The influence of crossbreeding on collagen solubility and tenderness of Infraspinatus and Semimembranosus muscles of semi‐intensively reared young bulls

The aim of the present study was to investigate the effects of crossbreeding on collagen content and solubility, shear force (WBSF) and the eating quality of Infraspinatus (INF) and Semimembranosus (SM) muscles of young bulls and the relationships between collagen content and solubility, shear force and the eating quality of beef. The experimental material comprised muscles of crossbred young bulls (about 600 days old) of Polish Holstein‐Friesian (PHF) × Limousine (LM) (n = 10), PHF × Charolaise (CH) (n = 9), PHF × Hereford (HER) (n = 9) breeds. The crossbreeding influenced WBSF, aroma and taste, total, water‐soluble, acid‐soluble, total soluble and insoluble collagen content, as well as the acid‐soluble, total soluble and insoluble collagen proportions. WBSF was significantly negatively correlated with sensorial tenderness and water‐soluble collagen content. The eating quality of beef obtained from different crossbreds was similar; however, the meat from PHF × LM and PHF × HER bulls had lower WBSF values than PHF × CH bulls. © 2016 Japanese Society of Animal Science     

Serum C-reactive protein concentration as an indicator of remission status in dogs with multicentric lymphoma

BACKGROUND: The acute-phase protein C-reactive protein (CRP) is used as a diagnostic and prognostic marker in humans with various neoplasias, including non-Hodgkin's lymphoma. OBJECTIVE: To evaluate if CRP could be used to detect different remission states in dogs with lymphoma. ANIMALS: Twenty-two dogs with untreated multicentric lymphoma. METHODS: Prospective observational study. Blood samples were collected at the time of diagnosis, before each chemotherapy session, and at follow-up visits, resulting in 287 serum samples. RESULTS: Before therapy, a statistically significant majority of the dogs (P = .0019) had CRP concentrations above the reference range (68%, 15/22). After achieving complete remission 90% (18/20) of the dogs had CRP concentrations within the reference range, and the difference in values before and after treatment was statistically significant (P < .001). CRP concentrations of dogs in complete remission (median, 1.91; range, 0.2-103) were significantly different (P = .031) from those of dogs with partial remission (median, 2.48; range, 0-89), stable disease (median, 1.77; range, 1.03-42.65), or progressive disease (median, 8.7; range, 0-82.5). There was profound variation of CRP measurements within each dog. CONCLUSIONS: CRP is useful in determining complete remission status after treatment with cytotoxic drugs. However, the individual variation between dogs means CRP concentration is not sufficiently different in other remission states to permit its use in monitoring progression of the disease. Greater reliability in determining remission status might be achieved by combining CRP concentration with other serum markers.     

Effect of Addition of Different Acetic Acid Concentrations on the Quality of Marinated Herring

This study investigated the effect of acetic acid concentrations from 3 to 8% on the physicochemical and sensory quality of marinated Atlantic and Baltic herring from fresh and frozen-thawed material. The increased concentration of acetic acid was found to exert a strong impact on decreased sensory scores, weight yield, and pH value as well as on an increased brightness parameter of meat. In turn, moisture, protein hydrolysis products (PHB), total volatile bases (TVB) content, and hardness parameter were affected by the higher addition of acid to a lesser extent. Enhanced protein hydrolysis was observed only at acetic acid concentration of 5% or 5–8%, whereas there was a decrease in the content of TVB only at an acid concentration of up to 4–5%. The marinated frozen-thawed fillets, compared to the fresh ones, required a greater addition of acid in the brine, by 1.5%, to reach a similar pH value. The freezing of fish contributed also to a decrease of PHB and free hydroxyproline, along with an increased concentration of acetic acid. The marinades from frozen-thawed herring contained more TVB, had worse color, and hardness parameters, as well as less yield.     

Effect of dietary <Emphasis Type="SmallCaps">l</Emphasis>-tryptophan on cannibalism,survival and growth in pikeperch <Emphasis Type="Italic">Sander lucioperca</Emphasis> (L.) post-larvae

The effect of supplemented commercial diets with crystalline l-tryptophan (TRP—5, 10 and 20 g TRP kg^?1) on cannibalism, survival and growth parameters of pikeperch post-larvae (Sander lucioperca) was evaluated. Fifteen-day-old pikeperch larvae (mean weight—6.8 mg) were reared during the next 28 days (20.5 °C, 16L:8D) in glass aquaria in a recirculating aquaculture system. The enzyme-linked immunosorbent assay showed that TRP-supplemented diets were effective in increasing the levels of serotonin (5-HT) in the body tissue of pikeperch. TRP supplementation resulted in a slight decrease in both types of cannibalism, although the reduction in cannibalism impact did not amount to more than a few percent. TRP treatment had no significant influence on the final survival of pikeperch post-larvae (ranged from 20.1 ± 12.4 to 29.0 ± 12.9 %). However, contrary to the earlier studies conducted on other fish species, no significant difference in the growth rates and feeding behavior of pikeperch between TRP-fed and control group were found. The final body weight and growth rate ranged from 0.211 ± 0.014 to 0.243 ± 0.016 and from 12.19 ± 0.38 to 12.76 ± 0.35 % day^?1, respectively. To our knowledge, this is the first study reporting the effects of TRP supplementation on the cannibalism–survival–growth relations in fish in the post-larval stage.     

The application of tannic acid to the elimination of egg stickiness at varied moments of the egg swelling process in pikeperch,Sander lucioperca (L.)

The aim of this article was to analyse the process of pikeperch, Sander lucioperca, egg swelling and to apply tannic acid to eliminate egg stickiness at different moments of the swelling process on artificially obtained eggs. The first experiment involved observation of egg swelling process and the second determined the effect of temperature (12, 14 and 16°C) on the egg swelling rate. The third experiment involved elimination of egg stickiness in a tannin solution (0.75 g L^?1) where eggs were submerged in a solution for 0.5, 1, 2 and 5 min – 5, 10, 15, 20, 25 and 30 min following gamete activation. The results indicate that the pikeperch egg swelling process lasts 30 min. It was found that the temperature did not affect the process duration. The results of the third experiment showed that the effectiveness of tannic acid application in egg stickiness elimination increases with time. The best result was obtained in groups of eggs submerged for 1 and 2 min (86.5% and 80.5% of larvae were obtained respectively) 30 min following the gamete activation. The results presented in this study for the first time indicate the possibility of highly effective procedure of egg stickiness elimination with tannic acid in pikeperch aquaculture.     

Immunostimulatory effects of dietary poly‐β‐hydroxybutyrate in European sea bass postlarvae

The stable production of high‐quality fry in marine aquaculture is still hampered by unpredictable mortality caused by infectious diseases during larval rearing. Consequently, the development of new biocontrol agents is crucial for a viable aquaculture industry. The bacterial energy storage compound poly‐β‐hydroxybutyrate (PHB) has been shown to exhibit beneficial properties on aquatic organisms such as enhanced survival, growth, disease resistance and a controlling effect on the gastrointestinal microbiota. However, the effect of PHB on the developing immune system of fish larvae has so far not been investigated. In this study, the effect of feeding PHB‐enriched Artemia nauplii on survival, growth and immune response in European sea bass (Dicentrarchus labrax) postlarvae was examined. Amorphous PHB was administered to 28‐day‐old sea bass postlarvae over a period of 10 days. The survival and growth performance were monitored, and the expression of 29 genes involved in immunity, growth, metabolism and stress‐response was measured. While the expression of the insulin‐like growth factor 1 (igf1), an indicator of relative growth, was upregulated in response to feeding PHB, the larval survival and growth performance remained unaffected. After 10 days of PHB treatment, the expression of the antimicrobial peptides dicentracin (dic) and hepcidin (hep) as well as mhc class IIa and mhc class IIb was elevated in the PHB fed postlarvae. This indicates that PHB is capable of stimulating the immune system of fish early life stages, which may be the cause of the increased resistance to diseases and robustness observed in previous studies.     

Historical spatial baselines in conservation and management of marine resources

Increased knowledge on the spatial distribution of marine resources is crucial for the implementation of a true ecosystem approach to management and the conservation of marine organisms. For exploited fish species characterized by aggregation behaviour during spawning time, the identification and tracking of spawning areas is essential for a correct assessment of their productivity and population abundance. To elucidate this concept, we reconstructed the spatio‐temporal distribution of adult plaice (Pleuronectes platessa, Pleuronectidae) during spawning time along the 20^th century. Historical data reveal that not only the abundance but also the former population richness was much higher than previously estimated and has declined because of protracted over‐exploitation during the last 30 years. We conclude that forecast of stock recovery to former levels of abundance neglecting spatial reorganizations might be over‐optimistic and shaded by a lost memory of the past population richness. These results reinforce the importance of managing exploited marine resources at a greater spatial resolution than has been carried out in the history of fishery management.