Universidad Nacional Agraria La Molina. Facultad de Zootecnia. Departamento Académico de Producción Animal

The aim of this research was to evaluate the effect of supplementation with two barley forage genotypes on milk production and quality in grazing cows. The genotypes evaluated were a local barley (Hordeum vulgare L.) and UNALM 96 M6h-326 barley in the district of Sincos, Junín (Peru). The experiment was conducted with 16 Brown Swiss - creole crossbred cows in second lactation and body weight of 385 ± 17 kg. Under a simple change design, the animals were divided into two groups for supplementation with 4 kg/day with one of the two barley forages. Supplementation was carried out in two stages of 13 days each, the first 8 days being for adaptation and the following 5 days for evaluation of milk production and composition. Milk production per cow/day was increased with UNALM 96 M6h-326 barley forage compared to the local variety (4.0 vs. 3.57 kg. p<0.05). Likewise, higher urea content i...

The objective of this study was to determine the enteric methane (CH4) emission factor (EF) at the national level for Peruvian dairy cattle following the IPCC Tier II (2006, 2019) methodology. Data were collected from seven regions of Peru and classified according to the type of feeding as intensive, semi-intensive or extensive. It included farm information (geolocation) and livestock information for two seasons of the year. At the national level, lactating cows obtained the highest EF with 117 kg CH4/head/year, followed by heifers from 15 to 24 months of age (91 kg), non-lactating cows (74 kg), heifers from 12 to 15 months of age (67 kg), calves (62 kg) and pre-weaned calves (16 kg). Additionally, the highest EF was reported for lactating cows in the intensive system (151.8 kg CH4/head), which is 46.8 kg CH4/head more per year than that reported in the semi-intensive and extensive syste...