Fabrício Singaretti de Oliveira

Gross anatomical study of the aortic ARC branches of the paca (Agouti paca, Linnaeus, 1766)

It was described the distribution of the aortic arc in eight animals of the Agouti paca species, which were 2 adult females, 3 young males and 3 young females that came from the Wild Animal Sector at the Faculty of Agrarian and Veterinary Sciences of Jaboticabal - UNESP. After natural death, the animals had their arterial vessels injected with Neoprene latex 650® coloured by a specific pigment and set in a 10% formalin solution. After dissection, it was noticed that the aortic arc gives off the left subclavian artery and the brachiocephalic trunk. The latter originates the left carotid common artery and other trunk, that gives off the right carotid common artery and the right subclavian artery, that originates the vertebral artery, the costocervical trunk, the superficial cervical artery, the axillary artery and the internal thoracic artery, as well as it happens in the left subclavian artery. In just one animal, the left common carotid artery takes a siphon-shaped path just after its origin in the right subclavian artery. In other animals, the left common carotid artery occurs as a straight path.

Anatomoradiographic description of the teeth of pacas bred in captivity (Agouti paca, Linnaeus, 1766)

Two newborn males, two adult males 9 and 72 months old, one newborn female and two adult females of 30 and 54 months old pacas were used. Animals were radiographed on lateral recumbency, teeth were extracted and the vestibulolingual and mesiodistal lengths were achieved at the occlusal surface, besides the longitudinal length. The lower incisors presented greater length in relation to the other ones and sinuous shape; the upper incisors, relatively smaller, are practically straight. There is no canine tooth, and after a great diastema there is one premolar and three molars in each hemiarcade. In adult pacas, the enamel of incisors presents yellowish colour, mainly in the labial surface; in the premolars and molars, the enamel is present as internal sheets disposed nearly in a parallel way and in vestibulolingual direction, through practically all the dental length, which provides several joined teeth aspect.

Real time B-mode ultrasound in pacas pregnancy (Agouti paca, Linnaeus, 1766)

The aim of this study was to establish the pregnancy period of paca by means of ultrasound use. Nine pregnant pacas were periodically scanned with a two-frequency sectorial electronic transducer of 5.0 and 7.5 MHz, in B mode, from ultrasound detection of embryo vesicle or fetus until the parturition. Animals were placed in an iron-bar squeeze cage and remained in standing position during sessions. A dark cloth was used to cover the cage and fruits were offered during ultrasound session to avoid aggressive reactions. The more premature occurred detection of pregnancy, the greater the period of ultrasound examination until the birth of the offspring. All gestation delivered only one newborn weighting 796.5 ± 74.36 grams (mean value ± standard error of the sample) and 33.46 ± 0.60 centimeters (mean value ± standard error of the sample) of length (from rostral edge of nose and distal portion of tail). The length of paca pregnancy ranged from 135 to 139 days.

Hemi-ovariossalpingohisterectomia em pacas prenhes e posterior ocorrência de prenhez (Agouti paca, Linnaeus, 1766)

The hemiovarysalpingohysterectomy in five captive pregnant pacas kept on the Wild Animal Section at the College of Agricultural and Veterinarian Sciences (FCAV-UNESP) in Jaboticabal, Sao Paulo, Brazil, was conducted aiming at verifying the further occurrence of pregnancy on the remaining uterine horn. The tranquilization was achieved by using azaperone (4mg/kg) and consequent application of atropine sulphate (0.06mg/kg) and the association of ketamine (20mg/kg) and xylazine (1.5mg/kg) cloridrates, on the same syringe, for induction of anesthesia. The general anesthesia was performed via a face mask with halothane. By means of median laparotomy, the uterine horn with the fetus, the ovary and the uterine tube, all from the same antimere, were taken out. Antibiotics (30,000IU/kg of three penicillins and 12.5mg/kg of two streptomycins) and analgesic (buprenorfine 0.02 mg/kg) were injected immediately after surgery and repeated after two days. All injections were made intramuscularly. In spite of the permanence of only one ovary after surgery, new pregnancy occurred in the remaining uterine horn in the five females which went through surgery, and the birth (solely one by delivery) happened 210, 248, 276, 302 and 310 days after the hemiovarysalpingohysterectomy.

Erupção dental em pacas (Agouti paca) criadas em cativeiro

ABSTRACT Five females and seven males of Agouti paca were used to study dental eruption. In a monthly radiographic survey of the dental eruption, during 30 consecutive months, animals were radiographed. Pacas were born with three teeth in each dental hemiarcade, one incisor of continuous growth, one premolar (the only one deciduous) and one molar. The second molar erupted in the fourth month. The occlusal surfaces of lower teeth were at the same level in the sixth month and the upper teeth around ninth month. The beginning of the third molar eruption occurred in the 14th month. Perception of the first permanent premolar was around the 16th month, and its correspondent deciduous was still retained. The occlusal surfaces of upper and lower teeth were at the same level in the 21st month. The eruption of the first lower deciduous premolar occurred between the 22nd and 24th month and the upper´s between the 23rd and 24th month. The occlusal surfaces of lower teeth were at the same level between the 24th and 25th month and the upper’s on the 27th month. Keywords: dental eruption, agouti paca, captivity

Intramyocardial course of the coronary arteries in the marsh deer (Blastocerus dichotomus)

O trajeto das arterias coronarias foi estudado no cervo-do-pantanal para comparacao com os ruminantes domesticos. A arteria coronaria esquerda se origina na aorta, na superficie auricular cardiaca e divide-se em ramos paraconal e circunflexo, os quais preenchem o sulco paraconal interventricular e sulco subsinuoso, respectivamente; esta arteria tambem origina um ramo para o conus arteriosus imediatamente antes de entrar no miocardio. A arteria coronaria direita surge da aorta, na borda cranial cardiaca e termina nesta borda, proximo ao sulco subsinuoso interventricular, entretanto, sem preenche-lo.

Uniparidade em pacas criadas em cativeiro (Agouti paca, Linnaeus, 1766)

Durante quatro anos foram detectadas 25 prenhezes, em 13 diferentes pacas, por meio de ultra-sonografia. Apos a deteccao ultra-sonografica, as femeas foram separadas em baias individuais para o nascimento dos filhotes e ai mantidas ate o desmame. Houve nascimento de apenas um animal por parto, ressaltando a caracteristica reprodutiva de uniparidade, o que sugere a tendencia de nascimento de apenas um filhote por parto, nessa especie.

Microscopic Characterization of Teeth of Pacas Bred in Captivity (Agouti paca, Linnaeus, 1766)

The microscopic description of the teeth of pacas (Agouti paca) bred in captivity was developed for providing biological data on one of the largest American wild rodents, as not many references exist in the literature about this species. Two newborn males, two adult males (9 and 72 months old), one newborn female and two adult females (30 and 54 months old) were used after death due to fights, neonatal cannibalism or unknown causes. Animals were radiographed, and their teeth were extracted and put on an acrylic resin block, cut on a diamond‐like disc microtome and diaphanized. It was noted that enamel surrounds the coronary dentine and projects to the root region, besides being present as internal laminae, arranged in a parallel way and in the vestibulolingual direction. The dentine is located between the enamel laminae and surrounds the pulp horns. The cementum is located internal to the enamel laminae. From scanning electronic microscopy, we find that the enamel is the outer element on the vestibular surface, and it is in direct contact with the dentine. On the lingual surface, the cementum and dentine are the outer elements.

Handling of female pacas (Agouti paca, Linnaeus, 1766) for ultrasound pregnancy detection

A paca e um roedor sul-americano cujo manejo, tranquilizacao ou anestesia oferece um grande campo de pesquisa devido aos poucos artigos existentes. Doze pacas femeas adultas foram utilizadas, mantidas separadas em seis baias, sendo capturadas com um puca de polipropileno e levadas a uma sala na qual se realizava a tricotomia abdominal. Apos, os animais eram colocados em uma gaiola de ferro de compressao lateral. A sessao de ultra-sonografia era realizada em modo B com um transdutor setorial eletronico de 5,0 e 7,5 MHz. Para a diminuicao do estresse causado pelos procedimentos, a tranquilizacao das femeas era realizada com diazepam e maleato de midazolam por via oral. Ambos demonstraram-se efetivos na tranquilizacao das pacas previamente e durante as sessoes, sendo que o maleato de midazolam proporcionou um melhor manejo dos animais.

Assessing the effectiveness of 30% sodium chloride aqueous solution for the preservation of fixed anatomical specimens: a 5‐year follow‐up study

Anatomical specimens used in human or veterinary anatomy laboratories are usually prepared with formaldehyde (a cancerous and teratogenic substance), glycerin (an expensive and viscous fluid), or ethanol (which is flammable). This research aimed to verify the viability of an aqueous 30% sodium chloride solution for preservation of anatomical specimens previously fixed with formaldehyde. Anatomical specimens of ruminant, carnivorous, equine, swine and birds were used. All were previously fixed with an aqueous 20% formaldehyde solution and held for 7 days in a 10% aqueous solution of the same active ingredient. During the first phase of the experiment, small specimens of animal tissue previously fixed in formaldehyde were distributed in vials with different concentrations of formaldehyde, with or without 30% sodium chloride solution, a group containing only 30% sodium chloride, and a control group containing only water. During this phase, no contamination was observed in any specimen containing 30% sodium chloride solution, whether alone or in combination with different concentrations of formaldehyde. In the second phase of the experiment, the 30% sodium chloride solution, found to be optimal in the first phase of the experiment, was tested for its long-term preservation properties. For a period of 5 years, the preserved specimens were evaluated three times a week for visual contamination, odors, and changes in color and texture. There was no visual contamination or decay found in any specimen. Furthermore, no strange odors, or changes in color or softness were noted. The 30% sodium chloride solution was determined to be effective in the preservation of anatomic specimens previously fixed in formaldehyde.Anatomical specimens used in human or veterinary anatomy laboratories are usually prepared with formaldehyde (a cancerous and teratogenic substance), glycerin (an expensive and viscous fluid), or ethanol (which is flammable). This research aimed to verify the viability of an aqueous 30% sodium chloride solution for preservation of anatomical specimens previously fixed with formaldehyde. Anatomical specimens of ruminant, carnivorous, equine, swine and birds were used. All were previously fixed with an aqueous 20% formaldehyde solution and held for 7 days in a 10% aqueous solution of the same active ingredient. During the first phase of the experiment, small specimens of animal tissue previously fixed in formaldehyde were distributed in vials with different concentrations of formaldehyde, with or without 30% sodium chloride solution, a group containing only 30% sodium chloride, and a control group containing only water. During this phase, no contamination was observed in any specimen containing 30% sodium chloride solution, whether alone or in combination with different concentrations of formaldehyde. In the second phase of the experiment, the 30% sodium chloride solution, found to be optimal in the first phase of the experiment, was tested for its long‐term preservation properties. For a period of 5 years, the preserved specimens were evaluated three times a week for visual contamination, odors, and changes in color and texture. There was no visual contamination or decay found in any specimen. Furthermore, no strange odors, or changes in color or softness were noted. The 30% sodium chloride solution was determined to be effective in the preservation of anatomic specimens previously fixed in formaldehyde.