile tilapia (47.56 g ± 0.96) was randomly distributed in 40 250-L aquaria (15 fish / tank) and fed eight practical diets with graded levels of GPF at 0.0; 0.2; 0.4; 0.6; 0.8; 1.0; 1.5% and 0.02% resveratrol for 75 days. The diets were formulated to contain 32% crude protein and 18 MJ kg-1 crude energy. After 30 days of feeding, five fish per treatment were sampled for hematological profile and antioxidant enzyme activity determination. Then, two different groups of fish were subjected to different types of stress, one group was subjected to HDOIS (34 ° C / 0.87 mg / L-1 dissolved oxygen) for two days and another group were subjected to SSIS. After both stressors, the same hematological profile and antioxidant enzyme activity were determined. Our results showed that the hematological profile of Nile tilapia remained within the normal range for the species when subjected to HDOIS, whereas in SSIS, fish showed higher levels of hematocrit, hemoglobin and lower levels of mean corpuscular hemoglobin concentration, demonstrating that such stress can be considered more harmful to fish. GPF and resveratrol were able to eliminate oxidative stress substances, not requiring the action of catalase for both challenges, but there was no significant effect on growth performance. The results of the present study suggest a dietary 37 supplementation level of 1.5% of grape pomace flour, due to its antioxidant potential on determining results numerically analogous to resveratrol.

AVALIAÇÃO DA FOLHA DE MORINGA (Moringa oleifera) NA ALIMENTAÇÃO E IMUNIDADE DE CODORNAS EUROPEIAS (Coturnix coturnix)

A Moringa oleifera é uma planta que tem apresentado importantes características nutricionais e funcionais na alimentação animal. Este estudo objetivou avaliar o efeito da inclusão da folha de Moringa oleifera na alimentação de codornas europeias (Coturnix coturnix) sobre parâmetros de desempenho zootécnico, rendimento de carcaça, peso de órgãos e bioquímica sérica, visando melhorar condições imunológicas, amenizando fatores como estresse causado por calor ambiental, além de reduzir custos com a alimentação sem comprometer o bem-estar. Foram utilizadas 360 codornas europeias mistas da Granja Fujikura®, com 1 a 42 dias de idade, distribuídas aleatoriamente em 05 grupos, que consistiam em 05 tratamentos (06 subgrupos), com n=12. As aves foram alimentadas ad libitum com rações experimentais contendo 05 níveis (0; 1; 2; 3 e 4%) de inclusão de proteína de folhas de Moringa oleifera em substituição a proteína do milho e do farelo de soja (FMO). O desempenho foi avaliado em duas fases (1 a 21 dias e 22 a 42 dias de idade). Aos 28, 35 e 42 dias de idade, amostras de 02 aves por subgrupo experimental foram abatidas para avaliação das carcaças. A coleta de sangue e órgãos ocorreu aos 14, 28 e 42 dias de idade das aves, a partir de 01 ave por subgrupo, sacrificadas para avaliação da bioquímica sérica (Aspartato aminotransferase (AST); Alanina aminotransferase (ALT); Fosfatase alcalina (FAL); Colesterol; Triglicerídeos; Glicose) e peso de órgãos imunes e comestíveis. Os resultados de desempenho, rendimento de carcaça, peso de órgãos e parâmetros sanguíneos foram submetidos à ANOVA e regressão polinomial ou esquema fatorial. Quando houve interação dos fatores analisados, foi realizado teste de Tukey à 5% de significância. Nas condições experimentais, os resultados demonstraram que FMO até o nível 2,24% no período de 1 a 42 dias de idade de codornas europeias, ou até 2,61% no período de 22 a 42 dias de idade, não interferiu no desempenho produtivo. Até o nível 4% de FMO não houve influência no rendimento de carcaça de fêmeas abatidas aos 28, 35 e 42 dias de idade. No entanto, o aumento da inclusão de FMO até 4% reduziu o rendimento de carcaça de machos abatidos aos 35 dias idade que, independentemente do nível FMO não ganham peso após esta idade. A inclusão até 4% de FMO diminuiu o peso da bolsa cloacal de codornas europeias aos 14 dias de idade, provocou aumento do peso do timo e redução do baço aos 42 dias. Não houve interferência nos níveis de glicose e triglicerídeos aos 14, 28 e 42 dias de idade. A inclusão de FMO reduziu o colesterol aos 14 dias, sugerindo que nesse período ocorreu má absorção e digestão de nutrientes. Os níveis de AST, ALT e FAL estiveram dentro da normalidade para aves em todos os níveis de inclusão de FMO, entretanto até 3,03% de FMO provocou aumento de ALT enquanto até o nível 2,26% ocorreu redução da FAL. Os níveis de FMO até 4% demonstraram ser viáveis economicamente, considerando apenas o custo com alimentação de codornas europeias mistas aos 28, 35 e 42 dias de idade, porém observou-se tendência de redução da viabilidade com o aumento da idade. A inclusão de 3% de FMO demonstrou melhor viabilidade econômica, ficando o uso condicionado a disponibilidade e custo na região.

Moringa oleifera is a plant that has shown important nutritional and functional characteristics in animal feed. This study aimed to evaluate the effect of including Moringa oleifera leaf in the feeding of European quails (Coturnix coturnix) on parameters of zootechnical performance, carcass yield, weight of organs and serum biochemistry, aiming to improve immunological conditions, mitigating factors such as stress caused by environmental heat, in addition to reducing food costs without compromising welfare. A total of 360 mixed European quails from Granja Fujikura® were used, aged 1 to 42 days, randomly distributed into 05 groups, which consisted of 05 treatments (06 subgroups), with n = 12. The birds were fed ad libitum with experimental diets containing 05 levels (0, 1, 2, 3 and 4%) of protein inclusion of Moringa oleifera leaves in replacement of corn protein and soybean meal (FMO). The zootechnical performance was evaluated in two phases (1 to 21 days and 22 to 42 days of age). For carcass evaluation, samples of 02 birds per experimental subgroup were slaughtered at 28, 35 and 42 days of age. The sampling of blood and organs occurred at 14, 28 and 42 days of age, from 01 bird per subgroup, sacrificed for evaluation of serum biochemistry (Aspartate aminotransferase (AST); Alanine aminotransferase (ALT); Alkaline phosphatase (ALP); Cholesterol; Triglycerides; Glucose) and weight of immune and edible organs. The results of performance, carcass yield, organ weight and blood parameters were submitted to ANOVA and polynomial regression or factorial scheme. When there was an interaction of the analyzed factors, Tukey's test was performed at 5% significance level. In the experimental conditions, the results showed that FMO up to the level of 2.24% in the period from 1 to 42 days of age of European quails, or up to 2.61% in the period of 22 to 42 days of age, did not interfere in the productive performance. Up to the 4% level of FMO, there was no influence on the carcass yield of females slaughtered at 28, 35 and 42 days of age. However, increasing the FMO inclusion to 4% reduced the carcass yield of males slaughtered at 35 days of age who, regardless of the FMO level, do not gain weight after this age. The inclusion of 4% of FMO decreased the weight of the European quail cloacal pouch at 14 days of age, causing an increase in the weight of the thymus and a reduction in the spleen at 42 days. There was no interference in glucose and triglyceride levels at 14, 28 and 42 days of age. The inclusion of FMO reduced cholesterol at 14 days, suggesting that during this period there was poor digestion and absorption of nutrients. The levels of AST, ALT and ALP were within the normal range for birds at all levels of inclusion of FMO, however up to 3.03% of FMO caused an increase in ALT while up to the 2.26% level there was a reduction in ALP. FMO levels up to 4% proved to be economically viable, considering only the cost of feeding mixed European quails at 28, 35 and 42 days of age, but there was a tendency to reduce economic viability with increasing age. The inclusion of 3% of FMO demonstrated better economic viability, the use being conditioned to availability and cost in the region.

Assessing the performance of macroinvertebrate metrics in the Challhuaco-Ñireco System (Northern Patagonia, Argentina) / Evaluación del rendimiento de distintas métricas utilizando los macroinvertebrados en el sistema lótico de Challhuaco-Ñireco (Patagonia, Argentina)

Siete sitios fueron examinados en el sistema lótico Challhuaco-Ñireco, ubicado dentro del Parque Nacional Nahuel Huapi (PNNH), sin embargo parte de esta cuenca está urbanizada ya que atraviesa la ciudad de San Carlos de Bariloche (150,000 habitantes). Se midieron variables físico-químicas y se colectaron los macroinvertebrados bentónicos durante tres años consecutivos en siete sitios desde la cabecera hasta la desembocadura. Plecoptera, Ephemeroptera, Trichoptera y Diptera predominaron en los sitios cercanos a la cabecera, mientras que Diptera, Oligochaeta y Mollusca dominaron los sitios más bajos cercanos a la desembocadura. En relación con los grupos funcionales, los colectores-recolectores fueron los dominantes en todos los sitios y este patrón fue consistente durante los tres años de muestreo. El análisis de ordenamiento (RDA) reveló que las distribuciones de los ensambles de especies respondieron al gradiente climático y topográfico (temperatura y elevación), pero también fueron asociados con variables relacionadas al impacto antrópico (conductividad, contenido de nitratos y fosfatos). Los ensambles en cabecera estuvieron representados por insectos sensibles, mientras que los taxones tolerantes como Tubificidae, Lumbriculidae, Chironomidae y el crustáceo Aegla sp. fueron dominantes en los sitios urbanizados. En relación con las métricas analizadas, la Riqueza total, el EPT taxa, la diversidad de Shannon y el índice biótico BMPS evidenciaron diferentes niveles de disturbio en el sistema, demostrando que estas medidas son una excelente herramienta para determinar el estado de los ríos de montaña de la Patagonia.(AU)

Seven sites were examined in the Challhuaco-Ñireco system, located in the reserve of the Nahuel Huapi National Park, however part of the catchment is urbanized, being San Carlos de Bariloche (150,000 inhabitants) placed in the lower part of the basin. Physico-chemical variables were measured and benthic macroinvertebrates were collected during three consecutive years at seven sites from the headwater to the river outlet. Sites near the source of the river were characterised by Plecoptera, Ephemeroptera, Trichoptera and Diptera, whereas sites close to the river mouth were dominated by Diptera, Oligochaeta and Mollusca. Regarding functional feeding groups, collector-gatherers were dominant at all sites and this pattern was consistent among years. Ordination Analysis (RDA) revealed that species assemblages distribution responded to the climatic and topographic gradient (temperature and elevation), but also were associated with variables related to human impact (conductivity, nitrate and phosphate contents). Species assemblages at headwaters were mostly represented by sensitive insects, whereas tolerant taxa such as Tubificidae, Lumbriculidae, Chironomidae and crustacean Aegla sp. were dominant at urbanised sites. Regarding macroinvertebrate metrics employed, total richness, EPT taxa, Shannon diversity index and Biotic Monitoring Patagonian Stream index resulted fairly consistent and evidenced different levels of disturbances at the stream, meaning that this measures are suitable for evaluation of the status of Patagonian mountain streams.(AU)