Caracal Research Articles

Sensitivity of a methematical model used to optimize revenue in a predation-competative farming environment

Sheep farmers in the Cape Midlands region of South Africa frequently sustain stock losses through predation by caracal lynx. Further losses are incurred when hyrax compete with sheep for available pasture. Hyrax constitute the natural prey for lynx with the result that culling either hyrax or lynx has complicated feedback effects. In order to investigate the spill-over problems from the natural predator-prey system on farming revenue, a differential equations model was previously formulated, comprising the sectors Hyrax, Lynx, Sheep, Pasture and Revenue and an optimisation procedure was used to determine the optimal culling rate policy for farmers. The purpose of this paper is to investigate the numerical, behavioural and policy sensitivity of this model to parameter uncertainty.

A mathematical model to analyze predation and competition problems in a sheep‐farming region

AbstractSheep farmers in the Cape Midlands region of South Africa frequently sustain stock losses through predation by caracal lynx. Further losses are incurred because of hyrax competing with the sheep for pasture. As hyrax constitute the principal food of lynx, culling either hyrax or lynx has complex feedback effects.A system dynamics model of this system comprising sheep, hyrax, lynx, pasture, and revenue sectors has been formulated. The model is used to simulate the system under different culling strategies.By comparing stock positions and farming revenue generated over a number of years under different culling strategies, an optimal culling policy is determined using an optimization procedure. A parameter sensitivity analysis reveals that the policy recommendations are relatively insensitive to parameter uncertainty.

Cystine calculi in a caracal lynx ( Felis caracal)

One hundred and sixty cystine micro calculi caused total urethral obstruction in an adult male caracal lynx. Death occurred due to ruptureof the urinary bladder. The rare occurrence of cystine calculi in Felidae is discussed, together with the occurrence of cystinuria in man.

Vitamin A in the Liver and Kidney of Some Felidae

Liver and kidney vitamin A reserves of forty-one Felidae in a Zoological garden have been recorded. Liver vitamin A reserves were low in enteric disease. Storage of large quantities of vitamin A in the kidney is not characteristic of all Felidae and only in the kidneys of jungle cat and caracal lynx were appreciable quantities found. The presence of fat in the renal tubules was confirmed. There was no excretion of vitamin A in urines examined nor any evidence of large quantities of fat being excreted, save in the tiger. It is suggested that when a meat diet is fed, with the calcium/phosphorus ratio corrected to 1: 1, 200 i.u. of vitamin A per kg. provides for adequate liver storage. Vitamin A deficiency in lion cubs is discussed. Les reserves en vitamine A hépatique et renale chez 41 Félidés d’un jardin zoologique ont été enregistrées. Les reserves hépatiques étaient basses en cas de maladies entériques. Le magasinage de grandes quantités de vitamine A n'est pas characteristique de tous le Félidés et des quantités appreciables dans les reins ont été observées seulement chez le chat de la jungle et le caracal. La presence de gras dans le tubules renales a été confirmée. Aucune evidence d’excrétion de vitamine A n’a été observée dans les échantillons examinés; également, aucune evidence n’a été observée d’excretion de grandes quantités de gras, sauf chez le tigre. On suggére que lorsque l’alimentation consiste en viande et le rapport calcium/phosphorus est ajusté à 1:1, 200 unités internationales suffisent pour un magasinage hépatique adéquat. La carence de vitamine A chez les lionceaux est discutée. Der Vitamin A Gehalt der Leber und Nieren wurde in 41 Tieren der Felidae Familie eines zoologischen Gartens bestimmt. Darmstörungen waren von einem Vitamin A Mangel begleitet. In der Regel gab es keine Speicherung des Vitamins in den Nieren von Felidae, und beträchtliche Mengen wurden nur in den Nieren von Dschungelkatzen und Caracal-Lüchsen gefunden. Gegenwart von Fett in den Nierenkanälchen wurde bestätigt. Im Harn wurde kein Vitamin A entdeckt, mit Ausnahme des Tigers enthielt der Harn auch kein Fett. Es wurde vorgeschlagen, dass in einer Fleischkost mit einem korrigierten Kalzium-Phosphorverhältnis von 1:1, ein Vitamin A Gehalt von 200 I.E. pro kg. für genügende Leberspeicherung sorgt. Das Problem von Vitamin A Mangel in jungen Löwen wurde diskutiert. Las reservas de vitamina A en el hígado y riñón de 41 félidos en un jardín zoológico han sido enregistradas. Las reservas hepáticas han sido bajas durante enfermedades entéricas. El depósito de grandes cantidades de vitamina A en el riñón no es caracteristico de todos los félidos y solo en los riñónes del gato de la jungla y de la lince de la estepa han sido observadas cantidades apreciables. Se comproba la presencia de graso en los túbulos renales. En las muestras de orina examinadas no ha sido observada excreción de vitamina A ni evidencia de importantes excreciones de graso, excepto en la tigra. Se sugiere que cuando el régimen alimenticio consiste en carne y la razón de calcio/fosforo es ajustada a 1:1, 200 unidades internacionales de vitamina A por kg. de peso corporal provée un depósito hepático adecuado. Se discute la carencia de vitamina A en los cachorros de león.

A note on the birth of Caracal lynx Felis caracal at Mysore Zoo

A note on the birth of Caracal lynx <i>Felis caracal</i> at Mysore Zoo

Haemaphysalis kutchensis sp. n., a Common Larval and Nymphal Parasite of Birds in Northwestern India (Ixodoidea, Ixodidae)

Both sexes and each stage of Haemaphysalis kutchensis sp. n. are described. This species is common, as larvae and nymphs, on a variety of birds in the comparatively dry Kutch area of Gujerat State in northwestern India. It also occurs in Maharashtra and Rajasthan states. Adults have been found on mammals, hares and a variety of carnivores, and on large ground birds. Kutch is on a busy flyway between Central Asia and southern India and Ceylon, and larvae and nymphs are active during both spring and fall migration periods of birds. H. kutchensis sp. n. appears to be related to H. howletti Warburton and to H. campanulata Warburton, but is easily differentiated from these species. Immature stages of Haemaphysalis kutchensis sp. n., described below, are common on a variety of birds in the comparatively dry Kutch and other areas of Gujerat State, India. Several records of adults are from Maharashtra and Rajasthan states in western India. Adults have been found on hares and a variety of carnivores and on large ground birds. Kutch is on a busy flyway of birds migrating between Central Asia and southern India and Ceylon. Larvae and nymphs were taken on birds in Kutch during both the spring and fall migration periods of 1960 by staff members of the Virus Research Centre, Poona. Haemaphysalis kutchensis sp. n. The Kutch Haemaphysalid (Figs. 1 to 28) Haemaphysalis bispinosa var. intermedia Warburton and Nuttall, 1909; Nuttall and Warburton, 1915, p. 433-435, Fig. 363 of $ represents H. Received for publication 25 February 1963. * From Research Project MR005.09-1402.3, Bureau of Medicine and Surgery, Navy Department, Washington 25, D. C. The opinions and assertions contained herein are the private ones of the authors and are not to be construed as official or reflecting the views of the Navy Department or the naval service at large. t Department of Medical Zoology, United States Naval Medical Research Unit Number Three, Cairo, Egypt, U.A.R. $ Staff Member, the Rockefeller Foundation, Virus Research Centre, Poona, India. The Virus Research Centre is jointly maintained by the Indian Council of Medical Research and the Rockefeller Foundation. kutchensis sp. n.; Fig. 364 of 9 represents H. intermedia W. and N., 1909 (see Trapido and Hoogstraal, 1963). Holotype: Male, VRC laboratory reared (No. 91) from nymph collected from bird at Kuar Bet, Kutch, Gujerat State, India, March 1960, by Virus Research Centre personnel. Deposited in collection of Rocky Mountain Laboratory, Hamilton, Montana (RML 38426). Allotype: Female; data and depository as for holotype. Par types: Total 70 $ $, 43 9 9,53 nymphs or nymphal pelts (reared to adults), 36 larvae. From Nuttall collection, identified as H. bispinosa intermedia, in British Museum (Natural History) and redeposited in BM(NH). 1 $, 1 9, from Indian Hare, Lepus nigricollis ruficaudatus Geoffrey, Shamghar, Raiasthan, India, March 1911, N. B. Kinnear legit (N1686). 2 9 9, cat, Agra, Uttar Pradesh, India, 1907, E. H. Hankin legit (N327). 1 $, Striped Hyena, Hyaena h. hyaena (Linnaeus, 1758), Ghodasgaon, Kandeish (now Maharashtra State), 4 May 1911, C. A. Crump legit (N1665). 2 $ $, 1 9, Indian Wolf, Canis lupus pallipes Sykes, 1831, Charwa, Cutch (now Kutch District, Guierat State), 1911, C. A. Crump legit (N1680). 1 $, Caracal Lynx, Felis caracal schmitzi Matschie, 1912, Bhuj, Cutch (now Kutch District, Gujerat State), 19 August 1911, C. A. Crump legit (N1682). 2 $ $, Jungle Cat, Felis chaus subsp. (= Felis affinis), Ghodasgaon, Kandeish (now Maharashtra State), 5 May 1911, C. A. Crump legit (N1666). 4 $ $, Jungle Cat, Felis chaus subsp., Nohaman, 1911 (Kinnear 264a). Note: Scientific names of host animals in this paragraph are the present-day usage for old names on labels. All the following paratypes were collected in Gujerat State in 1980 (one specimen in 1961) by Virus Research Centre personnel. All paratypes in the first paragraph below were collected as nymphs on hosts indicated and reared to adults. (F1 larvae and nymphs also obtained from VRC