27 research outputs found
Role of livestock in human nutrition and health for poverty reduction in developing countries
Livestock keeping is critical for many of the poor in the developing world, often contributing to multiple livelihood objectives and offering pathways out of poverty. Livestock keeping also affects an indispensable asset of the poor, their human capital, through its impact on their own nutrition and health. This paper outlines the linkages between livestock keeping and the physical well-being of the poor, and examines a number of commonly held beliefs that misrepresent livestock development issues related to these linkages. These beliefs limit the scope of intervention programs to promote livestock and limit their potential contribution to poverty reduction. Recognition of the complexity of the role livestock play in household decision-making and of the opportunities foregone due to these misconceptions can enhance the ability of livestock to contribute to human well-being in the developing world
Body condition score, weight variation and reproductive performance of beef cows in rangelands from the Pantanal region
Objetivou-se avaliar a influência do escore de condição corporal (ECC) sobre a eficiência reprodutiva de vacas de cria nos períodos pré e pós-parto e a probabilidade de parição, usando o escore de condição corporal e a variação ponderal no período crítico do ciclo reprodutivo. Utilizaram-se 248 vacas multíparas mantidas em pastagens nativas distribuídas em quatro estratégias de suplementação: mistura mineral (controle); suplemento farelado; suplemento líquido; suplemento líquido para vacas e bezerros. As avaliações de peso e ECC, na escala de 1 a 9, foram realizadas no período crítico: em agosto (período pré-parto, 60-90 dias antes da parição) e em janeiro (período pós-parto e reprodutivo) durante quatro anos consecutivos. Para a análise dos anos consecutivos de reprodução, criou-se um escore de reprodução, ou seja, somou-se o número de parições de cada vaca durante os quatro anos pecuários avaliados. O escore de condição corporal nos períodos pré e pós-parto e a idade da vaca influenciaram o escore de reprodução. Portanto, para avaliação da probabilidade de parição, foram utilizadas todas as vacas, classificadas em paridas e vazias. Utilizando equações de estimação generalizadas (EEG), foi modelada a probabilidade de as matrizes serem classificadas como paridas considerando variáveis exploratórias ao longo do tempo. Para se obter probabilidade de parição superior a 80%, as vacas devem possuir escore de aproximadamente 5,5 no período pré-parto. Aproximadamente 60% das vacas paridas mantiveram ou ganharam peso no período crítico do ano, o que levou a maior probabilidade de reconcepção, similar ao observado para as vacas vazias, porém com probabilidade menor de parição. O período pré-parto é o melhor para estimar a probabilidade de parição das vacas por meio da avaliação do escore corporal. A seleção de vacas adaptadas às condições bioclimáticas do Pantanal aumenta a probabilidade de produção de um bezerro por vaca por ano. _________________________________________________________________________________ ABSTRACTThe aim of this study was to evaluate the influence of body condition score (BCS) on reproductive performance of beef cows before and after calving and to evaluate the calving probability using body condition score and weight variation during critical periods of the cow reproductive cycle. From 2001 to 2005, the body condition score was recorded in 248 multiparous cows raised in native pastures, submitted to different supplementation treatments (mineral mixture only - control; dry supplement; liquid supplement and liquid supplement for cow and calves). Weighing and body condition evaluation were made on a 1-9 point scale in August (prepartum period, 60-90 days before parturition) and January (postpartum and reproductive period). A reproduction score was created in function of the body scores in four consecutive years. Except for the treatment, the other factors (body condition score in the prepartum and postpartum periods and cow age) influenced the reproduction score. Thus, the calving probabilities were estimated for all cows. Generalized estimating equations (GEE) were used to evaluate the calving probability in function of the exploratory variables over time. Calving probability higher than 80% was obtained when cows scored 5,5 before calving. In relation to weight, the results showed that about 60% of calving cows maintained or gained weight in the postpartum period, leading to increase in the rebreeding probability. Similar situation occurred with single cows; however, the calving probability was lower. These results indicate that the calving probability using BCS is better estimated before calving. Furthermore, it indicates the presence of cows more adapted to the Pantanal climatic and feeding conditions than others
Quality of the forage apparently consumed by beef calves in natural grassland under fertilization and oversown with cool season forage species
The objective of this study was to evaluate the chemical composition of the forage apparently consumed by steers in a natural grassland on region of Campanha, in Rio Grande do Sul, Brazil, subjected or not to different inputs: NP - natural pasture without inputs; FNP - fertilized natural pasture and INP - improved natural grassland with fertilization and over-seeded with cultivated winter species. Three Angus steers testers and a variable number of regulator animals per experimental unit were utilized in order to maintain 13 kg of DM/100 kg of live weight (LW) as forage allowance. One time at each season, hand plucking samples were performed along the daily grazing time simulating forage harvested by the animals. The collected samples after drying and grind were submitted to chemical analysis to determine the forage quality. Except in winter and spring, the values of neutral detergent fiber were higher than the critical value of 550 g/kg of DM, which could limit forage intake, demonstrating that the values of forage on offer provided (15.6; 13.7; 13.5; 15.8 kg of DM/100 kg of LW/day in summer, autumn, winter and spring, respectively) were not restrictive to intake. The oversowing of winter cultivated species or fertilization positively alter the degradable fiber content. The seasons had marked influence on the chemical composition of forage apparently consumed; positively increasing some fractions of forage chemical composition in the seasons in which native or cultivated winter species increased their participation. The forage chemical composition is the determining factor in animal performance in natural pasture
Avaliação de três cultivares de Panicum maximum Jacq. sob pastejo: comportamento ingestivo de bovinos
Comportamento ingestivo de ovelhas e cordeiras em pastagem de azevém-anual sob níveis crescentes de suplementação
Intervalo e intensidade de desfolhação nas taxas de crescimento, senescência e desfolhação e no equilíbrio de gramíneas em associação Interval and intensity of defoliation on the growth, senescence and defoliation fluxes and equilibrium of associated grasses
O experimento foi realizado no INRA (Institut National de la Recherche Agronomique) em Theix, França. Duas gramíneas (azevém perene e festuca)foram semeadas em caixas (0,13 m²) e submetidas a três intervalos (3,5, 7 e 14 dias) e três intensidades (160, 320 e 640 bocados.m-2 a cada desfolhação) de desfolhação, com quatro repetições por tratamento. Quatro meses após a semeadura, a cada data de desfolhação, as caixas foram oferecidas, individualmente, a quatro ovelhas secas e retiradas após a realização de um determinado número de bocados. Para cada gramínea foram estudadas as taxas de crescimento, senescência e desfolhação. Os resultados mostraram que o intervalo e a intensidade de desfolhação tiveram efeitos diferenciados nas taxas de crescimento, senescência e desfolhação e no equilíbrio da associação.<br>The experiment was carried in INRA (Institut National de la Recherche Agronomique) at Theix, France. Two grasses (perennial ryegrass and tall fescue) were grown in sward boxes (0,13 m²) and submitted to three defoliation intervals (3,5, 7 and 14 days between two successive defoliation) and three defoliation intensities (160, 320 and 640 bites.m-2 at each defoliation). Four months after sowing, at defoliation date, sward boxes were offered to four individual dry ewes and removed after a given number of bites had been taken. For each grass species, the growth, senescence and defoliation fluxes were studied. The results showed that the interval and the intensity of grazing had distinct effects on the growth, senescence and defoliation fluxes as well as on the equilibrium of grass mixtures