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Simple Summary Infrared thermography is a clinically useful method for detecting physiopathological alterations in animals through microvascular changes. It has been adapted for applications with large species, as a support tool in evaluating animal welfare, and can also contribute to productive and reproductive evaluations. This review discusses the thermal windows currently in use and characterizes their differences and limitations as resources for early detection and diagnosis in cattle and river buffaloes. Abstract Infrared thermography (IRT) is a non-ionizing, non-invasive technique that permits evaluating the comfort levels of animals, a topic of concern due to the growing interest in determining the state of health and welfare of production animals. The operating principle of IRT is detecting the heat irradiated in anatomical regions characterized by a high density of near-surface blood vessels that can regulate temperature gain or loss from/to the environment by modifying blood flow. This is essential for understanding the various vascular thermoregulation mechanisms of different species, such as rodents and ruminants’ tails. The usefulness of ocular, nasal, and vulvar thermal windows in the orbital (regio orbitalis), nasal (regio nasalis), and urogenital (regio urogenitalis) regions, respectively, has been demonstrated in cattle. However, recent evidence for the river buffalo has detected discrepancies in the data gathered from distinct thermal regions in these large ruminants, suggesting a limited sensitivity and specificity when used with this species due to various factors: the presence of hair, ambient temperature, and anatomical features, such as skin thickness and variations in blood supplies to different regions. In this review, a literature search was conducted in Scopus, Web of Science, ScienceDirect, and PubMed, using keyword combinations that included “infrared thermography”, “water buffalo”, “river buffalo” “thermoregulation”, “microvascular changes”, “lacrimal caruncle”, “udder”, “mastitis”, and “nostril”. We discuss recent findings on four thermal windows—the orbital and nasal regions, mammary gland in the udder region (regio uberis), and vulvar in the urogenital region (regio urogenitalis)—to elucidate the factors that modulate and intervene in validating thermal windows and interpreting the information they provide, as it relates to the clinical usefulness of IRT for cattle (Bos) and the river buffalo (Bubalus bubalis).

La crianza de camélidos sudamericanos domésticos, alpaca y llama, es la principal fuente de subsistencia en la zona altoandina peruana. El objetivo del estudio fue evaluar las características de manejo y transporte hacia el camal de los camélidos sudamericanos, considerando los criterios basados en el bienestar animal, usando las lesiones contusas halladas en la carcasa como indicador. Se recolectó información del camal municipal de la ciudad de Huancavelica, Perú. Se seleccionaron 203 canales y se revisaron después de la faena para observar la presencia de lesiones. Se registró información sobre la cantidad de animales transportados, detalles del transporte y características del manejo de los animales. De las 203 canales evaluadas se contabilizó un total de 1,418 lesiones con un promedio de 6.9 ± 0.2 por carcasa, además se registraron cuatro animales con contusión generalizada (1.9 %). Se contabilizaron 27 medios de transporte, siendo la mitad de ellos autos (50.0 %). La presentación de lesiones grados 2 y 3 están asociadas al traslado en cualquier tipo de vehículo (OR= 2.20; IC95%: 1.27 – 3.82) y a la no restricción de visión (OR= 2.26; IC95%: 1.66 – 3.06). También las lesiones extensas están asociadas al tiempo de espera pre-sacrificio mayor a las 24 h (OR= 1.42; IC95%: 0.99 – 2.03). Se evidencia que las malas características de los vehículos, malas condiciones de transporte y manejo, aumentan la probabilidad de encontrar lesiones en las canales. Por lo tanto, no se cumplen con los criterios de bienestar animal durante el manejo y transporte de los camélidos sudamericanos., Raising South American domestic camelids is the main source of subsistence in the Peruvian Andes. Under the understanding that pre-slaughter handling and transport practices can affect meat quality an evaluation was done of South American camelids based on animal welfare criteria and carcass lesions. Data were collected at the Huancavelica municipal slaughterhouse, Peru. A total of 203 carcasses were inspected post-slaughter for lesions from trauma. Information collected on transport included number of animals transported per vehicle, transport characteristics and animal handling practices. Every one of the 203 evaluated carcasses exhibited evidence of pre-slaughter mistreatment. A total of 1,418 lesions were recorded, with an average of 6.9 ± 0.2 per carcass; four animals (1.9 %) exhibited generalized traumas. Of the 27 animal group arrivals, half were in cars (50.0 %). Grade 2 and 3 lesions were associated with transport in any vehicle type (OR= 2.20, 95% CI: 1.27 - 3.82), and no vision restriction (OR= 2.26, 95% CI: 1.66 - 3.06). Large area lesions were associated with pre-slaughter wait times greater than 24 h (OR= 1.42, 95% CI: 0.99 - 2.03). South American camelid transport and handling practices at the studied slaughterhouse were generally poor and clearly compromised carcass quality as evidenced by ubiquitous lesions. Animal welfare criteria and regulations for South American camelids were not fulfilled., Facultad de Ciencias Veterinarias

Este estudio describe las arterias que irrigan el páncreas e intestino delgado de la alpaca mediante disección, angiografía, repleción vascular e histología. Se emplearon seis alpacas, de las cuales cuatro fueron mayores de dos años y dos de cuatro meses. Macroscópicamente, el páncreas estuvo irrigado principalmente por las arterias pancreática duodenal craneal y caudal; además, ramas provenientes de la arteria hepática, arteria esplénica y la rama de la primera arteria yeyunal. Estas arterias y ramas ingresaron al páncreas (porción izquierda, derecha y cuerpo) formando anastomosis en forma de redes, en el interior del parénquima. Las técnicas histológicas evidenciaron que las capas de las arterias de la alpaca presentan dos capas, compacta y esponjosa, conformando la túnica adventicia de las arterias pancreática duodenal craneal y caudal, celíaca y mesentérica craneal. La arteria pancreática duodenal caudal tuvo la capa adventicia compacta más gruesa, siendo esta arteria la que irriga el lóbulo derecho pancreático, parte del lóbulo izquierdo y el duodeno.

There is a high demand for a veterinary education in animal welfare (AW) with different approaches from the academic, society and trade points of view. Latin American (LA) countries members of the World Organization for Animal Health (OIE) are under the urge and should be obligated to teach AW. The aims of this article are to analyze the current drives of change on the importance of teaching animal welfare in LA, the competences recommended from international education organizations for the region, and to provide the contents on the curriculum in AW that a future veterinarian should achieve in the LA scenario, in other words to examine why teaching AW, what should be taught and how. Despite significant advances in introducing AW into veterinary training programs, much remains to be done regarding the future of this field in teaching veterinary science in Spain and LA countries, and in including this science as an independent course in programs at distinct levels to integrate the scientific, ethical and legal aspects of AW. This paper presents a proposal that was constructed with a view towards integrating diverse curricular approaches based on criteria, contents and concepts provided by the researchers and professors who collaborated in the book entitled: Bienestar Animal: Una Visión Global en Iberoamerica [Animal Welfare: A Global Vision in Ibero-America]. To ensure veterinary students will be better equipped to graduate with OIE day 1 competencies in AW, teaching approaches are needed that support project-based learning and gamification, critical thinking, reflection and collaborative learning. Keywords: Animal welfare, Study plans, Study programs, Teaching, Veterinary medicine

Simple Summary We pose based on a fundamental science examination that events that occur around the time of slaughter have the potential to intensify the pain response, through a process called sensitisation, or an exaggerated response to painful stimuli. Health conditions which result in inflammation, injuries arising from transport and handling and exaggerated fear responses may all be present at the slaughterhouse. Whilst there is limited evidence of a direct effect of these on the processes of sensitisation in animals at slaughter, by analogy with the human neurobiology literature the connection seems plausible. In this review we outline the biology of such a response, and the rationale for suggestion of a possible linkage between events at slaughter and a heightened animal pain response. Abstract We pose, based on a neurobiological examination, that events that occur around the time of slaughter have the potential to intensify the pain response, through the processes of sensitisation and enhanced transmission. Sensitisation, or an enhanced response to painful stimuli, is a well-discussed phenomenon in the human medical literature, which can arise from previous injury to an area, inflammatory reactions, or previous overstimulation of the stress axes. A number of events that occur prior to arrival at, or in the slaughterhouse, may lead to presence of these factors. This includes previous on-farm pathology, injuries arising from transport and handling and lack of habituation to humans. Whilst there is limited evidence of a direct effect of these on the processes of sensitisation in animals at slaughter, by analogy with the human neurobiology literature the connection seems plausible. In this review a neurobiological approach is taken to discuss this hypothesis in the light of basic science, and extrapolations from existing literature on the slaughter of ruminants. To confirm the postulated link between events at slaughter, and processes of hypersensitisation, further dedicated study is required.

The liver has multiple functions that change throughout ontogeny. South American camelids (SAC) have unique characteristics related to adaptation to extreme environments and metabolism. However, the process of hepatic cell differentiation has not been studied in any SAC. We study the patterns of cell differentiation and proliferation in the liver of the alpaca at different times of the ontogeny, excluding the hematopoietic components. Immunohistochemical techniques were performed in 66 specimens, including embryos, fetuses, neonates and adults. Supplementary analyses were performed by lectinhistochemistry. The hepatocytic differentiation was performed by the identification of Hepatocyte (Clone: ​​OCH1ES Dako®). It began in the specimens of 1.8−2.5 cm of crown to rump length (CRL), from Days 25–29 (ovulation = Day 0), continued during gestation and intensified towards its end. The cholangiocytic differentiation was performed by the identification of cytokeratin 7 (CK7, Dako®). It was manifested at the final of gestation (specimens of 28.4 cm CRL, from Day 223 onwards). Parenchymal cells underwent a process of gradual differentiation (differentiation of hepatocytes preceded that of cholangiocytes). Cell proliferation was observed along gestation using the nuclear proliferation antigen (PCNA) and Ki-67. Hepatic organogenesis in the alpacas shares similar differentiation and proliferation mechanisms with other altricial, but phylogenetically distant, species.

Heat stress is one of the environmental factors that most severely affects milk industry, as it has impact on production, immune responses and reproductive performance. The present study was conducted with high-performance Holando-Argentino cows. Our objective was to study TNF-α and its receptors pattern expression in cows from a region characterized by extreme climatic seasonality. Animals were evaluated in three periods: spring (n = 15), summer (n = 14) and autumn (n = 11). Meteorological records from a local station were used to estimate the temperature and humidity index (THI) by means of an equation previously defined. A THI higher than 68 is indicative of stressing conditions. During the summer period, the animals were exposed to 8.5 ± 1.09 h of heat stress, or THI > 68. In spring, stress hours were reduced to 1.4 ± 0.5 every day, while during the autumn, there were no recorded heat stress events. Expression of TNF-α, and its receptors was determined by qPCR. During the summer, TNF-α and its receptors expression diminished drastically compared to the rest of the year, when stressful conditions were infrequent. We conclude that animals that are not physiologically prepared to resist high temperatures might have a less efficient immune response, reinforcing the need to develop new strategies to improve animal welfare.

Simple Summary The current immune, metabolic, and neural pathways and the structures involved in developing the febrile response and, in return, to thermal homeostasis are known. There is still much information to be revealed about the underlying mechanisms that participate in the febrile process and the control of energy balance. This review analyzes the recent advances in pathophysiological mechanisms of the febrile process, the heat loss in an animal with fever, thermoregulation, the adverse effects of fever, and recent scientific findings related to different pathologies in farm animals through the use of infrared thermography, a fast, reliable, and non-invasive tool that is useful in the early detection of pathologies of clinical importance. Abstract Body-temperature elevations are multifactorial in origin and classified as hyperthermia as a rise in temperature due to alterations in the thermoregulation mechanism; the body loses the ability to control or regulate body temperature. In contrast, fever is a controlled state, since the body adjusts its stable temperature range to increase body temperature without losing the thermoregulation capacity. Fever refers to an acute phase response that confers a survival benefit on the body, raising core body temperature during infection or systemic inflammation processes to reduce the survival and proliferation of infectious pathogens by altering temperature, restriction of essential nutrients, and the activation of an immune reaction. However, once the infection resolves, the febrile response must be tightly regulated to avoid excessive tissue damage. During fever, neurological, endocrine, immunological, and metabolic changes occur that cause an increase in the stable temperature range, which allows the core body temperature to be considerably increased to stop the invasion of the offending agent and restrict the damage to the organism. There are different metabolic mechanisms of thermoregulation in the febrile response at the central and peripheral levels and cellular events. In response to cold or heat, the brain triggers thermoregulatory responses to coping with changes in body temperature, including autonomic effectors, such as thermogenesis, vasodilation, sweating, and behavioral mechanisms, that trigger flexible, goal-oriented actions, such as seeking heat or cold, nest building, and postural extension. Infrared thermography (IRT) has proven to be a reliable method for the early detection of pathologies affecting animal health and welfare that represent economic losses for farmers. However, the standardization of protocols for IRT use is still needed. Together with the complete understanding of the physiological and behavioral responses involved in the febrile process, it is possible to have timely solutions to serious problem situations. For this reason, the present review aims to analyze the new findings in pathophysiological mechanisms of the febrile process, the heat-loss mechanisms in an animal with fever, thermoregulation, the adverse effects of fever, and recent scientific findings related to different pathologies in farm animals through the use of IRT.

El propósito de esta investigación fue estudiar las características macroscópicas de los linfonodos gástricos y mesentéricos, el drenaje linfático y su relación anatómica con las diferentes porciones del aparato digestivo. Debido a que no existen descripciones anatómicas detalladas del tracto gastrointestinal de esta especie, se realizó un estudio complementario para sistematizar los componentes del abdomen. Se estudiaron dos fetos de 7 meses de gestación, con el objeto de precisar la ubicación de los linfonodos gástricos y mesentéricos y realizar un atlas de estos órganos. Luego, se utilizaron 20 llamas (7 machos y 13 hembras) para la realización de radiografías y, para los estudios anatómicos, 10 llamas (8 machos y 2 hembras) de 2 años de edad, con un peso corporal de 98,73 ± 14 kg. Se determinaron la ubicación, forma, peso y tamaño de los linfonodos gástricos y mesentéricos. El drenaje linfático fue estudiado mediante la inyección intranodular de tinta china, de azul de toluidina al 2 % y de la técnica de Gerota modificada. Mediante la linfografía (método de Kinmonth), utilizando Lipiodol ultrafluido inyectable, se obtuvieron imágenes de los linfonodos gástricos, mesentéricos y sublumbares con sus vasos linfáticos. En la llama, los linfonodos tienden a agruparse y presentan una distribución uniforme y constante. Los más pequeños hallados fueron los linfonodos yeyunales, con un peso de 0,46 ± 0,25 g y un tamaño de 13 x 9 x 2 ± 8 x 0,16 x 0,5 cm y el más grande el linfonodo mesentérico craneal, con un peso de 3,74 ± 2,47 g y con un tamaño de 47 x 16 x 13 ± 21 x 6 x 6,5 cm. Las formas ovoide y en V fueron las más frecuentemente observadas en los linfonodos gástricos y mesentéricos, aunque también se encontraron formas alargadas, triangulares con ángulos redondeados, arriñonados, semilunares y esféricos. El colon ascendente presentó unos 700 nódulos linfáticos agregados (placas de Peyer). Todos los vasos linfáticos se unen para formar dos troncos linfáticos que drenan hacia el linfonodo mesentérico caudal ubicado en ventral del ciego.

En la alpaca adulta y en fetos de tercer tercio de gestación, el cuerno uterino izquierdo es más grande que el derecho, además de que presenta ventaja en cuanto a la irrigación. El presente trabajo buscó identificar el momento de diferenciación del tamaño de los cuernos uterinos y los factores anatómicos que influencian esta diferencia, basándose en las relaciones topográficas de éstos con los órganos vecinos y en las características vasculares. Con tal fin, se trabajaron muestras de fetos hembras de diferentes tamaños obtenidos en el Camal Municipal de la Ciudad de Huancavelica, Perú. Los resultados del estudio topográfico indicaron la influencia del desarrollo del estómago y del bazo sobre la forma y la posición del útero, así como la influencia de la flexura del colon sigmoideo sobre el menor tamaño del cuerno uterino derecho. Además, se encontró diferencia significativa entre las medidas del ancho de ambos conductos paramesonéfricos durante el primer tercio de gestación, y entre las medidas del largo y el ancho de los cuernos uterinos en fetos al inicio del segundo tercio gestacional. Macroscópicamente, se observó un patrón vascular similar al de úteros de tercer tercio de gestación y de animales adultos, encontrando una rama comunicante entre las arterias uterinas. Se concluye que la diferenciación del tamaño de los cuernos uterinos es evidente en el inicio del segundo tercio gestacional y que esta condición está influenciada por la posición y el tamaño de las vísceras abdominales, lo que permite un mayor desarrollo del cuerno uterino izquierdo.

Summary South American camelids have several biological, morphological and behavioural adaptations that allow them to live in geographical areas dominated by high altitudes. The liver has hematopoietic functions during the prenatal life, which could be modified in response to the unfavorable habitat. However, there are no previous data on the prenatal development of the liver in these species. In the present work, a study on the macroscopic and microscopic morphology of the liver of the alpaca during ontogeny was performed. Forty-one animals ranging in age from 20 days of embryonic development to adults were studied. Macroscopic and microscopic observations were performed on samples subjected to different techniques. Less than 7-g specimens were studied with stereoscopic magnifying glass. The general characteristics of the prenatal liver are similar to those of other mammals, and the structures related to hematopoietic function follow an ontogenic pattern similar to that of previously studied precocial species. However, there are differences in morphology when compared to descriptions for the Old World camelids, including the absence of relation between the caudate lobe and the right kidney and the lack of interlobular connective tissue.

Objetivos: Comparar los aspectos morfológicos del tracto genital fetal y adulto de la alpaca y la llama. Material y métodos: se realizó el estudio anatómico del útero de cinco fetos de llama y cinco fetos de alpaca, ambos de tercer tercio de gestación, once úteros de alpacas adultas y cinco úteros de llamas adultas. Las muestras de útero se estudiaron por observación anatómica y morfometría. Resultados: Mediante los estudios morfométricos se pudo observar que existía diferencia significativa en el tamaño de ambos cuernos uterinosa favor del lado izquierdo. La relación existente entre el cuerno uterino derecho y el cuerno uterino izquierdo en la alpaca adulta es de 0,79 y en la llama adulta la razón de las medidas es mayor, 0,85 para la longitud y 0,87 para el ancho. En los úteros fetales tanto en llama como en alpaca, se observó que existía diferencia significativa entre el tamaño del cuerno uterino izquierdo y el cuerno uterino derecho a favor del lado izquierdo. Conclusiones: Se concluye que existe similitud entre la forma del útero en los fetos de llama y alpaca en relación al útero de la correspondiente hembra adulta., Objectives: Made a morphologic comparison between fetal uterus and adult uterus in the alpaca and the llama. Material and methods: it was performed anatomical study of five fetal uteri of lama and alpaca, eleven adult alpacas and five lamas uteri. Uterus samples were studied by anatomical observation and morphometry. Results: The results showed that all the samples of adult females had greater development of the left uterine horn. By morphometric studies it was observed that there was significant difference between the size of both uterine horns. The relationship between the right uterine horn and left uterine horn in the alpaca is 0.79 and in the lama, the ratio of the measures is higher, 0.85 for length and 0.87 to the width, in favor of the left uterine horn. In both fetal uterus in the lama as alpaca, was observed that there was significant difference between the size of the left uterine horn and the right uterine horn. Conclusions: exits similarity between the shape of the uterus in the lama and alpaca fetuses in relation to the uterus of the corresponding adult female., Facultad de Ciencias Veterinarias

Summary Morphological studies of the liver of the llama are structural supportive to the clinical practice, surgery and specific diagnostic techniques. The aims of this study were first to determine the location of the organ and the direction of its major axis to project it to the abdominal wall, identifying visible and palpable bony references. Secondly, to characterize and determine anatomical relations of the surfaces, borders and angles of the llama liver, as well as, of its lobulation. Twenty adult llamas of both sexes and two foetuses of 6.5- and 7-month-old were used. Llama liver is a post-diaphragmatic organ located in the cranial abdominal region, in the right hypochondrium, in relationship with the last six ribs. Dorsally, it can exceeds the last (twelfth) rib. Its major axis presents a cranio-ventral bent. Its shape is irregularly triangular. It presents two surfaces (parietal and visceral), three borders (cranial, caudal and ventral) and three angles (dorsal, cranial and caudal).

Se caracterizó la estructura macroscópica y microscópica de las glándulas sexuales anexas del tracto reproductor de la llama macho empleando ocho animales adultos. Se hizo el estudio macroscópico in situ y de órganos aislados, y se colectaron muestras de los órganos para la evaluación histológica. El estudio macroscópico reveló la presencia de dos ampollas en el conducto deferente, ausencia de glándulas seminales, próstata con cuerpo lobulado, istmo y porción diseminada, y dos glándulas bulbouretrales. La dilatación de la porción final de los conductos deferentes sugiere la presencia de las ampollas con característica glandular. El cuerpo prostático tiene apariencia lobular aunque sin una clara delimitación de los lóbulos, y presenta prolongaciones hacia la uretra en forma de pedúnculos, claramente delimitados en la porción diseminada. El peso y las medidas de los lóbulos prostáticos indican que hay mayor masa glandular en el lóbulo izquierdo. Los acinos prostáticos están rodeados de abundante tejido conectivo infiltrado a manera de trabéculas a partir del tejido de la cápsula. Los conductos prostáticos tienen diferentes presentaciones en su desembocadura. Las dos glándulas bulbouretrales son simétricas en peso y tamaño, y están rodeadas de abundante tejido muscular esquelético y poca infiltración de conectivo. Los conductos de las glándulas bulbouretrales desembocan en un divertículo que está dirigido hacia la porción libre del pene. Se concluye que la llama macho presenta ciertas particularidades macroscópicas y microscópicas en relación a la distribución y desembocadura de sus glándulas sexuales anexas. The macroscopic and microscopic structure of the sexual glands of the reproductive tract of the male llama was characterized using eight adult animals. The macroscopic study was done in situ and using extracted organs and samples collected for histological evaluation. The macroscopic examination revealed the presence of two ampoules originating from the vas deferens, the absence of seminal vesicles, and a prostate gland with lobed body, isthmus and a disseminated portion, and two bulbourethral glands. Dilation of the final portion of the vas deferens suggests the presence of ampoules with glandular characteristics. The prostate body has lobular-like shape but without clear delimitations and shows extensions to the urethra in the form of stalks clearly defined in the disseminated portion. The weight and size of the prostatic lobes indicate that there is more glandular mass in the left lobe. The prostatic acini are surrounded by abundant trabeculae connective tissue infiltrated from the capsule tissue. Prostatic ducts have different presentations at their mouths. The two bulbourethral glands are symmetric in size and weight, and are surrounded by abundant skeletal muscle and little connective infiltration tissue. The ducts of the bulbourethral glands drain into a diverticulum that is directed toward the free portion of the penis. It is concluded that the male lama presents certain macroscopic and microscopic particularities in relation to the distribution and mouths of the sexual glands.

The stomach of the new world camelids presents a morphologic structure different from those of the true ruminants. The aim of the present work was to describe the anatomical and histologic features of the stomach of the llama and their relationship with the adjacent structures. Four males llamas were used. Specimens for anatomical studies were fixed by perfusion with 10% formaldehyde. For histology, samples were fixed in Bouin and routinely processed. The anatomical studies showed the proximal compartment located totally in the left abdominal wall. A single right lip, the ventricular furrow, results notorious. The intermediate compartment is kidney-like in shape, with thick walls. The distal compartment is elongated and tubular, located toward ventral-right of the abdominal cavity. Histologicaly, the proximal and the intermediate compartments present areas with and without glands. The nonglandular region is covered by stratified plane epithelium with pleats and without papillae. The glandular area presents pleats whose recesses originate deep pouches, occupied by simple tubular glands, the lining epithelium is cylindrical simple. The distal compartment is completely glandular El estómago de los camélidos sudamericanos presenta una estructura morfológica diferente al de rumiantes verdaderos. El objetivo del presente trabajo fue describir las características anatómicas e histológicas del estómago de la llama y sus relaciones con las estructuras adyacentes. Se utilizaron cuatro llamas machos. Las muestras para estudios anatómicos fueron fijadas por perfusión con formol al 10%. Para histología, las muestras fueron fijadas en Bouin y procesadas rutinariamente. Los estudios anatómicos mostraron que el compartimiento proximal está localizado totalmente en la pared abdominal izquierda. Un labio derecho simple, el pliegue ventricular, resulta notorio. El compartimiento intermedio presenta forma arriñonada con paredes gruesas. El compartimiento distal es elongado y tubular hacia la zona ventral derecha de la cavidad abdominal. Histológicamente, los compartimientos proximal e intermedio presentan áreas con y sin glándulas. La región no glandular está cubierta por epitelio plano estratificado con pliegues y sin papilas. El área glandular presenta pliegues cuyos recesos originan profundos sacos, ocupados por glándulas tubulares simples, tapizadas por epitelio cilíndrico simple. El compartimiento distal es completamente glandular

Se observó la estructura macro y microscópica del hígado de 6 llamas adultas (Lama glama), 4 machos y 2 hembras. El hígado se ubica en la región abdominal craneal, a la derecha del plano mediano. Carece de vesícula biliar y el conducto hepático se une al conducto pancreático mayor, a unos 3 cm del duodeno, formando el conducto hepato-pancreático, el cual desemboca mediante el trayecto intramural en la segunda curva de la ese sigmoídea del duodeno. En los lobulillos hepáticos, el tejido conectivo de soporte es escaso, se halla limitado al espacio porta. Los estudios morfológicos brindan un soporte estructural para la realización de técnicas de diagnóstico específicas de este órgano, como por ejemplo, la biopsia hepática The objetive of this study was the description of the macroscopic characteristics of the liver: position, anatomic relationships, peritoneal folds, lobes, irrigation, innervation, lymphatic drainage and biliary tree.The histologic description was carried out under the classic morphologic organization model (classic hepatic lobule). The macroscopic and microscopic structure of the liver in 6 adult llamas (4 males and 2 females) was observed. The liver was situated in the cranial abdominal region, to the right of the medial plane.The gall bladder was abscent in llamas.The bile duct was joined to the pancreatic duct at 3 cm from the duodenum forming the hepato-pancreatic duct, which empties by means of the intramural course in the second curvature of the sigmoid flexure of the duodenum. The hepatic lobules was limited by connective tissue near the portal area. Morphological studies offer a structural support to the specific diagnostic techniques of this organ, for example, liver biopsy

La estructura de las visceras y glandulas anexas del aparato digestivo de los camelidos sudamericanos, muestran diferencias morfologicas con relacion a otros rumiantes. Los estudios macroscopicos realizados, nos permitieron observar que en los camelidos sudamericanos la ampolla duodenal y el conducto hepatopancreatico (CHP) presentan caracteristicas particulares que le confieren una marcada diferencia con los bovinos domesticos, al presentar una desembocadura comun de ambos conductos. Los estudios se realizaron mediante tecnicas histologicas de rutina y por medio de histoquimica de lectinas. El conducto biliar se une al pancreatico a unos 3 cm del duodeno, formando el CHP que desemboca sobre el duodeno en el pliegue duodenal, bien visible, con direccion caudal a favor del transito intestinal, recorriendo 2 cm por dentro de la mucosa intestinal. Presenta un orificio terminal en forma de bisel, ubicado a unos 40 cm del piloro. No se observa conducto pancreatico accesorio. El CHP se halla tapizado por epitelio cilindrico simple, sin celulas caliciformes. Sobre el pliegue duodenal se observa mayor desarrollo glandular, aumentando su espesor. El epitelio cilindrico es mas alto, mas acidofilo y se invagina formando glandulas rodeadas de tejido conectivo. Las glandulas son tubulares con celulas acidofilas y basofilas, ricas en mucopolisacaridos. Para caracterizar los glicoconjugados, se utilizo una bateria de siete lectinas (Con A, UEA-1, SBA, DBA, PNA, RCA-1, WGA). En las celulas epiteliales de la mucosa, los glucoconjugados mas destacados presentes son la N-acetilglucosamina y N-acetilgalactosamina dado que dieron marcada reactividad con las lectinas WGA y SBA. La N-acetilglucosamina y N-acetilgalactosamina son aminoazucares que suelen encontrarse como carbohidratos estructurales. En las glandulas de la mucosa del CHP se observo que las celulas presentan N- acetilgalactosamina y en menor proporcion N-glucosamina

Los terneros comienzan a rumiar a las 2 ó 3 semanas de edad, pasando de lactante a rumiante de acuerdo a la influencia de estímulos que recibe de la dieta.(BRODY, 1945; SWANSON, 1960 y National Research Council, 1989). El objetivo del presente trabajo fue evaluar los cambios en el desarrollo morfohistológico del estómago de terneros lactantes, alimentados con dos sustitutos (tratamientos) que difieren en su composición. Tratamiento "A" consistió en: derivados de la leche (dl) 65%, fibra detergente neutro (FDN) 1,75% y almidón (al) 24,6%. Tratamiento "B": dl 50%, FDN 6,5% y al 19,2%. Se trabajó con un total de 18 terneros machos (9 en cada tratamiento), de raza Holando Argentino a los que se les suministró una dieta consistente en 240g de sustituto en cada una de las 2 tomas diarias durante 45 días, concentrado "ad libitum", disponibilidad de forraje fresco y agua, durante 50 días. Para la evaluación anatómica, se muestrearon 6 terneros, seleccionados para cada fecha y tratamiento, a los días 18-41 y 50, tomando en cada una de ellas un ternero de cada tratamiento. La evaluación consistió en efectuar mediciones de capacidad, longitud, peso vacío, peso relativo de la digesta de los distintos compartimentos del estómago. Utilizando el test de Análisis de Varianza (ANDEVA), no se observaron diferencias (P > o = 0,05) en peso vivo (PV) entre dietas para las tres fechas, observándose una tendencia de mayor PV en la dieta "A". En cambio, en la capacidad del contenido del retículo, como en el espesor del epitelio del mismo, se evidenciaron diferencias significativas (P< 0,05) con R² 0,75 y 0,8 respectivamente. Debido a la falta de repeticiones del ensayo y al efecto tiempo, los resultados sólo tienen valor descriptivo. Si bien a temprana edad (18 días) se evaluó mayor capacidad del rumen en terneros alimentados con el sustituto de menor calidad "B", a los 50 días, se observa un incremento en el desarrollo del estómago en los alimentados con sustituto de mayor calidad "A". Al incorporar al sustituto lácteo mayor % de derivados de la leche, se favorece la capacidad anatómica del estómago, lo cual permitía a los terneros convertirse en rumiantes más tempranamente. Para la evaluación histológica se muestrearon seis terneros seleccionados para cada fecha y tratamiento a los días 18, 41 y 50 días. Las muestras fueron fijadas en formol bufferado al 10%, luego procesadas por técnicas histológicas de rutina y los cortes coloreados mediante la tinción hematoxilina/eosina. Para el análisis de los cortes se utilizó un microscopio Olympus, con ocular graduado y objetivo de 4x. Se efectuaron mediciones de la longitud de las papilas, espesor del epitelio y presencia de células vacuoladas o tumefactas. Si bien, a temprana edad (18 días) se observa una mayor longitud en las papilas de la mucosa del rumen en terneros alimentados con el sustituto "A", a los 50 días esta relación cambia en favor de los alimentados con sustituto de menor calidad "B". A los 50 días de tratamiento el desarrollo en la longitud de las papilas de red y omaso, presenta una tendencia a incrementar en favor del tratamiento "A" The calves begin to ruminate to the 2 or 3 weeks of age, passing of lactante to ruminant according to the influence of stimuli that its receives from the diet. (BRODY, 1945; National Research Council, 1989; SWANSON, 1960). The objective of the present work was to evaluate the changes in the development morfohistologic of the stomach of calves lactantes fed with two substitutes (treatment) that differ in its composition, treatment "A": derived of the milk (dl) 65%, fiber neuter detergent (FDN) 1,75% and starch (to the) 24,6%, treatment "B": dl 50%, FDN 6,5% and to 19,2%. One worked with a total of 18 male calves (9 in each treatment) of race Holando to those that were given a consistent diet in 240 g. of substitute for taking, in 2 daily takings during 45 days, concentrated "ad libitum", readiness of fresh forage and it dilutes during the 50 days. For the anatomical evaluation the samples was obtained the 6 calves, selected for each date and treatment, to the days 18 - 41 and 50 taking in each one of them a calf of each treatment. The evaluation consisted on making mensurations of capacity, longitude, empty weight, relative weight of the digesta of the different compartments of the stomach. The use of the variance analysis ANOVA, the differences were not observed (P = 0,05) in weight I live (PV) among diets for the three dates, being observed a tendency of more PV in the diet "A". On the other hand in the capacity of the content of the reticulum, like in the thickness of the epithelium of the same one, significant differences were evidenced (P

Reproductive studies usually utilizes measurement of progesterone in various fluids such as plasma, serum or milk. It has been shown that progesterone concentrations in bovine whole blood decrease proportionally to: i) the time elapsed between the collection of the sample and the separation of plasma or serum from the erythrocytes and ii) the temperature of storage during this period (Breuel et al, 1988, Pulido et al. 1991). The addition of anticoagulants cause a more rapid decline in progesterone concentrations (Wiseman et al. 1982). In equine, porcine and canine blood samples storage time and temperature has a negligible effect on progesterone concentrations (Wiseman et al. 1982; Oltner & Edqvist 1982). Cordero et al. (1991) working with llama and alpaca whole blood, treated with EDTA as anticoagulant, reported a slight progesterone metabolization in alpaca plasma, but not in llama plasma.