Relationship between two methods of heat detection and reproductive efficiency in Holstein cows

El objetivo del estudio fue evaluar dos métodos de detección del celo en dos épocas del año y su influencia sobre la eficiencia reproductiva de vacas Holstein. Se evaluaron 1445 registros de un establo comercial de explotación intensiva ubicada en el norte de Lima, Perú en 2014. Los métodos de detección de celo fueron un medidor de actividad comercial (T1), la observación visual (T2) y la combinación de ambos métodos (T3). Los parámetros reproductivos evaluados fueron la tasa de detección de celos, la tasa de concepción, el número de servicios por concepción, los días abiertos y el número de parto. El mayor número de celos fue detectado con T3 (52.2%) en comparación al 27.5% de T1 y al 20.2% de T2 (p<0.05). T1 fue más eficiente en la detección de celos durante el verano (34.7% de celos) en comparación con T2 (13.2%) (p<0.05). T1 detectó mayor número de celos en la primera y segunda lactación (30.3 y 26.5%, respectivamente) en comparación con T2 (20.0 y 19.7%, respectivamente) (p<0.05). No hubo diferencia significativa entre tratamientos con relación a la tasa de concepción y número de servicios por concepción; sin embargo, se encontró un menor número de días abiertos en servicios hechos en celos detectados por observación visual (117 días) en comparación con aquellos por el medidor de actividad (144 días). Se concluye que el medidor de actividad es más eficiente que la observación visual en la detección de celos; sin embargo, los mejores resultados se obtienen combinando ambos métodos.The objective of the study was to evaluate two methods of detection of oestrus in two seasons and their influence on reproductive efficiency in Holstein cows. A total of 1445 records was evaluated from an intensive commercial farm located in the north of Lima, Peru in 2014. The methods of detection of oestrus were a commercial activity meter (T1), visual observation (T2) and the combination of both methods (T3). The reproductive parameters evaluated were the rate of heat detection,  conception rate, number of services per conception, open days and parity number. The highest number of heats was detected with T3 (52.2%) compared to 27.5% of T1 and 20.2% of T2 (p<0.05). T1 was more efficient in detecting heats during the summer (34.7% heats) compared to T2 (13.2%) (p<0.05). T1 showed a higher number of heats in the first and second lactations (30.3 and 26.5%, respectively) compared to T2 (20.0 and 19.7%, respectively) (p<0.05). There was no significant difference between treatments in relation to conception rate and number of services per conception; however, a lower number of open days in services made in heats detected by visual observation (117 days) were found compared to those by the activity meter (144 days). It is concluded that the activity meter is more efficient than the visual observation in the detection of heats; however, the best results are obtained by combining both methods

Extraction from woody forest plants in flood plain communities in Amazonian Peru:use, choice, evaluation and conservation status of resources

The extraction and use of materials from woody forest species in communities along the lower Ucayali river in Amazonian Peru is discussed distributed at the categories food, construction, technical uses, medicine and commerce, represented with 5, 8, 11, 12 and 7 uses for specific purposes, respectively. The amounts of materials extracted are compared with the evaluation of the same resources. Three methods served to quantify the extraction, namely (1) recording of the plant-resources extracted by 12 households during a 1-year-long study; (2) observations of peoples activities in the forests and elsewhere and (3) recording of originally extracted materials present in or near the houses of 42 households. Two methods served to evaluate local perceptions of these materials, namely (4) village studies mostly of medicinal plants selected and described by informants and (5) forest plot-studies. Informants were interviewed on the potential uses of 276 pre-selected tree and liana species. Main conclusions are (1) probably all local tree and liana species may be used, but among thousands of potential uses only 291 uses of 156 species were found to be extracted frequently and/or evaluated to be particularly useful in interviews; (2) the importance interviewed informants give to forest resources does often not correlate with how often they extract them; (3) forest types vary much in their potential to provide extracted products, mostly in accordance with floristic compositions; (4) for nearly all purposes the population extracts from a few preferred species constituting a small percentage of the trunks in the forests, while more species representing a larger share of the trunks are recognised as potentially useful; (5) nearly all extracted plant-resources important for the livelihood of the population can be replaced with materials from other local species reducing the consequences of depletion and (6) an intensive exploitation mainly for commerce has depleted local populations of 10 plant species, and 15 species may currently get depleted