Brazilian Tropical Grassland Ecosystems: Distribution and Research Advances

A few decades ago we sought the understanding of the functioning of Brazilian ecosystems. During these years, changes in the way land use were influenced primarily by economic issues involving the process of valuation of land in different regions. Furthermore, developments in research have provided productive increments that were well characterized in some phases. This paper aims to trace a brief history of the distribution of grassland ecosystems in Brazil and show how it has been the advances in research on forages and pastures in the country, pointing its evolution, transition times and trends. Moreover, it purports to show a perspective of the dynamics of occupation of Brazilian territory by these ecosystems. The information is presented on three occasions, seeking to encourage understanding of where livestock grazing occurs and how the dynamics of occupation of the area was favored by the search. Also, it shows how the research was fundamental for Brazil occupy little arable areas considered, making the country one of the largest producers of cattle in the world.

An Insight into Different Strategies for Control and Prophylaxis of Fasciolosis:A Review

Fasciolosis is one of the important diseases of livestock and has zoonotic importance.Fasciolosis can cause huge economic losses due to decrease in milk and meat production,decreased feed conversion ratio,and cost of treatment.Treatment and prophylaxis strategies for Fasciola infection are formed based on epidemiological data.The control of Fasciola infection can be attained by treating the animals with active anthelmintics.The use of different combinations of anthelmintics with a possible rotation is more effective against immature as well as adult flukes.Control of the intermediate host(snail)is vital for the reduction of fasciolosis.Due to the rapid growth of snails,the eradication is quite difficult in waterlogged and marshy areas.The use of different grazing methods and treatment of grazing areas can also help to control fasciolosis.A variety of antigens generated by Fasciola spp.have been shown to protect against liver fluke infection.The crude antigens,excretory/secretory,and refined antigens and their combination can be used as prophylactic treatment for the control of fasciolosis.The use of any of the single or combination of these methods can be very effective for the control of fasciolosis.

Structural Characteristics of Mulato Grass I under Different Cutting Heights

This work aimed to evaluate the effects of different individual heights of cut on structural characteristics of Brachiaria hibrida cv. Mulato I in four periods of the year. The study was carried out at the Fazenda Experimental Vale do Acaraú, in Sobral, Ceará, Brazil, from January to December, 2008. The experimental design was a split plot, with the plots representing four pasture conditions through manual cuts of 10 cm, 20 cm, 30 cm and 40 cm heights, which were done every 30 days. Each treatment had three replications. The subplots were represented by four periods of evaluation: January-February-March, April-May-June, July-August-September and October-November-December. Fertilization was performed with 350 kg of N/ha, divided into monthly applications. Irrigation was conducted in alternate days during the dry season. The variables studied were: mean height before cutting (cm);dry matter content (%);total dry matter production (t/ha);percentage of leaves;percentage of stems;percentage of dead material;leaf blade/stem ratios;number of total leaves per tiller;number of live leaves per tiller;average size of leaves;and tiller density. Cutting at 10 cm caused a decrease in total dry matter production, underestimating the potential production. Cutting heights between 20 and 30 cm contributed positively to increase the total number of leaves, number of green leaves, average size of the leafs and total dry matter production. Under the present experimental conditions, cutting around 40 cm was not recommended because of a decreasing in the leaf/stem ratio and a increasing in stem fraction and dry matter content, compromising the structure of the canopy.

Improving bermudagrass in the Southeastern United States with alfalfa as an alternative nitrogen source in grazing systems

Background Bermudagrass(Cynodon spp.)is one of the most common perennial warm-season forages grown in the Southeastern United States.The incorporation of alfalfa(Medicago sativa)into bermudagrass pastures could serve as an alternative source of nitrogen(N)while also improving the nutritive value of the forage base.Methods A 2-year grazing evaluation arranged in a randomized complete block design was conducted from May to September 2018(Year 1)and May–August 2019(Year 2)in Tifton,GA,USA.The objective was to compare the production of alfalfa–bermudagrass mixed pastures(BGA)with bermudagrass monoculture pastures with(BGN)or without(BG)the application of synthetic nitrogen on forage production and stocker cattle performance.Results Differences were observed for average daily gain(p=0.10),gain per hectare(p=0.02)and stocking rate(p=0.01),in that BGA was greatest compared to BGN and BG,which did not differ from each other.Furthermore,BGA had increased forage crude protein(p=0.01)and total digestible nutrients(p=0.01)compared to BGN and BG.Finally,BGA provided the greatest economic return per hectare compared to BG or BGN.Conclusions These data illustrate improved animal performance and forage nutritive value using alfalfa–bermudagrass systems and offer a viable option for producers seeking alternatives to synthetic N sources for bermudagrass pastures in the Southeastern United States.

Free-ranging livestock altered the spatiotemporal behavior of the endangered North Chinese leopard (Panthera pardus japonensis) and its prey and intensified human–leopard conflicts

Widespread distribution of livestock in the natural habitats of large carnivores may negatively impact carnivore populations by reducing wild prey availability and increasing human–carnivore conflicts.In this study,we used camera-trapping data collected in the temperate forests of the Taihang Mountains in North China during 2016–2019 to examine whether and how free-ranging cattle affected habitat use and Diel activity patterns of the endangered North Chinese leopard(Panthera pardus japonensis)and its 2 wild prey species,Siberian roe deer(Capreolus pygargus),and wild boar(Sus scrofa).Residents were also interviewed to record livestock depredation events by leopards during 2015–2019.We found that roe deer spatially avoided sites frequented by cattle,but wild boar did not.In the growing seasons,leopards shared habitats with cattle and tended to increase their diurnal activities where cattle were present.All 3 study species exhibitedfine-scale spatial-temporal segregation to cattle.Leopards selectively preyed on calves over adult cattle and livestock depredation frequency was positively correlated with the detection rates of cattle and wild prey,but not that of leopard.Thesefindings not only show that through behavioral adaption large carnivores and their ungulate prey may persist under livestock disturbance,but also highlight how important proper livestock management is for conserving North Chinese leopards in this region.To enhance livestock management and mitigate human–leopard conflicts,we recommend specific actions,such as better guarding of free-ranging cattle or adoption of a captive farming system.

Grassland-based ruminant farming systems in China: Potential, challenges and a way forward

With an increasing demand for high-quality,eco-friendly food products and growing concerns over ecological conservation,the development of ecology-based alternatives for ruminant production in China is urgently needed.This review discusses the capabilities for integrating grassland grazing into existing livestock farming systems to meet the contemporary human needs for high-quality foods and ecologically stable environments.Additionally,this review provides a critical analysis of the challenges and future directions associated with grassland-based ruminant farming systems.Integrating nutritional manipulation with grazing manipulation is critical for improving the productivity of grassland-based ecosystems and natural ecological functions.Biodiversity is the primary determinant of grassland ecosystem functions,while the composition and function of rumen microbiomes determine ruminant production performance.Future studies should focus on the following aspects:1)how livestock grazing regulates grassland biodiversity and the mechanisms of grassland biodiversity maintenance,offering an important scientific basis for guiding grazing manipulation practices,including grazing intensity,livestock types,and grazing management practices;to 2)characterize the microbial ecology within the rumen of grazing ruminants to offer clarified instruction for the nutritional manipulation of grazing ruminants.Our recommendation includes creating a transdisciplinary system that integrates ecology,animal nutrition,and animal behavior to develop grassland-based ruminant farming systems sustainably,thereby achieving high-quality animal production and environmentally sustainable goals.