Neste trabalho, foram avaliadas as características fermentativas e químico-bromatológicas da silagem de capimelefante (CE) com diferentes níveis de inclusão, durante a ensilagem, do coproduto da extração da polpa do abacaxi, a casca de abacaxi (CA), nas proporções de 0,0; 12,5; 25,0; 37,5 e 50,0%, da matéria natural do capim-elefante. O material foi ensilado em silos laboratoriais e, após 180 dias, os silos foram abertos e coletaram-se amostras para a determinação dos teores de matéria seca (MS); carboidratos solúveis (CHOS); potencial hidrogeniônico (pH); nitrogênio amoniacal em percentagem do nitrogênio total (NNH 3 /NT); extrato etéreo (EE); proteína bruta (PB); proteína insolúvel em detergente neutro em percentagem do nitrogênio total (PIDN/NT); proteína insolúvel em detergente ácido em percentagem do nitrogênio total (PIDA/NT); fibra em detergente neutro (FDN); fibra em detergente ácido (FDA); celulose (CEL); lignina (LIG); nitrogênio insolúvel em detergente neutro (NIDN); nitrogênio insolúvel em detergente ácido (NIDA) e digestibilidade in vitro da matéria seca (DIVMS). Para a avaliação do efeito dos tratamentos, utilizou-se delineamento experimental inteiramente casualizado, com quatro repetições, executando-se o estudo de regressão para cada variável analisada (P < 0,05). De acordo com as equações de regressão, para as características fermentativas, as silagens podem ser consideradas de muito boa qualidade. Quanto às frações fibrosas da silagem, a inclusão de níveis crescentes deste coproduto contribuiu para diminuí-las, o que pode ser confirmado pelos resultados encontrados para a DIVMS. A inclusão da CA durante a ensilagem do capim-elefante favorece a fermentação e melhora o valor nutritivo das silagens, sendo recomendada em todos os níveis de inclusão avaliados. Palavras Elephant grass silage added with pineapple peelWe evaluated the qualitative, fermentative, and chemical characteristics of elephant grass silage containing different levels of inclusion of coproduct of the pineapple pulp extraction, pineapple peel -(0.0%, 12.5%, 25.0%, 37.5%, and 50.0%) in relation to natural field of elephant grass during ensiling. The material was ensiled in laboratory silos and after 180 days, the silos were opened and samples were collected for determination of dry matter, soluble carbohydrates, pH, ammonia nitrogen in percentage of total nitrogen, ether extract, crude protein, neutral detergent insoluble protein as a percentage of total nitrogen, acid detergent insoluble protein as a percentage of total nitrogen, neutral detergent fiber, acid detergent fiber, cellulose, lignin, neutral detergent insoluble nitrogen, acid detergent insoluble nitrogen, and in vitro digestibility of dry matter. To assess the effect of the treatments, we used a completely randomized design with four replications, running the regression analysis for each variable analyzed (P<0.05). According to the regression equations for the fermentative characteristics, the silages can be considered of very good quality. As for fiber digest...

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This study evaluate the impact of the reuse of the intravaginal progesterone implant (DIP), the body condition score and the racial composition on the pregnancy rate of Nelore and Angus heifers (F1) and Nelore cows of different categories submitted to different protocols of TAI, from a database of 3,093 females submitted to the same hormonal induction protocol and from the mating season of a commercial farm in the north of Minas Gerais. The racial com- position influenced the pregnancy rate of heifers, with rates of 55.11% for Nellore heifers and 64.36% for ½ Angus, showing that the ½ Angus breed has 1.55 times more chances of successful gestation compared to the breed Nellore. There is no effect of the progesterone implant until the third use on the pregnancy rate of the heifers evaluated. The increase of one unit in the body condition score on the scale of 1 to 5 implies 1.9109 or 91.09% times more success in pregnancy. The category of calving cows did not significantly affect the pregnancy rate in the evaluated herd, with pregnancy rates of 58.1%, 62.8%, 77.7% and 62.9% for primiparous, early primiparous, secondary and multiparous, respectively. The introduction of ½ Angus heifers to explore the effects of heterosis and complementarity between breeds is a viable alternative. Cows, when well managed in the postpartum period, obtain pregnancy rates higher than that observed in the national average.

The aim of this work was to evaluate the nutritional value of four sorghum-sudangrass hybrids harvested at four different stages of maturity. The hybrids evaluated were BR800, BRS810 (bmr), BRS802 and 156x2784. Hybrids were harvested at 52, 61, 67 and 74 days after seeding. BRS802 and BRS810 (bmr) are sorghum-sudangrass hybrids isogenic pairs that are distinguished only by the presence of bmr-6 mutation on BRS810. Samples were analyzed for dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL) content and in vitro DM and NDF digestibility (IVDMD and IVNDFD). Interaction between hybrid and stage of maturity was observed for NDF, ADF, IVDMD and IVNDFD. A linear increase in DM content was observed with increasing stage of maturity. A quadratic effect was observed for CP content with increasing stage of maturity, and the maximum CP value was estimated to be with 55.8 days. The hybrid BR800 had the highest CP content (12.5%) and the hybrids BRS 802 and 156x2784 the lowest CP content (9.7 and 10.3%, respectively) for all stages of maturity evaluated. A quadratic effect in NDF content was observed with increasing stage of maturity for the hybrids BR800, BRS810 (bmr) and BRS802 with the maximum values estimated to be with 62.0, 61.7 and 60.4 days after seeding respectively. With 52 and 67 days after seeding the hybrid BRS810 (bmr) had the lowest NDF content (64.2 and 66.4%, respectively). The isogenic pair, hybrids BRS802 and BRS810 (bmr), had a linear decrease in ADF content with increasing stage of maturity, and with 52, 61 and 67 days after seeding the bmr hybrid had lower ADF content compared to its counter pair (BRS802). No linear or quadratic effect with increasing stage of maturity was observed for ADL content. The hybrids BRS802 and 156x2784 had the highest ADL content (4.42 and 4.16%, respectively) regardless of the stage of maturity. BRS810 (bmr) had the lowest ADL content (2.49%) and intermediate value was observed for BR800 (3.69%). The hybrid BRS810 (bmr) had higher IVDMD and IVNDFD than its isogenic pair (BRS802) for all stages of maturity evaluated. The bmr-6 mutation increased the nutritional value of the sorghum-sudangrass hybrid through reduction in the NDF, ADF and ADL content and increases in CP, IVDMD and IVNDFD. Comparing the normal hybrids (non bmr), the hybrid BR800 stood out because of its lower ADF and ADL content and higher IVNDFD.

The purpose of the present study was to evaluate the principal component analysis (PCA) to guide technical assistance regarding several dairy farms’ issues, which includes improving microbiological quality and physical-chemical composition of raw refrigerated milk. Data of monthly analysis of fat, protein, lactose, dry defatted stratum, somatic cell count, total bacterial count, milk temperature of 8,101 samples of milk from expansion tanks and production of 78 farms located in the northern region of Minas Gerais, Brazil were processed. Descriptive statistical measures and Pearson correlation coefficient were estimated involving all evaluated traits during the dry and rainy seasons. In addition, multivariate analyses were performed using PCA. The results showed that two farm sites were negatively related to milk quality in both seasons. One farm stood out positively, being able to be used as a herd management model to drive technical assistance actions. Thus, PCA is efficient in simplifying large amounts of data, allowing simpler and faster technical herd management interpretation.

The bovine production on pastures is a sustainable activity, responsible to generating income and employments in many tropical regions. However, in this system a major obstacle occurs during long dry periods, when the forages show low nutritional quality. In this research we evaluated the in vitro digestibility and degradability of Urochloa decumbens and Cynodon dactylons var Tiffton 85 inoculated with isolates of Aspergillus spp. from the gastrointestinal tract cattle. Four cows with rumen fistula were used as rumen contents donors to determine the in vitro digestibility of dry matter (IVDMD). The treatments were, as follows: control - No fungal inoculum, AT13 – (with Aspergillus terreus isolate), AF69 – (with Asperillus fumigates isolate, MIX (with mix of fungi AT13 and AF69). The analyses were performed in rumen simulator with four replications. The gas production was determined by semi-automatic method for both gas and the mechanics ability to fiber colonization of these fungi isolates were evaluated by scanning electron microscopy. The inclusion of AF69 and MIX promoted significant increase of IVDMD of U. decumbens (41.4 - 42.1%). The dry matter degradability were not influenced by the inoculums types using the by semi-automatic gas production method However, they linearly increased with fermentation time.  The two isolates of Aspergillus spp. were able to colonize the U. decumbens fiber showing production of mycelium and reproductive structures in electronic microscopic analyses. The addition these Aspergillus isolates promotes significant increase of IVDMD to U. decumbens, indicating promising potential for development of microbial or probiotic additive to cattle raised on lignified tropical pasture.

Dairy farming has great socioeconomic importance in Brazil, and the last decades have registered a constant evolution of the production chain, seeking to increase quality and production efficiency. In this context, the production systems have intensified and adopted new technologies. The Compost Barn system has stood out as a confinement option for dairy cattle, for its lower implementation cost than other confinement systems and the possibility of giving an adequate destination to the animals' waste. Besides the search for greater production efficiency, the environmental sustainability of agricultural systems has been increasingly discussed, and dairy cattle farming is associated with many potential environmental impacts. It is essential to identify and mitigate them for the consolidation of a production chain socially fair, economically viable and environmentally correct. Thus, this literature review aims to evaluate the economic and environmental feasibility of the Compost barn system within the national dairy farming scenario.