Movement of livestock production within a country or region has implications for genetics, adaptation, well-being, nutrition, and production logistics, particularly in continental-sized countries, such as Brazil. Cattle production in Brazil from 1977 to 2011 was spatialized, and the annual midpoint of production was calculated. Changes in the relative production and acceleration of production were calculated and spatialized using ARCGIS®. Cluster and canonical discriminant analyses were performed to further highlight differences between regions in terms of cattle production. The mean production point has moved from the Center of Minas Gerais State (in the southeast region) to the North of Goiás State (in the Midwest region). This reflects changes in environmental factors, such as pasture type, temperature and humidity. Acceleration in production in the northern region of Brazil has remained strong over the years. More recently, “traditional” cattle-rearing regions, such as the south and southeast, showed a reduction in growth rates as well as a reduction in herd size or internal migration over the period studied. These maps showed that this movement tends to be gradual, with few regions showing high acceleration or deceleration rates.

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This meta-analysis evaluates the effects of yeast supplementation (Saccharomyces cerevisiae) on dry matter intake (DMI) and average daily gain (ADG) in beef cattle. The inclusion criteria were complete and randomized trials and supplementation with yeast S. cerevisiae versus no supplementation to measure DMI or ADG. Data were extracted from relevant papers via pre-defined protocols. A meta-analysis of random effects was conducted for each indicator separately including the mean of the control and treated groups. The results were presented with the pooled mean difference (MD), 95% of confidence interval, and I² (percentage of total variation between studies that is due to heterogeneity rather than chance). A total of 12 publications reporting 22 trials conducted in 1,161 cattle were analysed. The heterogeneity between studies was high and ranged from 92 to 99%. No effects were observed in ADG with the inclusion of yeast in the diet (MD = -2.849 g/day, p = 0.492). However, there was a reduction in the DMI (MD = -0.885 kg/day; p = 0.023) despite the high heterogeneity among studies (I 2 = 92.4%; p < 0.001). The ADG increased when the forage level in the diet was between 30 and 50% (MD = 641.08 g/day; p = 0.001) and decreased when the level range from 51 to 75% (MD = -2.90 g/day; p < 0.001). In over 60% of the Neutral Detergent Fibre, the use of yeast in the diet decreased the ADG by 406.94 g/day (p = 0.034). Feedlot animals showed a reduction in the DMI (MD = -0.97 kg/day; p = 0.019) if supplemented with yeast. Supplementation with S. cerevisiae in the diet of beef cattle had no effect on ADG; however, it does improve the feed conversion due to the reduction in DMI.

A systematic review (SR) and meta-analysis (MA) were performed to evaluate the effects of different energy levels (metabolizable energy, ME) and crude protein (CP), supplied to pregnant cows, on weight of their progenies at 60 (BW60), 100 (BW100), 180 (BW180) and 205 (BW205) days of age, average daily gain (ADG), and weight, age, loin eye area (LEA), marbling and fat thickness (FT) at slaughter. The SR was performed on two electronic databases. The MA for random effects was performed for each response variable separately. The BW60 was reduced (P<0.001; I 2 = 78.9%) when cows consumed CP and ME above the required levels during the third trimester of pregnancy (3TRI). The BW205 was lower (P<0.001; I 2 = 92.6%) when cows consumed ME above the recommended levels in the second trimester of pregnancy (2TRI) and 3TRI. Conversely, the ADG was higher when cows consumed CP (P = 0.032; I 2 = 96.1%) and ME (P<0.001; I 2 = 96.1%) above the required levels. The steers whose mothers consumed CP and ME above the required levels during the 3TRI were slaughtered 5.5 days earlier (P = 0.015; I 2 = 98.5%) compared to other steers. The marbling was higher (P<0.001; I 2 = 91.7%) in calves born to mothers consuming CP and ME above the recommended levels, regardless of the gestation phase. The FT was higher (P<0.001; I 2 = 0%) in the offspring of cows that consumed CP and ME above the required levels during the 3TRI. Thus, CP and ME intake, at levels higher than those recommended by the NRC, by pregnant cows in the 3TRI reduces the progeny weight up to 205 days of age. However, this is advantageous during the finishing phase, as it reduces slaughter age and increases the ADG and carcass quality by improving marbling and FT.