Jaime Nieto

Dr. Jaime Nieto

University of Salamanca, Salamanca, Castille-Leon, Spain
orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
25 January 2022 in Journal of Animal Behaviour and Biometeorology
Verified
Journal Article
Open access
Javier PlazaJavier Plaza
Javier Plaza
NSNilda Sanchez
Nilda Sanchez
Carlos PalaciosCarlos Palacios
Carlos Palacios
MSMario Sánchez-García
Mario Sánchez-García
JAJosé Alfonso Abecia
José Alfonso Abecia
JNJaime Nieto
Jaime Nieto
Traditional knowledge about the behavior of grazing livestock is about to disappear. Shepherds well know that sheep behavior follows non-random patterns. As a novel alternative to seeking behavioral patterns, this study quantified the grazing activities of two sheep flocks of Churra breed (both in the same area but separated by 10 years) based on Global Position System (GPS) monitoring and remote monitoring sensing techniques. In the first monitoring period (2009-10), geolocations were recorded every 5 min (4,240 records), while in the second one (2018-20), records were taken every 30 min (7,636 records). The data were clustered based on the day/night and the activity (resting, moving, or grazing). An airborne LiDAR dataset was used to study the slope, aspect, and vegetation height. Four visible-infrared orthophotographs were mosaicked and classified to obtain the land use/land cover (LU/LC) map. Then, GPS locations were overlain on the terrain features, and a Chi-square test evaluated the relationships between locations and terrain features. Three spatial statistics (directional distribution, Kernel density, and Hot Spot analysis) were also calculated. Results in both monitoring periods suggested that the spatial distribution of free-grazing ewes was non-random. The flocks showed strong preferences for grazing areas with gentle north-facing slopes, where the herbaceous layer formed by pasture predominates. The geostatistical analyses of the sheep locations corroborated those preferences. Geotechnologies have emerged as a potent tool to demonstrate the influence of environmental and terrain attributes on the non-random spatial behavior of grazing sheep.

12 March 2022 in Veterinary Sciences
Verified
Journal Article
Open access
PDF file
JNJaime Nieto
Jaime Nieto
Javier PlazaJavier Plaza
Javier Plaza
JLJavier Lara
Javier Lara
JAJosé Alfonso Abecia
José Alfonso Abecia
IRIsabel Revilla
Isabel Revilla
Carlos PalaciosCarlos Palacios
Carlos Palacios
Insect larval meal is an increasingly common protein source in poultry systems. In this study, the effect of replacing soybean meal with Tenebrio molitor larval meal on the performance of slow-growing chickens was assessed. A total of 128 one-day-old chickens (Colorield) were randomly divided into a control group (C) (n = 64), fed with soybean meal, and an experimental group (TM) (n = 64), fed with T. molitor larvae meal. The chicks were slaughtered after 95 days. Three different isoenergetic and isoproteic diets (F1, F2 and F3) were used for each group. The F1 diet resulted in higher body weight gain and higher feed and water intakes in group C, but a lower feed conversion ratio. Contrarily, diets F2 and F3 did not produce differences in the studied parameters between the two groups, except for body weight gain in the case of diet F2, which was highest in group C. Therefore, weight gain and feed and water intakes were significantly higher in group C, but there were no differences in feed conversion ratio or live weight. In conclusion, the total replacement of soybean meal with T. molitor larvae meal resulted in a reduction in feed intake and a consequent reduction in weight. During this period, partial rather than total substitution may be recommended.

16 January 2023 in Poultry Science
Verified
Journal Article
Open access
JNJaime Nieto
Jaime Nieto
Javier PlazaJavier Plaza
Javier Plaza
JLJavier Lara
Javier Lara
JAJosé Alfonso Abecia
José Alfonso Abecia
IRIsabel Revilla
Isabel Revilla
CPCarlos Palacios
Carlos Palacios
Sustainable poultry meat production involves the use of slow-growing chick strains and the utilization of new protein sources as an alternative to the current monopoly of soybean meal. In this scenario, a study was conducted to assess the effect of replacing soybean meal with domestic cricket (Acheta domesticus) meal on the developing cycle of slow-growing chicks. To this end, a total of 128 one-day-old male chicks (Colorield) were randomly assigned into 16 experimental units, each consisting of 8 chicks, which in turn were grouped into 2 groups fed isoproteic and isoenergetic diets in which the protein source differed: the control group (C) fed soybean meal and the Acheta group (AD) fed Acheta domesticus insect meal as the main protein source. Chicks were slaughtered at 95 d of age. Three different diets (F1, F2 and F3) were used for each experimental group according to the nutritional needs of the birds during their growth. The F1 diet (1-29 d) resulted in higher feed and water intake and higher body weight gain for group C, but a lower feed conversion rate. On the contrary, during F2 (29-60 d) no differences in productive performances were observed between the 2 groups, except for a higher water intake for group C. Finally, during the period corresponding to diet F3 (60-95 d) there were only differences in feed intake, which was higher for the AD group. In conclusion, the substitution of soybean meal for Acheta domesticus meal caused a decrease in feed intake during the first month and consequently a lower body weight. During the first 4 weeks of life of the chicks, a partial replacement of soybean meal may be recommended, since high inclusions of A. domesticus meal in this period seem to be detrimental in young chicks. Given the absence of relevant differences in productive performances between both groups, it could be concluded that the use of A. domesticus cricket meal can be a potential protein alternative to soybean meal.

16 May 2021 in Animals
Verified
Journal Article
Open access
PDF file
Javier PlazaJavier Plaza
Javier Plaza
IRIsabel Revilla
Isabel Revilla
JNJaime Nieto
Jaime Nieto
Cristina Hidalgo-GonzálezCristina Hidalgo-González
Cristina Hidalgo-González
MSMario Sánchez-García
Mario Sánchez-García
Carlos PalaciosCarlos Palacios
Carlos Palacios
Currently, there are very few studies in the dairy sheep sector associating milk quality and indicators regarding carbon footprint and their link to grazing levels. For 1 year, monthly milk samples and records related to environmental emissions and management systems were collected through surveys from 17 dairy sheep farms in the region of Castilla y León (Spain), in order to relate this information to the use of natural pastures under free grazing. Indicators were constructed on the collected data and subjected to a multivariate statistical procedure that involved a factor analysis, a cluster analysis and a population canonical analysis. By applying multivariate statistical techniques on milk quality and carbon footprint indicators, it was possible to identify the management system of the farms. From an environmental point of view, farms with a higher grazing level (cluster 4) were more sustainable, as they had the lowest carbon footprint (lower CO2, N2O and CO2 equivalent emissions per sheep and year) and the lowest energy consumption levels, which were gradually lower than those of farms in cluster 3; both indicators were much lower than those of farms in clusters 1 and 2. The milk quality of cluster 1 and 2 farms was significantly lower in terms of total protein and fat content, dry extract, omega-3 fatty acid levels and α-tocopherol content than farms in clusters 3 and 4, which had higher accessibility to grazing resources. In sum, the higher the use of natural resources, the lower the external inputs the farms required and the lower environmental impact and energy costs they have.

6 February 2025 in Animals
Verified
Journal Article
Open access
PDF file
Manuel Gonzalez  RonquilloManuel Gonzalez Ronquillo
Manuel Gonzalez Ronquillo
Lizbeth Esmeralda Robles JimenezLizbeth Esmeralda Robles Jimenez
Lizbeth Esmeralda Robles Jimenez
JOJORGE OSORIO
JORGE OSORIO
IRIsabel Revilla
Isabel Revilla
Cristina Hidalgo-GonzálezCristina Hidalgo-González
Cristina Hidalgo-González
Carlos PalaciosCarlos Palacios
Carlos Palacios
It is necessary to study small-ruminant production systems in a spatial context, as different areas, depending on their natural, socioeconomic, and cultural context, will respond differently to the effects of such causal factors. The aim of this study was to analyze the relationships between technology use and farm and farmer characteristics in dairy sheep production by developing a farm typology using multivariate statistical analysis and comparing it with the multi-scale sustainability evaluation of the Natural Resource Management Systems (NRMS) method. Quantitative and qualitative data were evaluated and compared using the NRMS method and cluster analysis to identify groups of farms. Fourteen variables were considered for the analysis, resulting in four farm systems with the NRMS method, named Intensive, Semi-Intensive, Semi-Extensive, and Extensive; however, when analyzing the data by cluster analysis, the following clusters were used: Cluster 1, Semi-Extensive Dairy Systems (SEDSs); Cluster 2, Semi-Intensive Systems (SIDSs); Cluster 3, Semi-Extensive Cheese Systems (SECSs); and Cluster 4, Intensive Dairy Systems (IDSs). This study concludes that the traditional classification of dairy sheep farms based on their dependence on natural resources can be enriched by incorporating additional indicators that allow for a more comprehensive and accurate characterization of farms.

3 September 2024 in Journal of Applied Poultry Research
Verified
Journal Article
Open access
JAJosé Alfonso Abecia
José Alfonso Abecia
CPC. Palacios
C. Palacios
Javier PlazaJavier Plaza
Javier Plaza
JNJaime Nieto
Jaime Nieto
FCF. Canto
F. Canto