Variables inherent to the forage and animal component were evaluated to design feed profiles of dual-purpose cows grazing Panicum maximum Jacq in a dairy farm in the Peruvian tropics. The forage variables were growth rate and forage availability and the animal variables were the chemical composition of the diet and feed profile. The experiment was carried out in the dry, early rainy and rainy seasons. Fourteen enclosures were installed in 41.9 ha and five Brown Swiss x Creole lactating cows were used. Forage growth and availability rates were obtained through cutting and manual separation, diets were obtained by manual simulation, energy requirement through the budget of activities and feed profile through the balance of forage demand and supply. A completely randomized design was used for forage growth and availability, and random blocks for chemical composition. The forage growth rate ...

Moderate resolution imagery (MODIS) data from the Normalized Difference Vegetation Index (NDVI) can be used to estimate aboveground biomass at large spatial scales; however, validation of the information with fieldwork is required to make more accurate grassland vegetation predictions. The study was conducted in three districts of the central highlands of Peru. In total, 153 grass samples (high grassland and low grassland) were collected after reading NDVI in situ within a pixel of 250x250 m, with a frequency of three months during a three year period. Satellite images were downloaded from the MODIS sensor to obtain the NDVI. The NDVI-MODIS values were calibrated with the NDVI registered in situ, using regression models. The calibrated equations modelled the dynamic trends of vegetation between 2000 and 2018 for the central highlands. The NDVI in situ of the low grassland ranged between ...

Variables inherent to the forage and animal component were evaluated to design feed profiles of dual-purpose cows grazing Panicum maximum Jacq in a dairy farm in the Peruvian tropics. The forage variables were growth rate and forage availability and the animal variables were the chemical composition of the diet and feed profile. The experiment was carried out in the dry, early rainy and rainy seasons. Fourteen enclosures were installed in 41.9 ha and five Brown Swiss x Creole lactating cows were used. Forage growth and availability rates were obtained through cutting and manual separation, diets were obtained by manual simulation, energy requirement through the budget of activities and feed profile through the balance of forage demand and supply. A completely randomized design was used for forage growth and availability, and random blocks for chemical composition. The forage growth rate ...

Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en Producción Animal

Universidad Nacional Agraria La Molina. Escuela de Posgrado. Doctorado en Ciencia Animal

The aim of this study was to compare the expected genetic progress of the selection indexes for Corriedale sheep based on performance and progeny tests. The study was carried out in the “Corpacancha” Production Unit of the SAIS Pachacútec, Junín, Peru, at an altitude of 4150 meters above sea level. A performance test was used based on bodyweight and fleece weight, and the mixed model to obtain the best unbiased linear predictor (BLUP), where the fixed effects were sex, type of parturition and a covariate age at weaning. The progeny was 118 females and 73 males. The bodyweight at first shearing was 65.86 ± 13.25 kg and the clean fleece weight of 5.99 ± 1.44 kg. The fertility rate was 75%, birth rate 109.7%, twin births 4.8% and 1.7 services/pregnancy. The bodyweight correlation with fleece weight was 0.47, suitable for the selection indices. The expected genetic progress of the pe...

The aim of this study was to compare the expected genetic progress of the selection indexes for Corriedale sheep based on performance and progeny tests. The study was carried out in the “Corpacancha” Production Unit of the SAIS Pachacútec, Junín, Peru, at an altitude of 4150 meters above sea level. A performance test was used based on bodyweight and fleece weight, and the mixed model to obtain the best unbiased linear predictor (BLUP), where the fixed effects were sex, type of parturition and a covariate age at weaning. The progeny was 118 females and 73 males. The bodyweight at first shearing was 65.86 ± 13.25 kg and the clean fleece weight of 5.99 ± 1.44 kg. The fertility rate was 75%, birth rate 109.7%, twin births 4.8% and 1.7 services/pregnancy. The bodyweight correlation with fleece weight was 0.47, suitable for the selection indices. The expected genetic progress of the pe...

Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en Producción Animal

The aim of this study was to compare the effect of N, P and K fertilization on the production of aerial biomass of two native grasses Festuca dolichophylla and Festuca humilior. The experiment was carried out in the SAIS Túpac Amaru, Junín, Peru, at an altitude of 4186 m. The treatments were N, P, K, NPK and a control. The nitrogen, phosphorus and potassium doses were 36.24, 4.27 and 29.92 kg/ha, respectively. The model of blocks with orthogonal contrasts was used. The variables were: fresh aerial biomass (kg/ha), dry aerial biomass (kg/ha) and percentage of dry matter. Fresh aerial biomass was 783.9±110.7 and 662.9±24.9 kg/ha, dry aerial biomass was 477.6±62.9 and 410.2±15.4 kg/ha, and percentage of dry matter was 64.11±1.82 and 61.47±0.56% in F. dolichophylla and F. humilior, respectively, with F. dolichophylla being the species with the highest production of aerial biomass (p&...

The aim of this study was to compare the effect of N, P and K fertilization on the production of aerial biomass of two native grasses Festuca dolichophylla and Festuca humilior. The experiment was carried out in the SAIS Túpac Amaru, Junín, Peru, at an altitude of 4186 m. The treatments were N, P, K, NPK and a control. The nitrogen, phosphorus and potassium doses were 36.24, 4.27 and 29.92 kg/ha, respectively. The model of blocks with orthogonal contrasts was used. The variables were: fresh aerial biomass (kg/ha), dry aerial biomass (kg/ha) and percentage of dry matter. Fresh aerial biomass was 783.9±110.7 and 662.9±24.9 kg/ha, dry aerial biomass was 477.6±62.9 and 410.2±15.4 kg/ha, and percentage of dry matter was 64.11±1.82 and 61.47±0.56% in F. dolichophylla and F. humilior, respectively, with F. dolichophylla being the species with the highest production of aerial biomass (p&...

Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en Producción Animal

Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en Producción Animal

The aim of this study was to compare the growth, biomass accumulation, tillering dynamics and water behavior of Festuca dolichophylla (Presl, 1830) (fedo) and Festuca humilior (Nees y Meyen, 1841) (fehu). The study was carried out in grasslands of good condition in the Peruvian highlands at an altitude of 4186 m. The model included species and month as fixed effects, and age post-plating as a random effect. fedo evidenced a greater height to the flag leaf with 29.66±0.56 cm and volume of grass with 993.88±44.34 cm3, while fehu evidenced a greater proportion of flowering with 35.71±1.84%. Both species had a similar quantity of basal tillers. In March-2016 the highest peak of volumetric soil moisture (20 cm) with 57.37±0.78% was evidenced, while in September 2016 it was the lowest peak with 13.86±0.83%. In December 2016, the highest transpiration peaks were evident with 92-95 mmol m2-...

The aim of this study was to compare the growth, biomass accumulation, tillering dynamics and water behavior of Festuca dolichophylla (Presl, 1830) (fedo) and Festuca humilior (Nees y Meyen, 1841) (fehu). The study was carried out in grasslands of good condition in the Peruvian highlands at an altitude of 4186 m. The model included species and month as fixed effects, and age post-plating as a random effect. fedo evidenced a greater height to the flag leaf with 29.66±0.56 cm and volume of grass with 993.88±44.34 cm3, while fehu evidenced a greater proportion of flowering with 35.71±1.84%. Both species had a similar quantity of basal tillers. In March-2016 the highest peak of volumetric soil moisture (20 cm) with 57.37±0.78% was evidenced, while in September 2016 it was the lowest peak with 13.86±0.83%. In December 2016, the highest transpiration peaks were evident with 92-95 mmol m2-...

The models of growth and allometry of grasslands allow to know growth and development phenomena. Consequently, the aim of this study was to develop a multi-species allometric model to estimate biomass in three grasses in the High Andean Zone of Jauja, Peru, at an altitude of 3600 m above sea level. The native grasses were Festuca dolichophylla (J. Presl) tall (50-90 cm), Festuca humilior (Nees & Meyen) medium (20-35 cm) and Calamagrostis vicugnarum (Weddell) Pilger short (5- 25 cm). The measured variables were biomass (g, YB), basal diameter (cm, XD), canopy diameter (cm, XC) and height (cm, XH). The potential regression was used by choosing the strength of the models by the Akaike criterion (IAC) and the adjusted coefficient of determination (adjusted R2). The multispecies allometric model was Y = 1,238 * XD2,231, due to its lower IAC (383.795) and higher adjusted R2 (85.4%). C. vic...

The models of growth and allometry of grasslands allow to know growth and development phenomena. Consequently, the aim of this study was to develop a multi-species allometric model to estimate biomass in three grasses in the High Andean Zone of Jauja, Peru, at an altitude of 3600 m above sea level. The native grasses were Festuca dolichophylla (J. Presl) tall (50-90 cm), Festuca humilior (Nees & Meyen) medium (20-35 cm) and Calamagrostis vicugnarum (Weddell) Pilger short (5- 25 cm). The measured variables were biomass (g, YB), basal diameter (cm, XD), canopy diameter (cm, XC) and height (cm, XH). The potential regression was used by choosing the strength of the models by the Akaike criterion (IAC) and the adjusted coefficient of determination (adjusted R2). The multispecies allometric model was Y = 1,238 * XD2,231, due to its lower IAC (383.795) and higher adjusted R2 (85.4%). C. vic...

The aim of this study was to determine the growth rate and nutritional quality of Guinea grass (Panicum maximum Jacq) under a silvopastoral system with the faique tree (Acacia macracantha). The evaluation included two seasons (rainy and dry) and three treatments: (1) under the canopy of the young tree, (2) under the canopy of the medium-size tree, and (3) outside the canopy of the tree. The trees were classified according to the diameter at chest height. The growth and quality of the grass were measured by the method of cutting and separation and subsequent laboratory analysis. The growth rate ranged from 71.09 to 51.15 kg DM/ha/d, outside and inside the tree canopy, respectively, in the rainy season. Crude protein varied from 10.58, 12.79 and 13.88% (rainy season) and 8.93, 10.26 and 11.99% (dry season) outside the tree canopy, under the young tree canopy and under the middle tree canop...

The aim of this study was to determine the growth rate and nutritional quality of Guinea grass (Panicum maximum Jacq) under a silvopastoral system with the faique tree (Acacia macracantha). The evaluation included two seasons (rainy and dry) and three treatments: (1) under the canopy of the young tree, (2) under the canopy of the medium-size tree, and (3) outside the canopy of the tree. The trees were classified according to the diameter at chest height. The growth and quality of the grass were measured by the method of cutting and separation and subsequent laboratory analysis. The growth rate ranged from 71.09 to 51.15 kg DM/ha/d, outside and inside the tree canopy, respectively, in the rainy season. Crude protein varied from 10.58, 12.79 and 13.88% (rainy season) and 8.93, 10.26 and 11.99% (dry season) outside the tree canopy, under the young tree canopy and under the middle tree canop...

The aim of this study was to determine the effect of two ages of the long-spine acacia tree (Acacia macracantha) on the physical and chemical characteristics of the soil in a silvopastoral system with Guinea grass (Panicum maximum Jacq). The study was conducted in the Bellavista district, Cajamarca, Peru. The mechanical resistance, apparent density, humidity and temperature of the soil, as well as the content of organic matter, phosphorus (P2O5) and potassium (K2O) were evaluated in three soil locations: under the canopy of young (BCAj) and medium trees (BCAm) and outside the tree canopy (FCA), in two seasons of the year (dry and rainy). A complete randomized design with factorial arrangement 3 (location) x 2 (seasons) was used. Under the canopy of the medium trees, a lower soil temperature (27.96 °C) and higher soil humidity (15.23%) were found, in addition to improving soil fertility....

The aim of this study was to determine the effect of the age of the quail (Coturnix coturnix japonica) on the morphometry of the egg and the size of the bird at birth. In total, 227 fertile quail eggs of three ages (15, 19 and 34 weeks) were used. Egg weight (g), shape index (%), hatching weight (g), body weight/egg weight ratio, and hatching length (mm) were evaluated using a completely randomized block design. There were no significant differences between ages with egg weight. Egg shape index was significantly higher in 15-week-old birds (79.50±0.34%) than in 34-week-old birds (78.0±0.36%; p<0.05). Birth weight was greater for 34-week-old birds (7.91±0.08 g) compared to 15-week-old birds (7.63±0.07 g; p<0.05). Live weight/egg weight ratio was significantly different between breeders of 15 (68.9±0.37%) and 34 weeks (70.4±0.41%), while quail length at hatch was greater in 19-...