Effect of amino acid enriched diets on hemolymph amino acid composition in honey bees.

Amino acids (AAs) are an abundant class of nectar solutes, and they are involved in the nectar attractiveness to flower visitors. Among the various AAs, proline is the most abundant proteogenic AA, and γ-amino butyric acid (GABA) and ß-alanine are the two most abundant non-proteogenic AAs. These three AAs are known to affect insect physiology, being involved in flight metabolism and neurotransmission. The aim of this study was to investigate the effects of artificial diets enriched with either ß-alanine, GABA, or proline on consumption, survival, and hemolymph composition in honey bees belonging to two different ages and with different metabolism (i.e., newly emerged and foragers). Differences in feed intake among diets were not observed, while a diet enriched with ß-alanine improved the survival rate of newly emerged honey bees compared to the control group. Variations in the hemolymph AA concentrations occurred only in newly emerged honey bees, according to the diet and the time of hemolymph sampling. A greater susceptibility of young honey bees to enriched diets than older honey bees was observed. The variations in the concentrations of hemolymph AAs reflect either the accumulation of dietary AAs or the existence of metabolic pathways that may lead to the conversion of dietary AAs into different ones. This investigation could be an initial contribution to studying the complex dynamics that regulate hemolymph AA composition and its effect on honey bee physiology.

Effects of Virgin Coconut Oil-Enriched Diet on Immune and Antioxidant Enzymatic Activity, Fat and Vitellogenin Contents in Newly Emerged and Forager Bees (Apis mellifera L.) Reared in Cages.

Searching for artificial diets positively affecting the survival, immune and antioxidant systems of honey bees is one of main challenges occurring in beekeeping. Among nutrients, lipids play a significant role in insect nutrition as structural components in cell membranes, energy sources and reserves, and are involved in many physiological processes. In this context, the aim of this work was to investigate the effect of 0.5% and 1% coconut oil-enriched diet administration on newly emerged and forager bees survival rate, feed intake, immune system, antioxidant system and both fat and vitellogenin content. In newly emerged bees, supplementation with 1% coconut oil determined a decrease in feed consumption, an increase in survival rate from the 3rd to 14th day of feeding, a short-term decrease in phenoloxidase activity, an increase in body fat and no differences in vitellogenin content. Conversely, supplementation with 0.5% coconut oil determined an increase in survival rate from the 3rd to 15th day of feeding and an increase in fat content in the long term (i.e., 20 days). Regarding the forager bee diet, enrichment with 0.5% and 1% coconut oil only determined an increase in fat content. Therefore, supplementation with coconut oil in honey bee diets at low percentages (0.5 and 1%) determines fat gain. Further investigations to evaluate the use of such supplement foods to prevent the fat loss of weak families during winter are desirable.

Settlement of a stable wolf pack in a highly anthropic area of Pisan hills: Relationship with animal husbandry and hunting in a human-wolf coexistence perspective.

Anthropic areas play a pivot role for main wolf conservation challenges. Wolf presence in the higher Pisan hills has been well documented while wolf settlement in the lower Pisan hills is still uncertain. In this study, long-term information on wolf presence in a highly anthropic area of the lower Pisan hills was collected by using non-invasive monitoring techniques. Furthermore, both the relationship of this predator with human activity and the impact of hunting on wolf presence have been investigated. The results obtained indicate the presence of a stable and reproductive wolf pack composed by both Italian wolf and hybrids individuals in the municipalities of Crespina Lorenzana and Casciana Terme Lari. A high impact of wolf on livestock was recorded in this area since no prevention systems were adopted by farmers. Wolf appears not to have a negative impact on wild boar population. Similarly, wild boar drive hunting does not appear to affect the wolf pack presence in the area. Thereby wolf may play a key role as controller of wild population. Prevention strategies improvement becomes instrumental to promote wolf-human coexistence. Further investigation to monitor pack hybridization level and turnover and to assess the impact of packs on wild population and livestock in anthropic areas is desirable.

Impact of Different Storage Temperature on the Enzymatic Activity of Apis mellifera Royal Jelly.

Royal Jelly is a nutrient secretion of nurse bees and a high interest functional food in human nutrition. Very little information is available on its chemical composition integrity and enzymatic activity during shelf life and assessment of new freshness markers are desirable for its conservation. In this study, the activity of glucose oxidase, five proteases and two antioxidant enzymes in refrigerated and frozen Royal Jelly for different storage times was preliminary investigated. Refrigeration determined a significantly reduction in glucose oxidase and carboxypeptidase A-like activity in Royal Jelly after one year of storage while no differences were recorded in the activity of these enzymes in frozen samples. After one year of storage glucose oxidase and carboxypeptidase A-like activity resulted higher in frozen samples frozen than in refrigerate ones. Results obtained suggest that the activities of these enzymes may be good markers of Royal Jelly freshness within 1 year at refrigeration condition. Freezing could be a valid alternative storage method to ensure a higher preservation of glucose oxidase and carboxypeptidase A-like activities for at least 1 year. Further investigation to determine the timing of glucose oxidase inactivation/degradation under refrigerated conditions and the enzymatic activity trend under prolonged frozen conditions are desirable.

Preliminary investigation on enzymatic activity in saliva of Hystrix cristata L., 1758.

Mammal's saliva contains a variety of electrolytes and proteins. They carry out an important role in the digestion process, in the antibacterial and antiviral activity, in lubrication and maintenance of oral general health status. It may also contain several enzymes according to dietary habits and general wellness. Sialochemistry is a valid alternative to the haematochemical analysis for the evaluation of animal health and nutritional status. At present, very little knowledge is available on health status and pathology of crested porcupine (Hystrix cristata) and no data are yet available on salivary enzymes. Between 2018 and 2020, a preliminary investigation of enzymatic activity on saliva samples was carried out from captured porcupines. In crested porcupine saliva, enzymatic activity of trypsin, chymotrypsin, N-Aminopeptidase, amylase, lignin peroxidise, cellulase and chitinase were recorded. Superoxide dismutase, catalase, glutathione S-transferase and alkaline phosphatase activity was also detected. The superoxide dismutase activity resulted higher (3.13 SD 3.58 U/mg proteins) than those of catalase (130.80 SD 110.65 mU/mg proteins) and glutathione S-transferase (20.21 SD 16.62 mM/mg proteins). Alkaline phosphatase activity resulted lower (5.91 SD 6.12 mU/mg proteins) than acidic phosphatase (19.00 SD 16.16 U/mg proteins) with the highest values of saliva alkaline phosphatases recorded in young individuals. These preliminary data bring new knowledge on crested porcupine saliva enzymes and may provide a useful tool for further investigation on the adaptive response of crested porcupine to different environmental condition and diet. Additional investigation concerning a possible alternative use of saliva enzymes as indicator of health and nutritional status of this rodent are desirable.

Field Chemical Immobilization of Free-Ranging Crested Porcupines with Zoletil®: A Reviewed Dosage.

The tiletamine-zolazepam mixture is a widely used anesthetic for chemical immobilization of wild mammals due to its short induction time, good muscle relaxation, smooth recovery with low convulsions occurrence, and minimal effect on respiration. An injection dose of 7-8 mg/kg of tiletamine-zolazepam has been proven to be an effective and safe immobilizing mixture for crested porcupines under field conditions. However, the occurrence of long immobilization and recovery times, with high excitement and convulsion during awakening, were recorded. In order to reduce such side effects after recovery, the effectiveness of a lower dosage (4-6 mg/kg) of tiletamine-zolazepam (Zoletil®) was tested. The results obtained confirm that the use of tiletamine-zolazepam in crested porcupine immobilization provides a quick induction, wide safety margin, and predictable awakening under field conditions. A smaller injection dosage of 5 mg/kg has been proven to be sufficient to ensure a short induction time (average: 7.1 min), with good muscle relaxation and little excitement of the animals during awakening. The lower dosage of tiletamine-zolazepam, while providing a shorter recovery time (average: 53.6 min), proves to be adequate for standard handling procedures. Furthermore, the smaller amount of tiletamine-zolazepam also ensures safe immobilization for pregnant individuals and porcupettes.

Hematological and Serum Biochemistry Values in Free-Ranging Crested Porcupine.

The crested porcupine is a widespread naturalized Italian rodent of African origin; nevertheless, very little information on the population abundance and its health status is available. In this study, the hematological and serum chemistry profile of 10 free-ranging captured crested porcupines was established for the first time. The mean hematological values resulted: 5.7 SD 0.4 M/µL for red blood cells; 13.6 SD 0.8 g/dL for hemoglobin; 77.3 SD 5.7 fL for mean corpuscular volume and 30.1 SD 4.7 g/dL for mean corpuscular hemoglobin concentration; 14.4 SD 7.2 K/µL for white blood cells; and 557.0 SD 469.9 K/µL for platelets. The mean urea and creatinine values resulted with 19.8 SD 8.3 mg/dL and 1.6 SD 3.0 mg/dL, respectively. The mean value of total protein was 6.7 SD 1.0 g/dL, with values of albumin higher than globulins. The mean activity of creatine kinase, aspartate transaminase, gamma-glutamyl transpeptidase, and alkaline phosphatase was 927.3 SD 607.6 U/L, 199.2 SD 70.8 U/L, 16.9 SD 13.7 U/L, and 256 SD 75.8 U/L, respectively. Highest values of alkaline phosphatase were recorded in two porcupines presenting severe injuries with clear signs of infection. These preliminary results may be a helpful tool in order to assess porcupine health status.

Crested Porcupine (Hystrix cristata L.): A New Potential Host for Pathogenic Leptospira Among Semi-Fossorial Mammals.

Wildlife plays a pivot role in the epidemiology of leptospirosis and rodents have a reservoir function for several Leptospira serogroups. The crested porcupine is the largest rodent of the Italian fauna and shares the same environment with red foxes, badgers, coypus and wild boars that are known to be infected by Leptospira. Between 2018 and 2019 the seroprevalence of Leptospira in crested porcupine was investigated for the first time. Overall 7 out of 14 sera (50 %) were found positive to Leptospira. Icterohaemorrhagiae resulted as the most detected serogroup (57 %) followed by Pomona, Australis and Sejroe. The highest titer (1:1600) was detected for the serogroup Australis. These results indicate that porcupines could be infected by several serogroup of Leptospira and the role of reservoir or accidental host need to be addressed. Further investigations are necessary in order to clarify the leptospirosis - epidemiology - wildlife framework in light of its potential zoonotic source.

Plasma Tryptophan/Large Neutral Amino Acids Ratio in Domestic Dogs Is Affected by a Single Meal with High Carbohydrates Level.

Aim of this study was to evaluate the plasma ratio between l-tryptophan (TRP) and five large neutral amino acids (isoleucine + leucine + phenylalanine + tyrosine + valine) (5LNAAs) after a single meal with high carbohydrates level. Five female Labrador Retrievers were involved. Each dog was fed three different meals: M1 (a mix of puffed rice, minced meat and olive oil), M2 (puffed rice and olive oil) and M3 (commercial dry food usually consumed) once in the morning per day for 30 days. Blood was collected right before the first meal (t0) and after 2, 4, 6, 8, 10 and 24 h. Plasma amino acids’ concentrations were measured using an HPLC (High-performance liquid chromatography) method with fluorimetric detection. Plasmatic TRP concentrations showed no significant difference between M1, M2 and M3 samples at any sampling time. M2 led to a decrease in 5LNAAs levels and consequently led to a significant higher TRP/5LNAAs ratios in the 6 h period after the provision of carbohydrates, compared to both M1 and M3. In addition, the mean TRP/5LNAAs ratio was significantly higher in M2 than in M3 at t8 and t10. These results indicate that meal composition affects TRP/5LNAAs ratio and possibly, TRP bioavailability.