RESUMO
With the objective of evaluating the quality parameters of raw milk in Ecuador between 2010 and 2020, a systematic review and meta-analysis of 73 studies on raw milk produced in different regions of Ecuador was performed. Under the random effects model, effect size and heterogeneity were determined vs. climatic region both among analyses and studies, with Cochran's Q, I2 and Tau (π) statistics. For all the variables, it was observed that there was great heterogeneity (I2 > 90%) among the studies; additionally, it was found that climatic region had an influence only among the variables arsenic, mercury, pH and total solids, and it was greater in the coastal region than the Inter-Andean region. The mean values of the physicochemical characteristics of the milk (titratable acidity, ash, cryoscopy, fat, lactose, pH, protein, non-fat solids and total solids) in the great majority of these studies were within the range allowed by Ecuadorian regulations. As for the hygienic quality of raw milk (total bacterial count, somatic cell count and presence of reductase), although the mean values were within those determined by local legislation, it should be noted that the range established by Ecuadorian regulations is relatively much higher compared to other regulations, which possibly means that there is a high presence of bacteria and somatic cells in raw milk. Finally, the presence of several adulterants (added water) and contaminants (AFM1, antibiotics and heavy metals) was confirmed in the milk, in addition to other substances such as eprinomectin, zearalenone and ptaquilosides, whose presence can be very dangerous, because they can be hepatotoxic, immunotoxic and even carcinogenic. In conclusion, there is great variability among the studies reviewed, with the physicochemical characteristics being the most compliant with Ecuadorian legislation; the hygienic characteristics, adulterants and contaminants of raw milk require greater attention by producers and local authorities, so that they do not harm the health of consumers and the profitability of producers in Ecuador.
RESUMO
Foi pesquisada a influência da suplementaçäo com cromo (Cr) sobre a concentraçäo plasmática de cortisol, uréia, cálcio e fósforo em vacas zebu mantidas a pasto e numa situaçäo de estresse calórico durante a estaçäo de monta. Foram utilizadas trinta vacas primíparas com peso entre 380 e 385kg. Os animais foram divididos em grupos de 15 vacas, formando o tratamento suplementado com Cr e o tratamento näo suplementado (controle). As vacas pastorearam em piquetes formados por Brachiaria brizanta cv. Marandu. A fonte de Cr foi levedura enriquecida (1g Cr kg-1 de produto comercial) e foi adicionado à mistura mineral aportando 0,017 por cento de Cr. Amostras de sangue foram tomadas em três períodos através de venipunçäo jugular e coletadas em tubos contendo heparina. As amostras de plasma foram analisadas para fósforo, cálcio, uréia e cortisol. Os dados foram analisados como um desenho de blocos ao acaso. O consumo médio diário de mistura mineral foi de 72,92g no grupo suplementado com Cr (12,40mg Cr/cabeça/dia) e 77,84g no grupo controle (0,78mg Cr/cabeça/dia). A concentraçäo plasmática de cortisol, no grupo suplementado com Cr, foi menor que no tratamento controle (2,11mg dl-1 vs. 3,29mg dl-1). As concentraçöes plasmáticas de fósforo (6,36mg dl-1 vs 3,56mg dl-1) e de cálcio (12,87mg dl-1 vs 9,02mg dl-1) foram maiores no grupo suplementado com Cr durante o primeiro período, mas näo existiram diferenças no segundo e terceiro períodos de colheita. Os níveis plasmáticos de uréia (17,13mg dl-1 vs. 17,70mg dl-1) näo foram diferentes entre os grupos experimentais
