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Natural And Artificial Drying Effects On Condensed Tannins Of Sericea Lespedeza, T H. University Of Georgia, W R. Windham, J J. Evans, C S. Hoveland May 2025

Natural And Artificial Drying Effects On Condensed Tannins Of Sericea Lespedeza, T H. University Of Georgia, W R. Windham, J J. Evans, C S. Hoveland

IGC Proceedings (1977-2023)

Sericea lespedeza [Lespedeza cuneata (Dumont-Cours.) G. Don.] is well adapted to acid soils and low fertility but has generally been considered a low-quality forage due to high levels of tannin and indigestible fiber. Tannin levels increase during midsummer (Windham et al. 1988). The most com­monly used assay for tannin in sericea is the vanillin-HCl pro­cedure (Burns, 1963) on oven-dried samples. Oven-drying has been reported to cause increased polymerization or oxidative changes in tannins (Goldstein and Swain, 1963). Fresh-frozen sericea contained higher amounts of extract­able tannin than field-dried forage and fiber digestibility of high-tannin sericea by sheep was much lower …


Ediacaran Paleocommunity Structure, Body Size Evolution, And The Rise Of Complex Animals, Matthew Philip Craffey May 2025

Ediacaran Paleocommunity Structure, Body Size Evolution, And The Rise Of Complex Animals, Matthew Philip Craffey

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The Ediacaran period (635-538ma) is a key interval in the evolution of life as it records the first macroscopic animal communities. Major extinction pulses appear to have altered the composition of the global marine biosphere between each sub-interval of the Ediacaran Period: the Avalon, White Sea, and Nama assemblage Zones. While considerable attention has been paid to the causes of these extinction pulses, less has been afforded to the consequences of Ediacaran biotic turnover for community organization and function. Moreover, it is unclear how body size - the defining trait of macrofauna - affected the transition between animal groups across …


Maggot Mass Effect On The Development And Survival Of Forensic Blow Flies, Akomavo Fabrice Gbenonsi May 2025

Maggot Mass Effect On The Development And Survival Of Forensic Blow Flies, Akomavo Fabrice Gbenonsi

School of Natural Resources: Dissertations, Theses, and Student Research

Forensic entomology scientists use blow flies' developing patterns to estimate the postmortem interval (PMI). However, larval aggregations produce metabolic heat, resulting in complex microclimates that may change growth timetables. This study investigates how larval density and associated temperature changes affect the development and survival of two forensically essential blow fly species, Lucilia sericata and Calliphora vicina.

This study examined how larval density and associated thermal profiles affect the development of both blow fly species. Using a split-plot design, we tested four larval densities at 25°C and 30°C, with temperature gradients measured via thermocouple at four mass positions three times …


Assessment Of Sampling Gears For Bigheaded Carp In Mid-Order Prairie Rivers In Nebraska, Brett M. Anderson May 2025

Assessment Of Sampling Gears For Bigheaded Carp In Mid-Order Prairie Rivers In Nebraska, Brett M. Anderson

School of Natural Resources: Dissertations, Theses, and Student Research

Silver Carp Hypophthalmichthys molitrix and Bighead Carp H. nobilis (collectively bigheaded carp) have invaded tributaries to the Missouri River and Platte River in Nebraska, USA. Information pertaining to efficient sampling protocols for assessing bigheaded carp populations as well as benefiting removal efforts is needed. Herding is a method used to increase the capture efficiency and detection probability of adult bigheaded carp by simultaneously using active and passive sampling gears. During June-July 2023, four herding techniques were assessed regarding their ability to elicit directional movement past an enclosure gate. The combination of sound and electrofishing resulted in the highest mean …


Improved Snow Distribution Estimates Using A Rapid-Response Lidar And Photogrammetry System, Naheem Idowu Adebisi May 2025

Improved Snow Distribution Estimates Using A Rapid-Response Lidar And Photogrammetry System, Naheem Idowu Adebisi

Boise State University Theses and Dissertations

Snow plays a critical role in global hydrology, climate systems, and human activities, particularly in mountainous regions where it is a primary source of freshwater, influences the energy balance, and impacts mobility and commerce. Despite its importance, accurately mapping and predicting snow distribution remains a major challenge due to the complex spatial and temporal variability of snowpack and the lack of an ideal observation system. This dissertation aims to advance our monitoring capability, understanding, and prediction capacity of snow distribution using Light Detection and Ranging (LiDAR) and photogrammetry techniques.

In chapter 2, I discussed the high-resolution LiDAR-derived datasets of multiple …


Effects Of Environmentally Relevant Concentrations Of Roundup On Oxidative-Nitrative Stress, Cellular Apoptosis, Prooxidant-Antioxidant Homeostasis, Renin And Cyp1a Expressions In Goldfish: Molecular Mechanisms Underlying Kidney Damage During Roundup Exposure, Md Imran Noor, Md Saydur Rahman May 2025

Effects Of Environmentally Relevant Concentrations Of Roundup On Oxidative-Nitrative Stress, Cellular Apoptosis, Prooxidant-Antioxidant Homeostasis, Renin And Cyp1a Expressions In Goldfish: Molecular Mechanisms Underlying Kidney Damage During Roundup Exposure, Md Imran Noor, Md Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Roundup is one of the most widely used glyphosate-based harmful herbicides in the United States as well as globally, which poses a severe risk for terrestrial and aquatic organisms. In order to identify the detrimental effects of Roundup exposure in aquatic organisms, we investigated the environmentally relevant concentrations of Roundup exposure (low dose: 0.5 μg/L and high dose: 5.0 μg/L for 2 weeks) on renin expression, oxidative-nitrative stress biomarkers (e.g., 2,4-dinitrophenol, DNP; and 3-nitrotyrosine protein, NTP), prooxidant-antioxidant enzymes expressions (e.g., superoxide dismutase, SOD; and catalase, CAT), cellular apoptosis, and cytochrome P450 1A (CYP1A) mRNA levels in the kidneys of goldfish …


Microplastics In Coastal And Marine Environments: A Critical Issue Of Plastic Pollution On Marine Organisms, Seafood Contaminations, And Human Health Implications, Rebecca Muñiz, Md. Saydur Rahman May 2025

Microplastics In Coastal And Marine Environments: A Critical Issue Of Plastic Pollution On Marine Organisms, Seafood Contaminations, And Human Health Implications, Rebecca Muñiz, Md. Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Plastic has quickly become one of the world's most prevalent environmental pollutants. Population growth has only amplified the demand, resulting in 430 million tons of plastic produced annually, with 11 million tons ending up in our oceans. Without intentional intervention, plastic waste in the oceans is expected to triple, posing severe risks for the aquatic ecosystems, animals, and humans dependent on these waters. As plastic accumulates in oceans and other water environments, the non-biodegradable particles break down into micro- and nano-plastics, invading coastal and marine organisms and causing considerable physiological and morphological damage. This is especially concerning for the millions …


Spatio-Temporal Pattern Of Nutrient Dynamics In The South Texas Coastal Watershed, Mohammad Sadman Alam May 2025

Spatio-Temporal Pattern Of Nutrient Dynamics In The South Texas Coastal Watershed, Mohammad Sadman Alam

Theses and Dissertations

Eutrophication threatens aquatic ecosystems by altering productivity through excessive nutrient inputs. In some systems, primary productivity is limited by nitrogen (N), phosphorus (P), or both, based on the N:P ratio defined by the "Redfield" ratio. South Texas, facing rapid urban growth and industrialization, is at risk of higher nutrient loads, but research on nutrient dynamics in this region is limited. This study investigates nutrient variations in the freshwater (FW) abandoned distributaries of the Rio Grande and hypersaline saltwater (SW) systems. Results showed a significant decrease in dissolved inorganic nitrogen (DIN) and an increase in dissolved inorganic phosphorus (DIP), shifting the …


Inferring Feeding Biology In Extinct Shrews (Soricidae: Mammalia): Application Of A Linear Morphometric Approach, Derek J. Den Ouden May 2025

Inferring Feeding Biology In Extinct Shrews (Soricidae: Mammalia): Application Of A Linear Morphometric Approach, Derek J. Den Ouden

Electronic Theses and Dissertations

Linear morphometrics have been used extensively to infer the ecology of fossil organisms, but shrews have not yet been thoroughly explored using this technique. Often considered to have a homogenous insectivorous diet, direct dietary observation suggests shrew dietary diversity is substantial. Diversity of this nature is well established to have influenced skull morphology in other mammal clades, so similar patterns are hypothesized to be detectable in shrews. To test this, I examined the link between known diet and morphological disparity in extant shrews using linear morphometrics and then utilized that framework to infer the dietary ecology of several fossil taxa. …


Cranial Ontogeny Of The Extinct Dwarf Tapir Tapirus Polkensis; With Comparison To That Of The Extant Tapirus Bairdii (Tapiridae, Perissodactyla), Johannah Orendorff May 2025

Cranial Ontogeny Of The Extinct Dwarf Tapir Tapirus Polkensis; With Comparison To That Of The Extant Tapirus Bairdii (Tapiridae, Perissodactyla), Johannah Orendorff

Electronic Theses and Dissertations

Tapirus polkensis is the smallest known species of tapir to ever live, and the largest deposit of their fossils is currently located at the GFS in Gray, TN. Phylogenetics suggest that the extant T. bairdii may be the sister taxon to T. polkensis, although they differ greatly in their morphology. Variation exists among adult T. polkensis specimens, with patterns not present in T. bairdii. For this study, as series of 2D GMAs, with TPSs, were rendered on 10 skulls of T. polkensis and 48 skulls of T. bairdii, across both species’ ontogenetic series. Analyses confirmed that growth …


A System And Method For Measuring Spatially Varying Surface Appearances With A Study Of Feathers, Jessica Baron-Lis May 2025

A System And Method For Measuring Spatially Varying Surface Appearances With A Study Of Feathers, Jessica Baron-Lis

All Dissertations

Real-world materials, particularly biological structures such as feathers exhibit complex appearances that vary spatially across their surfaces. The field of computer graphics provides a means of understanding such surfaces through material modeling which uses both analytical models and data acquired from light-surface interactions. There are many efforts within the past decade in measuring materials for graphics, but common limitations in these works include not accounting for spatially varying properties and reliance on neural networks and synthetic datasets.

Feathers from modern birds present diverse appearances due to how light interacts with their unique hierarchical microstructures. Variations in those structures lead to …


Development Of Isoscapes For Hong Kong Freshwater Streams As A Basis For Ecological Studies, Hon Tim Yip Apr 2025

Development Of Isoscapes For Hong Kong Freshwater Streams As A Basis For Ecological Studies, Hon Tim Yip

Lingnan Theses (MPhil & PhD)

Applications of isoscapes in terrestrial and marine ecosystems have grown notably as a tool for studying animal movement. However, isoscapes are rarely used in freshwater ecosystem because current iterations of isoscapes commonly model baseline distributions of bulk stable isotope analysis (SIA) data, which may be inadequate for providing the necessary resolution for fine spatial scale stream environments. This issue could potentially be addressed using compound specific stable isotope analysis, a new method that measures the isotopic composition of individual compounds to provide more comprehensive information than bulk SIA. My study focuses on δ13C of essential amino acids (EAA-δ …


Grassland For Our World, F Riveros Apr 2025

Grassland For Our World, F Riveros

IGC Proceedings (1977-2023)

The present-day role of grasslands and fodder is reviewed with respect agriculture, animal production and environmental concerns. The world 's grazing lands are a finite resource nnd, overall, are being badly mnnaEed; in most developing countries action is required now, before it is too lnte. They will continue to be a major source of animal feed for the foreseeable future; encroachment from cropping will con


Effect Of Irrigation On Vegetation Succession And Forage Regerneration, Fu Jing-Yan Apr 2025

Effect Of Irrigation On Vegetation Succession And Forage Regerneration, Fu Jing-Yan

IGC Proceedings (1977-2023)

No abstract provided.


On The Cultivation And Utilization Of Floret Silvergrass (Miscanthus Floridulus) In The Southern Area Of China, Zhu Bangchang Apr 2025

On The Cultivation And Utilization Of Floret Silvergrass (Miscanthus Floridulus) In The Southern Area Of China, Zhu Bangchang

IGC Proceedings (1977-2023)

The plant genus Miscanthus (silvergrass) includes eight species and one variety in China. In the tropical and subtropi­cal area of south China, the silvergrass distributed widely includes the following seven species : Floret silvergrass ( Miscanthus floridulus), Chinese silvergrass ( M. sinensis), Sugary silvergrass ( M. sacchariflorus), Short-hair silvergrass ( M. brevipilus j, Eulalia silver grass ( M. eulalioides), Szechuan silvcrgrass ( M. szechuanensis), Nepal silvergrass ( M. nepalen�� sis). One of them, Floret silvergrass, is the widest in distri­bution and the highest in economical value, and plays a most important role in …


Herbage Dynamics And Plant-Animal Performance On Altered Northern Great Plains Rangelands, P O. Currie, D C. Adams, J D. Volesky Apr 2025

Herbage Dynamics And Plant-Animal Performance On Altered Northern Great Plains Rangelands, P O. Currie, D C. Adams, J D. Volesky

IGC Proceedings (1977-2023)

Mechanical, chemical, and seeding treatments have been used on rangeland to increase herbage production (Griffith et al., 1985). These treatments are generally applied to rangelands in a low serial stage of succession. Improving these rangelands is of major economic importance to livestock producers attempting lo increase the efficiency of their operations. Our study evaluated 5 range improvement treatments for improving herbage and ani­mal production efficiency


Methodology To Determine Planting Time In King Grass (Pennisetum Sp.) Using Historical Climatic Indices, J R. Ayala, M Sistachs, R S. Herrera Apr 2025

Methodology To Determine Planting Time In King Grass (Pennisetum Sp.) Using Historical Climatic Indices, J R. Ayala, M Sistachs, R S. Herrera

IGC Proceedings (1977-2023)

The determination of planting time by field trials has various disadvantages. These trials should be repeated at least for 3 years comparing different months and the extension of the results is limited. The analysis of the climatic effects would allow a greater generalization with correlations between cli­matic and establishment indices. The season of the year in which the highest number of correlations with monthly histori­cal climatic values are fulfilled is required so as to determine planting time. The objective of the present methodology is to select planting time by using correlations between climatic and establishment indices and the monthly characterization …


Methods For The Establishment Of Leucaena Leucocoephala In Cuba, T E. Ruiz, G Febles, N Sistachs, L E. Diaz, G Bernal, J J. Leon Apr 2025

Methods For The Establishment Of Leucaena Leucocoephala In Cuba, T E. Ruiz, G Febles, N Sistachs, L E. Diaz, G Bernal, J J. Leon

IGC Proceedings (1977-2023)

Studies in tropical and sub-tropical regions of the world on the factors influencing the establishment and early manage­ment of legume swards as pure cultures have not been carried out integrally. Thus, the objective of the present study was to define the best options of the main components so as to develop a technology for establishing Leucaena leucocephala under our conditions.


Studies On Seed Storage And Sowing Time Of Leucaena Leucocphala In Cuba, T E. Ruiz, G Febles Apr 2025

Studies On Seed Storage And Sowing Time Of Leucaena Leucocphala In Cuba, T E. Ruiz, G Febles

IGC Proceedings (1977-2023)

Germination of stored seeds and sowing time are essential factors that must be known when a technology for pasture utili­zation is required (Febles and Ruiz, 1986; Ruiz and Febles, 1986). Thus, these experiments were set out to learn the per­formance of the seed quality of Leucaena leucocephala cv Peru stored under different conditions and to determine the influence of the sowing time of this species during the rainy season.


Factors Influencing Pasture Establishment And Persistence In The Mid-Altitude Zone, Yunnan, Southern China, Kui Jia-Xiang, R N. Glencross, Ai Hongxin, Chen Xiong Apr 2025

Factors Influencing Pasture Establishment And Persistence In The Mid-Altitude Zone, Yunnan, Southern China, Kui Jia-Xiang, R N. Glencross, Ai Hongxin, Chen Xiong

IGC Proceedings (1977-2023)

The mid-altitude zone in Yunnan Province of SW China ranges from 1500-2500 m in altitude and has a climate inter­grading between sub-tropical and temperate with a mean temp. of 7-10°C in the coldest month and 19-22 °C in the hottest month. The annual rainfall ranges from 800-1200 mm with 80 % falling in the monsoon period, May to September. About 80 % of the total 39.4 m ha of the province is in this very hilly mid-altitude zone. (He et al., 1982) Native grassland vegetation is dominated by Themeda trianda, Arundinella radoli, Imperata cylindrica and some other grasses such as …


Obtention Of King Grass (Pennisetum Purpureum) Clones From Tissue Culture. Selection And Evaluation Of Mutants, R O. Martinez, M Monzote, R S. Herraera, R Cruz, V Torres Apr 2025

Obtention Of King Grass (Pennisetum Purpureum) Clones From Tissue Culture. Selection And Evaluation Of Mutants, R O. Martinez, M Monzote, R S. Herraera, R Cruz, V Torres

IGC Proceedings (1977-2023)

King grass (2n = 28) is widely used in Cuba for forage pro­duction. The increase in the variability of this species is there­fore of special interest in agriculture. Tissue culture as a tech­nique to produce and select somaclones from the king grass donor was used to obtain variability. These were obtained when the apical meristems were cultivated in MS medium with 3 mg/I of 2,4 D to regenerate the plants with different hormonal combinations. Those of 0.1 mg/! of kinetine (Martinez, 1986) were prominent. The variability in the selection and evaluation processes is exposed in this paper.


The Efficacy Of A High Magnesium Italian Ryegrass Cultivar In Alleviating Hypomagnesamia, G Moseley, D M. Baker, D H. Hides Apr 2025

The Efficacy Of A High Magnesium Italian Ryegrass Cultivar In Alleviating Hypomagnesamia, G Moseley, D M. Baker, D H. Hides

IGC Proceedings (1977-2023)

Hypomagnesaemia continues to cause serious economic losses in grazing livestock and recent evidence suggests that its incidence may be increasing. The disease is characterised by a drop in the concentration of magnesium in extracellular fluid and occurs in two forms, chronic and acute. Both forms give rise to classical clinical symptoms which may either result in death or drastically reduced levels of production. The body does not contain a major source of labile magnesium nor does it have a homeostatic mechanism for controlling the level of magnesium in extracellular fluid. The maintainance of normal levels therefore depends almost entirely on …


Evaluation And Selection Of The Salt-Tolerant Alfalfa, Geng Huazhu Apr 2025

Evaluation And Selection Of The Salt-Tolerant Alfalfa, Geng Huazhu

IGC Proceedings (1977-2023)

Alfalfa (Medicago sativa) as a good forage has b��en popu­larly cultivated for a long time in China. Now it is mainly distributed in the north of the Yangtse River, and covers about 1.3 million hectares in the 14 provinces and regions. It can be planted in the saline-alkali areas, accept alluvial plains and hill regions, for instance, the North of Jiangsu, East of Hebei, North-west of Shandong and Xingjiang. The alfalfa is success­fully used in improving and utilizing the saline-alkali soils for developing animal husbandry in the Gangzhou District of Hebei Province, where its planting area is increasing rapidly, …


Plant Improvement Using Endophytic Fungi, G C.M Latch Apr 2025

Plant Improvement Using Endophytic Fungi, G C.M Latch

IGC Proceedings (1977-2023)

Endophytic fungi which grow intercellularly in many species of grasses have been a scientific curiosity for almost a century. The mycelium of many of these fungi never emerges from the plant and the fungus is disseminated by way of hyphae in the seed. Other endophytes such as Epichloe typhina form a myce­lial weft around the developing inflorescences thus preventing seed formation. Grasses infected with endophytes usually appear healthy and the presence of the fungus can only be detected by examining tissues from leaf, sheath, culms and seed for fungal mycelium. The economic importance of these fungi was first discovered by …


Non Conventional Evaluation Of Tropical Pasture Accessions, R T. Paterson Apr 2025

Non Conventional Evaluation Of Tropical Pasture Accessions, R T. Paterson

IGC Proceedings (1977-2023)

Many thousands of tropical and sub-tropical grass and legume accessions are to be found in germplasm banks in Australia (Tropical Forages Genetic Resources Centre), Colombia (CIAT), Ethiopia (ILCA) and other countries, but most are poorly categorized in terms of their climatic, edaphic and biotic adaptation. In contrast, a number of ecosystems in the developing world are poorly served with pasture varieties capable of sustaining high levels of animal production. It is likely that such material exists in germplasm collections, but since it has not been tested under a range of conditions, it remains unidentified. There is an urgent need to …


Research On Distant Hybridization Between Melissutus Ruthenicus C.W Chang And Medicago Sativa Zhaodong, Wang Diankui, Li Hong, Luo Xinyi Apr 2025

Research On Distant Hybridization Between Melissutus Ruthenicus C.W Chang And Medicago Sativa Zhaodong, Wang Diankui, Li Hong, Luo Xinyi

IGC Proceedings (1977-2023)

Distant hybridization can be used to combine the characteri­stics of different species and genus to produce a new variety. By crossing the wild species Melissutus ruthenicus C.W. Chang (2n = 2x = 16) which exhibits cold-, drought- and salt-alkali resistance with the local high-yielding cultivar Medicago saliva Zhaodong (2 n = 4 x = 32), it was hoped to synthesize the fine characteristics of two parents, to obtain a new intermediate variety of alfalfa. This paper reports on the advance of the hyb­ridization, the results of cytological studies and the tendency of variations of filial generations as a guide to …


Breeding Guinea Grass (Panicum Maximum Jacq.) For Stall-Feeding, B S. Sidhu, P D. Mehndiratta, R K. Batta Apr 2025

Breeding Guinea Grass (Panicum Maximum Jacq.) For Stall-Feeding, B S. Sidhu, P D. Mehndiratta, R K. Batta

IGC Proceedings (1977-2023)

Punjab is a part oflndo-Gangetic plain with sub-tropical cli­mate. Due to fertile alluvial soil, assured irrigation and small holdings intensive agriculture is in practice. Same plain land is suitable for forage as well as grain production, thus farmers sel­ect to grow which is profitable. Production of milk by stall­feeding of animals on multicut annual summer grasses raised under heavy nitrogen and assured irrigation is relatively econ­omical for the farmers. Thus, a breeding programme on Guinea Grass which responds better to nitrogen than many other summer grasses, was undertaken to develop fast growing annual type which may be cultivated to produce …


Great Diversity For Increased Yield Within Narrow Grass Population, Glenn W. Burton Apr 2025

Great Diversity For Increased Yield Within Narrow Grass Population, Glenn W. Burton

IGC Proceedings (1977-2023)

Increasing yield of animal product per unit of input is the ultimate objective of any forage breeding project. It increases the efficiency of production and the profit of the producer. It may be achieved by screening and utilizing the world diversity of a species as has been demonstrated in Cynodon spp. (Burton, 1947, 1988). It can also be realized by recurrent restricted phenotypic selection (RRPS) within a narrow-based grass pop­ulation. Pensacola bahiagrass, Paspalum notatum var. saure Parodi, a sexual diploid (2n = 20) that occupies several million hectares in the southern USA is such a grass. It originated as a …


The Study On The High Yield Property Of Billion Dollar Grass, Wan Lishong, Liu Shenglin, Geng Renren, Shao Shengrong, Jiang Wenkui Apr 2025

The Study On The High Yield Property Of Billion Dollar Grass, Wan Lishong, Liu Shenglin, Geng Renren, Shao Shengrong, Jiang Wenkui

IGC Proceedings (1977-2023)

In 1964, one plant of billion dollar grass (Echinochloa crus­galli Link) was found by Wan Lisheng in artificial grassland in mid-part of the desert steppe in Ningxia, China. 50 g of seeds were collected in the same year. After 24 years' systematic selec­tion breeding, a new variety named Hai zi-1 billion dollar grass (BDG) was developed. The characteristics of the grass were high-yield and fine quality with extraordinary plant height. The average height of the community was 180-230 cm, the highest plant could be 250 cm high. Its field yield was 16,866 t/ha DM in Ningxia plain irrigated area …


Grass Adaptation In Cuba. Ii. Regional Results With New Cultivars, J J. Paretas Apr 2025

Grass Adaptation In Cuba. Ii. Regional Results With New Cultivars, J J. Paretas

IGC Proceedings (1977-2023)

In Cuba, bovine feeding is based on the maximum pasture and forage utilization. Pastures occupy approximately 3.0 mil­lion hectares, the highest agricultural area of the country. From there, one million hectares are sown with improved varieties and the rest with low yielding and poor quality natural species or shrub areas with a very poor utilization area (Paretas and Carballar, 1988). On considering the high genetic potential of the animals mainly pures or with a high Holstein blood percentage, empha­sis is made to transform the areas dedicated to pasture by improving the varieties yielding more and with a more stable production …