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1.
Captive and wild African elephants frequently suffer tusk fractures. Several institutions shorten the tusks of captive elephants to reduce fractures and injury as a result of behaviour within enclosures. Fracturing or coronal amputations that expose pulp lead to pain for the elephant. Estimating coronal pulp lengths may thus help to minimise the risk of pulp exposure during amputations. We aimed to determine the length of the pulp beyond the lip margin from an external tusk characteristic. Tusks collected from elephants in Namibia and the Kruger National Park had similar morphological relationships. This statistical property allowed us to correct for missing data in our data sets. Pulp volume and pulp length correlated with tusk circumference at the lip. Even so, the circumference at the lip could not predict the length of the pulp in the crown external to the lip. Our findings suggest that tusks, irrespective of sex or age, amputated further than 300 mm from the lip should not expose pulp.  相似文献   

2.
The incidence of tusklessness varies between free-ranging African elephant populations. Sex-linked genetic drift predicts 2 outcomes--the condition becomes fixed and sex-specific incidences diverge when populations are small and/or heavily poached. By contrast, for large and intact populations, tusklessness diminishes and there is no variation between sexes. We tested these predictions by comparing sex-specific incidences between 15 populations: a small one with a skewed founder effect towards tusklessness; 5 that had experienced intense levels of poaching; 2 that had been subjected to non-selective culling and 7 that are relatively pristine. Patterns of rainfall were studied of tusk fractures amongst these populations to correct for any effect that acquired tusklessness may have on our predictions. The incidence of tusk fractures was related to annual rainfall, but the mechanism that leads to an increase of the condition in drier areas was not clear Incidences of tusk fractures in free-ranging populations implied that the frequency of acquired bilateral tusklessness is low and should not affect our results. All males had tusks. Tusklessness in females was high in the small skewed founder population and some of those where there was a history of poaching. The incidence is expected to decline if the residual population is large.  相似文献   

3.
4.
Armadillos are ancient mammals important as models for biomedical, evolutive and ecological studies, because they have adaptive and primitive morpho-physiological characteristics. In this work we study the splenic microarchitecture of the 'Patagonian Piche', Zaedyus pichiy, as an attempt to understand the relationship between the organizational plan of the organ and the particular features of this species. The organ samples were classically processed for light and electron microscopic study. The microanatomy of the organ as well as its different cell types are studied. The spleen is non-sinusoidal, with the typical arrangement for storage functions. White pulp is well defined. Red pulp is a meshwork of circulating, immunocompetent and haemopoietic cells. The general structure of the organ agrees with the semi-fossorial habit and the adaptability of the species. Comparative aspects with other armadillos or other less specialized groups are discussed. Persistence of haemopoietic spleen activity in the adult suggests the existence of specific inductive functions of the stroma. Better knowledge of spleen structure and function in ancient mammals may give important information about their phylogeny.  相似文献   

5.
Elephant tusk removal usually requires costly surgical procedures that are time-consuming and present a significant risk to the animal when performed using general anesthesia. Such techniques require gauges, chisels, and forceps to remove the tusk. This article reports the simple removal of the tusk of an 18-yr-old African elephant (Loxodonta africana) without the use of surgical instruments and anesthesia. Rubber elastics were placed around a tusk, causing loss of alveolar bone with subsequent exfoliation of the tusk within 3 wk. The healing process was uneventful.  相似文献   

6.
There are many species classified as ungulates that possess a large variety of dental formulae and dental adaptations. Despite the diversity found within the ungulate group, the list of dental abnormalities remains short. Regardless of the contributing factors, cases of aveolitis accompanied by osteomyelitis ("lumpy jaw") occur more frequently than some of the other dental problems that are encountered in these species (fractures of tusks/canines, malocclusion, eruption cysts). Commonly, treatment of "lumpy jaw" requires exodontia with additional antibiotic therapy using a drug that is appropriate for the type of infection and the species of animal. Regardless of the dental abnormality, anesthetic, diagnostic, and treatment considerations typically provide the greatest challenge to the clinician in these cases.  相似文献   

7.
An 18-year-old African elephant was determined to have a nonrepairable crack in its left tusk. Treatment included extraction of the tusk, using rotational and extractional forces, and administration of antibiotics, followed by 1 year of flushing the opened tusk cavity with warm tap water. Two years after surgery, the elephant was healthy, and the tusk cavity was 80% filled with normal tissue.  相似文献   

8.
A preliminary observational study was conducted to evaluate the animal welfare impacts of holding and mixing on boars; specifically, the need to tusk trim on arrival at assembly. Cull boars assembled in Manitoba from 3 western Canadian provinces were observed without intervention. Although aggression among boars was common, significant physical injury to boars from handling and other boars was rare. Tusk trimming was widely practised in mature boars prior to transport in the population studied. Length of time assembled, number of boars in a pen, temperature, size of boar, and presence of tusk were not associated with change in the skin score of new boars introduced into a pen. Holding groups of previously unfamiliar boars en route to slaughter did not appear to be a significant risk for increased skin lesions in the population studied. Further research is required into the methods and welfare implications to boars subjected to tusk trimming.  相似文献   

9.
It is imperative that the veterinarian treating exotic companion mammals stay abreast of the latest developments relating to medications and drug delivery approaches for safety and efficacy. Sustained-release formulations of commonly used drugs, as well as newer routes for administration of therapeutic agents, allow the veterinarian treating exotic companion mammals to reduce the stress associated with drug administration. Interactions can occur between vehicle and drugs when formulations are compounded; therefore, research studies are warranted regarding potential problems associated with these formulations. However, newer studies have been published that provide the basis for exploring the use of different vehicles, frequency of dosing, and drug delivery techniques for various classes of drugs in exotic mammals. The goals of this review are to not only evaluate new medications or uses for medications in companion exotic mammal patients but also review new methods of drug delivery that might be useful to the veterinarian who treats these animals.  相似文献   

10.
Small mammals are frequently presented to the veterinary surgeon for skin disorders as children's pets, laboratory animals or commercial breeding groups. The role of the veterinary surgeon in these different categories is examined. Investigation and management of these disorders is discussed placing particular emphasis on a diagnostic approach and highlighting those areas which differ from canine and feline dermatology. Common dermatoses of these animals are described on an aetiological basis.  相似文献   

11.
A 31-year-old captive male African elephant (Loxodonta africana) of 5,000-kg body weight died suddenly in ventral recumbency. Lesions seen at necropsy were bilateral purulent pulpitis and periodontitis of both tusks, serous atrophy of coronary groove fat, Grammocephalus cholangitis, myocardial and skeletal lipofuscinosis, and scattered segmental necrosis in the pectoral muscles. Nonhemolytic streptococci, Corynebacterium sp, Peptostreptococcus anaerobius, Fusobacterium nucleatum, and Bacteroides sp, were recovered from the exudate around one or both tusks. We postulated that the elephant died of hypoxia from prolonged ventral recumbency because of weakness and inability to rise secondary to toxemia from bilateral pulpitis and periodontitis.  相似文献   

12.
1. Ultrastructural changes that take place in the spermatids of the turkey were studied. Twelve steps of spermiogenesis are described. 2. Acrosomal formation is similar to that in the domestic fowl and quail. The perforatorium develops as a dense granule in a tubular invagination of the thickened part of the nuclear membrane during the acrosomal phase of spermatid development. 3. Patchy appearances of the circular (CM) and longitudinal (LM) manchette occur concurrently for a very brief period before the complete disappearance of the former and full establishment of the latter, an indication that the CM reorganises to become the LM. 4. A chromatoid body, as found in mammals, is present in the mid-piece of the turkey spermatid, and glycogen aggregations occur in the spermatid cytoplasm, but not in the mature spermatid or spermatozoon. 5. Mitochondrial alignment around the axoneme in the mid-piece takes place only after the dissolution of the LM, unlike in the Japanese quail. 6. The merits and disadvantages of the 4-phase and step-wise systems of spermatid classification and evaluation are discussed.  相似文献   

13.
柑橘渣在动物生产中的应用研究   总被引:4,自引:0,他引:4  
柑橘渣是柑橘加工业的主要副产物,约占鲜重的45% ̄60%,是优良的反刍动物饲料,在单胃动物的营养和免疫方面也具有开发价值。文章主要从3个方面综述了国内外关于柑橘渣作为饲料资源开发的研究进展:①柑橘渣的不同加工处理方法对营养成分的影响;②柑橘渣在牛、羊、猪、家禽生产方面,特别是在反刍动物饲料中的应用;③柑桔渣作为添加剂在饲料加工业中的研究和应用。  相似文献   

14.
Extract

When an immune serum is fractionated into its major components, for example by electrophoresis, the bulk of its antibody activity is seen to occur in the gamma globulins with some slight additional activity in the beta globulins. Proteins that have antibody activity are called immunoglobulins; these are divided into classes which differ in their structure and biology. Five such classes, designated IgG, IgM, IgA, IgD, and IgE, have been described in man. Immunoglobulins analogous to those of man probably occur in all mammals but in most species they remain to be specifically identified. Furthermore, the features of a given immunoglobulin class are broadly the same regardless of the species in which it occurs.  相似文献   

15.
The history of teratology is reviewed. Methods available for causing malformations in mammals by subtle changes in the environment during pregnancy are discussed. A table is provided in which the commoner teratogens are listed. Methods are described by means of which the activity of some common teratogens may be opposed. The occurrence at Battle Creek, Michigan, USA, of a chemical agent dangerous to health, life and development of all mammals is described. This gives an indication that injury and death to all mammals, as in the Sevaso disaster, including teratogenesis may be expected to be a fairly frequent occurrence in the years to come.  相似文献   

16.
A survey is given of different methods used for the estimation of the net energy lactation and the digestible crude protein content of forages (grass hay, grass silage, maize silage) as well as tuber crops (fodder beet, turnips, raw potatoes), by-products (dried sugarbeet pulp, pressed sugarbeet pulp), compound feeds and raw ingredients for dairy cattle. The following methods are discussed: --methods only based on chemical parameters: crude fibre and cell walls. --methods using rumen fluid from fistulated animals: the two step in vitro digestibility technique, the Hohenheim Futterwert test. --methods using enzyme (cellulase) preparations. --the near infrared reflection spectroscopy. The estimation of the energy value of raw ingredients is discussed more in detail. Formulas for the rapid calculation of the energy value of pulp and tubers are reported. The results obtained at the National Institute for Animal Nutrition in Melle-Gontrode with the two step in vitro digestion technique and a developed cellulase method are illustrated more in detail.  相似文献   

17.
Small exotic mammals have been companions to people for almost as long as dogs and cats have been. The challenge for veterinary medicine today is to decipher the tea leaves and determine whether small mammals are fad or transient pets or whether they will still be popular in 20 years. This article focuses on pet small-mammal medicine, as the concerns of the laboratory animal are better known and may differ profoundly from those of a pet. Dozens of species of small exotic mammals are kept as pets. These pet small-mammal species have historically served human purposes other than companionship: for hunting, for their pelts, or for meat. Now, they are common pets. At present, most veterinary schools lack courses in the medical care of these animals. Veterinary students need at least one required class to introduce them to these pets. Currently, there are no small-mammal-only residency programs. This does not correspond with current needs. The only way to judge current needs is by assessing what employers are looking for. In a recent JAVMA classified section, almost 30% of small-animal practices in suburban/urban areas were hiring veterinarians with knowledge of exotic pets. All veterinarians must recognize that pet exotic small mammals have changed the landscape of small-animal medicine. It is a reality that, today, many small-animal practices see pet exotic small mammals on a daily basis.  相似文献   

18.
Nucleotides and carob pulp were tested as possible alternatives to antimicrobial growth promoters for newly weaned pigs. Four dietary treatments were used: basal diet, nucleotides, carob pulp and nucleotides + carob pulp. Performance was measured in a group of 72 pigs. Another group of 60 pigs was used for histological measurements of the jejunal mucosa and microbiological measurements by RFLP in ileum and caecum at different post-weaning intervals. Treatment did not affect performance. On the other hand, the morphology parameters of the jejunum were significantly (P < 0.001) affected by day after-weaning. No effects (P > 0.05) of treatment were observed on these parameters. The similarity (intra and inter-group) of the intestinal microbiota decreased with day after-weaning (P < 0.001) and was also affected by dietary treatment (P < 0.05). The nucleotide diets had the highest similarities in the ileum whereas the carob pulp diets had the lowest in the caecum. It is concluded that both nucleotides and carob pulp are able to modulate the changes in microbiota composition after weaning and that whereas nucleotides act in the ileum, carob pulp acts in the caecum.  相似文献   

19.
Reasons for performing study: Cheek teeth (CT) diastemata are a major equine dental disorder that can be treated by mechanically widening the diastemata. There is limited anatomical knowledge of the spatial relationships of the individual pulps to the adjacent interproximal surfaces; on the risks of exposing the 6th pulp horn when performing the clinically unproven ‘bit seating’ procedure on Triadan 06s. Objectives: To describe the anatomical relationships between the occlusal and interproximal surfaces of CT and the adjacent pulp horns; and between the 6th pulp horn and the occlusal and rostral surfaces of Triadan 06s. Methods: The CT from 30 skulls of horses subjected to euthanasia for non‐dental reasons were sectioned to expose the rostrally and caudally situated pulp horns to allow the anatomical relationships between the pulp horns and the occlusal and interproximal aspects of the CT to be assessed. Results: Pulp horns were mean ± s.d. of 5.74 ± 1.45 (range 1.3–10.8 mm) from the nearest interproximal surface, with 5.3% of pulp horns being <3.5 mm from the interproximal surface. In contrast to expectations, pulps tended to became closer to the interproximal surface (and also to the occlusal surface) with increasing age. Teeth with physiologically tall clinical crowns, and also those in the Triadan 09 position had pulps that were closer to the interproximal surfaces than the remaining CT. The more caudally situated pulp horns, i.e. in particular, the 4th maxillary and 5th mandibular pulp horns were closer to the interproximal surfaces than the remaining pulp horns and these pulp horns also had the thinnest sub‐occlusal secondary dentine. Pulps that were close to the interproximal surface were also found to be close to the occlusal surface of the CT. Conclusions and potential relevance: While diastema widening is theoretically safe between the majority of CT, a small proportion of pulp horns are only 1.3 mm from an interproximal surface and others lie just 1.6 mm beneath the occlusal surface, and such pulps are at risk of pulpar exposure and to thermal injury during this procedure. The risk of pulpar exposure increases when dental tissue is removed from the caudal aspects of CT.  相似文献   

20.
The Chlamydiales are a unique order of intracellular bacterial pathogens that cause significant disease of birds and animals, including humans. The recent development of a Chlamydiales-specific 16S rDNA polymerase chain reaction (PCR) assay has enabled the identification of Chlamydiales DNA from an increasing range of hosts and environmental sources. Whereas the Australian marsupial, the koala, has previously been shown to harbour several Chlamydiales types, no other Australian marsupials have been analysed. We therefore used a 16S rDNA PCR assay combined with direct sequencing to determine the presence and genotype of Chlamydiales in five wild Australian mammals (gliders, possums, bilbies, bandicoots, potoroos). We detected eight previously observed Chlamydiales genotypes as well as 10 new Chlamydiales sequences from these five Australian mammals. In addition to PCR analysis we used antigen specific staining and in vitro culture in HEp-2 cell monolayers to confirm some of the identifications. A strong association between ocular PCR positivity and the presence of clinical disease (conjunctivitis, proliferation of the eyelid) was observed in two of the species studied, gliders and bandicoots, whereas little clinical disease was observed in the other animals studied. These findings provide further evidence that novel Chlamydiales infections occur in a wide range of hosts and that, in some of these, the chlamydial infections may contribute to clinical disease.  相似文献   

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