Organogenesis of the Opercular Apparatus in Salvelinus fontinalis (Mitchill)

1963 ◽  
Vol 20 (2) ◽  
pp. 347-372 ◽  
Author(s):  
L. R. Day

The opercular fold in Salvelinus fontinalis (Mitchill) begins as a bulging, outward and backward, of the undifferentiated dorsally-packed mesenchymal tissue of the hyoid arch in embryos of 6.0–6.5 mm total length. From 6.5 to 9.0 mm, backward growth takes place although no gill arches are covered. The epithelium of the opercular anlage is 2- to 3-layered laterally and 1- to 2-layered with smaller nuclei medially. From 9.0 to 14.0 mm, i.e. hatching, the membranous lateral opercular and ventral branchiostegal portions extend posteriorly to cover the four gill arches. Ossification commences in the opercle, the jaws and the pectoral girdle. The epithelium which has scattered goblet cells is 3- to 4-layered antero-laterally, 1- to 2-layered postero-laterally and one cell in thickness medially. From 14.0 to 30.0 mm length ossification of the skeletal elements of the opercular apparatus takes place. The musculature of the operculum is complete at hatching.

Author(s):  
J. Matallanas

The hyoid arch and branchiostegal rays of Paraliparis leptochirus (Pisces: Liparidae) and of Paraliparis murieli are described for the first time. The restoration of the validity of Eutelichthys Tortonese on the basis of the presence of only five branchiostegal rays in P. leptochirus, its type species, is proposed. Paraliparis murieli has, as the other Paraliparis spp., a hyoid arch with six branchiostegal rays. The endochondral pectoral girdle of P. leptochirus, P. murieli and P. hystrix is described for the first time, and some data about the girdle of P. edwardsi are given. Differences between P. hystrix and P. murieli, described simultaneously, and between P. murieli and P. australis are established.


2020 ◽  
Vol 33 (1) ◽  
pp. 69-75
Author(s):  
Cecilia M. Riestra ◽  
Jorge E. Perez Comesaña † ◽  
Karina A. Arias ◽  
Leando L. Tamini ◽  
Gustavo E. Chiaramonte

Predictive regression equations were generated to estimate total length of the Argentine seabass (Acanthistius patachonicus) using skull and pectoral girdle bones, specific body, and otolith lengths. Regressions of skull and pectoral girdle bones, specific body and otolith lengths were all statistically significant. Generating regressions between specific bones and external characteristics of the body meaningfully increases the ability to analyse the information obtained from studies of stomach contents of predator fish from the Southwestern Atlantic Ocean.


2020 ◽  
Vol 5 (2) ◽  
pp. 504
Author(s):  
Matthias Omotayo Oladele ◽  
Temilola Morufat Adepoju ◽  
Olaide ` Abiodun Olatoke ◽  
Oluwaseun Adewale Ojo

Yorùbá language is one of the three main languages that is been spoken in Nigeria. It is a tonal language that carries an accent on the vowel alphabets. There are twenty-five (25) alphabets in Yorùbá language with one of the alphabets a digraph (GB). Due to the difficulty in typing handwritten Yorùbá documents, there is a need to develop a handwritten recognition system that can convert the handwritten texts to digital format. This study discusses the offline Yorùbá handwritten word recognition system (OYHWR) that recognizes Yorùbá uppercase alphabets. Handwritten characters and words were obtained from different writers using the paint application and M708 graphics tablets. The characters were used for training and the words were used for testing. Pre-processing was done on the images and the geometric features of the images were extracted using zoning and gradient-based feature extraction. Geometric features are the different line types that form a particular character such as the vertical, horizontal, and diagonal lines. The geometric features used are the number of horizontal lines, number of vertical lines, number of right diagonal lines, number of left diagonal lines, total length of all horizontal lines, total length of all vertical lines, total length of all right slanting lines, total length of all left-slanting lines and the area of the skeleton. The characters are divided into 9 zones and gradient feature extraction was used to extract the horizontal and vertical components and geometric features in each zone. The words were fed into the support vector machine classifier and the performance was evaluated based on recognition accuracy. Support vector machine is a two-class classifier, hence a multiclass SVM classifier least square support vector machine (LSSVM) was used for word recognition. The one vs one strategy and RBF kernel were used and the recognition accuracy obtained from the tested words ranges between 66.7%, 83.3%, 85.7%, 87.5%, and 100%. The low recognition rate for some of the words could be as a result of the similarity in the extracted features.


Author(s):  
А.А. Коваленко ◽  
Г.П. Титова ◽  
В.К. Хугаева

Оперативное лечение различных заболеваний кишечника сопровождается осложнениями в виде нарушений микроциркуляции в области анастомоза кишки. Ранее нами показана способность лимфостимуляторов пептидной природы восстанавливать нарушенную микроциркуляцию, что послужило основой для настоящего исследования. Цель работы - оценка влияния стимуляции лимфотока в стенке кишки на процессы восстановления микроциркуляции, структуры и функции тонкой кишки в области оперативного вмешательства. Методика. В экспериментах на наркотизированных крысах (хлоралгидрат в дозе 0,6 г/кг в 0,9% растворе NaCl) моделировали различные поражения тонкой кишки (наложение лигатуры, перевязка 1-3 брыжеечных артерий, перекрут петли кишки вокруг оси брыжейки, сочетание нескольких видов повреждений). Резекция поврежденного участка через 1 сут. с последующим созданием тонкокишечного анастомоза завершалась орошением операционного поля раствором пептида-стимулятора лимфотока (40 мкг/кг массы животного в 1 мл 0,9% раствора NaCl). На 7-е сут. после операции проводили гистологическое исследование фрагмента кишки в области анастомоза. Результаты. На 7-е сут. после резекции у выживших животных (летальность вследствие кишечной непроходимости составляла 30%) имеют место морфологические признаки острых сосудистых нарушений стенки кишки, изменений кровеносных и лимфатических микрососудов, интерстициальный отек всех слоев стенки кишки, дилатация просвета кишки, повреждение всасывающего эпителия ворсин с истончением щеточной каемки клеток, морфологические признаки гиперфункции бокаловидных клеток. Использование лимфостимулятора пептидной природы после операции увеличивало выживаемость животных на 24%. У части животных отмечалось уменьшение расширения просвета кишки, у других практически полная его нормализация. Восстанавливалась форма кишечных ворсин и распределение бокаловидных клеток. Отсутствовали признаки внутриклеточного и межмышечного отека. Отмечено умеренное полнокровие венул. Заключение. Использование лимфостимулятора при хирургическом лечении кишечной непроходимости увеличивает выживаемость животных на 24% по сравнению с контролем, способствует более раннему восстановлению структуры и функции тонкой кишки. Полученные результаты свидетельствуют о перспективности использования стимуляции лимфотока при операциях на кишечнике. Surgical treatment of bowel diseases is associated with complications that cause microcirculatory disturbances in the anastomosis area and may lead to a fatal outcome. This study was based on our previous finding that peptide-type lymphatic stimulators are able to restore impaired microcirculation. The aim of this work was stimulating the lymph flow in the intestinal wall to facilitate recovery of microcirculation, structure and function of the small intestine in the area of surgical intervention. Methods. In experiments on anesthetized rats (0.6 g/kg chloral hydrate in 0.9% NaCl), various small bowel lesions were modeled (bowel ligation, ligation of 1-3 mesenteric arteries, gut torsion, combination of several lesion types). In 24 h, the damaged area was resected, and a small intestine anastomosis was creased. The surgery was completed with irrigation of the operative field with a solution of lymph flow stimulating peptide (40 мg/kg body weight in 1 ml of 0.9% NaCl). A gut fragment from the anastomosis area was examined histologically on day 7 after the surgery. Results. On the 7th day after removing the intestinal obstruction, the surviving animals (lethality 30%) had morphological signs of acute vascular disorders in the intestinal wall; changes in blood and lymphatic microvessels; interstitial edema of all intestinal wall layers; dilatation of the intestinal lumen; damage to the absorptive epithelium of villi with thinning of the brush border, and hyperfunction of mucous (goblet) cells. The use of the peptide after surgery increased the survival rate of animals by 24% and provided a smaller dilatation of the intestinal lumen in some animals. In other animals, the lumen recovered. The shape of intestinal villi and distribution of goblet cells were restored. Signs of intracellular and intermuscular edema were absent. Moderate venular congestion was noticed. Conclusion. Using the lymphatic stimulator in surgical treatment of intestinal obstruction increases the survival rate of animals by 24% compared to the control, facilitates earlier restoration of the small intestine structure and function. The obtained results indicated the effectiveness of lymphatic stimulation in intestinal surgery.


Author(s):  
V. Turlyun

The analysis of some herds of imported cattle under the conditions of Russian farms had been shown that the genetic potential of imported cattle in many farms has being realized only by 57 %, with the output of up to 50 % of the cattle during the first 2 years. The reason for this is the discrepancy between the conditions of the biological needs of animals. In this regard, the study of factors that affect the provision of comfortable conditions for animals plays an important role. This is especially true for Holstein animals, which are more susceptible to various diseases. In accordance with the technological solutions used in modern large complexes, the loose housing method of maintenance is mainly used. This method allows the animal to move freely, providing access to the consumption of water and feed, as well as timely rest. This determines the importance of the requirements for the size of the boxes for the rest of animals, which should ensure dryness and cleanliness in the process of resting cows, prevent damage to animals, as well as the ability of other animals to displace each other. The crossbars should not interfere with the free movement of the cow in the process of lowering to the floor and getting up due to their flexibility. The dimensions of the boxes should be made taking into account the measurements of the animals’ torso, as well as the amplitude of movement in the process of lowering and rising. The purpose of the research was to study the size of boxes and their compliance with the biological needs of highly productive imported cattle. An analysis of the compliance of conditions for housing highly productive cattle of Canadian and Australian origin with their biological needs under the conditions of a mega farm has been presented in the paper. Calculation on the basis of measurements of animals has been shown that animals of the Canadian selection require boxes with a total length of at least 279 cm, Australian – 271 cm. The difference with the required width of the box has been also established. For the group of cows of Canadian selection it should be at least 120 cm, for the Australian – 114 cm. Research results have been shown that the discrepancy in the design of boxes for comfortable rest of animals is a deterrent to the realization of their genetic productive potential.


2009 ◽  
Author(s):  
◽  
Débora Fabiana Bubach

El objetivo de este trabajo fue estudiar algunos elementos traza y mayoritarios en músculo e hígado de peces de lagos de la Patagonia Norte Cordillerana para brindar información sobre los niveles de base en relación a la distribución global de elementos, y efectos locales relacionados con la variabilidad interespecifica en un mismo ambiente y espacial en una misma especie entre las distintas cuencas. Para lo cual, en el primer caso, se compararon las concentraciones elementales en los peces cordilleranos patagónicos que incluyeron salmónidos: Salmo trutta (trucha marrón), Oncorhynchus mykiss (trucha arco iris), Salvelinus fontinalis (trucha de arroyo), un percíctido: Percichthys trucha (perca de boca chica) y un silúrido: Diplomistes viedmensis (bagre aterciopelado) con grupos taxonómicos similares de áreas remotas y con impacto antrópico de distintas regiones del mundo. En el segundo caso, se evaluó la variabilidad interespecífica de la concentración de los elementos en los lagos Nahuel Huapi y Moreno por estar próximos y conectados, y fundamentalmente por la variedad y abundancia de especies de peces. La variabilidad espacial de la composición elemental de los peces en las distintas cuencas relacionadas con diversos factores ambientales como el basamento geológico y el impacto antrópico, se evaluó en la trucha arcoíris que está ampliamente distribuida en los distintos lagos, de vertiente atlántica como el Traful, Espejo Chico, Nahuel Huapi y Moreno, y de pendiente pacífica como Guillelmo, Rivadavia y Futalaufquen.


2019 ◽  
Author(s):  
Kiersten K. Formoso ◽  
◽  
Michael B. Habib ◽  
David J. Bottjer

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