This study was conducted in Toacaso Town in the northwest of Latacunga City, Cotopaxi Province, Ecuador. The researchers aimed to establish in situ the optimal age and cutting time of REMINGTON ...Ryegrass (Lolium perenne) based on the concentration of soluble carbohydrates using a digital refractometer. The research used 48 experimental units, each with an area of 16 m2 (4×4 m) and a total area of 768 m2. The experiment was carried out for 60 days in which the highest concentration of carbohydrates was evaluated taking into account (i) the age of the pasture – 45 and 60 days (factor A) and (ii) the cutting time – 08H00, 10H00, 12H00, 14H00, 16H00, and 18H00 hours (factor B0) for which a randomized complete block design (RCBD) was used under a bifactorial arrangement with four repetitions per treatment. The results reported that the highest concentration of soluble carbohydrates was obtained at 60 days of age with 13.15º Brix (ºBx), while the optimal cut-off time was 2:00 p.m. with a concentration of 16.33 ºBx. The authors conclude that the older the pasture, and considering the time of the day, the higher the concentration of soluble carbohydrates will be. The highest cost-benefit was obtained at 4:00 p.m. presenting a cost-benefit of $1.44 which means that for every dollar invested a profit of 44 cents was obtained. Therefore, it is recommended to harvest the REMINGTON Ryegrass at 60 days of age at 2:00 p.m.
Keywords: soluble carbohydrates, Ryegrass (Lolium perenne), remintong, digital refractometer, Brix degrees.
RESUMEN
Se estableció in situ la edad y hora de corte óptima sobre la concentración de carbohidratos solubles en un Rye grass tetraploide (Lolium perenne) variedad REMINTONG, mediante la utilización de un refractómetro digital en la parroquia Toacaso ubicada al noroccidente del cantón Latacunga, provincia de Cotopaxi. En la investigación se utilizó 48 unidades experimentales con un área de 16 m2 (4 m x 4 m), en una superficie total de 768 m2. El trabajo experimental tuvo una duración de 60 días en los cuales se e valuó la mayor concentración de carbohidratos con relación a la edad del pasto 45 y 60 días (factor A), y la hora de corte 08H00, 10H0 0, 12H00, 14H00, 16H00 y 18H00 horas (factor B), para lo cual se aplicó un Diseño de Bloques Completamente al Azar (DBCA) bajo arreglo bifactorial con cuatro repeticiones por tratamiento. Los resultados reportaron que la mayor concentración de carbohidratos solubles se obtuvo a los 60 días de edad con 13,15 grados Brix (∘Bx), relacionados con la hora de corte optima que fue a las 14h00 con una concentración de 16,33 ∘Bx, concluyendo que a mayor edad y conforme la hora del día, mayor será la concentración de carbohidr atos solubles. El mayor beneficio costo se obtuvo a las 16h00 presentando un beneficio/costo de $ 1,44 USD, lo que quiere decir que por cada dólar invertido se obtuvo una ganancia de 44 centavos, por lo tanto, se recomienda cosechar el pasto Rye grass variedad REMINGTON a los 60 días de edad a las 14h00.
Palabras Clave: Carbohidratos Solubles, Rye grass (Lolium perenne), Remintong, Refractómetro digital, grados brix.
There is an increased interest in using digital refractometers to indirectly assess colostrum quality of dairy cattle, but knowledge on diagnostic accuracy for Norwegian Red dairy cows is lacking. ...Recent research has indicated a profound variability in the colostrum quality among dairy cows and herds in Norway. The aim of this study was to evaluate the diagnostic test sensitivity and specificity of a digital refractometer (Brix refractometer) at different cut-offs in Brix% for detection of colostrum of high quality (> 50 g/L) defined by the gold standard single radial immunodiffusion (IgG g/L). Furthermore, we aimed to identify possible associations between selected herd and cow-level management factors and colostrum IgG-levels in Norwegian Red dairy cows.
Median colostrum IgG level across 167 cows from 19 herds was 35.0 g/L, ranging from 5 to 129 g/L. Mean Brix% (± SD) was 19.7 ± 4.12%, ranging from 10.1 to 30.5. Most samples (72.5%) had inferior quality as compared to the international standard of 50 g/L. Brix% and IgG in colostrum were strongly correlated (r = 0.71, P < 0.001). A Brix cut-off of 22%, which is currently recommended, yielded a sensitivity of (95% CI) 69.4% (54.6-81.7) and a specificity of 83.1% (75.0-89.3) for identifying colostrum with high quality (> 50 g/L). The only factor found to be associated with low colostrum quality was parity. Specifically, cows in the second parity were found to produce colostrum with low quality compared to cows in parities four and later.
The agreement between colostrum IgG and Brix% is good. However, the diagnostic test evaluation indicates suboptimal performance in identifying high vs. low colostrum quality in this population, possibly related to a high proportion of the samples with < 50 g/L IgG. The only factor found to be associated with low colostrum quality was parity. Specifically, cows in the second parity were found to produce colostrum with lower quality. Future research should investigate colostrum and serum IgG levels which best prevent calf illness under Norwegian conditions.
In this paper, we propose the development of a highly stable and low-cost refractometer for measuring the sucrose concentration. Laboratory-grade refractometers are prohibitively costly and ...impractical for everyday applications, while currently accessible low-cost commercial alternatives suffer from insufficient stability and precision. To address this gap, our proposed refractometer replaces the costly CCD sensor and light source with a conventional LED and a cost-effective CMOS sensor. By analyzing the output waveform pattern, we achieve high precision with an accuracy of 0.1%, which is suitable for individual use. We repeat 100 measurements on various samples to determine the dependability and consistency of our refractometer, and the results demonstrate its accuracy. The algorithm operates on a 480 MHz ARM processor and acquires data within 20mS. Our instrument provides an affordable and reliable method for measuring sucrose concentration and demonstrates stability and accuracy compared to existing cost-effective options.
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