Resumo Introdução A compra institucional para a alimentação escolar é uma oportunidade de incentivo a novas cadeias de abastecimento, sobretudo em nível local. Objetivo Avaliar a gestão municipal do Programa Nacional de Alimentação Escolar (PNAE) relacionada ao fomento e aquisição de alimentos da agricultura familiar. Método Foi realizado levantamento bibliográfico de estudos avaliativos no âmbito do PNAE para seleção dos indicadores e medidas pertinentes ao objeto e desenvolvido um modelo avaliativo. O modelo avaliativo foi pactuado após submissão a oficinas de consenso. Foi elaborado um questionário e enviado por meio eletrônico a 18 municípios de Santa Catarina. A amostra foi definida de forma intencional, e os municípios selecionados por meio de sorteio. Para avaliar as ações da gestão municipal do PNAE destinadas ao fomento e aquisição de alimentos da agricultura familiar, foram utilizados 5 indicadores, 9 medidas e suas respectivas questões. Resultados A avaliação dos municípios foi predominantemente “regular” (88%; n=14). Conclusão A avaliação apontou fragilidades da gestão municipal em relação ao desconhecimento da legislação e não aplicabilidade dos critérios previstos em normativa, especialmente quanto ao Planejamento de Cardápios, realização de Chamada Pública e seleção dos Projetos de Venda.

Abstract Background The institutional purchase for school feeding is an opportunity to encourage new supply chains, especially at the local level. Objective To evaluate the municipal management of the National School Feeding Program (PNAE) related to the promotion and acquisition of food from family agriculture. Method A bibliographic survey of evaluative studies was carried out within the scope of the PNAE to select indicators and measures pertinent to the object and develop an evaluation model. The evaluative model was agreed after submission to consensus workshops. A questionnaire was developed and sent electronically to 18 municipalities of Santa Catarina. The sample was intentionally defined and the municipalities selected by lot. In order to evaluate the actions of municipal management of the PNAE for the promotion and acquisition of food from family agriculture, five indicators, 9 measures and their respective issues were used. Results The evaluation of municipalities was predominantly “regular” (88%, n = 14). Conclusion The evaluation pointed to fragilities of municipal management in relation to the lack of knowledge of the legislation and non-applicability of the criteria set forth in regulations, especially regarding menu planning, public call and selection of sales projects.

ABSTRACT. This study aimed to evaluate the effect of cultivating a combination of common vetch (Vicia sativa L.) with black oats (Avena strigosa Schreb.) on the chemical composition of forage and the grazing behavior of heifers. To accomplish this, two paddocks 2500m2 each from a Voisin Rational Grazing management system were divided into three blocks each and then into thirds (278m²) characterizing a randomized block design. Three different forage compositions were distributed into these thirds: oats grown alone, vetch grown alone, and oats grown with vetch. Forage samples were collected after 65 days through the square method. Right after collection, three groups of four heifers each grazed the plots for two hours in a 3x3 double Latin Square design for behavioral observation, grazing simulation through the hand-plucking method, and biting rate determination. Forage samples collected either by hand-plucking or the square method, were analyzed for chemical composition and “in vitro” degradability. Statistical analyses were performed using the R package lme4. Data were evaluated with linear mixed-effects models. The inclusion of common vetch significantly increased forage production and oat protein content, but decreased the fiber content, which promoted better “in vitro” degradability. Grazing frequency was higher in pasture where oats were grown with vetch, but the biting rate was similar in all the three forage compositions evaluated. Forage collected by the square method did not differ from forage consumed by the heifers, probably meaning low herbage selectivity by heifers. Furthermore, no interaction of investigated variables occurred between forage compositions and the method of collection. The inclusion of common vetch with black oats increased forage chemical composition, “in vitro” degradability, and forage production, thus having positive effects on the time cows spent grazing.

Resumen Antecedentes: La demanda por alimentos naturalmente enriquecidos se ha venido incrementado en todo el mundo. A través de la nutrición animal es posible incorporar moléculas nutracéuticas en la leche. El uso de estas moléculas pretende mejorar la salud humana. Objetivo: Evaluar los efectos de la peletización y la monensina sobre la ingesta, digestibilidad de la materia seca (DM) y nutrientes, producción de leche, composición y perfil de ácidos grasos (FA) en leche de vacas en pastoreo que consumen alimento concentrado formulado con linaza molida (GF). Métodos: Cuatro vacas Holstein fueron distribuidas en los siguientes tratamientos: 1) ración conteniendo GF; 2) GF + 32,93 mg/Kg de monensina (GFM); 3) GF en pellets (GFP); 4) GF en pellets + 32,93 mg/Kg de monensina (FMP). Resultados: Los tratamientos no mostraron efectos en el consumo y digestibilidad de la DM y nutrientes, excepto por el consumo de extracto etéreo, con una reducción del 28% en las raciones peletizadas. La monensina incrementó la concentración de ácido linoleico conjugado (CLA) en 47%. La peletización aumentó el contenido de CLA (70%), FA poliinsaturados (PUFA; 25%) y FA monoinsaturados (16%); y redujo las concentraciones de C18 en 19%, y FA saturados total en 14%. Conclusión: El peletizado y la monensina no alteran la ingesta de alimento ni la digestibilidad de la DM y nutrientes. El proceso de peletizado aplicado a concentrados que contienen linaza mejora la calidad de los ácidos grasos de la leche.

Abstract Background: Demand for naturally enriched foods is increasing worldwide. Animal nutrition allows incorporating nutraceutical molecules into milk. These molecules are intended for improving human health. Objective: To evaluate the effects of pelleting and monensin addition to the diet on intake, digestibility of dry matter (DM) and nutrients, milk yield and composition, and fatty acids (FA) profile in cows kept on pasture and supplemented with concentrate containing ground flaxseed (GF). Methods: Four Holstein cows were assigned to the following treatments: 1) concentrate with GF; 2) GF + 32.93 mg/Kg monensin (GFM); 3) GF pelleted (GFP); 4) GF pelleted + 32.93 mg/Kg monensin (FMP). Results: Treatments did not show effects on digestibility of dry matter (DM) and nutrients or feed intake, with the exception of ether extract intake, which was reduced by 28% with pelleting. Addition of monensin increased the conjugated linoleic acid (CLA) concentration by 47%. Pelleting increased the concentrations of CLA (70%), polyunsaturated FA (PUFA; 25%), and monounsaturated FA (MUFA; 16%), and reduced the concentrations of steric acid (C18) in 19% and total saturated FA (SFA; 14%). Conclusion: Pelleting and monensin does not alter feed intake and digestibility of DM and nutrients. Pelleting of concentrate feed containing flaxseed improves milk FA quality.

Resumo Antecedentes: A procura por alimentos naturalmente enriquecidos tem aumentado por parte dos consumidores. Através da nutrição animal é possível incorporar ao leite moléculas nutracêuticas, essas moléculas são conhecidas por melhorarem a saúde humana. Objetivo: Avaliar os efeitos da peletização e monensina sobre o consumo, digestibilidade da matéria seca (DM) e nutrientes, produção de leite, composição e perfil de ácidos graxos (FA) no leite de vacas em pastejo e suplementadas com concentrado contendo linhaça moída (GF). Métodos: Quatro vacas Holandesas foram distribuídas nos tratamentos: 1) concentrado contendo GF; 2) GF + 32,93 mg/Kg de monensina (GFM); 3) GF peletizado (GFP); 4) GF peletizado + 32,93 mg/Kg de monensina (FMP). Resultados: Os tratamentos não apresentaram efeitos sobre consumo e digestibilidade da DM e dos nutrientes, exceto para o consumo de extrato etéreo, com redução de 28% com a peletização do concentrado. A adição de monensina aumentou a concentração de ácido linoleico conjugado (CLA) em 47%. A peletização aumentou os teores de CLA (70%), FA poli-insaturados (25%) e FA monoinsaturados (16%); e reduziu as concentrações de C18 em 19% e AG saturados totais em 14%. Conclusão: Peletização e monensina não alteram o consumo e digestibilidade da DM e dos nutrientes. O processo de peletização aplicado em concentrados contendo linhaça melhora a qualidade dos FA do leite.

ABSTRACT The objective of this study was to evaluate milk quality for somatic cell count (SCC) analysis and total bacterial count (TBC) in agroecological production systems and conventional systems, relating them to the frequency of milking practices and types of facilities. The study was conducted in 2013 and 2014, in the western region of Paraná State, Brazil. We used a semi-structured questionnaire to identify management practices of producers in the 17 dairy systems (DS) in the city of Diamante d'Oeste and the 27 DS in Toledo. Milk sampling was performed monthly. Data were analyzed using two statistical methods. These were then used to create cross tabulation of groups with production systems and practices that can influence product quality. Cluster classification analysis allowed grouping of the initial 44 production systems into three homogeneous groups: Group 1, with better quality regarding the normative instruction 62 (NI62), with average values of SCC 407.37 (cells × 1000/mL) and TBC 210.50 (cfu × 1000/mL); Group 2, with SCC 328.50 (cells × 1000/mL) and TBC 699.75 (cfu × 1000/mL), both outside the NI62 parameters; and Group 3, with SCC 680.25 (cells × 1000/mL), considered low- and high-value TBC 1775.25 (cfu × 1000/mL), out of NI62. The results indicate that management practices and some other preventions adopted during milking are the determining factors of milk quality. Therefore, SCC and TBC levels are not determined by agroecological or conventional production systems, but rather, these levels are determined by the practices differentially adopted by the production systems.

Resumo O teste do álcool é amplamente utilizado na recepção dos laticínios para a verificação da estabilidade do leite cru. O leite que não é estável no teste e não apresenta acidez elevada é definido como leite instável não ácido (LINA). A sua ocorrência tem característica multifatorial e pode estar relacionada ao manejo nutricional inadequado. Este estudo objetivou avaliar a influência da infraestrutura da propriedade e da alimentação dos animais sobre a ocorrência de LINA. A infraestrutura foi caracterizada através de questionário guia semiestruturado. Analisou-se a composição centesimal do leite das propriedades, resistência ao teste do álcool, acidez titulável e o pH. Foram consideradas LINA as amostras que precipitaram em concentração de álcool menor ou igual a 72%, com acidez e pH normais. Nos alimentos coletados, determinou-se o teor de fibra em detergente neutro. Os dados foram avaliados através de análise fatorial e de agrupamento utilizando o pacote estatístico SAS. O uso de suplementos alimentares volumosos e concentrados, com consequente melhoria da produtividade animal e maior teor de lactose no leite foi relacionado com menor ocorrência de LINA nas condições estudadas. A ocorrência de LINA apresentou pouca relação com a infraestrutura das propriedades e com a estação do ano.

Abstract The alcohol test is largely used in the dairy reception platform in order to verify raw milk stability. Milk that is not stable in the test and does not present high acidity is defined as unstable non-acid milk (UNAM). Its occurrence has a multifactorial characteristic and may be related to inadequate nutritional management. This study aimed to evaluate the influence of farm structure and animal feed on the occurrence of UNAM. The farm structure was characterized by means of a semi-structured questionnaire guide. Milk composition of the farms, resistance to alcohol test, titratable acidity and pH were analyzed. UNAM samples were those that precipitated at alcohol concentration less than or equal to 72%, with normal acidity and pH. Neutral detergent fiber was determined in the feed collected. Data were evaluated using factor and cluster analysis by using SAS statistical package. The use of roughages and concentrated food supplements with consequent improvement of animal productivity and higher lactose content in milk were associated with lower occurrence of UNAM under the studied conditions. The occurrence of UNAM had little relation with the farm structure and with the season of the year.

Spectroscopy associated with chemometrics is a non-destructive method of the samples for the prediction of phenolic compounds. The objective of the work was to apply the near infrared spectroscopy (NIR) technique for the prediction of phenolic compounds and flavonoids in aerial part samples of cover crops plants Raphanus sativus L., Secale cereale L. and Avena strigosa L. Samples were collected at 60, 80 and 100 days after sowing (DAS) of the plants and, after lodging (DAA), at 15 and 30 days, in an experiment implanted in the field, in the city of Ituporanga, Santa Catarina. The samples were homogenized, identified, transported on dry ice, lyophilized, crushed, sieved and stored at -20 °C for analysis. For the calibration, 84 samples were used and for the validation 10 samples. The combination of NIR spectroscopy and multivariate analysis by partial least squares regression allowed the development of prediction models of phenolics and flavonoids with associated errors averaging 10%. NIR spectroscopy is recommended for the development of calibration models because it allows to non-destructive infer phenolic and total flavonoid contents, with high analytical frequency, without the use of reagents and other inputs required by the reference method, with results very close to those obtained in the laboratory.

ABSTRACT This study aimed to evaluate the effects of soybean hulls (SBH) as a ground corn replacement (0, 50, and 100% SBH) on the parameters of the lactation curve and on lactation curves and milk composition. Fourteen multiparous Saanen goats were used during their lactation period, from kidding until the drying of their milk on the 228th day of lactation, and were distributed in a completely randomised design. The data was analysed using Bayesian methodology to minimise the effect of the low number of animals and to allow for comparison of the curve parameters estimated by Wood's nonlinear model. The SBH had no effect on the initial milk yield; nevertheless, the SBH reduced the rate of yield until lactation peak and accelerated the declining rate of yield after lactation. The treatments did not affect dry matter intake. The inclusion of SBH increased the fat content in the milk, which was also influenced by the lactation stage of the goats. Effects were observed on polyunsaturated fatty acids (PUFA), PUFA/total AG ratio, and the n-6:n-3 ratio of goat milk fat. The lactation stage changed the content of saturated fatty acid, monounsaturated fatty acid, and C18:2 (conjugated linoleic acid). The SBH can therefore be used as a ground corn replacement in the diets of lactating goats, as changes in the lactation curve parameters did not result in changes in total yields. Nevertheless, if the milk fat increases, then as quality rises, so could payment by quality, and thus an increase in profit margins per liter of milk sold.

Four lactating Holstein cows were assigned to a 4 × 4 Latin square design to determine the effects of feeding sticky coffee hull (SCH) as a source of antioxidants on dairy cows fed with high PUFA diets. The treatments (on DM basis) were control diet, diet with 30 g/kg of soybean oil, diet with 30 g/kg of soybean oil and 100 g/kg of SCH, and diet with 30 g/kg of soybean oil and 150 g/kg of SCH. Inclusion of 150 g/kg of SCH decreased the crude protein digestibility. Lower values of NDF digestibility were also observed when cows were fed with 100 g/kg and 150g/kg of SCH. The digestibility of NDT was lower in the control and 150 g/kg of SCH diets. Milk production and composition did not differ among the treatments. Inclusion of SCH increased the total polyphenols and flavonoids in the milk and reducing power as well. Soybean oil and SCH supplementation increased the LDL and total cholesterol concentration in the plasma. Milk fatty acid profile was barely altered by the treatments. In conclusion, the results confirmed that SCH added up to 15% in the diet did not alter milk production, improved its stability, and incorporated antioxidants substances in the milk, improving its quality for human health.

The objective of this study was to evaluate the milk production, composition, milk fatty acid profile, butter texture and blood parameters of Holstein cows fed corn silage and concentrate containing one of the following: ground sunflower seeds; ground sunflower seeds treated with 50 g of lignosulfonate/kg of sunflower dry matter; pelleted sunflower seeds; or ground sunflower seeds pelleted and treated with 50 g of lignosulfonate/kg of sunflower dry matter. Four lactating cows were used, each with 130±28 days in lactation and a body weight of 569±63 kg. These animals were distributed in a Latin square design with four periods of 21 days each, with 14 days of adaptation and seven days of data collection. The diets were formulated to meet nutritional requirements and had a forage:concentrate ratio of 60:40. The milk fat was lower in the pelleted treatments. The concentrations of 16:1 n-11 and trans18:1 n-9 in the milk increased, and the n-6:n-3 ratio was higher for the pelleted treatments. The firmness and adhesiveness of the butter and the blood parameters analyzed were not affected by the treatments. Addition of lignosulfonate is not effective in protecting polyunsaturated fatty acids from the ruminal biohydrogenation process, and the pelleting process has little effect on the milk fatty acid profile and can not change the butter texture.

The objective of this study was to evaluate intake, in vitro and apparent digestibility and ruminal parameters of Holstein cows that were confined and fed corn silage and concentrate containing: ground sunflower seeds (GS); ground sunflower seeds treated with 5% lignosulfonate (GSL); pelleted sunflower seeds (PS); or ground and pelleted sunflower seeds treated with lignosulfonate (PSL). Four lactating cows with 130±28 days of lactation and body weights of 569±63 kg were used. These animals were distributed in a Latin square design with four diets and four periods of 21 days each. There were no differences in the intakes (% body weight) of dry matter (DM), organic matter (OM), mineral matter (MM), crude protein (CP), neutral detergent fiber (NDF) or acid detergent fiber (ADF). The apparent digestibility of DM, OM, CP, EE, NDF, ADF and NFC were similar for all the diets, with a tendency towards decreased CP digestibility for all the pelleted diets (65.79%) compared with the non-pelleted diets (69.66%). A negative effect of lignosulfonate was observed for the in vitro digestibility (IVD) of DM, and a negative tendency was observed for the IVD of OM. Pelleting decreased the concentration of acetic acid (55.95 × 58.82 mM) in rumen fluid. There was no effect of diet on pH (6.17) or ammonia nitrogen concentration (18.19 mg/dL). Pelleting and lignosulfonate do not promote the protective effect of sunflower seed nutrients as expected, and it may be more feasible to provide ground sunflower seed.

Four multiparous Holstein cows averaging 548 kg of body weight and 74 d in lactation were used in a Latin square design with four 21-d experimental periods to determine effects of feeding extruded versus non-extruded canola seed, with or without 50 g/kg lignosulfonate on rumen fermentation, nutrient flow to the omasum, and degradability of dry matter (DM) and N of each diet. The DM effective degradability increased with extrusion and lignosulfonate treatment had no effect. The effective degradability of N was similar between diets. Lignosulfonate treatment of extruded versus non-extruded canola seeds decreased ruminal and total tract apparent digestibility of organic matter. The lowest apparent ruminal and highest intestinal digestibilities of protein, expressed as a percentage of N intake were observed for cows fed extruded canola seeds without lignosulfonate. Lignosulfonate treatment and extrusion had no effect on pH and concentrations of ammonia N and volatile fatty acids in the rumen. Results suggest that extruded canola seed untreated with formaldehyde may stimulate efficiency of microbial protein synthesis and is an effective means of increasing the availability of protein in the small intestine without affecting the total tract apparent digestibility of protein.

The objective of this study was to evaluate productive performance and milk quality of Saanen goats fed diets with soybean hulls replacing ground corn (0, 50 and 100% replacement) in early lactation (from birth to 50 days of lactation). Fourteen goats (72.30±9.14 kg of BW) were used in a completely randomized design. Animals were confined in individual stalls, with daily control of feed intake and milk production. On the 30th day of lactation, fecal sampling started in order to determine nutrients digestibility. Every month, milk samples were collected for analyses of fat, protein, lactose and total solid percentage, somatic cell count, N-urea, acidity, density and also milk fatty acid profile. No differences were observed between diets for body weight, daily weight gain and intake (kg/day) of dry matter, organic matter, crude protein or indigestible neutral detergent fiber. However, for neutral detergent fiber intake, the diet with complete substitution presented the best results. Cocerning digestibility coefficients of dry matter and nutrients (organic matter, crude protein and neutral detergent fiber) the diet with 100% replacement also presented the best results. For milk production, milk production efficiency and milk composition, no difference was observed between diets. For milk fatty acid profile, there were differences between diets for some fatty acids. Soybean hulls can be used replacing ground corn in diets for Saanen goats in the early lactation, because it improves the digestibility of the diet and nutrients, does not change productive performance or the milk physical-chemical quality and increases the content of n-3 fatty acids in milk.

Oito vacas da raça Holandesa com 570 ± 43 kg de peso vivo e 60 ± 20 dias de lactação foram distribuídas em delineamento quadrado latino duplo, com quatro períodos de 21 dias, para avaliar o fornecimento de linhaça inteira ou moída, com ou sem suplementação de monensina sódica (0,02% na MS), sobre o perfil de ácidos graxos da manteiga armazenada por 15 e 45 dias. O fornecimento de linhaça moída, em comparação ao de linhaça inteira, diminuiu as porcentagens relativas de 16:0, cis7-16:1, 17:0, e cis10-17:1, mas aumentou cis9,trans11-18:2, cis3-18:3, e ômega-3 na manteiga, reduzindo a porcentagem relativa de ácidos graxos de cadeia média e aumentando o conteúdo de ácidos graxos poliinsaturados. A suplementação com monensina aumentou as porcentagens relativas de cis9,trans11-18:2 e tendeu a aumentar a porcentagem relativa de 17:0 e diminuir ácidos graxos saturados na manteiga. A manteiga das vacas que receberam monensina na dieta apresentou menor porcentagem relativa de cis6-20:4. As porcentagens relativas de cis9-16:1, cis10-17:1, 18:0, trans11-42 18:1, cis9-18:1, cis3-18:3, cis6-20:4 na manteiga armazenada por 15 dias foram maiores que naquela armazenada por 45 dias e as porcentagens relativas de cis3-20:5 tenderam a diminuir com o aumento do período de armazenamento. Em consequência, as porcentagens relativas de ácidos graxos saturados e de cadeia média aumentaram com o tempo de armazenamento, enquanto ácidos graxos monoinsaturados e de cadeia longa diminuíram. A manteiga enriquecida com ácidos graxos poliinsaturados pode ter vida de prateleira mais curta, devido ao efeito negativo do armazenamento no perfil de ácidos graxos, que pode provocar oxidação e rancidez.

Eight Holstein cows with body weight 570 ± 43 kg and 60 ± 20 lactation days were distributed in a double Latin square design with four 21-day periods to determine the effects of feeding ground or whole flaxseed with or without monensin supplementation (0.02% on a dry matter basis) on fatty acid profile of butter stored for 15 and 45 days. Ground flaxseed supply, in comparison to whole flaxseed, reduced relative percentages of 16:0, cis7-16:1, 17:0, and cis10-17:1 but it increased those of cis9,trans11-18:2, cis3-18:3, and omega 3 fatty acids in butter fat, reducing relative percentage of medium-chain fatty acids and increasing the content of polyunsaturated fatty acids. Supplementation with monensin increased relative percentages of cis9,trans11-18:2 and tended to increase relative percentage of 17:0 and decrease that of saturated fatty acids in butter. Butter from cows fed diet with monensin presented lower relative percentages of cis 6-20:4. Relative percentages of cis 9-16:1, cis10-17:1, 18:0, trans11-18:1, cis9-18:1, cis3-18:3, cis6-20:4 in butter stored for 15 days were higher than those stored for 45 days and the relative percentages of cis3-20:5 tended to decrease with the increase of storage period. As a result, relative percentages of saturated fatty acids and medium-chain fatty acids increased with storage time, while those of monounsaturated and long-chain fatty acids decreased. Butter enriched with polyunsaturated fatty acids may have a shorter shelf life due to the negative effect of storage on fatty acid profile which may cause oxidation and rancidity.

Avanços científicos em nutrição de vacas leiteiras têm ocorrido na primeira década do século XXI. Desta forma, este artigo abordará os principais aditivos utilizados na alimentação de vacas leiteiras no período de transição, empregados com o objetivo de diminuir a incidência de distúrbios metabólicos, na qual serão discutidos separadamente com ênfase em seus mecanismos de ação, utilização e eficácia. A partir da versão atualizada do NRC de 2001 serão abordadas algumas modificações na utilização de proteína com intuito de alcançar de forma precisa as exigências em nitrogênio e aminoácidos para vacas leiteiras. Além disso, observa-se que os principais avanços em manipular a gordura do leite estão relacionados com a suplementação lipídica na dieta, então, discutir-se-ão estudos sobre manipulação do perfil de ácidos graxos do leite na qual dependem da ação dos microrganismos ruminais sobre os ácidos graxos poli-insaturados da dieta, e também, os principais fatores relacionados à diminuição da gordura do leite.

Scientific advances in nutrition of dairy cows in the first decade of the XXI century have occurred. This paper will review the most common additives fed to transition cows to decrease the incidence of metabolic disorders, which will be discussed separately with emphasis on their mechanisms of action, utilization and efficiency. Some changes on protein in the 2001 updated version of the Nutrient Requirements of Dairy Cattle to reach better precision of the nitrogen and amino acid requirements of lactating cows also are presented. Many of the advances in nutritional manipulation of milk fat concentration are related to fat supplementation, then the relationship between the action of rumen microbes on biohydrogenation of dietary polyunsaturated fatty acids and milk fatty acid profile are discussed as well as the main factors identified as being responsible for milk fat depression.

Objetivou-se avaliar o efeito da substituição da silagem de milho pela silagem a rama da mandioca na produção e do leite. Foram utilizadas doze vacas em lactação em delineamento experimental inteiramente casualizado em bloco com quatro tratamentos e três repetições por bloco. A silagem de milho (SM) foi substituída pela silagem de rama de mandioca (SRM) em níveis 0, 20, 40 e 60%. A substituição da silagem de milho em diferentes níveis de SRM teve pouco efeito nos parâmetros estudados. A densidade do leite diminuiu com o aumento dos níveis de substituição. Os ácidos graxos 4:0 e 6:0 apresentaram comportamento quadrático, enquanto que os ácidos 8:0, 10:0, e 15:0 apresentaram comportamento linear quando o conteúdo de SRM foi aumentado. A substituição de 20 a 60% de SRM resultou em diminuição significativa dos custos de alimentação em comparação a silagem de milho. Os resultados sugeriram que a SRM foi um bom substituto da SM para vacas leiteiras.

This study aimed to evaluate the effect of corn silage (CS) replacement by cassava's foliage silage (CFS) on the production and quality of milk. Twelve lactating dairy cows were used in a randomized block experimental design with four treatments and three repetitions per block. CS was replaced by CFS at the levels of 0, 20, 40, and 60%. The replacement of CS by different levels of CFS had very low effect on the variables studied. Milk density decreased when the replacement level was increased. Fatty acids 4:0 and 6:0 presented a quadratic behavior, while fat acids 8:0, 10:0, and 15:0 presented a linear behavior as their concentrations fell when CFS diet content was increased. The CS replacement by 20% until 60% CFS resulted a significant decrease in the feeding costs. The results suggested that CFS was a good replacement of CS for dairy cows.