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Evaluation of Physical and Behavioral Traits of Llamas (Lama glama) Associated with Aggressiveness Toward Sheep-Threatening CanidsCavalcanti, Sandra M. C. 01 May 1997 (has links)
Canid predation poses a serious threat to the sheep industry in the United States. Llamas are becoming popular among livestock producers as part of their predation management programs but there is little information on the factors associated with llama guarding behavior. This study examined several physical and behavioral attributes of individual llamas to assess whether they might predict the aggressiveness llamas display coward canids. The study was conducted in three phases. The first involved determining some physical and behavioral traits of individual llamas. Twenty individuals were randomly assigned to one of four groups (n = 5/group) and frequencies with which animals initiated and responded to various behaviors, e.g., dominance, aggression, threats, subordination, leadership, and alertness, were documented using focal-group sampling. Individuals were then ranked according to the frequency with which they displayed each behavior. In the second phase, activity patterns of individual llamas with sheep were assessed. Lamas varied in how close to sheep they stayed (mean = 48.2 m I 3.5) as we 1 as in the way they distributed their activities. The third phase examined interactions among llamas, sheep, and a domestic sheep dog to assess their individual aggressiveness toward canids.
Llamas varied in the degree of aggressiveness displayed toward the dog; some chased the dog, others ran from it, some stayed with the flock, and others did not. Llamas were ranked based on these responses. Llamas with top ranks were curious and chased the dog, but stayed close to the sheep. Bottom-ranked individuals ignored the sheep and ran from the dog. Physical and behavioral traits of llamas and their behavioral patterns with sheep were then compared with aggressiveness they displayed toward the dog. Leadership and alert behaviors were correlated with aggressiveness (r = 0.472, p = 0.064 and r = 0.607, p = 0.012, respectively) Weight of llamas was also correlated with aggressiveness (r = 0.475, p = 0.039). Llama coloration was associated with aggressiveness they displayed toward the dog (X2 = 6.003, df = 2, p = 0.049), however, color was also associated with the weight of llamas (X2 = 7.49, df = 2, p = 0.024). Traits correlated with llama aggressiveness are easily recognized and sheep producers interested in acquiring a llama should consider them when selecting livestock guardians.
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Evidências de atividade da via metabólica da frutose em neonatos bovinos derivados de embriões produzidos in vitro e in vivo e seu efeito no período neonatal imediato / Evidence of the frutose metabolic pathway activity and its effects on the immediate neonatal period of in vivo and in vitro derived newborn calvesSchütz, Luís Fernando 27 March 2012 (has links)
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Previous issue date: 2012-03-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Newborn calves derived from in vitro fertilization (IVF) procedures often have
difficulties to adapt to life ex utero, with high birth weights usually associated with high
plasma fructose levels in some in vitro-produced calves. We hypothesize that the fructose
metabolic pathway is active at birth, with the fructosemia levels being either detrimental or
beneficial to animal survival depending on the respiratory function in the neonate. To
investigate this hypothesis, four and five newborn calves derived from in vitro- and in
vivo-produced embryos were evaluated for morpho-physiological and clinical normality at
birth, and for subsequent signs adaptation to life ex utero in the first 24 h of life. At birth,
animals were subjected to gene expression analyses for key enzymes in the fructose
metabolic pathway and to the collection of fetal fluids and urine for fructose analysis. In
addition, during the period between birth and 24 h of life, animals were evaluated for
clinical signs, plasma concentrations of metabolic substrates, blood chemistry,
hemogasometry, and hematologic parameters. Neonatal physical, clinical, and behavioral
traits were compared with physiological, biochemical, metabolic, and molecular findings
observed at birth and in the first 24 h of life for the determination of physiological
alterations and relationships of biological significance between the experimental groups. In
vitro-derived newborn calves were heavier and larger at birth, having lower respiratory rate
and thermoregulatory response than in vivo-derived controls, with no significant
differences in fructose, glucose and lactate levels between groups. Nevertheless,
physiological and metabolic findings at birth, in general, were widely similar and normal
between groups. However, during the first 24 h of life, IVF-derived calves showed
physiological, metabolic, biochemical, hemogasometric, and hematologic features
indicative of a lower adaptation to life ex utero, particularly in the first 4 to 6 h of life. The
main differences indicated that larger animals, mainly the IVF-derived calves, had more
difficulties to maintain plasma oxygen levels, likely due to a less efficient hematosis, with
evidence of a metabolic shift and elevation of metabolic substrates (mostly lactate), and a
trend for acidosis followed by a compensatory normalization of the acid-base balance,
predominantly in the first 6 h of life. The physiological and metabolic role of fructose was
apparent, but not conclusive / Neonatos bovinos derivados de fecundação in vitro (FIV) frequentemente
apresentam dificuldades de adaptação à vida ex utero, estando o excesso de peso ao nascer
associado a elevadas concentrações plasmáticas de frutose em alguns bezerros de FIV. A
hipótese deste trabalho é que a via metabólica da frutose é ativa ao nascimento, podendo
ser benéfica ou prejudicial à sobrevivência neonatal, dependendo da função respiratória do
neonato. Para investigar esta hipótese, quatro neonatos bovinos derivados de embriões
produzidos in vitro e cinco de embriões in vivo foram avaliados quanto à normalidade
morfo-fisiológica e clínica ao nascimento, e quanto a sinais de adaptação ao ambiente
extrauterino nas primeiras 24 h de vida. Ao nascimento, os animais foram submetidos à
análise de expressão gênica de enzimas da via metabólica da frutose e à coleta de fluídos
fetais e de urina para mensuração da frutose. Durante o período do parto até as 24 h de
vida, foram avaliados os sinais clínicos, as concentrações plasmáticas de substratos
metabólicos, a bioquímica sanguínea, a hemogasometria e o hemograma. As características
físicas, clínicas e comportamentais dos neonatos foram comparadas aos parâmetros
fisiológicos, bioquímicos, metabólicos e moleculares avaliados ao parto e nas primeiras 24
h de vida para a determinação de alterações fisiológicas e inter-relações de significância
biológica entre os grupos experimentais. Os neonatos bovinos derivados de FIV foram
mais pesados e maiores ao nascimento, apresentando uma menor frequência respiratória e
uma menor resposta termoregulatória que animais SOV, não havendo diferenças nos níveis
de frutose, glicose e lactato entre os grupos. Não obstante, os parâmetros fisiológicos e
metabólicos ao nascimento foram, em geral, amplamente similares e normais entre os
grupos experimentais. Porém, ao longo das primeiras 24 h, os neonatos de FIV
apresentaram características fisiológicas, metabólicas, bioquímicas, hemogasométricas, e
hematológicas indicativas de uma maior dificuldade de adaptação à vida ex utero, em
especial nas primeiras 4 a 6 h após de vida. As principais diferenças indicaram que animais
maiores, em especial os de FIV, apresentaram maior dificuldade para a manutenção da
normóxia, por uma hematose menos eficiente, mudanças metabólicas e uma elevação de
substratos metabólicos (principalmente o lactato), e uma tendência à acidose com
normalização compensatória do balanço ácido-base, principalmente nas primeiras 6 h de
vida. O papel fisiológico e metabólico da frutose foi aparente, mas não conclusivo
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