Determinou-se a qualidade nutricional de 26 rações para filhotes caninos comercializadas no Chile. As rações foram analisadas quimicamente e comparadas com as recomendações da American Association of Food Control Officials (AAFCO). Para as análises, utilizou-se uma amostra de cada ração, composta de pelo menos três lotes diferentes. Para cada amostra, foram determinados os conteúdos de matéria seca (MS), fibra, proteína bruta, aminoácidos essenciais, gordura, ácido linoléico e minerais. A energia metabolizável foi determinada mediante os fatores de conversão de Atwater e corrigida por sua densidade quando ultrapassava 4000kcal/kgMS. Todas as rações apresentaram conteúdos adequados de proteína, gordura, ácido linoléico, ferro, cobre, manganês e selênio. A concentração de triptofano foi adequada em 92,3% das rações, e a dos demais aminoácidos essenciais foi maior que a mínima recomendada. As maiores irregularidades foram encontradas no conteúdo de minerais, 92,3% das rações apresentaram uma adequada relação Ca:P. Foram observados níveis adequados de Ca, P e Mg em 96,2% das rações, de I em 92,3%, de Cl em 88,5%, de Na e Zn em 80,8% e de K em 34,6%. Em relação às concentrações de proteína, aminoácidos, gordura, ácido linoléico e minerais, somente 23% das rações apresentavam todas as especificações recomendadas pela AAFCO. A maioria das rações analisadas, (77%) apresentavam concentrações de nutrientes inferiores ao requerimento de filhotes caninos.

The nutritional quality of dry dogfood commercialized in Chile for growing dogs was studied. Samples from at least three different batches of 26 dogfood brands were mixed. The resultant samples (n=26) were chemically analyzed to determine their concentrations of dry matter (DM), gross energy, fiber, ash, crude protein, essential amino acids, total fat, linoleic acid and minerals. The metabolizable energy (ME) content of each sample was estimated using modified atwater factors. The results from the chemical analyses were compared with the nutrient profiles published by the American Association of Feed Control Officials (AAFCO). Dogfoods that were found to contain an estimated ME of over 4,000kcal/kg DM were corrected for their high energy density before comparison. All of the dogfoods contained adequate levels of protein, total fat, linoleic acid, iron, copper, manganese and selenium. The concentration of tryptophan was adequate in 92.3% of the samples. All of the other essential amino acids were present in adequate quantities. However, the situation was different for many of the minerals. Only 92.3% of the dogfoods contained an adequate Ca:P ratio. A total of 96.2% of the dogfoods contained an adequate level of Ca, 96.2% for P, 96.2% for Mg, 92.3% for I, 88.5% for Cl, 80.8% for Na, 80.8% for Zn and only 34.6% were adequate for K content. Overall, only 23% of the dogfoods evaluated in this study fulfilled all of the requirements established by the AAFCO in terms of their content of crude protein, amino acids, total fat, linoleic acid, and minerals. It appears that the majority of the dogfoods evaluated in this study (77%) would not satisfy all nutritional requirements of the growing dog.

The objective of the study was to determine the quantity of metabolizable energy (ME) in the dogfood amounts recommended by the manufacturers for commercial dry dogfoods formulated for adult dogs at maintenance and growing dogs, and compare these with the dogs’ calculated ME requirement. Commercial dry dogfood formulations for adult dogs at maintenance (15 brands) and growing dogs (15 brands) were evaluated. Samples from 3 batches per formulation were combined, ground and mixed with the indigestible marker Cr2O3. Each dogfood formulation for adult dogs was fed to 8 Labrador Retriever adult dogs and each formulation for growing dogs was fed to 8 growing Labrador Retriever dogs, for 8 days following 8 days in which the dogs received a nutritionally adequate base diet. Faecal samples were collected from each dog on days 6, 7 and 8 in which they received the test diets. The ME content of each diet was estimated and the quantity of ME in the amounts of the diets recommended by the manufacturers for adult dogs (10, 20 and 30 kg bodyweight) and growing dogs (12 and 24 kg bodyweight) was compared with the calculated ME requirements of these dogs. Depending on the size of the dogs, up to 80% of the brands recommended quantities of dogfood that would not supply the correct amount of ME according to the dog’s requirement. Feeding the dogs these quantities of the dogfoods may result in dogs that are significantly over- or under-weight.

El objetivo del estudio fue determinar el aporte de energía metabolizable (ME) de las dietas al ser suministradas en las cantidades recomendadas por los fabricantes de alimentos comerciales a perros adultos en mantención y en crecimiento y compararlas con los requerimientos energéticos del perro. Se evaluaron marcas comerciales de alimentos secos formulados para perros adultos en mantención (15 marcas) y perros en crecimiento (15 marcas). Se confeccionaron muestras compuestas a partir de 3 lotes por formulación, las que fueron molidas y mezcladas con el marcador indigestible Cr2O3. Cada dieta para perros adultos en mantención fue suministrada a 8 perros adultos y cada dieta para perros en crecimiento fue suministrada a 8 perros en crecimiento, todos de la raza Labrador Retriever, por un período experimental de 8 días, luego de 8 días en los cuales los perros recibieron una dieta base. Durante los días 6, 7 y 8 de cada período experimental se recolectaron muestras de fecas individuales. A cada dieta se le determinó la concentración de ME. El contenido de ME en las cantidades de las dietas recomendadas por las fabricantes de los alimentos en perros adultos (10, 20 y 30 kg peso vivo) y perros en crecimiento (12 y 24 kg peso vivo) fue comparado con los requerimientos de ME calculados para estos animales. Dependiendo del peso vivo considerado para los perros, hasta 40% y 40% de las marcas recomendaron cantidades de su alimento que suministran menos ME y más ME, respectivamente, que el requerimiento del perro. Alimentar a los perros con las cantidades recomendadas de alimento podría llevarlos a una condición corporal por debajo o por encima de la correcta.

The developmental stage of alfalfa (Medicago sativa L.) is an usual variable of study when evaluating cultivars because of its relationship with chemical composition and pasture growth rate. Determination of quantitative indexes such as "mean stage by count" and "mean stage by weight" (MSC and MSW respectively) makes it possible to describe the developmental phenological stages of alfalfa pastures in a more objective and reproducible way. Likewise, both the MSC and MSW indexes, describe the developmental stages of alfalfa when the pasture is close to the recommended utilisation time in practice. The advantage of estimating MSC in relation to MSW is based on the higher operative efficiency offered by the former in data generation for its calculation.

El estado de desarrollo de la alfalfa (Medicago sativa L.) es una variable de estudio común en evaluaciones de cultivares, dada su relación con la composición química y la tasa de crecimiento de la pastura. La determinación de los índices cuantitativos "estado medio por conteo" y "estado medio por peso" (EMC y EMP respectivamente) permite la descripción del estado de desarrollo en pasturas de alfalfa de una manera objetiva y reproducible. Los índices EMC y EMP describen igualmente el estado de desarrollo de la alfalfa cuando la pastura se encuentra próxima al momento de utilización recomendado en la práctica. La ventaja de estimar EMC en relación a EMP, se basa en la rapidez operativa que ofrece la generación de datos para el cálculo del primero.

The aim of the study was to evaluate, via chemical analysis, the nutritional quality of dry dogfoods commercially available in Chile for dogs in the stage of maintenance. For each of 33 brands of dogfood, samples were combined from three different batches and analyzed for dry matter (DM), gross energy, crude fiber, total ash, crude protein, essential amino acids, crude fat, linoleic acid and minerals. The metabolizable energy (ME) content was estimated from the results of the chemical composition using Modified Atwater Factors. The nutrient contents of the seven dogfoods that contained more than 4000 kcal/kg DM of ME were corrected for the high energy content of those foods. The results of the chemical analyses were compared with the values recommended by the American Association of Feed Control Officials (AAFCO). All of the dogfoods except one contained sufficient protein, and all of them except one contained sufficient amount of all of the essential amino acids. All of the foods contained sufficient crude fat, and all except one contained sufficient linoleic acid. All of the dogfoods evaluated contained adequate levels of phosphorus, sodium, chloride, iron, copper and manganese, but the situation was rather different for the other minerals. Two dogfoods contained inadequate levels of calcium (one too little the other too much), with an incorrect calcium to phosphorus ratio in seven dogfoods. A total of 13, seven, 12 and one dogfood contained insufficient potassium, zinc, iodine and selenium, respectively. Overall, only four of the 33 dogfoods evaluated contained adequate levels of protein, essential amino acids, fat (including linoleic acid) and minerals. Since five of the dogfoods that were not found to contain adequate levels of these nutrients have passed the AAFCO Feeding Protocols to establish adequate nutrition, in total only nine of the 33 dogfoods (27%) should provide adequate nutrition for dogs in maintenance.

El objetivo del estudio fue evaluar, a través de análisis químico, la calidad nutricional de alimentos secos disponibles comercialmente para perros adultos en etapa de mantención. Para cada una de 33 marcas de alimentos se mezclaron muestras de tres lotes distintos, y se analizaron: materia seca (MS), energía bruta, fibra cruda, cenizas totales, proteína cruda, aminoácidos esenciales, grasa cruda, ácido linoleico y minerales. El contenido de energía metabolizable (EM) de los alimentos se estimó a través de los Factores Atwater Modificados. En siete alimentos con un nivel de EM sobre 4000 kcal/kg MS se hizo una corrección a los contenidos de los nutrientes para tomar en cuenta la alta densidad energética. Se compararon los resultados de los análisis químicos con los valores recomendados por la American Association of Feed Control Officials (AAFCO). Todos los alimentos, menos uno, contenían suficiente proteína, y todos, menos uno, contenían suficiente de todos los aminoácidos esenciales. Había suficiente grasa en todos los alimentos, y todos los alimentos, menos uno, contenían un nivel adecuado de ácido linoleico. Había un nivel adecuado de fósforo, sodio, cloro, hierro, cobre y manganeso en todos los alimentos, pero la situación fue distinta para los otros minerales. Dos de los alimentos tenían un nivel inadecuado de calcio (uno demasiado bajo, el otro demasiado alto), con una relación calcio: fósforo incorrecta en siete alimentos. Un total de 13, 7, 1 y 12 alimentos contenía insuficiente potasio, zinc, selenio y yodo, respectivamente. En conjunto, solamente cuatro de los 33 alimentos evaluados en el estudio contenían niveles adecuados de proteína, aminoácidos esenciales, grasa, ácido linoleico y minerales.

This work was carried out in order to estimate the effects of a basic health programme (vaccination and helminth control) on wool production (fleece weight) and quality (fibre diameter and staple length) in sheep flocks of peasant farmers from different counties of the Province of Valdivia, 10th Region, Chile. 19 flocks with a total of 235 sheep were evaluated for each variable. Nine flocks were treated and 10 were used as controls, with at least 3 flocks per health treatment and county (Mafil, Lanco or Corral), in a factorial 2x3 randomized design. Least square mean for greasy fleece weight of the treated sheep (2.67 kg) was higher (p < 0 .01) than in control sheep (2.28 kg). An effect of location was also found (p < 0.01): Mafil sheep showed higher fleece weight (3.31 kg) than Corral sheep (2.25 kg), and these produced more than Lanco sheep (1.86 kg). The effect of the health programme was not apparent on staple length or fibre diameter, but location affected both variables. Staple length was positively correlated with fleece weight (0.293) and with fibre diameter (r=0.198)

En este estudio se consideraron 19 rebaños ovinos de pequeños agricultores de tres localidades de la provincia de Valdivia (comunas de Máfil, Lanco y Corral). Se evaluó el efecto de un sistema básico de salud (vacunaciones y desparasitaciones contra parásitos internos) aplicado en 1992 a nueve de estos rebaños, sobre el peso de vellón registrado en la esquila de fines de ese año, la longitud de mecha (regla graduada) y el diámetro de las fibras, obtenido de la lectura de 200 fibras por muestra (sector costal) en lanámetro Reichert. Se utilizaron al menos tres rebaños por tratamiento sanitario y por comuna, en un diseño completamente al azar con arreglo factorial de 2x3 (tratamiento sanitario x localidad), evaluándose un total de 235 ovinos para cada variable. El peso del vellón (PV) de las ovejas tratadas (2.67 kg) fue mayor (p< 0.01) que el de las controles (2.28 kg). A su vez, hubo efecto de localidad (p< 0.01): el PV en Máfil (3.31 kg) fue mayor que el de Corral (2.25 kg) y éste mayor al de Lanco (1.86 kg). No se detectaron efectos del programa sanitario sobre la longitud de mecha ni diámetro de fibras, pero sí hubo diferencias entre localidades para ambas variables. La longitud de mecha se correlacionó positivamente con el peso del vellón (r=0.293) y con el diámetro de fibras (r=0.198). Se concluye que el programa sanitario mejora la cantidad de lana producida, sin efectos en su calidad. También se apreciaron diferencias en la cantidad y calidad de lana producida por ovinos de distintas comunas, lo que podría deberse a la presencia observada de diferentes genotipos, o a otros efectos de carácter ambiental