The conversion of native forest to agricultural land has been an on-going issue threatening the health of New Zealand’s freshwater systems. However, despite the fact that this has been occurring since early European settlement, our understanding of the mechanistic relationships between riparian vegetation and stream condition are poorly developed. This research investigated: (i) how forests affect downstream benthic macroinvertebrate communities in pasture and the environmental factors driving community change; (ii) how upstream forest size impacted the rate of change in downstream environmental drivers and associated macroinvertebrate community structure; and (iii) whether the addition of coarse particulate organic matter (a single potential driver of forest community structure) can reset community structure to that of a forested state. Physico-chemical conditions, basal energy resources, and macroinvertebrates were surveyed in several New Zealand headwater streams. At Mount Egmont National Park, 10-12 sites were surveyed across a longitudinal forest-pasture gradient in each of five streams flowing from continuous forest to dairy farmland. My results showed that forests can have marked effects downstream. From the forest edge, water temperatures increased consistently, with a rise of approximately 0.2ºC per 100 m of downstream distance. By contrast, coarse particulate organic matter (CPOM) decreased rapidly downstream of the forest, however, low levels of “forest-derived” CPOM were still present 300m downstream from the forest edge. These environmental changes drove significant shifts in macroinvertebrate community structure. Moreover, pasture communities were markedly different from those in forest, despite being only 100 m from the forest edge. In particular, total macroinvertebrate and EPT richness and densities decreased, and communities shifted from evenly distributed allochthonous-based communities to autochthonous-based communities, highly dominated by molluscs (e.g., Potamopyrgus spp.) Subsequent surveys of 6-8 sites across a longitudinal forest-pasture gradient in each of eleven streams flowing from forest fragments of different sizes into grazed pastures throughout the Canterbury region, indicated that stream temperature increased more rapidly downstream of small- and medium-sized fragments, than larger fragments. A Berger-Parker dominance index also indicated that macroinvertebrates responded principally to water temperature, with communities being more highly dominated by temperature-tolerant molluscs in streams flowing from small-sized forest fragments. Several headwater streams in Canterbury were also highly retentive, with marked CPOM rarely exported beyond 50 m downstream of the forest. Experimental additions of leaf litter to the pasture reaches of the same streams dramatically increased amounts of stored benthic CPOM. Although non-significant, trends indicated that EPT and shredder densities increased at litter addition sites, providing promise that CPOM can function as a mechanism directly enhancing healthy stream communities. My findings support the contention that when the replanting of entire stream reaches is infeasible, the use of riparian management strategies which focus on the planting of intermittent patches along stream banks can potentially improve stream habitat and community health downstream.

Kiwifruit are of huge economic importance for New Zealand representing 29 percent of total horticultural exports. Fruit size is the biggest determinant of what consumers are willing to pay, and there is also a positive relationship between consumer preference for flavour and percentage dry matter. The two main cultivars exported from New Zealand are Actinidia chinensis ‘Hort 16A’ (gold kiwifruit) and A. deliciosa ‘Hayward’ (green kiwifruit). Under current commercial practice the only product allowed for use on kiwifruit to increase fruit size in New Zealand is Benefit®. Benefit® has been shown to induce different results when applied to A. chinensis and A. deliciosa, whereas synthetic plant growth regulators such as the cytokinin-like substance N-(2- chloro-4-pyridyl)-N’-phenylurea (CPPU) have been found to promote similar increases in fresh weight of fruit in both cultivars. Final fruit size is determined by both cell division and cell enlargement. It was been shown that fresh weight can be increased in both of the major Actinidia cultivars even though their physiology differs. Hormonal control of fruit size in relation to cell division and cell enlargement phases of fruit growth was studied in both A. chinensis and A. deliciosa. CPPU was applied to both cultivars in a growth response experiment where fruit were collected throughout the growing season. The objective of this experiment was to create growth curves, to compare and contrast the effect on A. chinensis and A. deliciosa, and to provide material for hormone analysis. Application of CPPU was found to significantly increase the fresh weight of both A. chinensis and A. deliciosa fruit (46.98 and 31.34 g increases respectively), and alter the ratio of inner and outer pericarps of A. chinensis fruit. CPPU and Benefit® were applied individually and together to both cultivars. It was found that only A. chinesis fruit were affected by the application of Benefit®; fresh weight was increased by 26.38 g, and percentage dry matter was significantly reduced. There was a statistically significant (p < 0.05) interaction between CPPU and Benefit® when applied to A. chinensis. 3,5,6-trichloro-2-pyridyloxyacetic acid (3,5,6-TPA) was applied to A. deliciosa on two application dates at three concentrations and was found to decrease fresh weight of fruit, but significantly increase percentage dry matter regardless of application date or concentration. Lastly CPPU and 1-naphthalene acetic acid (NAA) were applied to A. deliciosa at two application dates and in all combinations. Application date affected the response to both a low concentration of CPPU and NAA. A synergistic interaction was observed when CPPU was applied early plus NAA late (CPPU early (4.53 g increase) plus NAA late (13.29 g) < CPPU early plus NAA late (33.85 g). Finally endogenous hormone content was studied. Methods were developed and tested for the simultaneous analysis of both indole-3-acetic acid (IAA) and cytokinins. Freeze dried fruit were purified using Waters Sep-pak® cartridges and Oasis® columns then IAA was quantified by high pressure liquid chromatography. Preliminary results indicate a correlation between application of CPPU and endogenous IAA, high concentrations of IAA correlated well with periods of rapid fruit growth particularly for CPPU treated fruit.

Copy of author's previously published work inserted. / Bibliography: leaves 261-306. / xxix, 308 leaves : ill. (some col.), maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The objectives of the project were: i. to determine whether there are competitive interactions between Aporrectodea trapezoides and A. caliginosa and A. rosea.--ii. to investigate compeditive interactions between A. calignosa, Microscolex dubius and A. trapezoides.--iii . to determine the likely impact of A. longa on soil fauna, especially the native earthworm, Gemascolex lateralis, in native ecosystems. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, 1996

Content removed due to copyright restrictions: Burggraaf, V.T., Kemp, P.D., Thom, E.R., Waghorn,G.C., Woodfield, D.R. & Woodward, S.L. (2004) Performance of dairy cows grazing white clover selected for increased floral condensed tannin. Preliminary report from experiments presented in Chapter 4 published in the 2004 Proceedings of the New Zealand Grassland Association. / Legumes containing 20 to 40 g of condensed tannin (CT) per kg of dry matter (DM) can improve dairy cow milk production by reducing ruminal protein degradation to ammonia and preventing bloat. White clover (Triflium repens L.) produces CT in its flower heads. High tannin (HT) white clover, bred for increased flowering and increased floral CT concentration, was evaluated under dairy grazing in Hamilton, New Zealand. Its performance in monoculture was compared to that of Grasslands Huia white clover over two years, and five short-term grazing experiments determined its effects on Friesian dairy cows. Huia and HT had similar floral CT concentrations, ranging from 15 to 77 g/kg DM over two flowering seasons. HT clover had higher flower densities than Huia until the second summer after sowing, resulting in higher clover (leaf plus flower) CT concentrations. Clover CT peaked at 12.1 g/kg DM for HT and 5.7 g/kg DM for Huia. HT swards had lower stolon growing point densities than Huia swards and annual DM yields averaged 10.0 and 11.0 t DM/ha for the respective clovers. The ingress of non-sown white clover genotypes reduced treatment differences in the last 10 months of the experiment. Mild bloat occurred in cows grazing both clovers. Cows grazing HT white clover had rumen ammonia concentrations 5 to 26% lower than that of cows grazing Huia, indicating less proteolysis in the rumen of HT cows, but there were no consistent effects on rumen soluble protein or volatile fatty acids (VFA). Differences between treatments in dietary CT concentrations were too small to affect milk production or composition. Minced mixtures of 0, 25, 50, 75 or 100% of DM as white clover flower with the remainder as white clover leaf, were incubated in vitro and rumen metabolite concentrations determined at 0, 2 ,4, 8, 12 and 24 hours. Polyethylene glycol was added to one of the 50% flower treatments to inactivate CT. Clover flowers had less soluble protein than leaves at 0 hours, and increasing the percentage of flowers from 0 to 100% reduced the net conversion of plant-N to ammonia-N from 29 to 12%. The contribution of CT to these effects was small. Increasing percentages of clover flowers did not significantly affect total VFA production but increased acetate to propionate (A:P) ratios. White clover CT decreased A:P ratios. In another in vitro experiment perennial ryegrass leaf (Lolium perenne L.) was incubated either alone or with white clover flowers or birdsfoot trefoil (Lotus corniculatus L.). Clover flowers were more effective at reducing proteolysis than birdsfoot trefoil, due largely to less release of soluble protein, but birdsfoot trefoil treatments had the lowest A:P ratios. In conclusion, HT clover had higher forage CT concentrations than Huia because of increased flowering. Increased flowering reduced the agronomic performance of HT and lowered rumen ammonia concentrations, but did not increase milk production or prevent bloat. White clover flowers reduced rumen proteolysis in vitro, but this was mainly a result of their low protein concentration. White clover CT and birdsfoot trefoil forage benefited the molar percentages of VFA, but increasing the proportion of clover flowers did not. Further increases in white clover CT concentrations may benefit ruminant performance, but this should not be implemented through increased flowering.

Content removed due to copyright restrictions: Burggraaf, V.T., Kemp, P.D., Thom, E.R., Waghorn,G.C., Woodfield, D.R. & Woodward, S.L. (2004) Performance of dairy cows grazing white clover selected for increased floral condensed tannin. Preliminary report from experiments presented in Chapter 4 published in the 2004 Proceedings of the New Zealand Grassland Association. / Legumes containing 20 to 40 g of condensed tannin (CT) per kg of dry matter (DM) can improve dairy cow milk production by reducing ruminal protein degradation to ammonia and preventing bloat. White clover (Triflium repens L.) produces CT in its flower heads. High tannin (HT) white clover, bred for increased flowering and increased floral CT concentration, was evaluated under dairy grazing in Hamilton, New Zealand. Its performance in monoculture was compared to that of Grasslands Huia white clover over two years, and five short-term grazing experiments determined its effects on Friesian dairy cows. Huia and HT had similar floral CT concentrations, ranging from 15 to 77 g/kg DM over two flowering seasons. HT clover had higher flower densities than Huia until the second summer after sowing, resulting in higher clover (leaf plus flower) CT concentrations. Clover CT peaked at 12.1 g/kg DM for HT and 5.7 g/kg DM for Huia. HT swards had lower stolon growing point densities than Huia swards and annual DM yields averaged 10.0 and 11.0 t DM/ha for the respective clovers. The ingress of non-sown white clover genotypes reduced treatment differences in the last 10 months of the experiment. Mild bloat occurred in cows grazing both clovers. Cows grazing HT white clover had rumen ammonia concentrations 5 to 26% lower than that of cows grazing Huia, indicating less proteolysis in the rumen of HT cows, but there were no consistent effects on rumen soluble protein or volatile fatty acids (VFA). Differences between treatments in dietary CT concentrations were too small to affect milk production or composition. Minced mixtures of 0, 25, 50, 75 or 100% of DM as white clover flower with the remainder as white clover leaf, were incubated in vitro and rumen metabolite concentrations determined at 0, 2 ,4, 8, 12 and 24 hours. Polyethylene glycol was added to one of the 50% flower treatments to inactivate CT. Clover flowers had less soluble protein than leaves at 0 hours, and increasing the percentage of flowers from 0 to 100% reduced the net conversion of plant-N to ammonia-N from 29 to 12%. The contribution of CT to these effects was small. Increasing percentages of clover flowers did not significantly affect total VFA production but increased acetate to propionate (A:P) ratios. White clover CT decreased A:P ratios. In another in vitro experiment perennial ryegrass leaf (Lolium perenne L.) was incubated either alone or with white clover flowers or birdsfoot trefoil (Lotus corniculatus L.). Clover flowers were more effective at reducing proteolysis than birdsfoot trefoil, due largely to less release of soluble protein, but birdsfoot trefoil treatments had the lowest A:P ratios. In conclusion, HT clover had higher forage CT concentrations than Huia because of increased flowering. Increased flowering reduced the agronomic performance of HT and lowered rumen ammonia concentrations, but did not increase milk production or prevent bloat. White clover flowers reduced rumen proteolysis in vitro, but this was mainly a result of their low protein concentration. White clover CT and birdsfoot trefoil forage benefited the molar percentages of VFA, but increasing the proportion of clover flowers did not. Further increases in white clover CT concentrations may benefit ruminant performance, but this should not be implemented through increased flowering.

Two field grazing experiments were conducted in New Zealand (NZ) in spring (Experiment 1; November 2008) and autumn (Experiment 2; April 2009) to evaluate the effects of feeding a high sugar perennial ryegrass (HSG; cv. AberDart; derived in the United Kingdom; UK) versus a NZ- derived control grass (cv. Impact) on milk production and estimated nitrogen (N) partitioning within the cow. Areas of both ryegrasses were replicated and sown with or without white clover (cl) (HSG+cl, control+cl, HSG and control). A cross-over design with four 10-day periods was used in each experiment, using 15 Friesian cows per treatment per period in Experiment 1 and 5 cows per treatment per period in Experiment 2. Treatment effects upon pasture botanical and chemical composition, cows’ milk yield and composition, and estimated N partitioning were studied. Nitrogen partitioning was calculated using indirect methods. Herbage concentrations of water soluble carbohydrates (WSC) were lower in autumn than in spring whilst crude protein (CP) concentrations were higher in autumn. Organic matter digestibility (OMD) and metabolisable energy (ME) concentration was similar in both seasons. There were no differences in the concentration of CP, WSC and dry matter (DM) among treatments in Experiment 1. The HSG+cl treatment had the lowest concentrations of neutral detergent fibre (NDF, 417 g/kg DM) and the highest content of ME (12.6 MJ/kg DM) and tended to have the lowest sward dead matter content compared with the other three treatments. In Experiment 2 both HSG treatments showed higher concentrations of WSC (15 g/kg DM) compared with the control, both with and without clover; the concentrations of NDF and acid detergent fibre (ADF) were the lowest for both HSG treatments. In Experiment 1, cows grazing treatments with white clover produced more milk (1.6 kg/day) and more milk solids (MS; 0.16 kg/day) than cows grazing pure ryegrass swards ( P< 0.01), with highest milk yields being from cows grazing the HSG+cl treatment (ryegrass cultivar x white clover interaction P<0.05). No differences in milk production were found in Experiment 2. Estimated urinary N excretion (g/day) was similar for all treatments in both seasons, although N intake differed among treatments. The proportion of N intake excreted in urine or secreted in milk was similar for all treatments in both experiments. Nitrogen output (g/day) in milk was the highest for the HSG+cl treatment in Experiment 1 but no differences were found in Experiment 2. Data were combined from both experiments to study the effects of the herbage CP:WSC ratio upon estimated N partitioning between milk and urine. Mean ratios were 0.72 for spring herbage and 2.27 for autumn herbage. As the amount of WSC increased in the diet relative to the amount of CP (thus a lower CP:WSC ratio) there was a significant increase in the amount of milk N secreted per unit of N intake in spring but not in autumn. The breakpoint in the relationship between the herbage CP:WSC ratio and the nitrogen utilisation efficiency for milk production (NUEm) was 1.32, and the NUEm for that breakpoint was 14 g milk N per 100 g N intake. Ratios below this point were associated with improved efficiency of converting pasture N to milk N; ratios above this point were not correlated with changes in N conversion efficiency. It is concluded that the CP:WSC ratio in perennial ryegrass may be important in the partition of absorbed N into milk or urine. A NZ-selected HSG with a lower CP:WSC ratio is likely to have major benefits for pastoral farming in NZ. In order to be effective, a NZ-derived HSG should substantially increase WSC concentration in autumn pasture (from approximately 100 to 200 g/kg DM) whilst reducing CP content simultaneously (from 240 to 190 g/kg DM). The lower structural fibre and higher milk production for the HSG+cl treatment in both experiments suggest that under NZ conditions, best productive responses to HSG may be obtained in management systems that include white clover.

The main object of this study was to investigate the effects of predation by starlings (Sturnus vulgaris) on populations of the grass grub (Costelytra zealandica) in Canterbury, with the secondary objective of investigating the feasibility of life table studies of grass grub populations under Canterbury conditions. Study plots were established in four areas, two on non-irrigated pastureland at Lincoln and Weka Pass and two on irrigated pastureland at Winchmore. A third study plot was established at Winchmore in the second year of field work.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In the period May-November 2007 experiment was conducted in an area of the Federal University of Santa Maria, was studied the relationship between the pasture dynamics and the ingestive behavior of lambs, grazing Italian ryegrass (Lolium multiflorum Lam.) and red clover (Trifolium pratense L.) pasture under different defoliation intensities. Rotational grazing was used and the interval between grazing cycle was determined by the thermal sum of 313 degree-days. The evaluations of ingestive behavior were made by visual observation, in four continuous periods of 24 hours. The values of disappearance of the initial sward height were 65 ( very high ), 58 ( high ), 47 ( mean ) and 37% ( low ), respectively, showing the defoliation intensities. The sward vertical structure was similar among defoliation intensities. The forage allowance decreased linearly as the defoliation intensities increased. For each percent on the forage allowance, there were a decreasing of 0.35 on bite/minute. Bite rate and the number of bites/feeding station were reduced by the diminution of the leaf contribution on the pasture structure, resulting the cycle of pasture, accompanied by the increase of NDF and decrease of CP levels of the forage ingested by lambs. The change of pasture phonological stage proved to be more important than the defoliation intensities tested to cause changes in displacement patterns and feeding stations of lambs. / No período de maio a novembro de 2007 foi desenvolvido experimento em área da Universidade Federal de Santa Maria, no qual foi estudada a relação entre a dinâmica do pasto e o comportamento ingestivo de cordeiras em pastagem de azevém (Lolium multiflorum Lam.) e trevo vermelho (Trifolium pratense L.), sob diferentes intensidades de desfolha. O pastejo foi rotacionado e o intervalo entre pastejos foi determinado pela soma térmica de 313 grausdia. O comportamento ingestivo foi avaliado por meio de avaliação visual, realizada em quatro períodos contínuos de 24 horas. Os valores de desaparecimento da altura inicial do dossel foram de 65 ( muito alta ), 58 ( alta ), 47 ( média ) e 37% ( baixa ), respectivamente, caracterizando as intensidades de desfolha. A estrutura vertical do pasto foi semelhante entre as intensidades de desfolha testadas. A oferta de forragem diminuiu linearmente com o aumento da intensidade de desfolha. Houve diminuição de 0,35 bocados/minutos a cada 1% a mais na oferta de forragem. A taxa de bocados e o número de bocados/estação alimentar foram reduzidos pela diminuição da contribuição de folhas na estrutura da pastagem decorrente do ciclo do pasto, acompanhada do aumento do teor de FDN e redução do teor de PB no pasto ingerido pelas cordeiras. A mudança de estádios fenológicos do pasto mostrou ser mais importante do que as intensidades de desfolha testadas para provocar mudanças nos padrões de deslocamento e estações alimentares de cordeiras.

The main aim of this thesis was to evaluate the methods and intensity of use of grasslands that have an impact on the value of the forage and biomass production. The analysis of the selected four sites with different types of management. They chose two meadows and pastures two, of which one pasture is used in a combined manner.

ARAÚJO, Jucivânia Furtado. Avaliação do uso de diferimento com capim massai em semiárido cearense. 2012. 89 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Zootecnia, Fortaleza-CE, 2012 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-01T15:39:56Z No. of bitstreams: 1 2012_dis_jfaraujo.pdf: 811099 bytes, checksum: dbc0c74a04dafc3c35e023bbef3a9512 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-01T15:40:24Z (GMT) No. of bitstreams: 1 2012_dis_jfaraujo.pdf: 811099 bytes, checksum: dbc0c74a04dafc3c35e023bbef3a9512 (MD5) / Made available in DSpace on 2016-08-01T15:40:24Z (GMT). No. of bitstreams: 1 2012_dis_jfaraujo.pdf: 811099 bytes, checksum: dbc0c74a04dafc3c35e023bbef3a9512 (MD5) Previous issue date: 2012 / The evaluation of management of massai grass under conditions of deferral may contribute to the strategic reserve of forage quality for the dry periods in Northeast Brazil. Based on this assumption, the study aimed to evaluate the massai grass agronomic efficiency in an area of thinned caatinga under semiarid conditions in Brazil, in two closure times (60 and 90 days after of standardization cut, that occurred 30 days after the onset of the rainy season) and four seasons of utilizatione (30, 60, 90 and 120 days after the end of the rainy season). The experiment followed a randomized block with split plot design in a factorial 2 x 4 (2 times of fencing and 4 times of use) with three replicates per treatment. Following parameters were evaluated: total dry mass of forage (TDMF), dry mass of forage dead (DMFD), dry mass of green forage (DMGF), dry mass of green blade (DMGB), dry matter of green stem (DMGS), leaf/stem ratio (L/S), sward height (SH), stretched plant height (SPH), number of leaves per tiller, tiller population density (TPD), intercepted photosynthetically active index (IPAI) and leaf area index (LAI). They were evaluated the dry matter (% DM), organic matter (% OM), crude protein (% CP), neutral detergent fiber (% NDF), acid detergent fiber (% ADF), hemicellulose (% HCEL) cellulose (CEL%), lignin (LIG%) and in vitro digestibility of dry matter (% IVDMD) for the components of leaf fodder and senescent material. At unfolding of interaction for TDMF, there was a quadratic effect for closure time of 90 days, with the point of maximum forage yield at 71 days of use. As for DMGF and DMGB, there was a linear effect for 60 days and quadratic effect for 90 days, with a maximum reached at 49 days of use for DMGF and 33 days for DMGB. In relation to DMGS there was significant effect only for 90 days of closure with maximum estimated at 812.2 kg / ha at 86 days of use. For DMFD was observed that for both closure times the best model is the quadratic response. 102 and 100 days provided higher biomass values of DMFD, with estimates of 3000 and 4337 kg/ha to 60 and 90 closure days, respectively. For L/S ratio, it was observed that the closure time of 60 days, the model that best fitted data was quadratic, while for 90 closure days, the model that best fitted data was linear decreasing. For variables SH and SPH was observed linear decrease as the increase of utilization time with estimated values: 44.8 and 23.5 cm for SH and 97.92 and 63.63 cm for SPH on utilization times of 30 and 120 days, respectively. L/S ratio was reduced with utilization time of massai grass, with estimates of 3.04 and 1.5 leaves per tiller, with 30 and 120 days of utilization times, respectively. It was observed a linear reduction in TPD. For each day of regrowth, there was a reduction of two tillers/m². IPAI and LAI reduced with time of deferral, with estimates of 93 and 84% for IPAI and 4.79 and 3.71 for LAI considering utilization times of 30 and 120 days, respectively. The results were subjected to analysis of variance by F test and when significant portions held the unfolding applying the Tukey test (p <0.05) and regression analysis for the subplots and interactions significant (p<0,05). Statistical analyzes were performed with the aid of the software SISVAR. The increase of closure time of massai grass promotes elevation of biomass components, but compromises the quality of the pasture due to increased biomass of stems. Utilization in dry season must be made within 33 days, due to the intensification of senescence and death of leaves and tillers. The use of Massai grass 30 days after a period of 90 days of fencing ensures an adequate supply of fodder nutritional value. Climatic conditions affect on the chemical composition of Massai grass. The improvement in relative humidity and the occurrence of rainfall, after water restriction, can even improve its nutritional value. / A avaliação do manejo do capim-massai (Panicum maximum x Panicum infestum) em condições de diferimento pode contribuir para a reserva estratégica de forragem de qualidade para os períodos de estiagem no Semiárido brasileiro. Objetivou-se, com o presente trabalho, avaliar a eficiência agronômica e a composição bromatológica da referida gramínea em área de caatinga raleada, em dois períodos de vedação (60 e 90 dias após o corte de uniformização) e quatro épocas de utilização (30, 60, 90 e 120 dias após o término do período chuvoso). O delineamento utilizado foi em blocos ao acaso em esquema de parcelas subdivididas (2 x 4), com duas épocas de vedação (parcelas) e quatro épocas de utilização (subparcelas), com três repetições. Foram avaliados: massa seca de forragem total (MSFT), massa seca de forragem morta (MSFM), massa seca de forragem verde (MSFV), massa seca de lâminas foliares verdes (MSLF), massa seca de colmos verdes (MSCV), relação folha/colmo (F/C), altura do pasto (AP), número de folhas vivas por perfilho (F/P), densidade populacional de perfilhos (DPP), interceptação fotossinteticamente ativa (IRFA) e índice de área foliar (IAF). Também foram avaliados os teores de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), hemicelulose (HCEL), celulose (CEL), lignina (LIG) e digestibilidade in vitro da matéria seca (DIVMS) relativos aos componentes folha da forragem acamada e não acamada e material senescente. Em relação aos períodos de vedação, observaram-se resultados significativos somente para os componentes de biomassa do pasto (MSFT, MSFV, MSLF, MSCV, MSFM e F/C) com valores superiores para 90 dias de vedação. Pelo desdobramento da interação para MSFT, observou-se máxima produção de forragem aos 71 dias de utilização. Para MSFV e MSLF, observou-se efeito linear decrescente para 60 dias de vedação e quadrático para 90 dias de vedação. Em relação à MSCV houve significância apenas para 90 dias de vedação, com máximo estimado em 812,2 kg/ha, aos 86 dias de uso. Para MSFM, em torno dos 100 dias de utilização, verificaram-se os maiores valores. Para a relação F/C, em 90 dias de vedação, houve redução linear. Para as variáveis AP, F/P e DPP, também foram observadas reduções lineares em função da elevação do período de uso. No caso da DPP, para cada dia de rebrotação, houve diminuição de dois perfilhos/m². A IRFA e o IAF foram reduzidos com o tempo de diferimento. Houve efeito significativo de época de vedação sobre o período de utilização apenas para a %PB e %DIVMS das folhas e para a %MS e %HCEL do material senescente. O prolongamento do período de vedação do capim-massai promove elevação dos componentes de biomassa, porém compromete a qualidade do pasto devido ao aumento da biomassa de colmos. A utilização na época seca deve ser feita em até 33 dias, devido à intensificação da senescência e morte de folhas e de perfilhos após esse referencial de dias. Além disso, a utilização do capim Massai 30 dias após um período de vedação de 90 dias ainda garante um suprimento forrageiro de adequado valor nutritivo. O aumento da umidade relativa do ar e a ocorrência de precipitações pluviométricas, após restrição hídrica, estimulam a rebrotação resultando em melhoria do valor nutritivo do capim.