Food Habits of the Eastern and New England Cottontails

Dalke, Paul D.; Sime, Palmer R.

doi:10.2307/3795589

Cited by 37 publications

(18 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…**t-test indicates significant difference between groups at p<0.05. Sime, 1941;Dusi, 1952;Pehrson, 1981). It is hypothesized that muscle hypertrophy might be expected if experiments were carried out using a diet that requires more strenuous masticatory activity, since the response of skeletal muscle is dependent on the magnitude of the changes in activity.…”

Section: Discussionmentioning

confidence: 96%

Adaptations in the Temporalis Muscles of Rabbits after Masseter Muscle Removal

Guelinckx

Dechow²,

Vanrusselt³

et al. 1986

J Dent Res

View full text Add to dashboard Cite

Masseter muscles were surgically removed in six young female rabbits so that we could study adaptations of the superficial temporalis muscles (ST) to increased functional requirements. Eight weeks following surgery, we used morphological measurements, histochemistry, contractile properties in situ, and occlusal force in vivo to compare the muscles in the experimental animals and six control rabbits. Analysis of the results demonstrated a decrease in fatigability of ST after masseter myectomy. Incisal occlusal force decreased by 65% during the first two weeks, and no recovery was observed during the following six weeks. At eight weeks post-surgery, the mass, twitch tensions, and tetanic tensions of ST were not significantly different from those of the controls. An increase in the percent of the cross-sectional area composed of fast fatigue-resistant fibers, a slower time-to-peak twitch tension, and a decrease in fatigability suggest an increase in oxidative metabolism. Analysis of these results suggests that muscles used for highly repetitious activities with submaximal loadings adapt to increased functional requirements by increasing fatigue-resistant properties.

show abstract

Section: Discussionmentioning

confidence: 96%

Adaptations in the Temporalis Muscles of Rabbits after Masseter Muscle Removal

Guelinckx

Dechow²,

Vanrusselt³

et al. 1986

J Dent Res

View full text Add to dashboard Cite

show abstract

“…To understand how habitat fragmentation and predation affect populations of mammals, we have been investigating the demography of lagomorphs in the northeastern United States (Barbour and Litvaitis 1993;Brown and Litvaitis 1995;Villafuerte et al 1997). In this region, New England cottontails (Sylvilagus transitionalis) and eastern cottontails (Sylvilagus floridanus) occupy similar habitats (Eabry 1968;Probert and Litvaitis 1995) and utilize similar forage plants ( Dalke and Sime 1941). Yet these two species have responded differently to recent changes in landscape composition and predator abundance.…”

Section: Introductionmentioning

confidence: 99%

Foraging strategies of sympatric lagomorphs: implications for differential success in fragmented landscapes

Smith¹,

Litvaitis²

2000

Can. J. Zool.

View full text Add to dashboard Cite

In recent decades, the distribution of New England cottontails (Sylvilagus transitionalis) has declined substantially in response to forest maturation and fragmentation. Populations of eastern cottontails (Sylvilagus floridanus) have expanded into the range of S. transitionalis, since they are apparently less affected by the consequences of habitat modifications. We suspected that S. floridanus was able to exploit small patches of habitat where S. transitionalis was vulnerable to intense predation and we evaluated this explanation using large enclosures within which we manipulated the quality and distribution of food in relation to escape cover. In trials with low-quality food in cover and high-quality food in open areas, S. transitionalis sacrificed food quality for safety by remaining in close proximity to cover. Sylvilagus floridanus avoided low-quality food in cover and foraged at sites containing high-quality food away from cover. When food was removed from cover, S. transitionalis was reluctant to forage in the open and lost a greater proportion of body mass and succumbed to higher rates of predation than did S. floridanus. We applied these results to patterns of foraging by free-ranging rabbits in a fragmented landscape and estimated that S. transitionalis could successfully exploit only 32% of the available habitat without experiencing elevated rates of predation, whereas S. floridanus could exploit 99% of the habitat. Thus, the consequences of habitat fragmentation (especially higher predation risk) may not be as detrimental to S. floridanus, and this species will likely persist, whereas populations of S. transitionalis will continue to decline.Résumé : Au cours des dernières décennies, la répartition du Lapin de Nouvelle-Angleterre (Sylvilagus transitionalis) s'est rétrécie considérablement à la suite de la maturation et de la fragmentation des forêts. Les populations du Lapin à queue blanche (Sylvilagus floridanus), visiblement moins sensibles aux modifications de l'habitat, sont venues envahir l'espace évacué par S. transitionalis. Nous soupçonnions au départ que S. floridanus serait capable d'exploiter les petites zones de l'habitat où S. transitionalis s'est révélé très vulnérable à la prédation intensive; nous avons évalué cette prédiction au moyen de grands enclos dans lesquels nous avons manipulé la qualité et la répartition de la nourriture en relation avec les zones de refuge. Au cours des expériences avec de la nourriture de mauvaise qualité dans les zones de refuge et de nourriture de bonne qualité en milieu ouvert, S. transitionalis préférait sacrifier la qualité de la nourriture pour s'assurer la sécurité reliée à la proximité d'un refuge. Sylvilagus floridanus évitait la nourriture de mauvaise qualité des zones de refuge et préférait gagner les sites plus éloignés, en milieu ouvert, où il y avait de la nourriture de qualité. Au retrait complet de la nourriture dans les zones de refuge, S. transitionalis ne s'aventuraient pas en terrain ouvert; ils ont perdu une forte proportion de leur mas...

show abstract

“…californicus;Hewson, 1962, for Lepus timidus; Pease et al, 1979, for L . americanus;Dalke and Sime, 1941;and Dusi, 1952, for S. floridanus). It is further known that juvenile animals in particular prefer young shoots and other tender, succulent parts of plants as food (Bailey, 1969;Turcek, 1959).…”

Section: Functional Significance Of Morphological Changementioning

confidence: 99%

Jaw movements and muscle activity during mastication in growing rabbits

1989

View full text Add to dashboard Cite

To investigate the biomechanical effects of juvenile growth changes in the rabbit masticatory apparatus a comparison was made of mastication in just-weaned and adult animals. Mandibular movements in two planes were registered by cineradiography. Masticatory muscle activity was recorded by fine-wire electromyography. The same pattern of unilateral mastication was present in the two ages. The most important changes in the jaw movements are 1) a decrease of jaw opening speed and chewing frequency and an increase in jaw opening time, 2) a decrease in maximum gape in soft food and an unaltered gape in small-particle hard food, and 3) an increase in lateral jaw excursion, mainly due to a more pronounced movement of the jaw to the balancing side (lingual phase). The contraction patterns were basically similar in the two ages. The higher chewing frequency in young animals was attained by a larger degree of overlap between opening and closing muscle activities. Young animals used relatively more EMG activity to chew hay, the hardest food. The changes in opening speed, gape, and chewing frequency are consistent with earlier predictions from the morphological changes, and so is the extra activity needed to chew hard food. The increase in lateral excursion was not predicted. It is suggested to be caused by cheek teeth wear, making possible smooth occlusal guidance of the jaw at the balancing side. Some of the changes in juvenile morphology can be viewed as adaptations to a changing diet.

show abstract

Food Habits of the Eastern and New England Cottontails

Cited by 37 publications

References 4 publications

Adaptations in the Temporalis Muscles of Rabbits after Masseter Muscle Removal

Adaptations in the Temporalis Muscles of Rabbits after Masseter Muscle Removal

Foraging strategies of sympatric lagomorphs: implications for differential success in fragmented landscapes

Jaw movements and muscle activity during mastication in growing rabbits

Contact Info

Product

Resources

About