Glicerina cruda en la dieta de bovinos: efecto sobre los parámetros bioquímicos séricos

El objetivo fue evaluar posibles alteraciones en los valores bioquímicos séricos de bovinos de engorde confinados, recibiendo elevadas concentraciones de glicerina cruda en la dieta. Treinta novillos Nelore fueron utilizados para las colectas de sangre, las cuales se realizaron cada 28 días. Los animales fueron confinados durante 103 días, alimentados con cinco dietas experimentales con 0; 7.5; 15; 22.5 y 30% de glicerina cruda en la materia seca, formuladas para obtener una relación entre forraje: concentrado de 30:70, en la que el ensilaje de maíz fue la fuente forrajera, y el concentrado compuesto por grano de maíz, cascarilla de soya, torta de girasol, glicerina cruda, carbonato de calcio, fosfato bicálcico y sal común. Se utilizó un diseño en bloques al azar, con cinco tratamientos y seis repeticiones, utilizando contrastes ortogonales para determinar los efectos lineal, cuadrático y cúbico de la adición de glicerina. Hubo un efecto lineal de la adición de glicerina sobre las concentraciones de creatina quinasa (P=0.02), cuadrático sobre la de alanina amino transferasa (P=0.009), cúbico sobre la de urea y creatinina (P=0.008 e P=0.002, respectivamente). La adición de glicerina, considerando el tratamiento control, afectó significativamente (P<0.05) las concentraciones de amino transferasa, alanina amino transferasa y creatinina dietas para bovinos tipo carne, con elevadas proporciones de glicerina, ocasionan alteraciones en los parámetros bioquímicos séricos de los animales

Marandu palisade grass management strategies at the beginning of the deferment period and effects on tillering

Pasture mowing at the beginning of deferment stimulates tillering and can be used in different ways. The aim of this study was to understand how the mowing of Urochloa brizantha cv. Marandu Syn. Brachiaria brizantha cv. Marandu (marandu palisade grass) prior to the deferment period modifies tillering activity and the characteristics of young, mature, and old tillers. Three mowing strategies were evaluated: canopies kept at a height of 15 cm for five months before deferment (15/15 cm); canopies kept at 30 cm (30/15 cm) or 45 cm (45/15 cm) for five months before deferment and posteriorly cut to 15 cm at the start of the deferment period. The structural characteristics of young, mature, and old tillers of marandu palisade grass were compared only at the end of the deferment period. The tiller appearance rate was greater before (16.0%) than during (6.4%) the deferment period, but a contrasting response pattern was observed for the tiller mortality rate. The defoliation strategies that resulted in greater numbers of tillers in the canopies were 30/15 cm (2,098 tillers m-²) and 45/15 cm (2,160 tillers m-2). The defoliation strategy that generated the greatest percentage of young tillers in the canopy was 45/15 cm (26.1%), while the percentage of old tillers was greater in the canopies submitted to the 15/15 cm (64.1%) and 30/15 cm (61.5%) strategies. Weight and percentage of live stems of mature and old tillers were greater in relation to young tillers. The percentage of live leaves was grater in young tillers (52.6%), intermediate in mature tillers (41.4%), and lower in old tillers (21.3%). Regarding the percentage of dead leaves, the opposite trend was observed, where the percentage was greater in the old than in young tillers. Leaf area was greater in mature tillers (55.3 cm²) than in old tillers (29.2 cm²). Mowing of the marandu palisade grass to 15 cm at the beginning of the deferment period increases the number of young tillers, which have a more favorable morphological composition than mature and old tillers

Feedlot performance, carcass characteristics, and meat characteristics of lambs grown under silvopastoral systems

Crossbred lambs were grown under different production systems (unshaded, moderate shading, intense shading) and were submitted to a feedlot finishing period where the performance, efficiency, carcass characteristics, and meat characteristics were evaluated. The dry matter intake was similar among treatments as well as the daily gain and feed efficiency. Hot and cold carcass weights, their dressing percentages, initial and final carcass temperature and pH, as well as initial and final color of meat were unaffected by treatments. In conclusion, the silvopastoral system used during the growing phase neither improved feedlot performance, feed efficiency, nor carcass and meat characteristics of crossbred lambs.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Conductas de ingestión en bovinos de la raza Nelore recibiendo altas concentraciones de glicerina cruda

The objective of this study was to evaluate the inclusion of up to 30% crude glycerin in Nellore cattle diets and its effects on feeding behavior parameters. It were used 30 animals with 277.7kg BW and 18 months old, which were kept in feedlot in individual pens during 103 days (21 adaptation and 82 data collection). The animals were assigned (initial weight) in blocks and submitted to the following treatments: G0; G7.5; G15; G22.5; and G30, corresponding to control group, 7.5, 15, 22.5, and 30% crude glycerin in the diet dry matter, respectively. The feeding behavior (feeding, idle, ruminating, number of chews, feeding efficiency and ruminating efficiency) were evaluated for three days. Data were analyzed as a completely randomized block design, analyzing contrasts and observing the significance of linear, quadratic and control treatment × glycerin treatments effects. The inclusion up to 30% crude glycerin in diets of Nellore cattle altered the feeding efficiency, expressed in g NDF h-1, the ruminating efficiency relative to NDF, the time and number of chews per ruminal bolus, facilitating the feed ingestion and directly influencing the time spent on feeding.El objetivo de este estudio fue evaluar la inclusión de hasta 30% de glicerina cruda en dietas para bovinos de la raza Nelore y su efecto sobre parámetros del comportamiento ingestivo. Se utilizaron 30 animales con 277.7 kg de PV y 18 meses de edad, los cuales fueron mantenidos en confinamiento en corrales individuales durante 103 días (21 de adaptación y 82 de colecta de datos). Los animales fueron divididos en bloques (peso inicial) y sometidos a los siguientes tratamientos: G0; G7.5; G15; G22.5 y G30, correspondientes al grupo control, 7.5, 15, 22.5 y 30% de glicerina cruda en la materia seca de la dieta, respectivamente. Las conductas del comportamiento (alimentación, ocio, rumia, número de masticaciones merícicas, eficiencias de alimentación y rumia) se evaluaron durante tres días. Los datos fueron analizados según un diseño en bloques al azar, realizando análisis de contrastes y observando la significancia de los efectos lineal y cuadrático y del tratamiento control × tratamientos con glicerina. La inclusión de hasta 30% de glicerina cruda en la dieta de los bovinos de la raza Nelore alteró la eficiencia de alimentación, expresada en g FDN h-1, la eficiencia de rumia en relación al FDN, el tiempo y número de masticaciones merícicas por bolo ruminal, facilitando la ingestión de los alimentos, e influenciando directamente el tiempo de alimentación

In Vitro Degradability and Methane Production from By-Products Fed to Ruminants

The feasibility of unconventional feed for ruminants must be analyzed for appropriate use as sources of energy or protein that contribute to a sustainable production system addressing concerns about climate change, greenhouse gas emissions, and food security. The objective of this study was to evaluate the nutritive value of by-products including bean residue (BR), bean straw (BS), cassava bagasse (CB), corn straw (CS), orange bagasse (OB), peanut shell (PS), sugarcane bagasse (SB), soybean hull (SH), and sugarcane straw (SS). Chemical composition, in vitro degradability, and fermentative parameters were analyzed and subjected to multivariate and principal component analyses. Crude protein content was highly variable among by-products with BR and SH presenting the highest values (p p p p p < 0.001) were higher in CB, BR, BS, and OB. Multivariate cluster analysis showed three distinct groups with the most degradable in group 1 followed by group 2. These results demonstrate that the by-products used in this study did not impair in vitro fermentation, and thus have the potential to be used in the diets of ruminants and to improve the sustainability of the livestock production sector

Urban sewage sludge stabilization by alkalization-composting-vermicomposting process: Crop-livestock residue use.

Waste management practices are vital for human health and the environment in a world where natural resources stress is expected to increase with the growth of population. Our study aimed to evaluate the potential use of crop-livestock residue as a bulking agent associated with the ideal level of hydrated lime for the stabilization and sanitization of urban sewage sludge through the alkalization-composting process. Therefore, we determined the alkalization efficiency on the heavy metal concentration in urban sewage sludge, quantified the viable eggs of helminths in pure and alkalized sludge, and measured the rate of earthworms (Eisenia fetida) surviving in the vermicomposting process using different levels of alkalized urban sewage sludge associated with crop-livestock residue. Four sequential trials were carried out in a completely randomized design with three replicates. The lime alkalization reduced the levels of Ba, As, Pb, Cu, Cr, Mo, Ni, and Zn compared to the pure urban sewage sludge. Using 30% w/w of lime in the urban sewage sludge (SS-30) for composting process reduced the viable helminth eggs by 71, 72, and 69% for sugarcane bagasse (Saccharum officinarum; SB), fresh chopped Napier-grass (Pennisetum purpureum; NG), and bovine ruminal content (BR), respectively. The ideal level of hydrated lime for stabilization and sanitization of urban sewage sludge was found to be 30%, which was able to reduce the heavy metals. The residues have the potential as a bulking agent for the composting of urban sewage sludge when associated with alkalization. The lime alkalization decreases the total number of helminth eggs and the number of viable eggs. The possibility of starting a vermicomposting using the mixtures is promising, evidenced by the earthworm survival in composting urban sewage sludge mixed with crop-livestock residues after 45 days of composting. The earthworm survival is maintained by an association of at least 80% of the crop-livestock residues