Melanocortin-4 receptor and proopiomelanocortin: Candidate genes for obesity in domestic shorthair cats

Obesity is an escalating global health problem affecting both humans and companion animals. In cats it is associated with increased mortality and multiple diseases, including diabetes mellitus. Two genes coding for proteins known to play a critical role in energy homeostasis across species are the proopiomelanocortin (POMC) gene and the melanocortin-4 receptor (MC4R) gene. A missense variant in the coding sequence of the feline MC4R (MC4R:c.92C>T) has been reported to be associated with diabetes and overweight in domestic shorthair cats, and while variants in the POMC gene are known to cause obesity in humans and dogs, variants in POMC and their association with feline obesity and diabetes mellitus have not been investigated to date. The current study aimed to assess the association between the previously described MC4R variant and body condition score (BCS), as well as body fat content (%BF) in 89 non-diabetic domestic shorthair cats. Furthermore, we investigated the feline POMC gene as a potential candidate gene for obesity. Our results indicate that the MC4R:c.92C>T polymorphism is not associated with BCS or %BF in non-diabetic domestic shorthair cats. The mutation analysis of all POMC exons identified two missense variants, with a variant in exon 1 (c.28G>C; p.G10R) predicted to be damaging. The variant was subsequently assessed in all 89 cats, and cats heterozygous for the variant had a significantly increased body condition score (p = 0.03) compared with cats homozygous for the wild-type allele. Results from our study provide additional evidence that the previously described variant in MC4R is not associated with obesity in domestic shorthair cats. More importantly, we have identified a novel variant in the POMC gene, which might play a role in increased body condition score and body fat content in domestic shorthair cats.

[Investigation of metabolic parame- ters in high yielding dairy cows in pasture based production systems]

In the present study differences in metabolism between New Zealand Holstein-Friesian (NZHF) and Brown Swiss (CH-BV) or Swiss Holstein-Friesian (CH-HF) were investigated in a grassland based milk production system in Switzerland. Therefore 14 pairs of CH-BV/NZHF and 11 pairs of CH-HF/NZHF were available. The parameters glucose, insulin, non-esterified fatty acids (NEFA), β-hydroxybutyrate (β-HB), urea and cholesterol were analysed at the times 5-3 weeks before the calculated partus and 2, 3, 5, 7, 10 and 18-22 weeks post partum. Only β-HB showed significantly higher concentrations (P = 0.0059) for both Swiss breeds compared to the NZ-HF. Regarding all other physiological parameters during early lactation New Zealand Holstein-Friesians were not different from Swiss breeds.

Feeding practice and influence on selected blood parameters in show jumping horses competing in Switzerland

The aim of this study was to compare the nutritional management of show jumping horses in practice with recommendations from the literature. Additionally, the effects of these feeding practices on several blood metabolic parameters before and after exercise were studied. Blood samples were collected in the field from 27 different horses at 71 trials on the level M1 to S2 show jumping competitions in Switzerland and questionnaires on feeding practice of the studied horses were evaluated. The questionnaires revealed that during training and on tournament days horses received on average 3.1 kg of concentrate per day (min. 2.0 kg, max. 6.6 kg) divided into two to three meals. The horses were fed on average 6.9 kg of roughage per day (min. 4.0 kg, max. 13.0 kg). Additionally, it was observed that the horses received the last meal on average 6 h 10 min (min. 1 h 50 min, max. 12 h 30 min) before the start of the first show jumping turn, respectively, 7 h 30 min (min 1 h 50 min, max. 13 h 0 min) before the second turn. Seven horses (35%) had access to hay waiting in the trailer between two turns. The statistical analysis revealed no significant influence of the concentrate feeding time point on lactate, triglyceride and insulin levels, but a significant influence on free fatty acids (FFA) and blood glucose concentrations. Roughage feeding of the show jumping horses 2-4 h prior to exercise revealed the most remarkable changes in blood parameters during the show jumping course. These results received under field conditions should be approved in future under standardized conditions.

Estimating energy losses with urine in the cat

Urinary energy losses in cats have to be determined in energy balance trials as well as for the calculation of the metabolizable energy (ME) content of cat food. The aim of the present study was: first, to assess whether the energy content of cat urine quantified by bomb calorimetry differs from that quantified using GE (kJ) urine = 33 kJ × g C urine + 9 kJ × g N urine and investigate whether this difference could be attributed to influences of diets. Second, to assess whether the subtraction of 3.1 kJ/g of protein intake used for estimation of metabolizable energy content of cat foods is confirmed as usable. Data from 27 energy and protein balance trials from different studies with complete sampling of urine and faeces (29 cats in part A and 35 cats in part B) were used. Gross energy, carbon and nitrogen were determined in food, faeces and urine. Gross energy values in urine tended to be higher when determined with the formula of Hoffman and Klein compared to bomb calorimetry. The average relative difference of gross energy values between the methods was 18.8%. The mean energy loss in kJ/g of protein intake resulted in 3.7 kJ/g protein intake, which was not statistically significantly different (p = 0.12) from the tested value of 3.1 kJ/g of protein intake. In conclusion, the formula of Hoffman and Klein is not appropriate for the estimation of energy in cat urine. In balance studies, it is advisable to quantify the urinary energy content by bomb calorimetry. In the second part of the study, the protein correction factor to determine ME of 3.1 kJ/g protein intake for urinary energy losses of Kienzle et al. could be confirmed.

Nährstoffgehalte und Eignung des Grundfutters zur Pferdefütterung: Eine Erhebung unter schweizerischen Bedingungen

For horses no special tables related to nutrients for Swiss roughage exist. For this reason samples of hay, straw, silage/haylage and green forage were taken from 46 horse keeping farms in 22 cantons. The samples were judged by sense and following the nutrient--and macromineral--content as well as the content of fructans were analysed. Regarding its quality no sample was totally inadequate for horses. The mean contents of crude protein in Swiss hay for horses were clearly lower than in hay for ruminants and in German hay for horses. The mineral contents (calcium, magnesium, phosphorus) showed a wide range. On average they were also lower than the values provided in tables for ruminants. Except for one sample the silages/haylages showed a dry matter content of more than 40 %. No nutrient tables for silage or haylage, which are such high in dry matter contents, were found in the literature. The contents offructans in silage/haylage and green forage also showed a wide range with a maximum of 94 g/kg DM fructan.

A survey on the feeding of eventing horses during competition

This study aims at the comparison of the actual feeding of horses with the recommendations from the literature, and it studies the effects of feeding and exercise on several blood metabolic parameters before and after exercise. Blood samples were collected from 25 horses during one-star eventing competitions and evaluated for blood glucose, insulin, lactate, free fatty acids and triglyceride levels. Questionnaires on the feeding practices of the horses were evaluated. The questionnaires revealed that during training, and on tournament days, horses received on average 4.3 kg of concentrate per day (min. 1.54 kg, max. 8 kg). The statistical analysis showed no significant effect of the amount of concentrate fed before exercise on the measured blood values. Oil was supplied as a supplementary energy source to 30% of the horses, but most of them only received very small quantities (0.02-0.4 l/day). Five horses (20%) had no access to salt supplements at all, and eleven horses (45%) had no access to salt on tournament days. Fifteen horses (60%) were supplied with mineral feed. Twenty-one horses (84%) had daily access to pasture during the training period. During competition, 55% of the horses received roughage ad libitum, compared with 37% during training. The majority of the horses received less roughage on days before the cross-country competition. It could not be ascertained whether feeding a large amounts of roughage had a beneficial effect on performance, because only a few horses in this study were fed with very restrictive roughage. Feeding of most of the horses was in agreement with the recommendations from the literature, except the need for sodium and chloride. The sodium and chloride need for sport horses may be overestimated in literature and needs to be re-evaluated.

Fermentation of six different forages in the semi-continuous fermentation technique Caesitec

The aim of the present study was to compare carbohydrate degradation of forages which store carbohydrates either predominantly as fructan or starch, in horses' hindgut. The effects of an abrupt change from hay-based feeding to green fodder-based feeding on the caecal flora were tested with the in vitro hindgut simulation technique 'Caesitec'. Six trials with different forages (English ryegrass, tall fescue, grass mixture-horses, grass mixture-cows, lucerne, white clover) were conducted. During a 4-day stabilisation period, samples were taken once a day before loading the fermenters with hay. After diet-change to forage-based feeding, samples were taken four times a day. Ammonia and pH-value were measured before and 1, 2 and 6 h after loading the 'Caesitec'. Gas formation was measured daily. Bacterial numbers, lactate and short chain fatty acids were detected at four time-points of each trial. The grass mixtures contained the highest amounts of fructan. The pH-values were in the physiological range from pH 6 up to 7 (6.58-6.83) by feeding all forages. Gas formation, anaerobic and aerobic bacterial numbers increased after diet change from hay to any forage. The maximum amount of fructan (3.75 g/kg) in swiss pasture did not cause a permanent pathological change in the hindgut-flora.

Cats during gestation and lactation fed with canned food ad libitum: energy and protein intake, development of body weight and body composition

The NRC recommendations for cats for energy and protein supply during gestation and lactation are based on limited data. This study aimed to answer the question: Can the energy requirement be met with canned food or is the volume restrictive? Therefore, balance trials were conducted in 10 queens before mating, during the 4th and 7th week of gestation and during the 2nd and 6th week of lactation. The cats were fed with canned food ad libitum. Additionally, the body composition of the queens was measured by dual-energy X-ray absorptiometry (Dexa) before mating, after parturition and after weaning. Eight of 10 cats presented increased body fat content and lean body mass during gestation. The weight loss during lactation led to a loss of lean body mass, but only six cats lost body fat of widely differing amounts. It was evident that the queens' dry matter intake was consistent with that of queens fed ad libitum with dry food. The cats lost lean body mass during lactation and had negative protein balances in the 2nd week of lactation. This seems to be physiological in early lactation. Nevertheless, the protein recommendations for lactation seem to be too low.

Activities of leukocyte enzymes in cats during feeding different diets

The objective of the present study was to investigate the influence of diet composition on enzyme activities in feline leukocytes. In trial A, the enzyme activity was measured in six normal weight cats fed four cooked diets with varying protein, fat and carbohydrate contents and different protein sources. In trial B, six normal weight and six obese cats were fed on dry food of different protein and carbohydrate content. The enzyme activities did not show a distinct and consistent reaction to different diet compositions. Therefore, it is doubtful, if enzyme activities in feline leukocytes are an appropriate tool to examine the metabolic state or detect metabolic diseases in cats.

[Puppy feeding in Switzerland]

In this study breeders and owners of 8 different dog breeds (Beagle, Bernese Mountain Dog, Cavalier King Charles Spaniel, Great Dane, German Shepherd (GS), Labrador, Papillon, Sheltie) were interviewed to obtain information on puppy feeding in Switzerland. Besides answering a questionnaire (husbandry and feeding of the puppies), the participation in this study included weekly weighing of the animals as well as exact documentation of the amount fed to the animals. Totally 67 dog breeders and 131 new owners of puppies participated. The weight development of the puppies was mostly parallel to the growth curve in the GS, Labradors and Shelties. There were some substantial differences to the ideal growth curve within the other breeds. The daily mean energy requirement was estimated too high, when including the growth curves. 80 - 90 % of the recommendations would be sufficient for most animals. The calcium supply was in the range of tolerance in all breeds. Nearly all breeders used commercially available complete food while raising the puppies. No breed-specific differences could be shown.

Energy and protein needs of cats for maintenance, gestation and lactation

In the present investigation, data on the energy intakes and energy needs, as well as protein and fat accretion, of queens during pregnancy, during lactation and after lactation are given. Eleven adult cats were used as experimental animals. Data were collected during the fourth and seventh week of pregnancy, the second and sixth week of lactation and the second and sixth week after lactation. The cats were fed dry kitten food. During gestation and after lactation, all measurements were performed with respiration chambers. During lactation, balance trials without respiration chambers were performed. Body weight was measured and nitrogen, carbon and energy balances were calculated. From these, protein and fat accretion, as well as the metabolisable energy intake, was calculated. The weight gain during gestation was linearly independent of the number of kittens. During lactation, all cats lost weight; nevertheless, all cats except one were heavier 2 weeks after lactation than at mating. The energy intake of the cats during gestation was 1.8 times the maintenance requirement in the fourth week and two times maintenance requirement in the seventh week, and these energy intakes differed greatly among individuals. The energy intake of the cats during lactation was clearly higher than that recommended by National Research Council (NRC)(1), whereas the recommended protein intake in the second week of lactation was met. As the calculated protein balance was negative, the NRC recommendation for protein intake seems to be too low. In comparison to previous data, the cats showed a higher energy intake during lactation (median 502kJ/kgBW/d, second week lactation), and the weight loss was much lower. Further investigations on pregnant and lactating cats are necessary to complete the database.

Effect of vitamin E supplementation of sheep and goats fed diets supplemented with polyunsaturated fatty acids and low in Se

Vitamin E (VitE) and selenium (Se) are an essential part of the antioxidative functions of metabolism. There are situations of low supply of both micronutrients. As VitE is involved in ruminal biohydrogenation of polyunsaturated fatty acids (PUFA) and their protection against oxidation in metabolism, diets supplemented with PUFA may challenge VitE to an extent making recommended supplies insufficient. Twelve goats and sheep each were fed a diet supplemented with PUFA and characterised by low Se and limited VitE contents during the last 2 months of gestation and the first 2 months of lactation. The basal diet consisted of hay and concentrate. Six goats and sheep received extra VitE, while the control groups received no extra VitE. Blood and milk samples were taken. In addition, liver, heart muscle and spleen samples were obtained from the offspring after slaughtering at an age of 8 weeks. No significant changes were observed in serum Se and VitE. A significant increase in serum VitE concentrations between 2 and 4 weeks postpartum (pp) was evident in the supplemented kids. In 4, 6 and 8 weeks pp, the serum concentrations of VitE in the supplemented kids were significantly higher compared to the unsupplemented group. In the kids, VitE was higher in liver of the supplemented groups. There were no significant differences in response to extra VitE between sheep and goat. The kids responded to serum VitE different from that of lambs, as a significant difference was observed between supplemented and unsupplemented animals in the goat kids, but not the lambs. In conclusion, goats and sheep have to be viewed differently and may not be considered alike relating to VitE/Se metabolism and requirements, especially in young animals.

Additional data on energy requirements of young adult cats measured by indirect calorimetry

Measurements of nitrogen, carbon and energy balances were done on eight female adult cats aged approximately 1.5 years with the help of respiration chambers. The cats were fed with a marked dry food for kittens (Biomill kitten). Faeces and urine samples were collected with the help of a special cat toilet that allows the single collection of both materials. The calculated energy requirement of these eight female cats was 239.6 kJ ME/kg BW/day (R(2) = 0.98). Including the data, on 12 young male adult cats, of Läuger, (2001), an energy requirement of 238 kJ ME/kg BW/day (R(2) = 0.95) could be calculated. From these data, it can be followed that the energy requirements of young, active cats are higher than that of the older cats. The method of indirect calorimetry does not necessarily lead to lower energy requirements.

Mutations within the FGF5 gene are associated with hair length in cats

Hereditary hair length variability in mice and dogs is caused by mutations within the fibroblast growth factor 5 (FGF5) gene. The aim of this study was to evaluate the feline FGF5 orthologue as a functional candidate gene for the long hair phenotype in cats, which is recessive to short hair. We amplified the feline FGF5 cDNA and characterised two alternatively spliced transcripts by RT-PCR. Comparative cDNA and genomic DNA sequencing of long- and short-haired cats revealed four non-synonymous polymorphisms in the FGF5 coding sequence. A missense mutation (AM412646:c.194C>A) was found in the homozygous state in 25 long-haired Somali, Persian, Maine Coon, Ragdoll and crossbred cats. Fifty-five short-haired cats had zero or one copy of this allele. Additionally, we found perfect co-segregation of the c.194C>A mutation within two independent pedigrees segregating for hair length. A second FGF5 exon 1 missense mutation (AM412646:c.182T>A) was found exclusively in long-haired Norwegian Forest cats. The c.182T>A mutation probably represents a second FGF5 mutation responsible for long hair in cats. In addition to the c.194C>A mutation, a frameshift mutation (AM412646:c.474delT) was found with a high frequency in the long-haired Maine Coon breed. Finally, a missense mutation (AM412646:c.475A>C) was also associated with the long-haired phenotype in some breeds. However, as one short-haired cat was homozygous for this polymorphism, it is unlikely that it has a functional role in the determination of hair length.

Low molecular weight PLA: a suitable polymer for pulmonary administered microparticles?

Beclomethasonedipropionate (BDP)-containing microparticles were prepared by the solvent evaporation/extraction method. Different preparation parameters were optimized before investigations. Polylactic acid (PLA) and polylactic/glycolic acid (PLGA) with molecular weights of 2000 and 15,000 were used as matrix polymers. In all experiments the mean diameter of the microparticles was 1-5 microns with a drug content > or = 23 per cent. Microparticles of PLA, MW 2000, showed a prolonged and complete release over 8 h, whereas those of PLGA liberated only 20 per cent of the encapsulated drug within 8 h. BDP was determined by a validated reversed-phase HPLC method with a detection limit of 20 ng/ml. The encapsulated steroid seemed to be dissolved within the polymer, as differential scanning calorimetry suggested. Considering mean particle size, drug load, release characteristics and the status of the drug inside the matrix, the dosage form showed very good characteristics for inhalatory application. Surface characteristics of the microparticles were visualized by scanning electron microscopy (SEM). Although in vitro studies with human bronchial fluid resulted in a strong deterioration of microparticles, main structures were still visible by SEM after an incubation of 36 h in diluted bronchial fluid ex vivo. Degradation in phosphate buffered saline, protein solution and even in port liver esterase suspension resulted in minor effects on the particle surface.

Acute effects of liposome aerosol inhalation on pulmonary function in healthy human volunteers

Administering liposome-encapsulated drugs by aerosol is a feasible way of targeting drugs to the lungs. Prior to clinical application of aerosolized liposomes as drug carriers, their relative safety must be established. We evaluated the effects of inhaling nondrug-containing liposomes (15 and 150 mg of lipid per milliliter) for 1 h on pulmonary function and on oximetry in ten healthy nonsmoking volunteers. Spirometry was performed prior to and at intervals after inhalation, and subjects were monitored with pulse oximetry. Liposome inhalation was well tolerated, and no oxygen desaturation, decrements in pulmonary function, or side effects were noted. We conclude that inhalation of small particle aerosols of SPC liposomes produces no acute deleterious effects on pulmonary function in healthy subjects.

Sensitive liquid chromatography assay for the determination of amikacin in human plasma

A selective LC method with on-line post-column derivatization is described for the determination of amikacin in biological fluids. Chromatography was performed on a reversed-phase column, using pentane sulphonic acid as an ion-pairing reagent. For the analysis of biological fluids, amikacin and the internal standard tobramycin were extracted using an ion exchanger (Sephadex). Following complete removal of plasma proteins, the aminoglycosides were eluted with alkaline sodium sulphate solution and injected into the chromatograph. After chromatographic separation the eluent was mixed with the derivatization reagent (o-phthalaldehyde and mercaptoethanol in borate buffer pH 10.4) in a reaction coil at 50 degrees C. Detection was performed by fluorescence (excitation: 340 nm, emission: 418 nm). The overall run time was 8 min, at a flow rate of 1.2 ml min-1. The limit of quantification was 25 ng ml-1 for amikacin in plasma.