[Show abstract][Hide abstract] ABSTRACT: Resumen
El control de garrapatas en sistemas ganaderos a través de sustancias acaricidas convencionales es cada vez menos efectivo debido a la capacidad de estos individuos para desarrollar resistencia. El uso de vacunas y hongos acaropatógenos articulados a programas de manejo integrado de parásitos – MIP, surgen como una alternativa para realizar un control eficaz de las garrapatas. En este trabajo, se evaluó la aplicación conjunta y por separado de un antígeno poliproteíco de R. microplus y una mezcla de hongos acaropatógenos en ganado en pastoreo. Se crearon 3 grupos de animales (n=9/grupo), a los cuales se les aplicó la vacuna y los hongos acaropatógenos de forma aislada y combinada; posteriormente se recolectaron las garrapatas ingurgitadas (>8mm) y se registraron sus parámetros reproductivos mensualmente por un periodo de 6 meses. Los resultados muestran que el peso (E.S) de las garrapatas obtenidas de los animales expuestos a la vacuna+hongos, fue significativamente mayor (P<0.05) que el de las expuestas a la vacuna solamente (151±10.5 mg versus 139.64±10 mg), pero no difirió del grupo tratado con los hongos (148.91±10.5). Dicha diferencia entre grupos también se observó para la masa de huevos, mas no se observaron diferencias con respecto al porcentaje de eclosión. De las vacas primíparas se obtuvieron garrapatas más pesadas en comparación con las de segundo y tercer parto (P<0.05). También se observó un ligero descenso (P<0.05) en los porcentajes de eclosión, cuanto mayores eran las temperaturas ambientales al momento de recolección. En conclusión, a pesar de que los resultados estadísticos muestran diferencias mínimas entre grupos, desde el punto de vista biológico serían irrelevantes ya que todos los parámetros evaluados se encontraron dentro de los valores normales para la especie.
Reproductive performance of Rhipicephalus microplus from cattle treated with a polyproteic vaccine and an acaropathogenic fungal suspension
Tick control in livestock systems turns in a less effective activity because of ticks capability to develop resistance to acaricides. The use of vaccines and acaropathogenic fungi articulated to integrated parasite management programs appears as an alternative for the effective control of tick populations. In this work, the combined and separated application of a poliproteic antigen of R. microplus, and a suspension of acaropathogenic fungi over naturally infested cattle was assessed. Three groups of animals were stablished (n=9 per group) and the products were applied separately and combined according to the group; later, ticks bigger than 8 mm were collected and their reproductive parameters registered monthly for a six month period. Results shown that the weight of ticks obtained from animals exposed to the vaccine+fungi combination was significantly higher (p<0.05) than ticks exposed only to the vaccine (151±10.5 mg versus 139.64±10 mg), and have no differences with the fungi group (148.91±10.5). Results were similar for the egg mass weight, and shown no treatment effect over the hatching percentage (p=0.7222). The cows of first parturition had the heaviest ticks compared with those of second and third parturition (p<0.05). A slight decrease of the hatching percentage was also observed with the increase of the environmental temperature at the collection time. Nevertheless, statistics shown minimal differences between groups, they are considered biologically irrelevant, because all the parameters assessed in this study fit in the normal values for the specie.
[Show abstract][Hide abstract] ABSTRACT: La resistencia generada por las garrapatas a los acaricidas es un problema que limita el control de las infestaciones de manera efectiva, aumenta los costos de producción en ganadería, y que tiene implicaciones negativas por el deterioro que ocasionan los agroquímicos sobre el medioambiente y la salud de operarios y consumidores. Los programas de manejo integrado de parásitos (MIP), promueven el uso de estrategias que reduzcan al mínimo la dependencia de acaricidas químicos, entre algunas, se pueden mencionar el uso de vacunas antigarrapata y hongos acaropatógenos. En este estudio se buscó evaluar el posible efecto combinado de la vacuna comercial TickVac con una suspensión comercial (Bioplag) a base de Metarrihizum anisopliae y Beauveria bassiana de uso tópico, sobre el control de Riphicephalus microplus en bovinos. Para tal fin, se seleccionaron 27 bovinos de la raza criolla colombiana Lucerna, manejados en sistemas silvopastoriles, que se dividieron en tres grupos de 9 animales cada uno, a los que se aplicó la vacuna (días 0, 20 y 60), hongos (días 0, 20,40 y 60), o ambos productos combinados. Cada dos semanas durante 6 meses se contaron el número total de garrapatas mayores a 5mm en cada animal. Se observó una gran fluctuación de las cargas parasitarias en todos los grupos durante el periodo de estudio; sin embargo, los valores promedio (E.S) a lo largo de este fueron de tan solo 10.22.4, 11.92.4, y 11.62.4 para los grupos de vacuna, hongos y combinación, respectivamente. Las bajas cargas parasitarias durante todo el muestreo fueron una limitación para detectar posibles efectos de los tratamientos sobre el nivel de infestación. No obstante, el hecho de que se presentara una fluctuación similar en todos los grupos sugiere que las cargas parasitarias estaban reflejando una dinámica natural de infestación que no se afectó con ninguno de los tratamientos empleados.
Trials with a polyproteic vaccine and an acaropathogenic fungal supension in cattle naturally infested by Rhipicephalus microplus.
Resistance developed by ticks to acaricides limits an effective infestation control, increasing loses to livestock producers and having negative implications on the environment and human health due to increased use of pesticides. In the framework of an integrated parasite management, the use of strategies like anti-tick vaccines and acaropathogenic fungi is promoted to reduce dependence on chemical acaricides. The present study evaluated the potential additive effect of both strategies when applied combined to reduce tick numbers in cattle. To this end, 27 cows of the creole breed Lucerna, under silvopastoral conditions were selected and divided in three groups as follows: vaccine (days 0, 20 and 60), fungi (days 0, 20, 40 and 60) and the combination of both. Every two weeks, for a period of six months the total number of ticks over 5mm was counted on each animal. A great fluctuation in tick numbers was observed throughout the study in all groups; the means (±S.E.) were 10.22.4, 11.92.4, and 11.62.4 for the vaccine, fungi and their combination, respectively. The low counts of ticks throughout the study were a mayor limitation to detect any potential effect of treatment. However, a similar fluctuation of tick counts in all groups suggests that the pattern of natural infestation was not influenced by any of the treatments.
[Show abstract][Hide abstract] ABSTRACT: High-quality colostrum is an important factor influencing neonatal calf health, and quality assessment is essential to obtain good health results. This research evaluated the effects of the calf's sex, the parity of the cow and the hour of colostrum harvest after parity on the fat, nonfat solids, protein and Ig contents in Holstein colostrum for cows under high grazing conditions in the tropics. The effects of the calf's sex and parity on somatic cell count (SCC) at the first milking postpartum were determined. A comparison was made between a laboratory method and a farm method for the estimation of the fat and protein content of colostrum. Thirty-three cows were sampled in the study. The calf's sex was shown to have an effect on the amount of colostrum, on the concentration of fat, and on the amount of milk produced by lactating Holstein cows; all were higher in cows that gave birth to a female calf. Colostrum protein decreased after the first hour postpartum, and the Ig concentration had a tendency to decrease after 4 h. The cows that had parity 1-2 had lower Ig concentrations and total production of Igs, and higher SCC at the first milking postpartum. Ekomilk was a reliable method to measure the colostrum fat on the farm.
No preview · Article · Feb 2015 · Tropical Animal Health and Production
[Show abstract][Hide abstract] ABSTRACT: Background: milk fatty acid composition has become very important for consumers due to the positive relationship that has been found between some fatty acids and human health. In recent years, content and fatty acid composition in the different fractions of milk lipids has also become important due to reported potential technological and sensory implications. Objective: the aim of this study was to evaluate the effect of dietary supplementation with several lipid supplements on the proportion of neutral (triglycerides) and polar lipids (phospholipids) of milk fat, alterations of the fatty acid composition and Conjugated Linolenic Acid isomers (CLA) of total milk lipids. Methods: 18 first lactation German Holstein cows were assigned to three dietary treatments for 10 weeks as follows: Rumen-stable fractionated palm fat, linseed oil plus algae, and sunflower oil plus algae. Results: dietary polyunsaturated fat supplements increased the proportion of phospholipids and decreased triglycerides in milk fat compared to Rumen-stable fractionated palm fat. Long chain polyunsaturated fatty acids were preferentially deposited into phospholipids. Diet effect was more pronounced in triglycerides than in phospholipids. Plant oil/algae supplemented diets induced lower proportions of total saturated fatty acids and higher proportions of total unsaturated fatty acids in triglycerides. Conclusions: linseed oil plus algae feeding generated the best results in reference to fatty acids related to human health. Sunflower oil plus algae caused accumulation of CLAtrans-10,cis-12, CLAtrans-7,cis-9, CLAtrans-7,trans-9 and CLAtrans-10,trans-12 and decrease of CLAtrans-9,trans-11 in total milk fat, whereas linseed oil plus algae increased CLAtrans-12,trans-14, CLAtrans-11,trans-13, and CLAtrans-11,cis-13 deposition compared to rumen-stable fractionated palm fat.
Full-text · Article · Jun 2013 · Revista Colombiana de Ciencias Pecuarias
[Show abstract][Hide abstract] ABSTRACT: The effect of a 10-week supplementation with polyunsaturated fatty acids [via sunflower oil/DHA-rich algae (SUNA) or linseed oil/DHA-rich algae (LINA) enriched diets] versus saturated fatty acids (SAT) of lactating German Holstein dairy cows in mid-lactation on expression patterns of lipid metabolism-associated genes and gene products in hepatic, longissimus muscle and subcutaneous/perirenal/omental adipose tissue was assessed. Most pronounced transcriptomic responses to dietary PUFA were obtained in hepatic [down-regulated ACACA (FC = 0.83, SUNA; FC = 0.86, LINA), FADS1 (FC = 0.60, SUNA; FC = 0.72, LINA), FADS2 (FC = 0.64, SUNA; FC = 0.79, LINA), FASN (FC = 0.64, SUNA; FC = 0.72, LINA), SCD (FC = 0.37, SUNA; FC = 0.47, LINA) and SREBF1 (FC = 0.79, SUNA, LINA) expression] and omental adipose [up-regulated ACACA (FC = 1.58, SUNA; FC = 1.22, LINA), ADFP (FC = 1.33, SUNA; FC = 1.32, LINA), CEBPA (FC = 1.75, SUNA; FC = 1.40, LINA), FASN (FC = 1.57, SUNA; FC = 1.21, LINA), LPL (FC = 1.50, SUNA; FC = 1.20, LINA), PPARG (FC = 1.36, SUNA; FC = 1.12, LINA), SCD (FC = 1.41, SUNA; FC = 1.17, LINA) and SREBF1 (FC = 1.56, SUNA; FC = 1.18, LINA) expression] tissue. Interestingly, gene/gene product associations were comparatively low in hepatic and omental adipose tissue compared with longissimus muscle, perirenal adipose and subcutaneous adipose tissue, indicating matches only in regard to minor concentrations of SCD product 18:1c9, FADS1 product 20:4n-6 and FADS2 product 18:3n-6 in hepatic tissue, and higher concentrations of ACACA and FASN gene products 12:0 and 14:0 and SCD product 18:2c9,t11 in omental adipose tissue. Whereas all analyzed tissues accumulated dietary PUFA and their ruminally generated biohydrogenation products, tissue-divergent preferences for certain fatty acids were identified. This descriptive study reports tissue-divergent effects of dietary PUFA and outlines the significance of a PUFA intervention with regard to dairy cows' nutritional management.
[Show abstract][Hide abstract] ABSTRACT: The main aim of the present study was to examine the effects of long-term supplementing diets with saturated or unprotected polyunsaturated fatty acids from two different plant oils rich in either n-3 or n-6 fatty acids (FAs) plus docosahexaenoic acid (DHA)-rich algae on mammary gene expression and milk fat composition in lactating dairy cows. Gene expression was determined from mammary tissue and milk epithelial cells. Eighteen primiparous German Holstein dairy cows in mid-lactation were randomly assigned into three dietary treatments that consist of silage-based diets supplemented with rumen-stable fractionated palm fat (SAT; 3.1% of the basal diet dry matter, DM), or a mixture of linseed oil (2.7% of the basal diet DM) plus DHA-rich algae (LINA; 0.4% of the basal diet DM) or a mixture of sunflower oil (2.7% of the basal diet DM) plus DHA-rich algae (SUNA; 0.4% of the basal diet DM), for a period of 10 weeks. At the end of the experimental period, the cows were slaughtered and mammary tissues were collected to study the gene expression of lipogenic enzymes. During the last week, the milk yield and composition were determined, and milk was collected for FA measurements and the isolation of milk purified mammary epithelial cells (MECs). Supplementation with plant oils and DHA-rich algae resulted in milk fat depression (MFD; yield and percentage). The secretion of de novo FAs in the milk was reduced, whereas the secretion of trans-10,cis-12-CLA and DHA were increased. These changes in FA secretions were associated in mammary tissue with a joint down-regulation of mammary lipogenic enzyme gene expression (stearoyl-CoA desaturase, SCD1; FA synthase, FASN) and expression of the regulatory element binding transcription factor (SREBF1), whereas no effect was observed on lipoprotein lipase (LPL) and glycerol-3-phosphate acyltransferase 1, mitochondrial (GPAM). A positive relationship between mammary SCD1 and SREBF1 mRNA abundances was observed, suggesting a similar regulation for these genes. Such data on mammary gene expression in lactating cows presenting MFD contribute to strengthen the molecular mechanisms that govern milk fat synthesis in the mammary glands. In purified MEC, the dietary treatments had no effect on gene expressions. Differences between mammary tissue and milk purified MEC gene expression were attributed to the effect of lipid supplements on the number of milk purified MEC and its RNA quality, which are determinant factors for the analysis of gene expression using milk cells.
[Show abstract][Hide abstract] ABSTRACT: Organic waste from markets represents about 10-20% of the total waste of a city. A large proportion comes from the overproduction of fruit and vegetables, turning them into potential pollutant. The nutritional value found for fruit and vegetable waste (FV) from a marketplace, in a previous work, showed that this product might be considered as a potential alternative for animal feeding. This study evaluated the use of FV as feedstuff for diets of lactating Holstein cows with an emphasis on milk yield and quality. FV was included in 0, 6, 8, 12, and 18% of the concentrate. A 4 x 4 Latin squares model was used to analyze data (4 animal groups, 4 periods of evaluation, and 4 treatments). No statistical differences in milk yield per kilogram of eaten concentrate or concentrate intake were recorded between groups fed FV and the control group. There was a significant effect of the treatment on cis-9,trans-11 CLA and α-linolenic acid content in milk. These results showed that FV can be used as a dietary ingredient for high-yield lactating cows without detriment in the milk yield and with improvement in the milk quality. FV could be included at proportions of between 6% and 18% in the concentrate, as long as the animal's dietary requirements are covered. The main impact of these results is the alternative generated for the improvement of the environment.
No preview · Article · Jul 2011 · Journal of Environmental Management
[Show abstract][Hide abstract] ABSTRACT: The present study investigated the effect of three different dietary fats [saturated fat (SAT) (3.1% TMR DM); linseed oil (LINA) (2.7% TMR DM) or sunflower oil (SUNA) (2.7% TMR DM) added with docosahexaenoic acid rich algae (0.4% TMR DM)] on SREBP-1 protein expression in mammary gland tissue of German Holstein cows (n=18) in the context of milk yield, milk fat content and milk fatty acid composition. Prerequisite for this investigation was the development of a Western blot methodology adapted for bovine mammary gland tissue using two different primary antibodies to specifically detect and differentiate between precursor (pSREBP-1, 125kDa) and transcriptionally active SREBP-1 (mSREBP-1, 68kDa).Upon a ten-week feeding intervention, significantly reduced milk fat contents, total saturated fatty acid amounts and single saturated fatty acid concentrations (C10:0, C12:0, C14:0, C16:0) were obtained in LINA and SUNA group, whereas milk yields did not substantially differ between feeding groups. The assumption that the effects of plant oil/DHA rich algae supplementation on milk fat composition were mediated by shifted SREBP-1 protein expression were only confirmed in regard to slightly reduced protein expression levels of pSREBP-1 in SUNA group tissue samples (P=0.087), whereas similar protein expression levels of transcriptionally active mSREBP-1 were found in SAT, LINA and SUNA group.
Full-text · Article · Jan 2011 · Livestock Science
[Show abstract][Hide abstract] ABSTRACT: There are different sources for the generation of solid waste, and marketplaces are considered one of them. Fruit and vegetable waste (FV) from a marketplace in Colombia was quantitatively and nutritionally characterized to contribute to its use in bovine feeding and to contribute minimizing its environmental impact. The evaluation was carried out 7 days per week during 4 periods of the year. FV was grouped by cluster analysis using SAS(®) 2006. FV was composed of 43% fruit, 30% vegetables and 27% stems, leaves, leaf wrappers, corncobs, roots, refuse and others. FV was defined in four main groups. On average, FV contained 10% crude protein (CP), 36.6% neutral detergent fiber (NDF), 29.6% acid detergent fiber (ADF), 87.8% ruminal degradability at 24 h, 3657 kcal/kg, 0.59% calcium (Ca(+2)), and 0.21% phosphorous (P). There were no statistical differences between days or between periods of evaluation (p > 0.05) for CP or for Ca(+2). As for NDF and ADF, there were statistically significant differences between periods but not between days. The microbiological parameters only increased when the humidity was up to 12%. FV represents a potential feedstuff for bovine feeding, and its recycling could avoid the discharge of a large amount of waste to landfills, which would minimize its environmental impact.
No preview · Article · Jan 2011 · Journal of Environmental Management
[Show abstract][Hide abstract] ABSTRACT: This study was conducted to evaluate if supplementing bypass fat to cows under silvopastoral systems, increases the concentration of unsaturated fatty acids in milk, thus improving the saturated/ unsaturated ratio without a negative effect on total milk yield in fat or protein. Two concentrations of two different sources of bypass fat were evaluated for 40 days, each in a group of 24 multiparous Lucerna (Colombian breed) cows. A cross-over design of 8 Latin squares 3 x 3 was used. The variables submitted to analysis were body condition, daily milk production and milk composition. Body condition, milk yield and milk quality were not different but there was a significant decrease in the amount of saturated fatty acid in both experiments while the unsaturated fat increased significantly in experiment 1 and remained stable in experiment 2. Results, such as these have as far as we know, not been reported previously and they provide an approach for the improvement of milk as a "functional food".
Full-text · Article · May 2008 · Tropical Animal Health and Production
[Show abstract][Hide abstract] ABSTRACT: Se estimó el efecto que tiene la suplementación de la grasa protegida al rumen durante el periodo de amamantamiento (7 meses con presencia permanente del ternero). Se usaron 30 vacas de primer parto Angus x Cebú (A x C) y 18 Cebú (C). Se llevó un registro de la condición corporal y el peso de las madres y también del peso de los terneros. La suplementación terminó con el destete de los terneros. Las vacas y los terneros pastaban en brachiarias (Mezclas de Brachiaria decumbens y Brachiaria humidicola), que ofrecía entre 1587 kg de materia seca verde (MSV) durante el periodo de lluvias (Agosto a Noviembre), 175 kg MSV en la época de transición y periodo seco (Diciembre a Abril). Los datos que corresponden a cada grupo genético se analizaron independientemente durante todo el período experimental y de forma conjunta durante los primeros 90 días de lactancia, usando un modelo mixto de medidas repetidas. Las vacas C suplementadas (n=12), así como sus controles (no recibían grasa sobrepasante) perdieron peso durante los 7 meses del experimento, pero mantuvieron una mejor condición corporal los primero 4 meses posparto (p<0.05). Las vacas AxC (n=20) ganaron peso durante los primeros tres meses después del parto y mantuvieron la condición corporal mejor que sus controles, (sin grasa sobrepasante) (p<0.01); después las vacas AxC comenzaron a perder peso y condición corporal (CC) (p<0.05) pero siempre los parámetros
se mantuvieron por encima de las vacas control. No se observó ningún efecto del tratamiento de las adres, en los terneros. Se concluye que ofreciendo grasa sobrepasante como suplemento durante la lactancia de vacas de primer parto amamantando el ternero, se mejoran las reservas corporales de las vacas F1, pero no se tiene un efecto marcado en las vacas Cebú, ni en los terneros de ningún grupo.
[Show abstract][Hide abstract] ABSTRACT: It was estimated the effect of rumen protected fat during the suckling period (7 months with the permanent presence of the calf), in 30 Angus/Zebu (AxZ) and 18 Zebu (Z) first calving cows. Mothers body weight and body condition (BC) were recorded. The weight of calves was also analyzed. Supplementation finished at weaning. The cows and the calves grazed on brachiaria (mixture of Brachiaria decumbens y Brachiaria humidicola) with amounts of dry green matter (DGM) varying from 1587 kg DGM/ha during the rainy period (August to November) to 175 kg DGM/ha in the transition and the dry period (December to April). The data corresponding to each genetic group were analyzed independently using a mixed model with repeated measurement data. Supplemented Z cows (n=12) as well as their controls (Z cows not receiving bypass fat) lost weight all along the seven months suckling but maintained a better BC up to the fourth month after parturition (p
[Show abstract][Hide abstract] ABSTRACT: The foliage yield of Acacia mangium in a pasture system was evaluated according to three harvesting intervals (40, 60 y 80 days) during the dry and rainy season. The results showed that Acacia mangium Willd presented better recovery at the time of rains than in the dry season and that foliage yields were higher when the harvest frequency was extended to 80 days.