The superorder Galeomorph comprises the orders Heterodontiformes, Orectolobiformes, Lamniformes, and Carcharhiniformes. Recent morphological and molecular support that it is a monophyletic taxon. The phyletic relationship within the Galeomorphi are also well resolved. However, only few morphological characters of the mandibular and hyoid muscles have been employed, and a detailed description of these muscles and their variations may contribute new interpretations of homology and to the discussion of different hypothesis of intrarelationships. This paper provides a detailed description of mandibular and hyoid arch muscles in galeomorph sharks, within a comparative elasmobranch framework, with the objective to discuss putative homologies that may elucidate our understanding of galeomorph evolution. Twenty-eight galeomorph species were dissected, described, illustrated and compared with other elasmobranchs and with data from the literature. The Galeomorphi are supported as monophyletic by presenting the m. levator labii superioris attached directly to the neurocranium, different from the attachment through a tendon in basal squalomorphs. Heterodontiformes and Orectolobiformes share particular variations in the position and insertion of the m. levator labii superioris and the presence of a well-defined m. levator hyomandibulae. Lamniformes and Carcharhiniformes show similar patterns in the position and attachment of the m. levator labii superioris, subdivision of the m. adductor mandibulae, and the presence of an almost indivisible m. levator hyomandibulae and m. constrictor hyoideus dorsalis, similar to the condition, albeit independently, in basal squalomorphs. No specific mandibular or hyoid arch muscle character was found to support the clade composed of Orectolobiformes, Lamniformes, and Carcharhiniformes, as advocated by recent phylogenetic analyses.
The order Hexanchiformes currently comprises two families, Chlamydoselachidae (frilled sharks) and Hexanchidae (six- and seven-gill sharks), but its monophyly and relationships with other elasmobranchs are still discussed. Previous studies of hexanchiforms addressing these issues were based mainly on external morphology, teeth, skeletal features, and molecular data, whereas the employment of characters derived from variations in muscles has not been significantly explored. Dissections of four species of Hexanchiformes (including Chlamydoselachus anguineus) are reported here describing the mandibular (musculus adductor mandibulae dorsalis, m. adductor mandibulae ventralis, m. levator labii superioris, m. intermandibularis, and m. constrictor dorsalis) and hyoidean (m. constrictor hyoideus dorsalis and ventralis) arch muscles. Our results provide new data concerning the relationships of hexanchiforms to other elasmobranchs. The m. adductor mandibulae superficialis is described and illustrated in C. anguineus, contradicting previous accounts in which is was considered absent. The anteroposterior orientation of the m. adductor mandibulae superficialis in Chlamydoselachus is similar to the pattern found in hexanchids, squaloids, and hypnosqualeans (including batoids), suggesting it was secondarily lost in Echinorhinus. This muscle therefore provides further support for the inclusion of the Chlamydoselachidae and Hexanchidae in the Squalomorphi, and not basal to all other elasmobranchs or nested within an all-shark collective, as has been previously proposed. However, the m. adductor mandibulae superficialis originating at the jaw joint and with an aponeurotic insertion in hexanchids, squaliforms, and hypnosqualeans, may be a separate derived feature uniting these taxa. The insertion of the m. constrictor dorsalis is restricted to the postorbital articulation in hexanchids, whereas it extends farther anteriorly in C. anguineus. The insertion of the m. constrictor hyoideus dorsalis solely on the palatoquadrate is found exclusively in the Hexanchidae. We conclude that no specific pattern of mandibular or hyoid arch muscles support the monophyly of hexanchiforms (i.e., including Chlamydoselachus).
The fermentative, microbiological and nutritional dynamics of bovine colostrum fermented under anaerobic conditions at different temperatures is provided. Colostrum was homogenized and stored in PET bottles in anaerobic conditions and incubated at controlled temperature (32.5 ± 1°C or 22.5 ± 1°C) or at room temperature (17.4 - 21.5ºC) and opened after 0, 1, 7, 14, 21, 28 and 35 days to determine fermentative and nutritional parameters and bacteria, yeast and mold counts. Further, pH rates showed significant variations during the fermentation period (p < 0.0001), with colostrum stored at 32.5°C, exhibiting the lowest rates and significant reduction during the first days. Titratable acidity and lactic acid concentration showed increasing rates and LAB development was intense, especially at high temperatures. After 35 days, about 50% of total nitrogen became non-protein N and casein fraction was reduced to 0.66% of total nitrogen. Lactose decreased during fermentation and fat concentrations were not affected by temperature. Results suggested that the temperature at which the colostrum was fermented directly influenced the speed and intensity of microbial population development and degradation of the main nutritional parameters, such as casein and lactose.
RESUMO Vinte bezerros mestiços da raça Holandês x Jersey, distribuídos em blocos completos casualizados, foram utilizados para determinar o efeito do fornecimento de probiótico de bactérias ruminais sobre o desempenho e os parâmetros sanguíneos de bezerros leiteiros em sistema de desaleitamento precoce. Os animais foram submetidos ao tratamento controle ou ao fornecimento via oral de 2g de probiótico/dia durante o aleitamento. Os bezerros receberam 6 litros de sucedâneo lácteo por dia divididos em duas refeições diárias e foram desaleitados de forma gradual na 6ª semana de vida, entretanto, as variáveis foram coletadas até a 10ª semana. O consumo de concentrado inicial e o escore fecal foram registrados diariamente. Semanalmente foram realizadas pesagens e medidas corporais como, altura de cernelha, largura de garupa e perímetro torácico. Foram realizadas colheitas de sangue nas semanas, 2, 4, 6, 8 e 10, 2h após o primeiro aleitamento, para determinação de concentrações plasmáticas de glicose, proteína total, albumina, β-hidroxibutirato e cortisol. A suplementação de probiótico não afetou o consumo de concentrado, o peso, o ganho de peso, e as medidas corporais dos animais. Não houve efeito sobre o escore fecal entre os tratamentos. Os parâmetros sanguíneos não foram alterados em resposta ao fornecimento do probiótico, apenas a concentração de cortisol, que foi maior nos animais suplementados. O fornecimento de probiótico de bactérias ruminais não favorece o desempenho e o metabolismo de bezerros leiteiros em sistema de desaleitamento precoce.
The aim of the present study was to evaluate the effect of replacing corn grain with citrus pulp (CSP) in the starter concentrate on performance and metabolism of dairy calves. Twenty-four individually housed Holstein calves were blocked according to birth date and weight and fed one of the following concentrates: (1) concentrate containing 64% corn and 0% CSP (0CSP); (2) concentrate containing 32% corn and 32% CSP (32CSP); and (3) concentrate containing 0% corn and 64% CSP (64CSP). Animals were fed 4 L of milk replacer daily (20% crude protein, 16% ether extract) divided in two meals (at 0700 hours and 1800 hours). The starter feed and water were provided ad libitum. Starter intake and faecal score were monitored daily. Bodyweight and measurements (withers height, hip width and heart girth) were recorded weekly. Blood samples were collected weekly, and ruminal fluid samples at 4, 6 and 8 weeks of age, 2 h after the morning feeding. After 8 weeks, animals were harvested to evaluate the development of the proximal digestive tract. Concentrate composition had no effect (P > 0.05) on concentrate intake, weight gain, bodyweight, body measurements, and faecal score. However, there was a lower concentration of ruminal butyrate (P < 0.05) in animals receiving 0CSP than in those fed the starter containing CSP. The 0CSP concentrate resulted in a lower (P < 0.05) total weight of the proximal digestive tract, weight of the reticulum–rumen and weight of the omasum than did the other concentrates. The length of the rumen papillae was the greatest (P < 0.05) in 32CSP-fed animals. However, papillae area in animals fed 32CSP concentrate was larger (P < 0.05) than that in 0CSP- and 64CSP-fed animals, with no difference observed between these latter two treatments. However, 0CSP-fed animals showed a higher proportion of abomasum than did the animals fed 32CSP and 64CSP concentrates. The replacement of 50% or 100% of corn by CSP in the starter feed of dairy calves did not affect performance and probably contributed to the better development of the proximal digestive tract.
Botulism is a febrile disease, fatal in most cases, which affects the muscles of locomotion, chewing, and swallowing, as well as the diaphragm and intercostal muscles, causing flaccid paralysis and respiratory arrest. In bovines, the etiology is due to the ingestion of neurotoxins types C and D formed by the bacterium Clostridium botulinum in an animal or vegetal substance, during decomposition. Vaccination is one of the most effective prophylactic means to prevent this disease. In this study, an outbreak of botulism was evaluated in a feedlot with 6,300 finishing cattle, wherein 25 died as a consequence of contracting this disease. The economic losses resulting from the deaths were analyzed, and economic analysis was conducted, involving the estimated cost of vaccination for the whole herd under risk, with the objective of evaluating whether this prophylactic practice is a viable action plan. The financial loss due to the deaths resulting from botulism in the case studied was found to be R$55,560.00, equivalent to 0.39% of the total monetary value of the herd. The cost of immunizing the entire herd under risk was 14.06% (for toxins exclusive to toxins C and D) and 22.22% (for polyvalent vaccines against clostridiosis) of the financial loss incurred as a consequence of the recorded deaths. It was concluded that botulism is a disease that can cause a significant economic impact on intensive livestock production systems, and that vaccination is an economically viable prophylactic action if performed with adequate sanitary planning.
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