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The aim of our study was to evaluate the effect of propolis on mortality of fish eggs due to mycosis, to study its efficacy on the fish growth rate and to analyze the histochemical and ultrastructural characteristics of muscle fibres. We evaluated the muscular development of fish in two different experimental conditions: traditional feeding and feeding with addition of propolis (groups A and B, respectively). The study was carried out on two species of teleosts bred in Italy, Oncorhynchus mykiss (rainbow trout) and Salmo trutta (brown trout). The use of propolis reduced mortality of fish eggs. The muscles were stained for myosin ATPase and succinic dehydrogenase to evaluate fibre type. The area, maximum and minimum diameter for each fibre type in relation to the body length were measured. The animals fed propolis showed a more rapid muscular growth compared to control fed the standard diet. Fibres were larger in the Salmo trutta than in the Oncorhynchus mykiss in both groups. In fish of A group, myotomal muscle, the presence of giant fibres and index of environmental stress was noticed. This type of study is valuable in order to extend the use of propolis as an antifungal agent and a natural product that can improve fish farming.

The aim of the present experiment was to determine the effect of sex and age on histochemical and morphometric characteristics of muscle fibres (myocytes) in lambs born by single, twin, triplet and quadruplet birth. Thirty lambs were slaughtered at 60 days of age; thirty were weaned at 60 days and fed until 120 days with flakes (60%) and food supplements, and then slaughtered. Muscle tissues were obtained from two muscles, namely m. semitendinosus and m. longissimus dorsi of all lambs. For each fibre type, area perimeter and diameter (maximum and minimum) were measured and slow-twitch oxidative fibres, fast-twitch glycolytic fibres, fast-twitch oxidative-glycolytic fibres were histochemically differentiated. The muscles were stained for myosin ATPase, and succinic dehydrogenase. At 60 days, females had fibres larger than males, whereas the opposite was observed at 120 days. Besides, at 60 days, the lambs born by single birth had fibres larger than those born by multiple birth, whereas the opposite was observed at 120 days. Single lambs were heavier than twin lambs and multiple lambs. Fast-twitch glycolytic fibres had the largest size, followed by slow-twitch oxidative and fast-twitch oxidative glycolytic fibres. The dimensions of fibre types in m. longissimus dorsi were larger than in m. semitendinosus (P < 0.001).These muscle fibre characteristics are thought to be important factors influencing meat quality, which is often related to metabolic and contractile properties as determined by the muscle fibre type distribution.

Little is known about the Casertana pig. The aim of this study was to evaluate the effect of sex on histochemical and morphometrical characteristics of muscle fibres (myocytes) in this pure breed and to verify the presence of giant fibres as well as vascularity of the muscle. Finally, maximum shortening velocity and isometric tension were measured in single muscle fibres. Sixteen Casertana pigs (8 males, 8 females) from a farm in Campania (Italy) were slaughtered at one year of age. Muscle tissues were obtained from psoas minor, rhomboideus and longissimus dorsi. Myofibres were stained for myosin adenosine triphosphatase, succinic dehydrogenase, and α-amylase-periodic acid schiff. For all fibre types, the area and perimeter were measured. Slowtwitch oxidative fibres, fast-twitch glycolytic fibres and fast-twitch oxidative-glycolytic fibres were histochemically differentiated; an image-analyzing system was used. The results showed significant differences between the sexes in the size of all three fibre types. The psoas minor muscle had a high percentage of slow-twitch oxidative fibres and contained more capillaries per fibre and per mm2 than rhomboideus and longissimus dorsi, in which fast-twitch glycolytic fibres dominated. The cross-sectional area of all fibre types was larger in longissimus dorsi than in rhomboideus and psoas minor muscles; the giant fibres were present in the longissimus dorsi muscle only. Besides, isometric tension values were higher in fast-twitch glycolytic fibres than in the other ones. Variations in fibre type composition may contribute to meat quality.

A description of the pelvic limb musculature of ostrich (Red Neck) is given. Muscle tissues were obtained from muscle iliotibialis lateralis pars preacetabularis, muscle femorotibialis medius and muscle fibularis longus. The histochemical results revealed the presence of two types of fibres: slow-twitch fibres (type I) and fast-twitch intermediate fibres (type IIA). A higher incidence of type I compared to type IIA fibres in muscle iliotibialis lateralis pars preacetabularis and muscle femorotibialis medius was noticed. The immunohistochemical results revealed that in this species calpain/calpastatin system was localized in various parts of the muscles, although μ-calpain and m-calpain totally disappeared at 4 days post-mortem. Calpastatin and p-94 were present during all the period considered (0, 2 days, 4 days and 6 days post-mortem). In this study changes in enzymatic activities of μ and m-calpain were observed, particularly the activity of μ and m-calpain decrease rapidly during post mortem storage.

A staining procedure used for simultaneously determining three different fibre types in single sections bovine, porcine or ovine skeletal muscle was modified for use with Ostrich skeletal muscle. The muscle fibres of Gastrocnemius pars externa, Tibialis cranialis caput tibiale, Tibialis cranialis caput femorale and Fibularis longus tendo caudalis were studied. The histochemical results revealed the presence of three types of fibre only in the Gastrocnemius pars externa muscle: fast-twitch glycolytic fibres (FG), fast-twitch oxidative glycolytic fibres (FOG) and slow-twitch oxidative fibres (SO), while in the other muscles the FG fibres were absent. The percentage distribution of fibres types showed a higher incidence of SO fibres compared to FOG fibres in Tibialis cranialis caput femorale and Tibialis cranialis caput tibiale muscles, while it was opposite in the case of the Fibularis longus tendo caudalis muscle. In the Gastrocnemius pars externa muscle the FG fibres outnumber the other fibres, followed by the SO and FOG fibres. The results of the analysis of variance show significant interaction between muscle · fibre type for every morphometric parameter evaluated. Differences about value of fibres area exists between Tibialis cranialis caput femorale and Fibularis longus tendo caudalis muscles. Both fibre types in Tibialis cranialis caput tibiale muscle have mean values of transversal section area smaller than Tibialis cranialis caput femorale. The other morphometric parameters show a similar trend. The Gastrocnemius pars externa muscle presents similar dimensions of muscle fibres for the FG and FOG types, and significantly smaller for the SO type.

A differential sister chromatid exchange (SCE)/cell response was observed between phytohemagglutinin (PHA) and pokeweed (PKW) stimulated blood lymphocytes of goat (Capra hircus L) exposed to final concentrations of 0.1, 0.25, 0.5, 1, 2.5 and 5 pg/mL of BUdR. At 0.1 !g/mL of BUdR, the two mitogens gave very similar SCE/cell responses: the SCE mean values were 3.17 ! 1.93 for PHA and 3.28 ! 1.76 for PKW, and the frequency distributions fit very well the Poisson probability function with both mitogens. For 0.25 vg/mL and increasing BUdR concentrations, SCE/cell rates for pokeweed mitogen were significantly higher than those of PHA. At 5 4g/mL of BUdR, the SCE/cell response was 8.68 ! 3.24 for PKW and 6.96 ! 3.45 for PHA, and the difference was statistically significant (P = 0.0001); for both mitogens the SCE/cell frequency distributions fit the Poisson probability function only by adopting a Poisson ’mixture’ model, which takes into account the presence of two different subpopulations of cells.

Neural receptors of the porcine clitoris were examined using light and electron microscopy. Perfusion with ink allowed study of the unique vascular arrangement associated with the genital corpuscles. Sensory nerve-endings were generally rounded and formed a morphologically and structurally characteristic unit. They were composed of a network of primarily non-myelinated nerve fibers and flat cells. Between these structures, isolated small blood vessels were embedded amongst collagen fibers and amorphous material. An external capsule of variable thickness always surrounded the structures. A complex arrangement of vessels in the center of the capsule was formed by a subpapillary mesh. The same arrangement was seen in the morphologically comparable penil genital corpuscles of the same species. Based on the particular arrangement of blood vessels and nerve fibers in the genital corpuscles, some authors postulate the presence of a neuro-vascular glomerulus.