Generalized calcinosis cutis associated with disseminated paecilomycosis in a dog

A 4‐year‐old spayed female mixed breed dog was referred to the Michigan State University, Veterinary Teaching Hospital (MSU‐VTH) with vomiting, lethargy and anorexia of 2 weeks duration. Abdominal radiographs and ultrasonography showed hepatosplenomegaly. Cytological evaluation of ultrasound‐guided fine needle aspirates of the liver and spleen revealed fungal organisms and pyogranulomatous inflammation; fungal culture documented Paecilomyces variotii infection. The dog received antifungal therapy and supportive care. Multiple firm plaque‐like skin lesions, predominantly involving the inguinal region, developed 18 days after initial presentation and were diagnosed histopathologically as calcinosis cutis. While generalized calcinosis cutis has been reported in three dogs with blastomycosis and one dog with leptospirosis, the association with disseminated Paecilomyces spp. infection is novel.     

Performance,serum amino acid concentrations and expression of selected genes in pair‐fed growing pigs exposed to high ambient temperatures

Heat stress (HS) depresses pig performance mainly because of appetite reduction, although other factors involved in the cellular availability of nutrients may also contribute to that depression. An experiment was conducted with twelve pair‐fed pigs (30.3 ± 2.7 kg BW) to examine the effect of severe HS (up to 45 °C) on the expression of genes coding for two cationic amino acid (AA) transporters (b^0,+AT and CAT‐1), leptin, heat‐shock protein (Hsp‐90) and myosin in several tissues; serum concentrations (SC) of AA; and performance. There were two treatments: Comfort, pigs housed at an average temperature of 22 (±2) °C; and HS, pigs housed in a similar room with no climate control, where temperature was raised up to 45 °C. All pigs received the same wheat–soybean meal diet and had similar daily feed intake. Comfort pigs had a higher daily gain and better gain/feed ratio than HS pigs (p < 0.05). The expression of b^0,+AT in jejunum and liver, that of myosin in the Semitendinosus muscle, and leptin in adipose tissue was lower, but CAT‐1 in jejunum and liver, and Hsp‐90 in liver was higher in HS pigs. The SC of Lys and Met in HS pigs were around 55% and 20%, respectively, of that in Comfort pigs (p < 0.05). In conclusion, HS affects the expression of cationic AA transporters, myosin, Hsp‐90, leptin; the SC of Lys and Met; and the performance of pair‐fed pigs. These results suggest that HS‐related changes in gene expression affect the performance of pigs beyond the effect caused by the reduction in voluntary feed intake.     

A case of superficial suppurative necrolytic dermatitis of miniature schnauzers with identification of a causative agent using patch testing

A 9‐year‐old, castrated male, miniature schnauzer presented with malaise, anorexia, fever and severe inflammatory skin lesions on the dorsum, thighs and pinnae. The lesions developed 2 days after bathing with a commercial shampoo. Histopathological examination of skin samples revealed neutrophilic exocytosis, parakeratosis, epidermal hyperplasia and neutrophilic infiltration in the superficial dermis. Skin lesions resolved completely after 14 days of treatment with prednisolone and ofloxacin. Patch testing performed on the patient and a clinically healthy dog showed erythema at the site exposed to the culprit shampoo 48 h later only on the patient. Histopathological findings of the erythematous reaction were similar to those of the spontaneous skin lesions. Based on these findings, the dog was diagnosed with superficial suppurative necrolytic dermatitis of miniature schnauzers. The patch test results suggested that contact dermatitis to a commercial shampoo played a role in the pathogenesis of this disease.     

Cutaneous T‐cell lymphoma – Sézary syndrome in a Boxer

A 7‐year‐old male Boxer with a 3.5‐year history of atopy and food hypersensitivity was presented with multiple poorly circumscribed nodules and maculae of the skin and tongue, and jaundiced mucosal membranes. Cytologic and histopathologic examination of the skin lesions revealed cutaneous epitheliotropic lymphoma. Cells were CD3⁺ and CD8⁺ in flow cytometry. The CBC showed a moderate leukocytosis with 16% atypical lymphocytes with irregularly cleaved nuclei. Flow cytometric phenotyping of peripheral blood showed an elevated proportion of the CD8⁺ T‐lymphocyte subpopulation, indicating a malignant population of T‐cell origin, and the electropherogram of the PCR antigen receptor rearrangement produced a monoclonal peak for TCRγ. Liver enzyme activities were markedly increased and abdominal ultrasound examination showed increased echogenicity of the liver and enlarged abdominal lymph nodes. Fine‐needle aspirates of the liver confirmed infiltration with lymphocytes exhibiting the same morphology as the cells detected in skin and peripheral blood. Treatment was induced with L‐asparaginase, lomustine, and prednisone. Partial clinical remission of the skin and tongue lesions was achieved within 10 days, and hematologic abnormalities resolved. Despite further treatment with L‐asparaginase and lomustine, the dog relapsed within one month and was euthanized. Presence of malignant lymphocytes in skin, peripheral blood, and liver indicate a rare variant of leukemic cutaneous T‐cell lymphoma, equivalent of Sézary syndrome in a dog. This case report describes the use of flow cytometry as a complementary tool for lymphocyte characterization of skin lesions for the first time.     

Hypoglycemia associated with disseminated metastatic tonsillar squamous cell carcinoma producing insulin‐like growth factor‐I in a Pomeranian dog

A 13‐year‐old spayed female Pomeranian dog was presented for persistent, severe hypoglycemia (37 mg/dL; reference interval [RI] 75‐128 mg/dL). Progressive nonregenerative anemia (hematocrit 23.3%‐15.9%; RI 37.0%‐55.0%) and severe thrombocytopenia (36 000/µL; RI 200‐500 000/µL) were also noted. The serum insulin concentration was low (0.24 ng/mL; RI 0.302‐1.277 ng/mL). Computed tomography revealed multiple splenic nodules (1‐6 mm in diameter) and several hepatic nodules (7.6, 12 mm in diameter). Ultrasound‐guided fine‐needle aspiration of the splenic and hepatic nodules revealed low numbers of epithelial cells with mild cellular atypia, suggestive of a metastatic epithelial tumor, but the primary site was unknown at that time. On careful oral examination under general anesthesia, an enlarged right tonsil was noted grossly, and histopathologic examination of the tonsil diagnosed squamous cell carcinoma. Bone marrow aspirates and biopsies of the splenic and hepatic nodules were performed; all samples were diagnosed as metastatic carcinoma on histopathologic examination. No nodules were present in the pancreas, despite careful palpation during exploratory laparotomy. On immunohistochemistry, the neoplastic cells were positive for cytokeratin AE1/3 and insulin‐like growth factor (IGF)‐I but were negative for chromogranin A, PGP9.5, insulin, and inconclusive for IGF‐II. This is the first report of a primary IGF‐I‐producing squamous cell carcinoma in the tonsil of a dog with metastases to bone marrow, liver, and spleen, resulting in hypoglycemia.     

Polymorphism in promoter region of growth hormone receptor is associated with potential production capacity of insulin‐like growth factor‐1 in pre‐pubertal Holstein heifers

Insulin‐like growth factor‐1 (IGF‐1) is one of the important factors for growth, milk production and reproductive functions and mainly released from the liver in response to growth hormone (GH) via GH receptor (GHR) in cattle. Recently, some single nucleotide polymorphisms (SNPs) were identified in the bovine GHR gene. Some GHR‐SNPs were shown to be related to plasma IGF‐1 concentration in cattle. Hence, the capacity to IGF‐1 production in the liver might be affected by GHR‐SNP and associated with performance in the future. This study examined whether GHR‐SNP is associated with IGF‐1 production in the liver of pre‐pubertal heifers. In 71 Holstein calves, blood samples for genomic DNA extraction were obtained immediately after birth. To genotype the GHR‐SNPs in the promoter region, polymerase chain reaction (PCR) products were digested with restriction enzyme NsiI (cutting sites: AA, AG and GG). All heifers at 4 months of age were intramuscularly injected with 0.4 mg oestradiol benzoate. Blood samples were obtained from the jugular vein just before (0 h) and 24 h after injection. The number of AA, AG and GG at the NsiI site was 0, 17 and 54 respectively. In AG and GG, plasma GH concentrations were higher pre‐injection than 24 h post‐injection (p < 0.01). Moreover, plasma GH concentrations in AG post‐injection were higher than in GG (p < 0.05). In contrast, the GG genotype exhibited higher plasma IGF‐1 concentrations in pre‐injection than post‐injection (p < 0.01), although oestradiol did not change IGF‐1 concentration in the AG genotype. We conclude that the GG polymorphism in the promoter region of GHR is associated with a higher potential capacity of IGF‐1 production in the liver of cattle.     

Definitive‐intent intensity‐modulated radiation therapy provides similar outcomes to those previously published for definitive‐intent three‐dimensional conformal radiation therapy in dogs with primary brain tumors: A multi‐institutional retrospective study

Radiotherapy with or without surgery is a common choice for brain tumors in dogs. Although numerous studies have evaluated use of three‐dimensional conformal radiotherapy, reports of definitive‐intent, IMRT for canine intracranial tumors are lacking. Intensity‐modulated radiation therapy has the benefit of decreasing dose to nearby organs at risk and may aid in reducing toxicity. However, increasing dose conformity with IMRT calls for accurate target delineation and daily patient positioning, in order to decrease the risk of a geographic miss. To determine survival outcome and toxicity, we performed a multi‐institutional retrospective observational study evaluating dogs with brain tumors treated with IMRT. Fifty‐two dogs treated with fractionated, definitive‐intent IMRT at four academic radiotherapy facilities were included. All dogs presented with neurologic signs and were diagnosed via MRI. Presumed radiological diagnoses included 37 meningiomas, 12 gliomas, and one peripheral nerve sheath tumor. One dog had two presumed meningiomas and one dog had either a glioma or meningioma. All dogs were treated in the macroscopic disease setting and were prescribed a total dose of 45‐50 Gy (2.25‐2.5 Gy per fraction in 18‐20 daily fractions). Median survival time for all patients, including seven cases treated with a second course of therapy was 18.1 months (95% confidence of interval 12.3‐26.6 months). As previously described for brain tumors, increasing severity of neurologic signs at diagnosis was associated with a worse outcome. Intensity‐modulated radiation therapy was well tolerated with few reported acute, acute delayed, or late side effects.     

Insulin‐independent actions of glucagon‐like peptide‐1 in wethers

Insulin‐independent actions of glucagon‐like peptide‐1 (GLP‐1) are not yet clear in ruminants. Four Suffolk mature wethers (60.0 ± 6.7 kg body weight (BW)) were intravenously infused with insulin (0.5 mU/kg BW/min; from 0 to 90 min) and GLP‐1 (0.5 μg/kg BW/min; from 60 to 150 min) with both hormones co‐administered from 60 to 90 min, in a repeated‐measure design under euglycemic clamp for 150 min, to investigate whether GLP‐1 has insulin‐independent actions. Jugular blood samples were taken at 15‐min intervals for plasma hormones and metabolites analysis. Compared to baseline concentrations (at 0 min), insulin infusion decreased (P < 0.05) plasma concentrations of glucagon, non‐esterified fatty acids (NEFA), lactate, nonessential amino acids (NEAA), branched‐chain amino acids (BCAA), total amino acids (TAA) and urea nitrogen (UN). Insulin plus GLP‐1 infusion induced a greater increase (P < 0.05) in plasma concentrations of insulin and triglyceride (TG), but decreased (P < 0.05) glucagon, total cholesterol (T‐Cho), NEAA and UN plasma concentrations. GLP‐1 infusion increased (P < 0.05) NEFA, β‐hydroxybutyrate and TG, but decreased (P < 0.05) glucagon, T‐Cho, NEAA, BCAA and UN plasma concentrations. In conclusion, GLP‐1 exerts extrapancreatic roles in ruminants not only insulin‐independent but probably, in contrast to non‐ruminants, antagonistic to insulin effects.     

FC‐42 Sarcoptic mange epidemic in a cat population

Worldwide, sarcoptic mange in cats is seldom reported, and then only in sporadic individual cases. We describe an epidemic in a household with a dog and 25 cats. From September 2002, the dog was repeatedly treated with ivermectin for sarcoptic mange. The diagnosis was confirmed by skin scrapings. Fifteen months later, cats from the same household were diagnosed with severe sarcoptic mange. Twenty‐one of the cats were euthanized and necropsies were performed. Skin samples were taken from all cats from different body sites for histology, and skin scrapings were examined for ectoparasites. Samples for bacterial and dermatophyte culture were taken from six cats. Smears for cytology were made from lesions on four cats with severe mange. Sera from 21 cats and the dog were analysed for specific antibodies to Sarcoptesscabiei. Molecular characterizations of six individual mites were done. Large numbers of S.scabiei were isolated from the infected skin of most of the cats. Two‐thirds of the cats showed skin lesions compatible with chronic sarcoptic mange. Macroscopically, internal organs exhibited no obvious pathology. Yeast organisms and coccoid bacteria were found in the smears; penicillinase‐negative Staphylococcus aureus was isolated from all samples and Malassezia pachydermatis was identified from four cats. Sarcoptes scabiei was seen histologically in all cats showing chronic skin lesions. No other ectoparasites were found. All analysed cats had specific antibodies against S. scabiei. Twenty‐one cats tested negatively for FeLV and FIV. The mites had DNA sequences identical to S. scabiei from naturally infected dogs and Swedish wildlife. Funding: Self‐funded.     

Nonregenerative immune‐mediated anemia associated with a diffuse large B‐cell lymphoma in a captive jaguar (Panthera onca)

An 18‐year‐old male castrated jaguar (Panthera onca) was presented with anorexia and continuous bleeding from the oral cavity after a history of fighting with the partner animal. Clinical evaluation revealed ulcerating lesions on the gingiva and hard palate and a hematoma on the tongue. Computed tomography of the head and endoscopic examination of the esophagus and stomach were unremarkable. Hematology and clinical chemistry revealed severe nonregenerative anemia, mild thrombocytopenia, and moderate azotemia. Several PCRs for feline hemotropic mycoplasmas (Mycoplasma haemofelis, M heamominutium, M turicensis), Babesia felis, and Bartonella spp., as well as an FeLV antigen test were negative. The cytologic examination of a bone marrow aspirate was consistent with ineffective erythropoiesis, most likely due to immune‐mediated destruction of the erythroid precursor cells. Prednisolone therapy was initiated (1.25 mg/kg/day), and the CBC returned to normal 16 days after the initiation of the therapy. Anemia relapsed after 4 months and severe splenomegaly was noted. A repeat bone marrow aspirate revealed active erythropoiesis in the presence of erythroid precursor phagocytosis suggesting an immune‐mediated process. Splenic fine‐needle aspiration and tissue biopsies were taken, and all findings including histology and immunohistochemistry were consistent with a diffuse large B‐cell lymphoma (DLBCL). Five days later, the clinical condition deteriorated and the jaguar died. Histopathology following necropsy showed infiltration with neoplastic lymphoblasts in the spleen, liver, and abdominal lymph nodes. This case report describes a nonregenerative immune‐mediated anemia associated with a DLBCL in a jaguar.     

Use of real‐time quantitative PCR to document successful treatment of Mycoplasma haemocanis infection with doxycycline in a dog

An 8‐year‐old Jack Russell Terrier was diagnosed with hemolytic anemia caused by hemoplasmosis 4 years following splenectomy. Quantitative real‐time PCR (qPCR) analysis was used initially to confirm infection with Mycoplasma haemocanis and subsequently to monitor and direct medical therapy. Doxycycline was administered beyond resolution of clinical signs until hemoplasma DNA could no longer be detected by qPCR. The dog remained clinically healthy and hemoplasma‐negative 8 months following cessation of therapy. Canine hemoplasmosis should remain as a differential diagnosis for hemolytic anemia in dogs, particularly those that are splenectomized or immunocompromised, even in geographic regions where prevalence of infection is low. Prolonged doxycycline administration has been shown by qPCR to lead to sustained absence of detectable infection and should be considered as a first line treatment for canine hemoplasmosis.     

Cutaneous Alternaria infectoria infection in a dog in association with therapeutic immunosuppression for the management of immune‐mediated haemolytic anaemia

A 4‐year‐old, ovariohysterectomized, English springer spaniel on immunosuppressive therapy was re‐examined for the review of its immune‐mediated haemolytic anaemia and the recent development of skin lesions. For the 3 months since hospital discharge, the dog had been receiving 1.3 mg/kg prednisolone and 2.6 mg/kg ciclosporin, both administered orally twice daily. Physical examination revealed hepatomegaly and multiple, purulent, crusting, erosive to ulcerative lesions over different body areas. Onychorrhexis had occurred on one digit and the underlying corium had blackened. There were two proliferative and one plaque‐like lesions in the mouth. Thick walled fungal hyphae were detected in impression smears from all skin lesions and staining with periodic acid–Schiff’s stain confirmed the presence of multiple fungal hyphae and spores in all biopsies examined. Fungal culture isolated a heavy, pure growth of an Alternaria sp. which was identified as A. infectoria by sequencing the internal transcribed spacer 1 region of the rRNA gene. The animal’s condition prevented detailed investigation of the oral lesions. Withdrawal of the ciclosporin and reduction of the prednisolone dosage resulted in spontaneous resolution of the skin lesions within 40 days. Further gradual decrements in the prednisolone dosage to zero were carried out without recurrence of the immune‐mediated haemolytic anaemia. After 12 months, there has been no recurrence of either the skin lesions or the anaemia. To the authors’ knowledge, this is the first reported case of A. infectoria infection in a dog.     

Pharmacokinetics of an extended‐release formulation of eprinomectin in healthy adult alpacas and its use in alpacas confirmed with mange

The study objective was to determine the pharmacokinetics and clinical effects of an extended‐release 5% eprinomectin formulation (Longrange^®) following subcutaneous (s.c.) injection in healthy (n = 6) and mange‐infected (n = 4) adult alpacas. High‐performance liquid chromatography was used to analyze plasma samples obtained at regular intervals for 161 days following a single 5 mg/kg injection s.c. in healthy alpacas, and for 5 days following each dose (3 treatments, 2 months apart) in mange‐affected animals. Skin scrapings and biopsies were performed pre‐ and post‐treatment at two comparable sites in alpacas with mange. Four alpacas served as healthy controls. Eprinomectin plasma concentrations showed a biphasic peak (C_MAX‐1: 5.72 ± 3.25 ng/mL; C_MAX‐2: 6.06 ± 2.47 ng/mL) in all animals at 3.88 ± 5.16 days and 77 ± 12.52 days, respectively. Eprinomectin plasma concentrations remained above 1.27 ± 0.96 ng/mL for up to 120 days. Hematocrit (35.8 vs. 31.3%, P < 0.003) and albumin (3.5 vs. 2.8 g/dL P < 0.006) reduced significantly over 6 months in multidose animals, while fecal egg counts did not differ between groups. Self‐limiting injection site reactions occurred in 9 of 10 animals. Pre‐ and post‐treatment skin biopsies showed reduced hyperkeratosis, but increased fibrosis, with 1 of 4 alpacas remaining positive on skin scraping for mange. In conclusion, alpacas require a higher eprinomectin dose (5.0 mg/kg s.c.) than cattle, to reach comparable plasma concentrations.     

Precursor‐targeted immune‐mediated anemia in a dog with a stage IV mast cell tumor and bone marrow infiltration

A 12‐year‐old spayed female Shiba Inu dog was referred to our hospital for a suspected mast cell tumor (MCT) of the bone marrow (BM). Laboratory abnormalities included severe nonregenerative anemia (packed cell volume or PCV: 12.5%; reference interval (RI): 37.3‐61.7%; reticulocytes: 35.1 × 10³/µL; RI: 10‐110 × 10³/µL), and a few mast cells were visualized in the blood smear examination. The BM was hypercellular with hematopoietic cells, a decreased myeloid:erythroid (M:E) ratio (0.77; RI, 0.9‐1.8), and no dysplastic hematopoietic cells. Mast cells accounted for 11.5% of the total nucleated BM cells. Neoplastic mast cells and histiocytes phagocytizing erythroid progenitor cells were occasionally noted. The dog was diagnosed with precursor‐targeted immune‐mediated anemia (PIMA) concurrent and a stage IV MCT infiltrating the BM. Multimodal treatment included toceranib, imatinib, vinblastine, lomustine (CCNU), prednisolone, cyclosporine, mycophenolate mofetil, and a blood transfusion. The dog died due to MCT progression lasting 139 days after the initial BM examination. To the best of our knowledge, this is the first report of a dog presenting with PIMA and a stage IV MCT infiltrating the BM.     

A case of apparent canine erysipeloid associated with Erysipelothrix rhusiopathiae bacteraemia

Background – Erysipelothrix rhusiopathiae is a Gram‐positive facultative anaerobe found worldwide and is most commonly associated with skin disease in swine, while anecdotal reports of cases in dogs have been associated with endocarditis. Hypothesis/Objectives – Clinicians should consider systemic infectious diseases as a potential cause of erythematous skin lesions. Animals – A 5‐year‐old female spayed Labrador retriever presented with lethargy, anorexia and erythematous skin lesions while receiving immunosuppressive therapy for immune‐mediated haemolytic anaemia. Four days prior to presentation, the dog had chewed on a raw turkey carcase. Methods – Complete blood count, serum chemistry profile, urinalysis and blood cultures. Results – Blood cultures yielded a pure growth of E. rhusiopathiae serotype 1b. Amoxicillin 22 mg/kg orally twice daily for 2 weeks and discontinuation of azathioprine resulted in remission of fever and skin lesions. Conclusions and clinical importance – This report is the first documentation, to the best of the authors’ knowledge, of Erysipelothrix infection, a known zoonosis, in an immunosuppressed dog, highlighting the need for infectious disease monitoring in patients receiving such therapy. This information may also help educate veterinarians to include Erysipelothrix infection as a differential diagnosis in dogs with fever and skin lesions, as well as the role of blood cultures in diagnosing this disease.     

Pharmacokinetic investigations of the marker active metabolites 4‐methylamino‐antipyrine and 4‐amino‐antipyrine after intramuscular injection of metamizole in healthy piglets

Metamizole (MT) is a pyrazolone nonsteroidal anti‐inflammatory drug labelled for humans and animals. The aim of this study was to assess the pharmacokinetics of its active metabolites 4‐methylamino‐antipyrine (MAA) and 4‐amino‐antipyrine (AA) in male piglets after a single intramuscular injection of MT. Eight healthy male piglets were administered MT (100 mg/kg) intramuscularly. Blood was sampled at scheduled time intervals, and drug plasma concentrations evaluated by a validated HPLC method. MAA and AA plasma concentrations were quantitatively detectable from 0.25 to 48 h and 0.50 to 72 h, respectively, in 6 of 8 and 7 of 8 animals. The average maximum concentrations of MAA and AA were of 47.59 and 4.94 mg/mL, respectively. The average half‐lives were 8.57 and 13.3 h for MAA and AA, respectively. This study showed that the amount of MAA and AA produced in piglets is different to that in the animal species previously investigated. Further studies are necessary to understand whether these differences in MAA and AA plasma concentrations between animal species necessitate diverse therapeutic drug dosing.     

Pharmacokinetic parameters for single‐ and multi‐dose regimens for subcutaneous administration of a high‐dose ceftiofur crystalline‐free acid to neonatal foals

The objective of this study was to determine the pharmacokinetics of single‐ and multi‐dose ceftiofur crystalline‐free acid (CCFA) administered subcutaneously at a dose of 13.2 mg/kg to 12 neonatal foals 1–3 days of age. Six foals received a single subcutaneous dose, while 6 additional foals received 4 doses of CCFA at 48‐h intervals. Blood samples were collected at pre‐determined times following drug administration, and plasma concentrations of ceftiofur free acid equivalents (CFAE) were measured using high‐performance liquid chromatography. Following single‐dose administration of CCFA, the mean ± standard deviation maximum observed plasma concentration was 3.1 ± 0.6 μg/mL and observed time to maximal plasma concentration was 14.0 ± 4.9 h. Following multi‐dose administration of CCFA, the mean ±standard deviation times above CFAE concentrations of ≥0.5 μg/mL and ≥2.0 μg/mL were 192.95 ± 15.86 h and 78.80 ± 15.31 h, respectively. The mean ± standard deviation area under the concentration vs time curve (AUC_0→∝) was 246.2 ± 30.7 h × μg/mL and 172.7 ± 27.14 h × μg/mL following single‐ and multi‐dose CCFA administrations, respectively. Subcutaneous administration of CCFA at 13.2 mg/kg in neonatal foals was clinically well‐ tolerated and resulted in plasma concentrations sufficient for the treatment of most bacterial pathogens associated with neonatal foal septicemia. Multi‐dose administration of four doses at dosing interval of 48 h between treatments maintains appropriate therapeutic concentrations in neonatal foals.     

Branched‐chain amino acid ratios in low‐protein diets regulate the free amino acid profile and the expression of hepatic fatty acid metabolism‐related genes in growing pigs

Liver metabolism is affected by nutrients. The aim of this study was to explore the effects of low‐protein diets (17% crude protein, CP) supplemented with branched‐chain amino acids (BCAAs), including leucine (Leu), isoleucine (Ile) and valine (Val), on hepatic amino acid profile and lipid metabolism in growing pigs. The ratio of Leu : Ile : Val in all groups was 1 : 0.51 : 0.63 (20% crude protein, CP), 1 : 1 : 1 (17% CP), 1 : 0.75 : 0.75 (17% CP), 1 : 0.51 : 0.63 (17% CP) and 1 : 0.25 : 0.25 (17% CP) respectively. Results revealed that compared to the positive control group (1 : 0.51 : 0.63, 20% CP), the low‐protein diets significantly augmented the concentrations of most essential amino acids and non‐essential amino acids (p < .05), with the greatest values observed in the 1 : 0.25 : 0.25 group. Moreover, relative to the control, the low‐protein diets with the Leu : Ile : Val ratio ranging from 1 : 0.75 : 0.75 to 1 : 0.25 : 0.25 markedly downregulated the mRNA abundance of acetyl‐CoA carboxylase (ACC), lipoprotein lipase (LPL) and fatty acid‐binding protein 4 (FABP‐4) (p < .05), and upregulated the mRNA expression of hormone‐sensitive lipase (HSL), peroxisome proliferator‐activated receptor‐g coactivator‐1α (PGC‐1α), uncoupling protein 3 (UCP3) and liver carnitine palmitoyltransferase 1 (L‐CPT‐1) (p < .05). Therefore, our data suggest that protein‐restricted diets supplemented with optimal BCAA ratio, that is, 1 : 0.75 : 0.75–1 : 0.25 : 0.25, induce a shift from fatty acid synthesis to fatty acid oxidation in the liver of growing pigs. These effects may be associated with increased mitochondrial biogenesis.     

Effects of a short‐term supranutritional selenium supplementation on redox balance,physiology and insulin‐related metabolism in heat‐stressed pigs

Heat stress (HS) disrupts redox balance and insulin‐related metabolism. Supplementation with supranutritional amounts of selenium (Se) may enhance glutathione peroxidase (GPX) activity and reduce oxidative stress, but may trigger insulin resistance. Therefore, the aim of this experiment was to investigate the effects of a short‐term high Se supplementation on physiology, oxidative stress and insulin‐related metabolism in heat‐stressed pigs. Twenty‐four gilts were fed either a control (0.20 ppm Se) or a high Se (1.0 ppm Se yeast, HiSe) diet for 2 weeks. Pigs were then housed in thermoneutral (20°C) or HS (35°C) conditions for 8 days. Blood samples were collected to study blood Se and oxidative stress markers. An oral glucose tolerance test (OGTT) was conducted on day 8 of thermal exposure. The HS conditions increased rectal temperature and respiration rate (both p < .001). The HiSe diet increased blood Se by 12% (p < .05) and ameliorated the increase in rectal temperature (p < .05). Heat stress increased oxidative stress as evidenced by a 48% increase in plasma advanced oxidized protein products (AOPPs; p < .05), which may be associated with the reductions in plasma biological antioxidant potential (BAP) and erythrocyte GPX activity (both p < .05). The HiSe diet did not alleviate the reduction in plasma BAP or increase in AOPPs observed during HS, although it tended to increase erythrocyte GPX activity by 13% (p = .068). Without affecting insulin, HS attenuated lipid mobilization, as evidenced by a lower fasting NEFA concentration (p < .05), which was not mitigated by the HiSe diet. The HiSe diet increased insulin AUC, suggesting it potentiated insulin resistance, although this only occurred under TN conditions (p = .066). In summary, HS induced oxidative stress and attenuated lipid mobilization in pigs. The short‐term supranutritional Se supplementation alleviated hyperthermia, but did not protect against oxidative stress in heat‐stressed pigs.     

Changes in tissue free amino acid pools in growing chickens fed thermally treated vetch diets

A three‐day assay was developed to evaluate the effect of autoclaving on protein quality of vetch as an alternative to classical growth methods. Male chickens (n = 10/diet) were given approximately isonitrogenous diets based on raw or autoclaved vetch for 3 days. Samples of plasma, muscle and liver were obtained for free amino acid analysis. Heating vetch depressed growth (11.9 vs. 23.2 g/d; p < 0.05). Plasma methionine and histidine increased (0.05 < p < 0.06), while gluconeogenic amino acids tended to decrease (p < 0.10) after heating. Muscle free amino acids did not change except for a trend to increased methionine (p = 0.06) in birds fed autoclaved vetch. In liver, most essential amino acids, glycine, proline and tyrosine increased markedly with heated vetch diet. Correlations between plasma and muscle free amino acids were poor compared with those between plasma and liver free amino acids. Liver free amino acid pool was more sensitive than muscle or plasma pool to amino acid inflow modifications after vetch heating.