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1.
Sci. agric ; 79(02): 1-10, 2022. ilus, tab, graf
Article in English | VETINDEX | ID: biblio-1498024

ABSTRACT

Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p < 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.


Subject(s)
Arachis/growth & development , Brachiaria/growth & development , Poaceae/growth & development
2.
Sci. agric. ; 79(2)2022.
Article in English | VETINDEX | ID: vti-762539

ABSTRACT

ABSTRACT: Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.

3.
Rev. bras. zootec ; 51: e20210198, 2022.
Article in English | VETINDEX | ID: biblio-1442843

ABSTRACT

Integrating warm-climate forage legumes into grass monocultures has received significant research attention during the past 70 years, but widespread adoption by end users has been elusive. The objectives of this review are to provide historical context regarding legume use in warm-climate grasslands; synthesize the current literature addressing contributions to grassland ecosystem services of warm-climate, grass-only vs. legume-grass mixed swards; and consider how to achieve more widespread adoption of legume technology in warm climates. For this review, warm-climate grasslands are considered those in areas between latitudes 30° N and 30° S, where C4 perennial grasses dominate. The literature suggests measurable advantages in animal performance, soil carbon accumulation, and nutrient cycling of legume-grass mixtures are most likely when grass-only swards receive little or no N fertilizer. Advantages are less or may disappear when mixtures are compared with grasses receiving high N fertilizer rates. In contrast, amelioration of greenhouse gas emissions is often most pronounced for mixtures when compared with grass-only swards receiving high rates of N, because of the magnitude of N fertilizer effects on emissions. Going forward, there is need to focus on selecting for, and thoroughly documenting legume persistence, achieving low-risk and affordable legume establishment methods, assessing compatibility of legumes in mixture with grasses prior to legume cultivar release, emphasizing adoption of both legume species and optimal management practices, and recognizing scientists must assume a larger and more intentional role in encouraging adoption by end-users of research innovations, in addition to our traditional role in technology and product development.(AU)


Subject(s)
Pasture , Ecosystem , Fabaceae/chemistry
4.
Sci. agric ; 79(2): e20200090, 2022. tab, ilus
Article in English | VETINDEX | ID: biblio-1290181

ABSTRACT

Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p < 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.


Subject(s)
Arachis , Pasture/analysis , Brachiaria , Cattle , Fabaceae
5.
J Environ Qual ; 49(6): 1453-1466, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33058171

ABSTRACT

Cattle excreta and nitrogen (N) fertilizer deposited on tropical grasslands are important sources of ammonia (NH3 ) emission. We conducted three field trials (wet, intermediate, and dry conditions) to quantify NH3 emissions from urea fertilizer and simulated excretions of heifer urine and dung on warm-climate grasslands in Brazil. Heifer excreta were derived from pastures of palisadegrass [Urochloa brizantha (Hochst. ex A. Rich.) R. D. Webster 'Marandu'] under three forms of N supply (without or with N fertilization [0 or 150 kg N ha-1  yr-1 ] or mixed with forage peanut [Arachis pintoi 'Amarillo']). Cumulative NH3 -N emissions across rainfall conditions were 7.6-16.6% (mean, 11.7%) for urine, 1.4-2.9% (mean, 2.0%) for dung, and 11.2-20.5% (mean, 14.8%) for urea. Ammonia loss from urine was significantly greater than from dung under all rainfall conditions. Emission from urine and dung differed from those when urea was applied on palisadegrass. There were greater NH3 emissions from urine in the wetter times of the year. Heifer excreta from N-fertilized pasture had greater NH3 emission than excreta from the grass-legume mixture and unfertilized palisadegrass. Urea applied on palisadegrass presented greater NH3 emissions in wet rainfall conditions compared with dry conditions but did not differ from intermediate conditions. Our study showed that N-fertilized systems increase N losses as NH3 emission from excreta, and emissions from urea fertilizer must be included in this system. Heifer excreta and urea fertilizer deposited on warm-climate grasslands increased the NH3 emissions mainly under wet conditions.


Subject(s)
Ammonia , Nitrogen , Affect , Ammonia/analysis , Animals , Brazil , Cattle , Female , Nitrogen/analysis , Urea
6.
Ci. Rural ; 49(1): e20180324, Feb. 11, 2019. tab
Article in English | VETINDEX | ID: vti-18186

ABSTRACT

The objective of this study was to evaluate the productive potential and mineral composition of the forage cactus IPA-Sertânia (Nopalea cochenillifera Salm Dyck). This species was analyzed both in monoculture and intercropped with leucaena [Leucaena leucocephala (Lam.) De Wit.] and gliricidia [Gliricidia sepium (Jacq. Steud.], and was assessed with different sources of manure (cattle, sheep, goat, and broiler litter) serving as fertilizer. The experiment was conducted at the Experimental Station of the Instituto Agronômico de Pernambuco in Caruaru, PE, Brazil. Treatments were allocated in a split-plot arrangement in a randomized complete block design, with four replications. Main plots consisted of cropping systems, while the split-plots were dedicated to manure sources. Cactus harvest was carried out after two years of regrowth. Response variables included both production and nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) concentrations. No differences were observed for cactus production between the cropping systems, with an average value of 22.1Mg dry matter ha-1 2 years-1. In the intercropped systems, greater proximity to the legumes increased the production of the cactus in the treatments with the cattle and sheep manure, and increased the concentrations of P, K, and Mg, but not of N. The introduction of tree legumes, along with the application of manure, contributes to an increase in production and nutrient concentration of IPA-Sertânia cactus.(AU)


Objetivou-se avaliar o potencial produtivo e a composição mineral da palma forrageira IPA-Sertânia (Nopalea cochenillifera Salm Dyck), em cultivo isolado e consorciada com leucena [Leucaena leucocephala (Lam.) de Wit.] ou gliricídia [Gliricidia sepium (Jacq.) Steud.], e adubada com as fontes de esterco bovino, ovino, caprino e cama de frango. O experimento foi conduzido na Estação Experimental do Instituto Agronômico de Pernambuco - IPA, em Caruaru. O delineamento foi casualizado em blocos, em parcelas subdivididas, com quatro repetições. As parcelas foram representadas pelos sistemas de cultivo e as subparcelas pelas fontes de esterco. A colheita da palma foi realizada aos dois anos de crescimento e analisada quanto à produção e aos teores de nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca) e magnésio (Mg). Não foram observadas diferenças de produção da palma entre os sistemas de cultivo, atingindo valor médio de 22,1t ha-1 2 anos-1 de matéria seca (MS). Nos sistemas consorciados, a maior proximidade com as leguminosas incrementou a produção da palma, nos tratamentos com os estercos bovino e ovino, e elevou os teores de P, K e Mg, mas não os teores de N. A introdução de leguminosas arbóreas, juntamente com a aplicação dos estercos, contribui para elevar a produção e os níveis de nutrientes da palma IPA-Sertânia. (AU)

7.
Rev. Bras. Zootec. (Online) ; 48: e20180134, 2019. graf, tab
Article in English | VETINDEX | ID: biblio-1510308

ABSTRACT

The objective was to evaluate the effect of three stocking rates (2, 3.9, and 5.8 animal units ha−1) and three fertilization levels (0, 150, and 300 kg N ha−1 yr−1) on herbage mass and nutritive value of elephantgrass (Pennisetum purpureum Schum.) cv. IRI-381. The experiment was conducted from May to August of 2009 and 2010 in Itambé, PE, Brazil, during the rainy season. Treatments were allocated in a split-plot arrangement in a completely randomized block design. The variables measured included leaf mass (pre- and post-grazing), botanical composition, soil cover, leaf area index, light interception, leaf angle, and concentrations of dry matter, organic matter, N, and in vitro digestible dry matter. When fertilized with 300 kg N ha−1 yr−1, leaf mass reached 18,560 kg ha−1. Leaf area index decreased with increasing stocking rate. The relationship between sward height and light interception was R2 = 0.0126. Increased stocking rate resulted in greater contribution of signalgrass [Brachiaria decumbens (Stapf.) R.D. Webster] in the botanical composition, with a contribution up to 29% in 2010. Elephantgrass nutritive value is directly affected by the fertilization levels and stocking rate, with highest nutrient concentrations observed with 2 AU ha−1 and 300 kg N ha−1 yr−1.(AU)


Subject(s)
Animals , Pennisetum/physiology , Fertilizers/analysis , Animal Feed/analysis , Brazil , Pasture , Nutritive Value
8.
Ciênc. rural (Online) ; 49(1): e20180324, 2019. tab
Article in English | LILACS | ID: biblio-1045236

ABSTRACT

ABSTRACT: The objective of this study was to evaluate the productive potential and mineral composition of the forage cactus IPA-Sertânia (Nopalea cochenillifera Salm Dyck). This species was analyzed both in monoculture and intercropped with leucaena [Leucaena leucocephala (Lam.) De Wit.] and gliricidia [Gliricidia sepium (Jacq. Steud.], and was assessed with different sources of manure (cattle, sheep, goat, and broiler litter) serving as fertilizer. The experiment was conducted at the Experimental Station of the Instituto Agronômico de Pernambuco in Caruaru, PE, Brazil. Treatments were allocated in a split-plot arrangement in a randomized complete block design, with four replications. Main plots consisted of cropping systems, while the split-plots were dedicated to manure sources. Cactus harvest was carried out after two years of regrowth. Response variables included both production and nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) concentrations. No differences were observed for cactus production between the cropping systems, with an average value of 22.1Mg dry matter ha-1 2 years-1. In the intercropped systems, greater proximity to the legumes increased the production of the cactus in the treatments with the cattle and sheep manure, and increased the concentrations of P, K, and Mg, but not of N. The introduction of tree legumes, along with the application of manure, contributes to an increase in production and nutrient concentration of IPA-Sertânia cactus.


RESUMO: Objetivou-se avaliar o potencial produtivo e a composição mineral da palma forrageira IPA-Sertânia (Nopalea cochenillifera Salm Dyck), em cultivo isolado e consorciada com leucena [Leucaena leucocephala (Lam.) de Wit.] ou gliricídia [Gliricidia sepium (Jacq.) Steud.], e adubada com as fontes de esterco bovino, ovino, caprino e cama de frango. O experimento foi conduzido na Estação Experimental do Instituto Agronômico de Pernambuco - IPA, em Caruaru. O delineamento foi casualizado em blocos, em parcelas subdivididas, com quatro repetições. As parcelas foram representadas pelos sistemas de cultivo e as subparcelas pelas fontes de esterco. A colheita da palma foi realizada aos dois anos de crescimento e analisada quanto à produção e aos teores de nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca) e magnésio (Mg). Não foram observadas diferenças de produção da palma entre os sistemas de cultivo, atingindo valor médio de 22,1t ha-1 2 anos-1 de matéria seca (MS). Nos sistemas consorciados, a maior proximidade com as leguminosas incrementou a produção da palma, nos tratamentos com os estercos bovino e ovino, e elevou os teores de P, K e Mg, mas não os teores de N. A introdução de leguminosas arbóreas, juntamente com a aplicação dos estercos, contribui para elevar a produção e os níveis de nutrientes da palma IPA-Sertânia.

9.
Acta sci., Anim. sci ; 33(2): 115-122, 2011. graf, tab
Article in Portuguese | VETINDEX | ID: biblio-1399599

ABSTRACT

O objetivo deste trabalho foi avaliar as características do pasto e da extrusa de novilhas Girolanda, submetidas a três taxas de lotação, em pastagem de capim Brachiaria decumbens Stapf., em diferentes períodos de avaliação. Foram utilizadas seis novilhas da raça Girolanda e os tratamentos foram constituídos por diferentes taxas de lotação (2, 4 e 6 UA); cada bloco foi formado por três piquetes. O delineamento foi de blocos ao acaso em parcelas subdivididas com medidas repetidas no tempo. A taxa de bocados dos animais variou com o período de avaliação, com valores de 41 bocados min.-1 (Período 1) e 33 bocados min.-1 (Período 3). A taxa de bocados reduziu ao longo dos períodos de pastejo com valores de 41 a 33 bocados min.-1 Já o tamanho do bocado apresentou valores maiores nos períodos de avaliação 2 e 3, na taxa de lotação 2 UA (0,40 e 0,43 g MS bocado-1). A matéria seca da extrusa apresentou valores maiores no 3° (15,0% de MS) e 2° (17,4% de MS) dia de pastejo. O aumento no teor de proteína bruta da extrusa ocorreu no terceiro período de pastejo (14,4%) e no teor de fibra em detergente neutro (75,3%).


The objective of this study was to evaluate the characteristics of the grass and extrusa from Girolanda heifers, under three stocking rates on grass pasture of Brachiaria decumbens Stapf., at different evaluation periods. Six Girolanda heifers were used, and treatments consisted of different stocking rates (2, 4 and 6 UA). Each block was formed by three paddocks. The design was a randomized blocks design in split-plot with repeated measures over time. The bite rate of the animals varied according to assessment period, with values of 41 bites min.-1 (Period 1) and 33 bites min.-1 (Period 3). Bite rate decreased over the grazing period, with values from 41 to 33 bit min-1. Bite size was larger in grazing periods 2 and 3, at the stocking rate of 2 UA (0.40 and 0.43 g DM bite-1). Extrusa dry matter was higher in the third (15.0% DM) and second (17.4% DM) days of grazing. An increase in crude protein content of extusa occurred in the third grazing period (14.4%) and for total neutral detergent fiber (75.3%).


Subject(s)
Animals , Cattle , Cattle , Pasture , Brachiaria
10.
Recife; IPA/UFRPE; 2010. 229 p. ilus, tab.
Monography in Portuguese | Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-1074194

Subject(s)
Pennisetum , Plants
11.
Acta sci., Anim. sci ; 31(3): 295-302, jul.-set. 2009. tab
Article in Portuguese | VETINDEX | ID: biblio-1459204

ABSTRACT

O trabalho teve como objetivo avaliar a produção, composição e o perfil de ácidos graxos do leite, parâmetros fisiológicos e atividades comportamentais de vacas da raça Pitangueiras, submetidas à condição de pastejo com e sem acesso à sombra. O ambiente foi monitorado diariamente em uma estação meteorológica. O delineamento experimental foi o inteiramente casualizado, sendo que 20 vacas em lactação foram divididas em piquetes nos tratamentos com e sem acesso à sombra. Não houve diferença (p > 0,05) entre os tratamentos quanto às variáveis fisiológicas, produção, composição e perfil de ácidos graxos do leite. Os animais com acesso à sombra buscaram o sombrite nos horários em que os índices de conforto térmico foram mais elevados. No turno da tarde os parâmetros fisiológicos foram mais elevados que no turno da manhã. O uso do sombrite foi favorável em relação ao ganho de peso dos bovinos leiteiros e perfil de ácidos graxos de cadeia longa, quando os índices de conforto térmico foram elevados. Nessas condições, sua utilização é recomendada para vacas da raça Pitangueiras em sistema de pastejo.


The objective of this trial was to analyze milk production, milk composition, fatty acid profile, physiological parameters, and behavior of Pitangueiras cows under grazing conditions and submitted to the presence or absence of shade in the paddock. The environment was monitored daily using a meteorological station at the research site. A complete randomized experimental design was used and 20 lactating cows were allocated in paddocks with or without shade. Daily milk productivity did not differ among cows. There was also no difference in the fatty acid profile and milk composition. Cows with shade available stayed under the shade during periods where thermal comfort index was greater. Physiological responses did not show significant differences; however, differences were observed between morning and afternoon periods, with greater values observed for the afternoon period. The use of artificial shade favored animal weight gain and long-chain fatty acid profile under high thermal comfort index. In this condition, the shade to Pitangueiras cows breed is advised.


Subject(s)
Animals , Cattle , Cattle/physiology , Milk/chemistry , Sunlight , Fatty Acids , Weight Gain/physiology , Pasture/methods
12.
Acta Sci. Anim. Sci. ; 31(3): 295-302, jul.-set. 2009. tab
Article in Portuguese | VETINDEX | ID: vti-3598

ABSTRACT

O trabalho teve como objetivo avaliar a produção, composição e o perfil de ácidos graxos do leite, parâmetros fisiológicos e atividades comportamentais de vacas da raça Pitangueiras, submetidas à condição de pastejo com e sem acesso à sombra. O ambiente foi monitorado diariamente em uma estação meteorológica. O delineamento experimental foi o inteiramente casualizado, sendo que 20 vacas em lactação foram divididas em piquetes nos tratamentos com e sem acesso à sombra. Não houve diferença (p > 0,05) entre os tratamentos quanto às variáveis fisiológicas, produção, composição e perfil de ácidos graxos do leite. Os animais com acesso à sombra buscaram o sombrite nos horários em que os índices de conforto térmico foram mais elevados. No turno da tarde os parâmetros fisiológicos foram mais elevados que no turno da manhã. O uso do sombrite foi favorável em relação ao ganho de peso dos bovinos leiteiros e perfil de ácidos graxos de cadeia longa, quando os índices de conforto térmico foram elevados. Nessas condições, sua utilização é recomendada para vacas da raça Pitangueiras em sistema de pastejo.(AU)


The objective of this trial was to analyze milk production, milk composition, fatty acid profile, physiological parameters, and behavior of Pitangueiras cows under grazing conditions and submitted to the presence or absence of shade in the paddock. The environment was monitored daily using a meteorological station at the research site. A complete randomized experimental design was used and 20 lactating cows were allocated in paddocks with or without shade. Daily milk productivity did not differ among cows. There was also no difference in the fatty acid profile and milk composition. Cows with shade available stayed under the shade during periods where thermal comfort index was greater. Physiological responses did not show significant differences; however, differences were observed between morning and afternoon periods, with greater values observed for the afternoon period. The use of artificial shade favored animal weight gain and long-chain fatty acid profile under high thermal comfort index. In this condition, the shade to Pitangueiras cows breed is advised.(AU)


Subject(s)
Animals , Cattle , Cattle/physiology , Sunlight , Fatty Acids , Milk/chemistry , Weight Gain/physiology , Pasture/methods
13.
Acta sci., Anim. sci ; 26(2): 251-257, 2004.
Article in Portuguese | VETINDEX | ID: vti-764434

ABSTRACT

The objective of this research was to select elephantgrass clones for grazing conditions. A randomized complete block design was used, with 16 treatments and four replications. Each plot had a total area of 25m2, with the presence of animals. The following parameters were determined: leaf blade accumulation rate (LBAR) above 40cm height and total, stem accumulation rate (SAR), total forage accumulation rate (TFAR), dry matter concentration (%DM), crude protein concentration (%CP) and, neutral detergent fiber (%NDF). The results showed significant difference (P<0.05) between clones and evaluation periods for LBAR above 40cm, total LBAR and TFAR, with mean values of 28.08, 41.62 and 49.18kg/ha/day, respectively. Crude protein and NDF differences (P<0.05) were also found between the clones for all the different parts of the analyzed plant. The forage lost presented a similar chemical composition to the leaf blades above 40cm and to the post-grazing residue. The clones CE-08-AD and Venezuela AD presented a high performance considering the evaluated parameters and may be considered as promising materials.


Objetivando selecionar clones de capim-elefante para utilização sob pastejo, realizou-se experimento num delineamento em blocos ao acaso, com quatro repetições e 16 tratamentos, no período de 15/07/99 a 19/04/00. Em parcelas com 25m2, foram estudados a taxa de acúmulo de lâminas foliares (LF) e de colmos (C), teores de matéria seca (MS), proteína bruta (PB) e fibra em detergente neutro (FDN). Houve diferença significativa (p<0,05) entre clones e períodos de avaliação para produção de LF acima de 40cm, produção total de LF e produção total de forragem, com valores médios de 28,08; 41,62 e 49,18kg/ha/dia, respectivamente. Os teores de PB e FDN também foram diferentes (p<0,05) entre os clones em todas as frações da forragem. A fração perdas de forragem apresentou qualidade semelhante às frações LF acima de 40cm de altura de resíduo pós-pastejo. Os clones CE-08-AD e Venezuela AD destacaram-se para a maioria dos parâmetros avaliados, mostrando-se promissores.

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