Beyond the Bowl: Understanding Amino Acid Requirements and Digestibility to Improve Protein Quality Metrics for Dog and Cat Foods.

The determination of amino acid (AA) requirements for mammals has traditionally been done through nitrogen (N) balance studies, but this technique underestimates AA requirements in adult animals. There has been a shift toward researchers using the indicator amino acid oxidation (IAAO) technique for the determination of AA requirements in humans, and recently in dogs. However, the determination of AA requirements specific to adult dogs and cats at maintenance is lacking and the current requirements outlined by the National Research Council are based on a dearth of data and are likely underreporting the requirements of indispensable AA (IAA) for the population. To ensure the physiological requirements of our cats and dogs are met, we need methods to accurately and precisely measure digestibility. In vivo methods, such as ileal cannulation, are most commonly used, however, due to ethical considerations, we are moving away from animal models and toward in vitro methods. Harmonized static digestion models have the potential to replace in vivo methods but work needs to be done to have these methods more accurately represent the gastrointestinal tract (GIT) of cats and dogs. The Digestible IAA Score (DIAAS) is one metric that can help define protein quality for individual ingredients or mixed diets that uses AA SID estimates and ideally those can be replaced with in vitro AA digestibility estimates. Finally, we need accurate and reliable laboratory AA analyses to measure the AA present in complete diets, especially those used to quantify methionine (Met) and cysteine (Cys), both often limiting AAs in cat and dog diets. Together, this will guide accurate feed formulation for our companion animals to satisfy requirements while avoiding over-supplying protein, which inevitably contributes to excess N excretion, affecting both the environment and feed sustainability.

The Pulse of It: Dietary Inclusion of Up to 45% Whole Pulse Ingredients with Chicken Meal and Pea Starch in a Complete and Balanced Diet Does Not Affect Cardiac Function, Fasted Sulfur Amino Acid Status, or Other Gross Measures of Health in Adult Dogs.

BACKGROUND: Pulses are an attractive alternative protein source for all mammals; however, recent reports suggest that these ingredients may be related to developing dilated cardiomyopathy in dogs. OBJECTIVES: The primary objective of this study was to quantify the effects of dietary pulse intake by adult dogs on cardiac function using echocardiographic measurements and cardiac biomarkers N-terminal pro-B-type natriuretic peptide and cardiac troponin I (cTnI). Second, to investigate the effects of pulse consumption on plasma sulfur amino acid (SAA) concentrations as pulses are generally low in SAA and may limit taurine synthesis. Last, to assess the general safety and efficacy of feeding pulse-containing diets on canine body composition and hematological and biochemical indices. METHODS: Twenty-eight privately-owned domestic Siberian Huskies (13 females; 4 intact, and 15 males; 6 intact) with a mean age of 5.3 ± 2.8 y (± SD) were randomly assigned to 1 of 4 dietary treatments (n = 7/treatment), with equal micronutrient supplementation and increasing whole pulse ingredient inclusion (0%, 15%, 30%, and 45%) with pea starch used to balance protein and energy. RESULTS: After 20 wks of feeding, there were no differences (P > 0.05) in echocardiographic parameters, N-terminal pro-B-type natriuretic peptide, and cTnI concentrations among treatments or across time within treatment (P > 0.05), indicating no differences in cardiac function among treatments. Concentrations of cTnI remained below the safe upper limit of 0.2 ng/mL for all dogs. Plasma SAA status, body composition, and hematological and biochemical indices were similar among treatments and over time (P > 0.05). CONCLUSIONS: The results from this study suggest that increasing the inclusion of pulses up to 45% with the removal of grains and equal micronutrient supplementation does not impact cardiac function concurrent with dilated cardiomyopathy, body composition, or SAA status and is safe for healthy adult dogs to consume when fed for 20 wks.

A Case of Thrombotic Thrombocytopenic Purpura Possibly Induced by Graves' Disease.

Thrombotic thrombocytopenic purpura (TTP) has historically been diagnosed with a pentad of features, i.e., thrombocytopenia, micro-angiopathic hemolytic anemia (MAHA), fever, neurological abnormalities, and kidney failure. Traditionally, TTP cases have been described in healthy adults. However, their association with autoimmune diseases is now well documented in the literature. There is limited availability of literature on the association between TTP and Graves' disease (GD). Here, we report a case of an adult female, a known case of Graves' disease, who has now been diagnosed with an acquired case of TTP. The presence of MAHA associated with thrombocytopenia was considered a clinical diagnosis of TTP and the patient immediately underwent plasma exchange (PEX), which led to the resolution of complaints. Hyperthyroidism cases should be adequately followed up as clinical severity could lead to the emergence of TTP.

A proof of principle study investigating the effects of supplemental concentrated brewer's yeast on markers of gut permeability, inflammation, and fecal metabolites in healthy non-challenged adult sled dogs.

Yeast-derived ß-glucans impact immunity, though their effects on gut permeability and inflammation are less understood. Most research has investigated other components of the yeast cell wall, such as the prebiotic mannan- and fructo-oligosaccharides. The objective of this study was to assess the effects of feeding a concentrated yeast product on markers of inflammation (serum amyloid A [SAA] and haptoglobin [Hp]) and oxidative status (malondialdehyde [MDA]), fecal products of fermentation, and gut permeability. Nineteen privately owned domestic Siberian huskies, and one Alaskan husky (9 females: 5 intact, 4 spayed; 11 males: 3 intact, 8 neutered), with an average age of 4.8 ± 2.6 yr and body weight (BW) of 25.6 ± 4.1 kg, were used in this study. Dogs were blocked and randomly allocated to one of two diet groups. Ten dogs received a dry extruded diet. The other 10 received the same diet top dressed with yeast for a daily ß-glucan dose of 7 mg/kg BW for 10 wk. Fecal collection, for evaluation of fecal metabolites, and scoring occurred weekly. Gut permeability was assessed using the chromium-labeled ethylenediamine tetra-acetic acid (Cr-EDTA) and iohexol markers prior to the initiation of dietary treatment and after 10 wk of treatment. Blood samples were collected premarker administration and 0.5, 1, 2, 3, 4, 5, and 6 h postadministration. Fasting concentrations of SAA, Hp, and MDA were measured on weeks -1, 2, 4, and 8. Incremental area under the curve (I-AUC) was calculated for serum iohexol and Cr-EDTA concentrations. All data were analyzed using PROC GLIMMIX of SAS with dog as random effect, and week as fixed effect and repeated measure. Dogs receiving treatment tended to have decreased I-AUC of Iohexol (P = 0.10) and Cr-EDTA (P = 0.06) between baseline and cessation of treatment compared to the change over time in I-AUC for control (Ctl) dogs. Treatment dogs had lower Hp concentrations (P ≤ 0.05) than Ctl. There were no differences between treatments for SAA and MDA concentrations (P > 0.05). Fecal arabinose concentrations were greater in treatment (Trt) dogs (P ≤ 0.05) compared to Ctl, though no other fecal metabolites were affected by treatment. There was no difference in the relative frequency of defecations scored at any fecal score between Trt and Ctl dogs, and mean score did not differ between groups (P > 0.10). These data suggest that concentrated brewer's yeast may have the potential to reduce gut permeability without impacting inflammatory status and markers of health in adult dogs.

This study evaluated the effects of concentrated brewer's yeast on gut health in dogs. Nineteen Siberian Huskies and one Alaskan husky were blocked and randomly allocated to one of two groups. Treatment dogs received a yeast supplement for 10 wk, while control dogs received no supplement. Dogs were administered two markers to assess intestinal permeability prior to start of treatment and following 10 wk of treatment. Blood samples were collected and analyzed for markers of inflammatory status (serum amyloid A [SAA] and Haptoglobin [Hp]) and oxidative status (serum malondialdehyde [MDA]). Fecal samples were collected weekly to assess fecal score as well as fecal metabolite concentrations. Intestinal permeability was reduced in treatment dogs following treatment, and no change was observed in the control group. Treatment dogs had lower Hp concentrations than control (Ctl), but there were no differences between treatments for SAA and MDA. Fecal arabinose concentrations were significantly greater in the treatment group when compared to control. There were no differences in the relative frequency of defecations scored at any fecal score between treatment and Ctl dogs, nor did mean score differ between the groups. This study suggests that concentrated brewer's yeast may reduce gut permeability and inflammation without detrimentally impacting markers of health in adult dogs.

A new polymorph of ciprofloxacin saccharinate: Structural characterization and pharmaceutical profile.

In this study, a new polymorph of ciprofloxacin saccharinate has been thoroughly evaluated with respect to structural as well as biopharmaceutical properties. Preliminary characterization of the new polymorph was performed by differential scanning calorimetry and thermogravimetric analysis, later confirmed by Fourier transform infra-red spectroscopy. The crystal structure was determined from the powder X-ray diffraction pattern using the direct-space algorithm. It lies in the triclinic P-1 space group. It is having lattice parameters different from previously reported forms. The solid-state 13C NMR data calculated from the crystal structure by exploiting density functional theory were found to be in excellent agreement with corresponding experimental 13C NMR data, thus providing a robust validation of the authenticity of the structure. The prepared polymorph shows enhanced aqueous solubility and dissolution rate in contrast to previously reported polymorph. The new form demonstrated improved oral bioavailability and inhibition of bacterial species. The enhanced biopharmaceutical properties are attributed to the higher extent of its absorption and distribution with respect to the individual components. The new form is a potential candidate for the pharmaceutical industry.

New conformational polymorph of hydrochlorothiazide with improved solubility.

CONTEXT: To characterize a new conformation of hydrochlorothiazide (HCT) with better solubility and establishing its relationship with previously reported form I, obtained during attempted crystallization experiments. OBJECTIVE: The aim of present investigation is to unveil a new conformational polymorph (form IA) having a higher solubility compared to commercially available form I. MATERIALS AND METHODS: New form (IA) was obtained from slow evaporation as well as by solvent-antisolvent method and was then characterized by DSC, FTIR, PXRD and SCXRD. Equilibrium solubility profile shows that it is more soluble than form I. RESULTS: Appearance of phase transition endotherm at 215.87 °C in DSC spectra indicated the existence of new polymorph which was further confirmed by FTIR and PXRD. Single crystal study showed significant difference in various bond angles and torsion angles of the two forms. The solubility exhibited by form IA was (938 µg/mL) compared to form I (791 µg/mL) in water. DISCUSSION: Complete structural analysis and molecular arrangements in the unit cell along with the DSC and FTIR data confirm the existence of new conformer of HCT. CONCLUSION: This study reveals the existence of a new conformational polymorph of HCT molecule having higher solubility could prove to be promising in pre-formulation.