From fish‐processing waste to feed additives for crayfish

This research studied the in vitro compatibility of Cherax quadricarinatus digestive proteases and crude enzyme extracts recovered from fish‐processing waste to evaluate their potential use as feed additives to increase digestion efficiency in decapod crustaceans. The sources of exogenous enzymes were: Pleoticus muelleri (Pm), Artemesia longinaris (Al), and Illex argentinus (Ia). The midgut glands of early (7.2 ± 0.34 g) and advanced juveniles (13.8 ± 1.49 g) of C. quadricarinatus were used for all the assays. The compatibility and synergy between crayfish and exogenous enzymes were evaluated through sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) electrophoresis and the hydrolysis of azocasein and four different meals. SDS–PAGE gels demonstrated that crayfish bands remained active when their enzymes were combined with the enzymes from Pm and Ia. An apparent enzymatic synergism was found when Pm and crayfish proteases were incubated together at pH 6 and 8 with azocasein (p ? 0.05). The ability to hydrolyze the different feed ingredients varied among the enzyme combinations assayed. Our findings suggest that fish waste has potential as a source of proteases, adding value to these processing residues and promoting a zero‐waste industry. Enzymes obtained from Pm and Ia are suitable to be used as food additives for crayfish. The results should be validated through feeding trials.     

Oestrous Synchronization,Ovarian Superovulation and Intraspecific Transfers From a Closed Breeding Colony of Inbred SLA Miniature Pigs

The inbred SLA miniature pig is a unique animal model developed for organ transplantation studies and pre‐clinical experimental purposes. Reported oestrous synchronization and superovulation treatments were examined in two SLA haplotypes (AA and DD) to allow collection of embryos for both practical embryo transfer and experimental technologies from a closed breeding colony. Pre‐puberal miniature pigs were poor responders to oestrous synchronization treatments, while post‐puberal sows were equivalent to commercial sows. Following superovulation, the ovulation number (corpora .hemorrhagica) was higher (p < 0.05) in the cycling sows when compared with non‐cycling sows. Ovulations were equivalent to commercial pre‐puberal gilts and non‐cycling sows (p > 0.05). No difference in ovulation number between haplotypes was observed, which differs from the previous report (DD>AA). Collection of zygotes for pronuclear injection was the highest in the non‐cycling post‐puberal miniature pig group (p < 0.05), although significantly lower when compared with the commercial pig treatment groups (p < 0.05). The incidence of cystic endometrial hyperplasia in our colony was equivalent to rates observed in commercial pigs. Pronuclear visualization following centrifugation was the highest in the non‐cycling miniature sow group and approximates to about 25% of ovulations and about half the rate observed in the commercial pigs (50%). Miniature pig embryos transferred between SLA haplotypes and transfer of DD embryos to commercial pigs resulted in live births at a higher efficiency than previously reported. This study demonstrates the feasibility of undertaking assisted reproductive technologies in a closed breeding colony of inbred SLA miniature pigs without compromise to the breeding programmes.     

Assessment of a biofilm‐based culture system within zero water exchange on water quality and on survival and growth of the freshwater shrimp Neocaridina heteropoda heteropoda

The contribution of biofilm to water quality and as a food source for the culture of the freshwater shrimp Neocaridina heteropoda heteropoda was assessed in indoor aquaria using a zero water exchange system. Two successive phases were conducted to evaluate biofilm development on different substrates (polyethylene net: PN, plastic bottles: PET, agrovelo: AV) and the effect of biofilm to shrimps culture. The biofilm grown on all substrates helped to keep a good water quality by the uptake of nitrogen compounds and the production of high levels of dissolved oxygen associated to the proliferation of autotrophic microorganisms. High survival, reproduction and hatching of shrimps were achieved in all groups mainly associated with good water quality. Final biomass of the shrimps was significant higher for PN and AV groups; while specific growth rate and the levels of lipids of the shrimps yielded similar values for all treatments indicating that the three substrates allowed the growth of a biofilm that resulted in a healthy food source with similar nutritional value for shrimps. The results show that the production of N. heteropoda heteropoda could be successfully conducted by a biofilm‐based culture system with no water exchange, and thus contributing to a better water use. All materials tested were suitable substrates for biofilm growth, though AV and PET could reduce significantly production costs when compared to the PN. Moreover, by the recycling and reuse of waste materials (such as plastic bottles) could contribute to the development of a responsible, sustainable and environmentally friendly culture method.     

Feline acromegaly

Acromegaly, or hypersomatotropism, results from chronic, excessive secretion of growth hormone in the adult animal. The anabolic effects of growth hormone are exerted through the intermediary hormone, insulin-like growth factor 1, which is produced in the liver under the influence of growth hormone. Feline acromegaly is caused by a pituitary adenoma that secretes excessive amounts of growth hormone. Characteristic effects of excessive growth hormone secretion include the development of diabetes mellitus and growth of the acral segments of the body (jaw, extremities, skull, etc.). Acromegaly occurs in older, predominately male cats and is often associated with diabetes mellitus. Other clinical signs include stridor, enlargement of the jaw and extremities, lean weight gain, and organomegaly (heart, liver, kidney, etc.). Diagnosis is made by documentation of increased levels of growth hormone or insulin-like growth factor (or both) and demonstration of a pituitary mass via magnetic resonance imaging or computed tomography. The most effective treatment to date has been radiation therapy. Prognosis is fair to good with proper treatment.     

Pituitary deficiencies

Diabetes insipidus, arising from damage to or congenital abnormalities of the neurohypophysis, is the most common pituitary deficiency in animals. Hypopituitarism and isolated growth hormone or thyrotropin deficiency may result in growth abnormalities in puppies and kittens. In addition, treatment of associated hormone deficiencies, such as hypothyroidism and hypoadrenocorticism, in patients with panhypopituitarism is vital to restore adequate growth in dwarfed animals. Secondary hypoadrenocorticism is an uncommon clinical entity; however differentiation of primary versus secondary adrenal insufficiency is of utmost importance in determining optimal therapy. This article will focus on the pathogenesis, diagnosis and treatment of hormone deficiencies of the pituitary gland and neurohypophysis.     

Endocrine Causes of Calcium Disorders

Endocrine diseases that may cause hypercalcemia and hypocalcemia include hyperparathyroidism, hypoparathyroidism, thyroid disorders, hyperadrenocorticism, hypoadrenocorticism, and less commonly pheochromocytoma and multiple endocrine neoplasias. The differential diagnosis of hypercalcemia may include malignancy (lymphoma, anal sac carcinoma, and squamous cell carcinoma), hyperparathyroidism, vitamin D intoxication, chronic renal disease, hypoadrenocorticism, granulomatous disorders, osteolysis, or spurious causes. Hypocalcemia may be caused by puerperal tetany, pancreatitis, intestinal malabsorption, ethlyene glycol intoxication, acute renal failure, hypopararthyroidism, hypovitaminosis D, hypomagnesemia, and low albumin. This article focuses on the endocrine causes of calcium imbalance and provides diagnostic and therapeutic guidelines for identifying the cause of hypercalcemia and hypocalcemia in veterinary patients.     

Urinary gamma-glutamyl transpeptidase activity in dogs with gentamicin-induced nephrotoxicity

Serum creatinine concentrations, 24-hour endogenous creatinine clearance, and 24-hour urinary gamma-glutamyl transpeptidase (UGGT) activity were measured daily in 6 dogs given nephrotoxic dosages of gentamicin (10 mg/kg of body weight) every 8 hours for 10 days. Mean UGGT activity was significantly increased by day 5 (P less than 0.05) and preceded significant increases in serum creatinine values (greater than 2.0 mg/dl) observed on day 9. Endogenous creatinine clearance remained within normal limits (2.98 +/- 0.96 ml/min/kg) until day 8. Urinalyses performed 8 days after initiation of gentamicin treatment indicated renal tubular damage (granular casts) in 1 of the 6 dogs, and glucosuria in 3 of the 6 dogs. Measurement of UGGT activity was a more sensitive and reliable method of assessing acute renal tubular damage induced by gentamicin than were serum creatinine concentrations or 24-hour endogenous creatinine clearance.     

The Effects of Cryopreservation on the Morphometric Dimensions of Iberian Red Deer (Cervus elaphus hispanicus) Epididymal Sperm Heads

Computer-automated sperm-head morphometry was used in this study to determine the effects of cryopreservation on red deer sperm-head morphometry. Epididymal sperm samples were collected from 40 mature stags and were divided. One portion was diluted at room temperature in a Tris-citrate egg yolk medium, containing 6% glycerol. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours. After thawing, sperm smears were prepared as described above. All slides were air dried and stained with Hemacolor. The sperm-head dimensions for length, width, area, perimeter and shape factor (length/width), for a minimum of 135 spermatozoa were determined for each slide by means of the Sperm-Class Analyser (SCA). Firstly, our results show that cryopreservation substantially reduced (p < 0.001) sperm motility and plasma membrane and acrosome integrities. In addition, sperm heads were significantly smaller in cryopreserved spermatozoa than in the companion extended samples for area (32.05 microm2 vs 32.56 microm2; p < 0.05), length (8.46 microm vs 8.53 microm; p < 0.0001) and shape factor (1.833 vs 1.849; p < 0.0001) for all stags. These differences were found within 29 of 40 stags (75%) for at least three of the morphometric parameters. The individual variability (CV) of sperm head measurements from extended samples was negatively correlated (p < 0.005) with the per cent of change in sperm head measurements after cryopreservation for area (r = -0.465), width (r = -0.483) and perimeter (r = -0.375). Thus, the lower the sperm head variability in the extended samples, the greater the sperm change as a consequence of the cryopreservation. These results suggest that the variability (heterogeneity) in sperm head dimensions of individual stags may be a good indicator of sperm freezability.