1.Many studies have investigated why males and females segregate spatially in sexually dimorphic species. These studies have focused primarily on temperate zone ungulates in areas lacking intact predator communities, and few have directly assessed predation rates in different social environments. 2.Data on the movement, social affiliation, mortality and foraging of radio-collared African buffalo (Syncerus caffer) were collected from 2001–06 in the Kruger National Park, South Africa. 3.The vast majority of mortality events were due to lion (Panthera leo) predation, and the mortality hazard associated with being an adult male buffalo in a male-only ‘bachelor’ group was almost four times higher than for adult females in mixed herds. The mortality rates of adult males and females within mixed herds were not statistically different. Mortality sites of male and female buffalo were in areas of low visibility similar to those used by bachelor groups, while mixed herds tended to use more open habitats. 4.Males in bachelor groups ate similar or higher quality food (as indexed by percentage faecal nitrogen), and moved almost a third less distance per day compared with mixed herds. As a result, males in bachelor groups gained more body condition than did males in breeding herds. 5.Recent comparative analyses suggest the activity-budget hypothesis as a common underlying cause of social segregation. However, our intensive study, in an area with an intact predator community showed that male and female buffalo segregated by habitat and supported the predation-risk hypothesis. Male African buffalo appear to trade increased predation risk for additional energy gains in bachelor groups, which presumably leads to increased reproductive success.

Soil biochar application effects in agricultural systems are not well understood. Corn (Zea mays L.), soybean (Glycine max L.), wheat (Triticum aestivum L.), cereal rye (Secale cereal L.), and alfalfa (Medicago sativa L.) were grown on two soils amended with four rates of biochar, a Marietta fine sandy loam (fine-loamy, siliceous, active, thermic Fluvaaquentic Eutrudept) and a Houston silty clay (very fine, smectitic, thermic Oxyaquic Haplaudert) and allowed to equilibrate for 56 days. To investigate a possible nitrogen effect, three nitrogen rates were added to non-legume species. Our results revealed reductions in nutrient uptake across all crops, but this followed the same trend as shoot dry weight production and plant tissue concentration for pots treated with biochar. The significant reduction in uptake and tissue concentration are believed to be linked to smaller plant sizes. Therefore, it is believed that biochar applications are not having an effect on plant growth.

In many pasture and rangeland scenarios, low-quality forages (< 6-8% CP) are the primary energy source for some portion of the year. At these times, energy is typically the first limiting nutrient to the ruminant. Low-quality forages are generally not limited in availability; however, the high cell wall content and reduced levels of CP prevent ruminants from being able to extract the harvested energy. Without provision of supplemental nutrients, the available energy may be inadequate to meet performance expectations. Protein supplementation during periods of inadequate forage quality has been observed to alleviate ruminal nitrogen deficiencies and increase forage utilization. Increased forage utilization translates into greater energy extraction allowing for increased animal performance. The first trial was conducted to evaluate the effects of utilizing non-protein nitrogen (a slow-release urea compared to urea) on intake and digestion of beef steers consuming low-quality bermudagrass hay. Steers were provided ad libitum access to a low-quality bermudagrass hay (7.3 % CP and were ruminally dosed once daily with either urea or slow-release urea (SRU) at levels to provide 0, 64, 128, or 192 mg of N/kg of initial BW per day. Additionally, steers were supplemented with glycerol at levels of 0 or 0.1% of initial BW per day. Total OMI and forage OMI (FOMI) increased quadratically (P < 0.01) with NPN supplementation. However there was not a difference in total OMI or FOMI between urea and the SRU (P = 0.24 and 0.21, respectively). The largest increases in FOMI and total OMI occurred with the first level of supplementation (64 mg N/kg BW) for both urea and SRU and intake peaked when 128 mg N/kg BW was supplemented. Total OMD was not affected by N supplementation level however N from urea tended to elicit a greater response than from the SRU (P = 0.01). Ruminal OMD increased linearly (P = 0.07) and ruminal NDF digestion increased quadratically (P = 0.09) with N supplementation. The second experiment was conducted to evaluate the effects of hay crude protein and protein supplementation on intake and digestion in beef steers. Steers received one of three bermudagrass (Cynodon Dactylon) hays of differing nutritive value (7.0, 8.4, or 13.4% CP) and either 0 or 156 mg N/kg BW supplemented as cottonseed meal once daily. No significant Hay x CSM interactions were observed for hay OMI, total OMI, TDOMI, or digestible NDF intake (P >= 0.67). Hay OMI and total OMI increased linearly (P < 0.01) with hay nutritive value. A quadratic response (P = 0.03) was observed for TDOMI with increasing hay nutritive value. This response was largely driven by a quadratic increase (P < 0.01) in OM digestion with increasing nutritive value of hays. Supplementing CSM generally did not affect HOMI (P = 0.63) although TDOMI (P = 0.03) was increased. Similarly, OM digestion (P = 0.61) and NDF digestion (P = 0.11) were not impacted by CSM supplementation.

The objectives of this study were to assess the effects of prescribed burning on herbaceous and browse forage quality in the aspen forest type for elk and domestic sheep. Plant samples of selected forage species were taken from burned and nonburned plots within three different prescribed burns in southeastern Idaho. These samples were analyzed for in vitro dry matter digestibility, crude protein, calcium and phosphorus. Data were analyzed using the analysis of variance. There was little improvement in forage quality as a result of prescribed burning, with some reduction in quality in 1983 exhibited by pinegrass (Calamagrostis rubescens). Aspen on August 2 , 1982 had improved elk IVDMD and Ca/P ratios, crude protein and phosphorus levels and decreased calcium content on the burned versus the nonburned areas . By August 22, 1982, only crude protein levels were improved. All of the shrubs analyzed for that date had improved crude protein levels on the burned versus the nonburned areas, but only serviceberry had higher phosphorus levels. In 1983, none of the shrubs or forbs had improved forage quality. Pinegrass decreased in IVDMD and c rude protein on the burned areas, possibly due to a more rapid maturation and increased seed production. Other benefits from prescribed burning included a changing species composition from dense shrub matts to more palatable and nutritious forbs that are not found on unburned areas . This reduction in shrubs also led to greater access of animals to available forage. The aspen type was shown to have a nutritious and valuable understory, irrespective of prescribed burning.

Beef cattle producers in the southeastern US often stockpile forage in late summer to extend the grazing season and reduce feeding costs. Three stockpiled grass-legume mixtures were evaluated for winter grazing. In addition, stockpiled forages were ensiled and evaluated as livestock feed. Four accumulation dates and seven harvest dates were randomized to small plots of tall fescue (Festuca arundinacea Schreb.) -red clover (Trifolium pratense L.), orchardgrass (Dactylis glomerata L.) -red clover, and orchardgrass-alfalfa (Medicago sativa L.). The amount of grass and legume in the fescue-red clover mixture shifted from less than 30% grass and more than 60% legume in October to over 60% grass and less than 10% legume in April. All forage mixtures contained at least 15% CP from November to March. Fescue-red clover was higher in TNC and lower in NDF, ADF and cellulose in January and March than the orchardgrass-legume mixtures. Fescue-red clover was higher in yield than the orchardgrass-legume mixtures from November to February. Delaying stockpiling until September 1 or 15 increased (P <.05) legume content and decreased dead grass content in orchardgrass-clover and orchardgrass-alfalfa. Accumulating growth from September 15 increased percent CP in fescue-red clover and orchardgrass-clover, compared to August 15, and decreased percent NDF in all forage mixtures. Percent IVDMD increased in orchardgrass-clover when stockpiling was delayed until September 15. May yields decreased only in orchardgrass-alfalfa when stockpiling was delayed until September. Orchardgrass stockpiled on August 3 and September 3, and alfalfa stockpiled on September 3 were ensiled alone. Chemical composition of silages was determined after 90 d of fermentation. Silages averaged 16.0% CP and 44.7% NDF. Digestibility of the ensiled stockpiled forages was estimated using acid insoluble ash as a marker with 18 wether lambs. No differences were observed in DM or CP digestibility, but NDF digestibility was lower for alfalfa silage than for orchardgrass silages. All stockpiled grass-legume mixtures provided high quality winter grazing, and all silages were of good quality and digestibility. Fescue-red clover maintained both good quality and higher yield than the other mixtures. Ensiling stockpiled alfalfa and orchard grass provided a method of maintaining CP and digestibility for subsequent feeding. / Master of Science

The objective of this study was to determine effects of supplementing coastal bermudagrass (Cynodon dactylon; CBG) hay with Strophostyles helvula (98 g kg-1 crude protein (CP), 476 g kg-1 neutral detergent fiber (NDF)), S. leiosperma (117 g kg-1 CP, 497 g kg-1 NDF), or cottonseed meal (506 g kg-1 CP, 352 g kg-1 NDF; CSM) upon intake of CBG hay (127 g kg-1 CP, 691 g kg-1 NDF) and apparent digestibility of dietary organic matter (OM), NDF, and true digestibility of CP. Six Boer-Spanish goats (46.22 +- 3.99 Kg) were fed CBG plus S. helvula, S. leiosperma, or CSM at 0.34 and 0.68% of BW in a 6*6 Latin square with 3*2 factorial arrangement of treatments. The CBG was fed ad libitum, and the legumes/CSM were fed in two equal daily feedings during a 7-d adjustment period and 7-d collection period in metabolism crates. Feces were collected every 24-h, and CBG, legumes/CSM, and fecal samples were analyzed for OM, NDF, and CP. There were no supplement type*amount interactions (P > 0.05). Supplement type did not affect OM digestibility (P = 0.21), but OM digestibility increased 6.4% (P = 0.05) at the 0.68% versus 0.34% level of supplementation with the legumes or CSM. Supplementation with CSM and S. leiosperma improved NDF digestibility 7% versus supplementation with S. helvula (P = 0.02); and as supplement amount increased NDF digestibility by 5.5% (P = 0.02). The diet supplemented with CSM had the greatest CP digestibility, and S. helvula CP was 6% less digestible than S. leiosperma (P = 0.02). As supplement amount increased, CP digestibility increased 7% (P = 0.01). Intake of DM, OM, and NDF of CBG was unaffected (P = 0.56) by supplementation with CSM, S. helvula, and S. leiosperma, but total diet NDF intake of diets supplemented with CSM and S. helvula was 10.5% less than diet supplemented with S. leiosperma (P = 0.01). Considering digestibility and intake, CSM and S. leiosperma were the best supplements fed in this experiment. Strophostyles leiosperma is recommended as use for diet supplementation for goats when CBG hay basal diet is fed.

Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / This study evaluated the nutritional quality of the forage plants in Namaqualand Granite Renosterveld vegetation in the Kamiesberg uplands of the Leliefontein communal area, South Africa. Determining the quality of forages is one of the most important factors necessary for the effective management of rangelands as it impacts on the nutrient needs of animals and consequently, the grazing capacity in rangelands. The edible portions of various forage plants were collected in the wet and dry seasons in 2012 and 2013 after which the nutritional quality (mineral nutrient content; crude protein (CP); fibre, neutral detergent fibre (NDF) and acid detergent fibre (ADF); dry matter digestibility (DMD); dry matter intake (DMI); metabolizeable energy (ME); and relative forage value (RFV)) as well as the anti-nutritional quality (total phenolics (TP); condensed tannins (CT); and silicon (Si) concentrations) of the plants were determined. Plants were thereafter grouped into their respective growth forms: grasses (15 species), herbs (15 species), leaf succulents (17 species), non-succulents (134 species), reeds (7 species), trees (8 species) and stem succulents (2 species) for statistical analyses. There were generally only a few significant differences for each forage growth form, when comparing the nutritional and anti-nutritional qualities between the two seasons. Certain forage types such as leaf succulents were found to have a high nutritional value in terms of their mineral nutrient content, CP, DMD and ME , but were also found to contain high concentrations of one or more anti-nutritional factors. However, within each season, results showed that for both the nutritional quality and anti-nutritional quality, there was a significant difference between the different growth forms within each season. This suggests that both of these quality parameters are essential in order to draw meaningful conclusions regarding forage quality of these semi-arid rangeland plants. Further research is needed at the species level to determine what plant species are the most nutritious in terms of both nutritional and anti-nutritional quality in order to inform the potential production of these species on a commercial scale.

Made available in DSpace on 2014-06-11T19:28:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-28Bitstream added on 2014-06-13T19:16:11Z : No. of bitstreams: 1 junqueira_jb_me_jabo.pdf: 613418 bytes, checksum: 2d96f9a3a3a9a81ba8c0d4213f5c57be (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Tendo em vista o aumento no número de confinamentos e todos os problemas ambientais gerados pela grande quantidade de dejetos depositados em uma área reduzida, o trabalho visa contribuir com informações que viabilizem a sustentabilidade na criação de bovinos de corte em sistemas intensivos, fomentando a integração de sistemas de criação animal e culturas vegetais, por meio do manejo adequado dos resíduos gerados e posterior aproveitamento na adubação de culturas. Para tanto, objetivou-se com o presente desenvolver os processos de biodigestão anaeróbia e compostagem, avaliando a produção e qualidade do biogás, biofertilizante e composto gerados. Avaliar a aplicação de adubo orgânico (biofertilizante e composto) e adubo mineral em pasto cultivado com a planta forrageira Panicum maximum Jacq. cv. Tanzânia. Foram utilizados os dejetos gerados por bovinos de corte confinados. O material foi destinado à formação de leiras de compostagem e ao abastecimento de biodigestores anaeróbios. O biofertilizante e o composto gerados foram utilizados na adubação da planta forrageira. O uso de adubo mineral promoveu as maiores quantidades de massa de forragem em relação aos demais. As plantas adubadas com biofertilizante obteve a melhor relação lâmina foliar:colmo (1,88). Os teores de proteína na lâmina foliar variaram de 15,62% a 9,2%. A composição bromatológica da forragem da área adubada com adubo orgânico (biofertilizante e composto) foi superior aos da forragem da área adubada com adubo mineral. A adoção da adubação orgânica foi viável, não somente como proposta de modelo de produção sustentável, mas também como forma de incrementar o lucro gerado na atividade / Given the increase in number of confinements and all the environmental problems caused by the large amount of waste deposited in a small area, the work aims to contribute information that will enable sustainability in the farming of beef cattle in intensive systems, fostering systems integration, animal husbandry and crops, through the proper management of waste generated and further use in the fertilization of cultures. To do so, with the objective to develop the processes of this anaerobic digestion and composting, evaluating the yield and quality of gas, fertilizer and compost generated. To evaluate the application of organic manure (compost tea and compost) and mineral fertilizer in the pasture cultivated with forage grass Panicum maximum Jacq. cv. Tanzania. We used the manure generated by beef cattle. The material was used for the formation of windrows for composting and anaerobic digesters to supply. The biofertilizer and compost generated were used in the fertilization of forage. The use of mineral fertilizer produced the greatest amounts of dry matter in relation to others. Plants fertilized with biofertilizer had the best leaf blade: stem ratio (1.88). The protein contents in leaf blade ranged from 15.62% to 9.2%. The chemical composition of the forage area fertilized with organic fertilizer (compost tea and compost) was greater than the area of forage fertilized with mineral fertilizer. The adoption of organic manure was feasible, not only as a proposed model of sustainable production, but also as a way of increasing the profit generated in the activity

Master of Science / Department of Agronomy / Robert M. Aiken / Doohong Min / Finding a high-value forage crop with limited water requirements to produce livestock feed is becoming increasingly important as producers adapt to restricted water supply conditions. Our objectives were to determine the forage yield, nutritive values, and crop water productivity (CWP) of teff grass (Eragrostis tef [Zucc.] Trotter) under field conditions when compared to sorghum sudangrass (SS, S. x drummondii[(Nees ex. Steud.) Millsp. & Chase]) and pearl millet (PM, P. glaucum [L.]R.Br.). Crop water productivity was determined by dividing above-ground biomass by crop water use. Crop water use was determined by the summation of soil water depletion, precipitation, and irrigation. Yield was determined by quadrat area clippings of above-ground biomass. Nutritive value was determined using wet chemical analysis. Cultivars showed significant differences in biomass production and CWP in both years. Excalibur teff grass variety had the greatest CWP (418 kg ha-1 cm-1) 40 days after planting (DAP) in 2016, and was similar to SS and PM for the rest of the season until 58 DAP. Pearl millet had the greatest overall CWP (443 kg ha-1 cm-1) at 44 DAP. In 2017, sorghum sudangrass had significantly greater CWP than teff grass and pearl millet throughout most of the season. Among the teff varieties, Haymore had the greatest CWP (239 kg ha-1 cm-1) when harvested 10 days after boot stage (DAB). Crude protein values of teff grass varieties ranged from 9.3% to 21.3%, depending on the harvest date and year. Teff grass showed equivalent or greater nitrogen use efficiency (27.8 – 88.8 kg biomass kg-1 N applied) in our study than previously reported. Teff grass demonstrated potential to provide producers with a fast-growing and competitive forage crop with less overall water use due to a shortened growing season.

Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / The Overberg renosterveld rangelands of the Cape Floristic Region (CFR) has become well associated with commercial and communal agricultural practices, namely crop and livestock production. This Mediterranean region is characterized as being a semi-arid, winter rainfall area with nutrient-limited soils. Livestock farmers rely largely on introduced legume species such as lucerne (Medicago sativa) as high quality forage to sustain their livestock’s diets. Generally, these introduced species are reliant on the accessibility of water and nutrients, due to the specific climatic and edaphic conditions of the region. The availability of high quality forage has always been a major concern to farmers when it comes to managing their livestock, since livestock productivity is determined by the quality of the forage consumed.