On the anatomy of vertebrates

Owen, Richard

doi:10.5962/bhl.title.33654

Cited by 126 publications

(92 citation statements)

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“…Knox (1831), McIntosh ('30) and De la Vega ('50) observed that the groove was defined by two lips. However, Cuvier (1805), Brandt (1841), Mayer (1844), Colin (1854), Owen (1868), Cordier (1894), and Bohlken ('60) described only a single lip. Similarly in the camel, some authors (Boas, 1890;Hegazi, '50) described two lips, while others (Lesbre, '03;Colin, 1854) recognized a single lip.…”

Section: Discussionmentioning

confidence: 99%

A gross study of the compartmentalized stomach of two new‐world camelids, the llama and guanaco

Vallenas

Cummings

Munnell

1971

Journal of Morphology

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The llama and guanaco stomach consisted of three compartments. A transverse pillar divided the large, first compartment into cranial and caudal sacs. Both sacs contained recessed glandular saccules. The saccules in the caudal sac were everted during the gastric contraction cycle. The non-recessed surfaces of this compartment were covered by stratified squamous epithelium.The first compartment communicated on the right with a smaller, reniform second compartment. Except on the lesser curvature, this compartment contained deep cells which were lined by a papillated glandular mucosa.The ventricular groove, defined by a single muscular lip, coursed along the cranial sac of the first compartment, over the lesser curvature of the second compartment, and terminated at the tubular passage to the third compartment.The initial four-fifths of the elongate third compartment contained mucigenous glands like those found in the saccules and cells of the first and second compartment. Proper gastric glands and pyloric glands were confined to the terminal one-fifth of the third compartment.Attempts to homologize the compartments of the camelid stomach with those of the Pecora or so-called advanced ruminants were unsuccessful. The results of this study and concurrent physiologic investigations indicated that the processes of ruminant digestion can operate within wide anatomic boundaries, and that the camelid stomach with its extensive glandular mucosa is adapted for greater digestive efficiency than the advanced ruminant stomach.The new-world camelids, the llama, alpaca, guanaco, and vicuna are part of the livestock economy of South America. These animals live in a n extensive Andean zone, often at 14 to 18,000 feet above sea level. Here, the pastures consist of fibrous and woody grasses. The camelids effectively utilize this poor quality roughage at altitudes where cattle and sheep cannot graze.The camelids, like our domestic ruminants, have a capacious, compartmentalized stomach and they are ruminating animals. Structurally, however, the camelid stomach differs from that of our domestic ruminants. Attempts to homologize the compartments of the camelid stomach with those of the other ruminants have lead to considerable controversy. This controversy has contributed to the larger problem of the proper taxonomic status of the Tylopoda, i.e. the new and old-world camelids, relative to the Pecora or the so-called ad-J. MORPH., 234: 399-424.vanced (Romer, '68) or true ruminants (Walker, '64).Perrault (1666-1699) originally described four compartments in the stomach of the camel and dromedary, and noted that the mucosa in these compartments differed from that observed in other ruminating animals. In the first and largest compartment (A, figs. 1-3), he described two areas of sacculations, each of which formed a series of swellings on the serosal surface.The smaller second compartment (B, figs. 2, 3), h e noted, contained numerous deep pouches. Perrault suggested that these pouches constituted the water reservoirs previously mentio...

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Section: Discussionmentioning

confidence: 99%

A gross study of the compartmentalized stomach of two new‐world camelids, the llama and guanaco

Vallenas

Cummings

Munnell

1971

Journal of Morphology

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“…This suggests that fluid digesta, solutes and very fine particles are selectively retained in the gastrointestinal tract relative to large particulate digesta. The site of selective retention is the enormous caecum and proximal colon of the Koala (Cork & Warner 1983), described by Owen (1868) as the largest of any mammal. Selective retention of solutes, bacteria and other small particles in the hindgut concentrates digestive effort on the potentially most digestible components of the digesta leaving the small intestine, and reduces loss of microbial protein in the faeces.…”

Section: Introductionmentioning

confidence: 99%

A flexible digestive strategy accommodates the nutritional demands of reproduction in a free‐living folivore, the Koala (Phascolarctos cinereus)

Krockenberger

Hume

2007

Functional Ecology

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Summary1. Small mammalian folivores, such as the koala, are considered to be energetically limited by their relatively small gut capacity compared with metabolic requirements and the gut-filling effect of their poorly digestible leaf diet. However, during peak lactation, female koalas increase their food intake (35%) to meet the nutritional demands of reproduction. 2. This study examines mechanisms by which reproductive female koalas overcome limitations to food intake. 3. Digesta retention in the gastrointestinal tract was measured in free-living koalas using inert solute (cobalt (Co) complexed with EDTA) and particle markers (chromium (Cr)-mordanted to cell wall constituents' 600-1180 µ m in diameter). 4. The whole gut rate of passage of both markers was 2-3 times faster than in captive koalas, probably because of 35%-69% greater food intakes in the wild. As in captive koalas, the solute marker was retained longer than the particle marker in free-living animals, indicating selective retention of fluid, solutes and small particles (including bacteria) in the hindgut caecum and proximal colon.The digesta retention of both markers were unaffected by the 35% increase in food intake associated with reproduction, largely due to a 42% increase in the solute marker pool size in lactating animals. The pool size of large particles in the digesta was unchanged. 5. Thus, female koalas meet the nutritional demands of reproduction at least partly by an increased solute digesta pool size, minimizing the detrimental effects of increased food intake on digestion of solutes and small particles, and on faecal loss of microbial protein. There was some indication that they also increase the passage rate of large particles or increase the efficiency of separation of large and small particles to reduce the gut-filling effects of large, poorly digestible particles. 6. Clearly the digestive strategy of the koala is more flexible, and limitations to food intake less stringent, than previously thought. Female koalas accommodate the increased food intake required to meet the demands of free-living and reproduction without compromising nutrient extraction from their eucalypt leaf diet. We suggest that similar flexibility in digestive strategy is likely to play an important role in the way that most small mammalian herbivores, especially arboreal folivores, meet the nutritional demands of reproduction.

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“…Three categories of IBs were recognized, namely epineural, epipleural, and epicentral (Owen, 1866). There has been a debate had three categories of IBs.…”

Section: Discussionmentioning

confidence: 99%

“…Almost all species of cyprinids have IBs. According to the position of attachment in fish muscle, IBs have been subdivided into three categories, namely epineural, epicentral, and epipleural (Owen, 1866). Epineurals are those IBs attached proximally to the neural arches above the horizontal septum, whereas epipleurals are attached to the hemal arches or the ribs that lie below the horizontal septum.…”

mentioning

confidence: 99%

“…Epineurals are those IBs attached proximally to the neural arches above the horizontal septum, whereas epipleurals are attached to the hemal arches or the ribs that lie below the horizontal septum. Epicentrals attach to the central vertebrae in the plane of the horizontal septum (Owen, 1866). The IBs are of variable occurrence; for instance, in some teleosts, only epineurals and epipleurals are present, and in some Perciformes, IBs have completely disappeared (Patterson & Johnson, 1995).…”

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confidence: 99%

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Evolution of the intermuscular bones in the Cyprinidae (Pisces) from a phylogenetic perspective

Yang

Jiang

Wang

et al. 2019

Ecology and Evolution

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Intermuscular bones (IBs) are widely present in morphologically generalized teleost fishes and are commonly found in the Cyprinidae. Intermuscular bones are small, hard spicules of bone that are formed by ossification in the myosepta between neighboring myomeres. Why fish have IBs, and whether there is any evolutionary pattern to their occurrence, has been poorly understood. However, the presence of IBs does substantially affect the meat quality and commercial values of many cyprinid fishes in aquaculture. In this study, we sampled 592 individuals of cyprinid fishes to systematically investigate the evolution of IBs from a phylogenetic point of view. We found that the total number of IBs in the Cyprinidae ranged from 73 to 169, and we clarified that only two categories of IBs (epineural and epipleural) were present in all examined cyprinids. Most of the IBs were distributed in the posterior region of the fish, which might be an optimal target for selecting fewer IB strains in aquaculture. There was a positive correlation between IBs and the number of vertebrae, thus making it possible to predict the approximate number of IBs by counting the number of vertebrae. Although the IBs displayed some correlation with phylogenetic relationships in some lineages and to ecological factors such as diet (especially carnivore), in an overall view the variations of IBs in cyprinids were extremely diverse. The number and patterns of IBs in these fishes may reflect their phylogenetic history, but have been shaped by multiple environment factors. In this study, we also confirmed that X‐ray photography remains an optimal and reliable method for the study of IBs.

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On the anatomy of vertebrates

Cited by 126 publications

References 0 publications

A gross study of the compartmentalized stomach of two new‐world camelids, the llama and guanaco

A gross study of the compartmentalized stomach of two new‐world camelids, the llama and guanaco

A flexible digestive strategy accommodates the nutritional demands of reproduction in a free‐living folivore, the Koala (Phascolarctos cinereus)

Evolution of the intermuscular bones in the Cyprinidae (Pisces) from a phylogenetic perspective

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