Internal Fat Deposits Research Articles

Effects of Immunocastration and Amino Acid Supplementation on Yearling Fallow Deer (Dama dama) Testes Development.

Forty-four fallow deer bucks (10 months old; 22.9 ± 2.4 kg) were utilized to investigate the effects of immunocastration and amino acid supplementation on testes development. Immunocastrated bucks were administered Improvac® at weeks 1, 8, and 20 of this study (control group: intact males). Starting at week 8, half of each sex received rumen-protected lysine and methionine (3:1) supplementation. At slaughter (week 37/39), body size, internal fat deposits, antler size parameters, testes weight, testes surface color, cauda epididymal sperm viability and morphology, and seminiferous tubule circumference and epithelium thickness were determined. Animals with larger body sizes, greater forequarter development, and antler growth also had greater testes development. Whilst the result of immunocastration on testes size is unexpected, testes tissue showed impaired development (atrophied seminiferous tubules), decreased sperm viability, and normal morphology. Testes tissue from immunocastrated deer was less red, possibly indicating reduced blood supply. Conversely, amino acid supplementation increased testes' redness and sperm viability, and intact males fed amino acids showed the greatest seminiferous tubule development. Thus, immunocastration may be a welfare-friendly alternative for venison production. Whilst the results support findings from the literature that testes size is not a reliable indicator of immunocastration success, this warrants further investigation in deer over different physiological development stages.

Relationships between body mass index, ultrasound measurements and, internal body fat depots in pelibuey sheep

The objective of this study was to evaluate the relationship between body mass index (BMI), ultrasound measurements (USM), and internal fat (IF) in hair sheep. The BMI and USM were determined 24 hours before laughter in 35 animals finished in intensive fattening. At slaughter, the IF (inner adipose tissue) was dissected, weighed, and grouped as mesenteric, omental, or perirenal fat; these three depots were summed to obtain their total weight. The relationship of the variables was evaluated through Pearson's correlation coefficient (r) using the CORR procedure and by regression models using the REG procedure of SAS ver. 9.3. The IF and BMI presented r= 0.75 (P <.0001), while the IF and USM presented an r that varied from 0.70 to 0.80 (P <.0001). Among the internal fat deposits, the perirenal was the one that presented minor correlation coefficients with BMI (r = 0.55), subcutaneous fat thickness (0.55), and thoracic Longissimus dorsi area) (r = 0.33), and for this, the last correlation was not significant (P>0.05). The regression equation between IF and BMI had a coefficient of determination (r2) of 0.67 (P <.0001). The inclusion of the subcutaneous fat thickness together with the BMI improved the r2 with a range of 0.77. The BMI and the subcutaneous fat thickness could be used to predict the weight of the internal fat in hair sheep.

Características de carcaça e componentes não-carcaça de tourinhos ½ Purunã x ½ Canchim alimentados com rações contendo três teores de concentrado

Improving the quality and energy content of rations increases performance in feedlot cattle, resulting in higher weight at slaughter, better carcass quality and a higher yield of non-carcass components. The purpose of this study was to evaluate the effect of increasing concentrate content in the ration on the carcass traits and weight of non-carcass components of young bulls finished in a feedlot. Eighteen young crossbred ½ Purunã x ½ Canchim bulls were used, with an average body weight (BW) of 278 kg and 12 months of age at the start of the experiment. The experimental design was completely randomized with three treatments and six replicates, where the treatments were the contents of 0.71, 0.97 and 1.24% BW day-1 of concentrate in the ration, on a dry matter (DM) basis. Corn silage was used as roughage and was provided ad libitum during the experiment. The young bulls were kept in the feedlot for 168 days and slaughtered at 17 months of age. There was a linear effect of concentrate content on the slaughter weight (SW) and hot carcass weight (HCW), which increased from 433 to 485 kg and from 248 to 280 kg between 0.71 and 1.24% BW in DM day-1 of concentrate. This represented an increase of 9.87 kg in SW and 6.16 kg in HCW for each 0.10% BW in DM day-1 of concentrate added to the ration. The hot carcass yield, rib eye area, subcutaneous fat thickness and the proportions of bone, muscle and fat in the carcass were not affected by the concentrate content and showed mean values of 57.3%, 79.6 cm2, 3.20 mm, 14.88%, 65.21% and 20.67%, respectively. There was a linear effect of concentrate content on the carcass temperature after cooling, which increased from 8.1 to 9.0 oC between 0.71 and 1.24% BW in DM day-1 of concentrate. An increase of 0.16 oC in the post-cooling carcass temperature for each 0.10% BW in DM day-1 of concentrate added to the ration was observed. The weight of internal organs and the perirenal and internal fat deposition were not affected by the concentrate content. The inclusion of 1.24% BW in DM day-1 of concentrate in the ration is recommended to obtain high SW and high HCW. Below this level, the carcass tissue composition and weight of non-carcass components are not modified.

Comparing the ability of anthropometric indicators in determining the prevalence of hypertension among Indian tribes

ObjectiveWe compared the ability of the selected anthropometric indicators to best predict the prevalence of hypertension among the Indian tribes. MethodsA cross-sectional study was undertaken among 1431 adult participants (705 males and 726 females) between the ages of 20 and 60 years from six major tribes in India. Selected anthropometric indicators such as body mass index (BMI), waist-hip-ratio (WHR), waist-height-ratio (WHtR), percentage body fat (PBF), visceral fat (VF), minimum-waist-circumference (MWC) and sum-of-the-four skinfold thickness (SF4), along with the physiological parameters such as blood pressure were recorded. Discriminant analysis (DA) was performed to examine and compare the ability of the selected anthropometric indicators towards classifying hypertension among males, females and the total population. ResultsSignificant independent association was observed for hypertension and similar conditions within gender and selected age-group categories. The overall hypertension prevalence among the studied tribes was observed at 12.6%. Standardized function coefficients (SFCs) in discriminant analysis revealed PBF(0.89, 0.36, and 0.76 for overall, males, and females respectively) as the most powerful discriminator of hypertension. In addition, visceral fat (0.74, 1.46, and 0.58 for overall, males and females respectively) was observed to be the other significant indicator of hypertensive blood pressure. These exploratory findings for the first time indicate fat deposition, rather than body density alone, as an emerging physiological and metabolic risk among Indian tribes. ConclusionIn the context of the highly prevalent chronic undernutrition, internal fat deposition is a major classifying factor of physiological and metabolic intolerance. It also indicates the increasing trend in lifestyle changes and the associated adversities among the Indian tribes.

Characterization of the lipid profile of internal fat deposits of sheep in the semiarid region of Brazil

The objective of this research was to quantify the internal fat deposits in Santa Inês sheep and to characterize the associated lipid profile. Forty-two male lambs, with a slaughter weight of 28.8±2.33kg and an average age of 7–8 months were used. Samples were collected from omentum, mesenteric, kidney and pelvic fat deposits. The fatty acids were separated by gas chromatography coupled with flame ionization detection. Chromatograms, with data on retention times and the percentages of the areas of fatty acid, were recorded using Peak software (ARI Instruments, USA). We observed that the omentum deposit had greater weight because it is the most active adipose tissue, i.e., the most sensitive to lipolysis because it covers the entire stomach in animals. Fourteen saturated fatty acids, ten monounsaturated fatty acids, and ten polyunsaturated fatty acids were identified. The fatty acids most commonly found in sheep were myristyl (C14:0), palmitic (C16:0), stearic (C18:0) and oleic (C18:1). The fatty acid profile of the fat deposits points to the possibility of using these fats in the formulation of the meat-derived product, an alternative that would add economic and nutritional value to these products.

Metabolic dysfunction following weight cycling in male mice.

BackgroundCombatting over-weight or obesity can lead to large fluctuations in an individual’s body weight, often referred to as weight cycling or “yo-yo” dieting. Current evidence regarding the potentially damaging effects of these changes is conflicting.MethodsHere, we assess the metabolic effects of weight cycling in a murine model, comprising three dietary switches to normal or high fat diets at 6 week intervals; male C57BL/6 mice were fed either a control (C) or high fat (F) diet for 6 weeks (n=140/group). C and F groups were then either maintained on their initial diet (CC and FF respectively) or switched to a high fat (CF) or control (FC) diet (n=35/group). For the final 6 week interval, CC and CF groups were returned to the control diet (CCC and CFC groups) while FC and FF groups were placed on a high fat diet (FCF and FFF) (n=28/group).ResultsFor the majority of metabolic outcomes changes aligned with dietary switches; however assessment of neuropeptides and receptors involved in appetite regulation and reward signalling pathways reveal variable patterns of expression. Furthermore, we demonstrate that multiple cycling events leads to a significant increase in internal fat deposition, even when compared to animals maintained on a high fat diet (Internal Fat: FCF: 7.4 ± 0.2g vs. FFF: 5.6 ± 0.2g; p<0.01).ConclusionsIncreased internal adipose tissue is strongly linked to the development of metabolic syndrome associated conditions such as type 2 diabetes, cardiovascular disease and hypertension. While further work will be required to elucidate the mechanisms underlying the neuronal control of energy homeostasis, these studies provide a causative link between weight cycling and adverse health.

Principal components analysis of the lipid profile of fat deposits in Santa Inês sheep

The aim of this research was to characterise the lipid profile of internal fat deposits in Santa Inês sheep and determine which variables have the greatest explanatory power on the total variation using principal components. Forty two male lambs were used, with a slaughter weight of 28.85±2.33kg and an average age of 7–8 months. Samples were collected from omentum, mesenteric, kidney and pelvic fat deposits. The fatty acids were separated in a gas chromatograph coupled to a flame ionization detector. The chromatograms, with the data on the retention times and the percentages of areas of fatty acids, were stored in Peak simply type software (ARI Instruments–USA). The first four principal components explained 68.03% of the total variation. Of the total 45 variables, 12 variables were the most relevant in the first 4 components, representing a significant reduction in the sample space, as almost 75% of the variables made small contributions to the total variance. The variables C140, C160, C171n7c, C18:0, C183n6, C203n3c, C204n6c, C23:0, monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), total unsaturated fatty acids (TUFA), saturated fatty acids (SFA), MUFA/SFA, TUFA/SFA, desirable fatty acids (DFA) and atherogenic index (AI) contributed the most to the total variation in the data.

Visceral adipose tissue mass in nonlactating dairy cows fed diets differing in energy density1

Our objective was to determine dietary energy effects on feed intake, internal fat deposition, body condition score (BCS), visceral organ mass, and blood analytes in Holstein cows. Eighteen nonpregnant, nonlactating cows (BCS=3.04±0.25) were blocked based on initial BCS and were randomly assigned within each block to 2 treatments. Treatments were either high energy [HE; net energy for lactation (NEL)=1.62 Mcal/kg] or low energy (LE; NEL=1.35 Mcal/kg) diets fed as total mixed rations for 8 wk. The LE diet consisted of 81.7% forage, including 40.5% wheat straw and 28.3% corn silage, whereas the HE diet contained 73.8% forage with no straw and 49.9% corn silage (dry matter basis). Cows were fed for ad libitum intake once daily at 0800h. Feed intake was recorded daily, blood was sampled at wk 1, 4, and 7, and BCS was assigned at wk 1, 4, and 7. Cows were killed following the 8-wk period, and visceral organs, mammary gland, and internal adipose tissues were weighed and sampled. The HE group had greater dry matter intake (15.9 vs. 11.2±0.5 kg/d) and energy intakes than cows fed LE, but neutral detergent fiber intake did not differ (5.8 vs. 5.6±0.25 kg/d for HE and LE). Final body weight was greater for cows fed HE (807 vs. 750kg), but BCS did not differ between groups (3.52 vs. 3.47 for HE and LE). Omental (26.8 vs. 15.2±1.6 kg/d), mesenteric (21.5 vs. 11.2±1.9kg), and perirenal (8.9 vs. 5.4±0.9kg) adipose tissue masses were larger in HE cows than in LE cows. Although subcutaneous adipose mass was not measured, carcass weight (including hide and subcutaneous fat) did not differ between HE (511kg) and LE (496kg). Liver weight tended to be greater for cows fed HE, but weights of gastrointestinal tract, heart, and kidney did not differ. Serum insulin tended to be greater and the glucose to insulin ratio was lower for cows fed HE. Serum concentrations of β-hydroxybutyrate and cholesterol were greater for HE cows than for LE cows but concentrations of glucose, nonesterified fatty acids, total protein, and albumin did not differ. Final BCS was correlated with masses of omental (r=0.57), mesenteric (r=0.59), and perirenal (r=0.72) adipose tissue, but mesenteric adipose mass increased more as BCS increased for cows fed HE. The similar final BCS between HE and LE cows demonstrates that BCS may lack sensitivity to detect differences in visceral fat deposition that might increase risk for peripartal diseases and disorders.

Nutritional Management of Transition Dairy Cows

Nutrition and management during late gestation impact peripartal health problems and influence subsequent milk production. Obesity at calving is a known risk factor for health problems and suboptimal production. Our evidence indicates that higher energy-density close-up diets do not increase subsequent milk production or energy balance. Our data indicate that even modest overfeeding results in changes analogous to obesity, with elevated insulin and NEFA and poor dry matter intake before calving, but substantial body fat mobilization, increased liver fat deposition, and prolonged increases in blood ketone bodies after calving. Modest energy excess during the dry period can lead to substantial internal fat deposition even without detectable changes in body condition. We conclude that requirements for energy (and other nutrients) should be met but not greatly exceeded during the dry period. This can be achieved by limit-feeding of moderate-energy diets or ad libitum feeding of high-roughage low-energy diets. Requirements for energy for dry cows and first-gestation heifers are modest (ca. 100 MJ ME or 14 Meal NE per cow daily) and can be met with relatively low-energy diets. Conversely, diets high in starch from corn silage or whole-crop cereals and supplemented with additional concentrates result in excess energy intake relative to requirements, as cows do not regulate intake to meet energy needs over the short-term. Dilution of those diets with low-quality roughages such as cereal straws can control energy intake to near cow’s requirements. Careful feeding management is critical to ensure that formulated nutrient intakes are actually achieved in practice.

Efeito da restrição pré e pós-natal sobre o crescimento dos depósitos de gordura de cordeiros Santa Inês

Avaliaram-se os efeitos da restrição pré e pós-natal sobre o tamanho e o crescimento dos depósitos de gordura de cordeiros Santa Inês. Foram utilizados 68 cordeiros, distribuídos em três tratamentos: com restrição pré-natal (RPRE), com restrição pós-natal (RPOS) e sem restrição (controle). Dentro de cada tratamento, os animais foram aleatoriamente sorteados para serem abatidos após o nascimento e com 10, 15, 25, 35 e 45kg de peso vivo. Os depósitos de gordura (omental, mesentérica, perirenal, pélvica e inguinal) foram registrados. Ao nascimento, os depósitos de gordura foram menores nos animais do tratamento RPRE. Entre 15 a 35kg de peso, a quantidade de gordura foi igual nos animais dos três tratamentos e, a partir desse peso (35kg), com exceção da gordura pélvica, os depósitos no animais do tratamento RPRE foram significativamente maiores. A restrição pré-natal elevou consideravelmente as taxas de ganho da gordura omental, mesentérica, perirenal e pélvica, enquanto a restrição pós-natal influenciou somente a taxa de ganho da gordura inguinal. Cordeiros de todos os grupos apresentaram taxas de desenvolvimento tardias (b&gt;1).

Comparison carcass traits of Azeri buffalo, native and crossbred (native * Holstein) male calves in west Azerbaijan-Iran

Iran has 500thousand heads buffalo that 80percent of them distributed in North and North West of Iran and they reared as multi purpose animals providing milk and meat. Farmer believe that buffalo milk had the best quality but because of huge and large head and skin buffaloes carcass isn’t suitable that governmental programmer pay a low facilities to buffalo fattener in comparison the cattle fattener thus the objective of this investigation was to the Comparison carcass traits of buffalo, native and Native cows* Holstein (NH) male calves that mostly fattened in this region. Eighty head claves (six heads of each treat) with average 160 kg body weight (BW) were fattened till the 300 kg. Ration and other environmental factors were the same. Three heads of each group’s according Iranian Standards slaughtered at abattoir. The slaughter weight, hot carcass weight, and the individual weights of the different slaughter by-products and organs were measured. The carcasses were chilled at 5o C for 24 h. One side of each carcass was cutting into wholesales cuts. Traits included Hot and cold carcass weight, bone, internal fat, meat, cut ability fat, dressing percent, wholesales cuts weight and percent. Wholesales cuts include neck, shoulder, loin, rib and flank and leg weight and percent. The results showed that there were not significant differences between hot and cold carcass weigh, meat, bone and cut ability fat percent. There were significant differences on internal fat, dressing percent and leg (P<0.05). The lowest and highest values for internal fat were observed buffalo and native carcass, respectively. In conclusion because of low internal fat deposition and high valuable wholesales cuts percent may buffalo carcass composition had a better quality in comparison cattle and fattening of buffalo is economically.

From heterogeneity to plasticity in adipose tissues: Site-specific differences

In mammals, two types of adipose tissues are present, brown (BAT) and white (WAT). WAT itself can be divided into subcutaneous and internal fat deposits. All these tissues have been shown to present a great tissue plasticity, and recent data emphasized on the multiple differentiation potentials obtained from subcutaneous WAT. However, no study has compared the heterogeneity of stroma-vascular fraction (SVF) cells and their differentiation potentials according to the localization of the fat pad. This study clearly demonstrates that WAT and BAT present different antigenic features and differentiation potentials. WAT by contrast to BAT contains a large population of hematopoietic cells composed essentially of macrophages and hematopoietic progenitor cells. In WAT, the non-hematopoietic population is mainly composed of mesenchymal stem cell (MSC)-like but contains also a significant proportion of immature cells, whereas in BAT, the stromal cells do not present the same phenotype. Internal and subcutaneous WAT present some discrete differences in the phenotype of their cell populations. WAT derived SVF cells give rise to osteoblasts, endothelial cells, adipocytes, hematopoietic cells, and cardiomyoblasts only from inguinal cells. By contrast, BAT derived SVF cells display a reduced plasticity. Adipose tissues thus appear as complex tissues composed of different cell subsets according to the location of fat pads. Inguinal WAT appears as the most plastic adipose tissue and represents a potential and suitable source of stem cell, considering its easy sampling as a major advantage for cell therapy.

Intake, growth and meat quality of steers given diets based on varying proportions of maize silage and grass silage

AbstractSimmental × Holstein-Friesian steers were offered four forage diets. These comprised grass silage (G); proportionately 0·67 grass silage, proportionately 0·33 maize silage (GGM); 0·33 grass silage, 0·67 maize silage (MMG); maize silage (M) from 424 (s.d. = 11·5) kg to slaughter at a minimum weight of 560 kg. Forages were mixed and offered ad libitum. Steers were offered 2 kg of a concentrate daily, the concentrate being formulated such that all steers had similar crude protein intakes across dietary treatments. A sample of steers was slaughtered at the beginning of the experimental period to allow the calculation of the rate of gain of the carcass and its components. Carcass dissection of a sample of steers allowed the development of a prediction equation of carcass composition based on thoracic limb dissection of all carcasses. Forage dry matter intake and live-weight gain increased linearly as maize silage replaced grass silage in the forage mixture, resulting in improvements in food conversion ratio (allP= 0·001). Killing-out proportion increased with maize silage inclusion (P&lt; 0·001) but fat and conformation scores did not differ significantly between diets. However, increasing maize inclusion in the diet resulted in a greater weight (P= 0·05) and proportion (P= 0·008) of fat in the carcass, and significant increases in internal fat deposition. The inclusion of maize led to a progressive increase in the daily gains of carcass (P&lt; 0·001), and significant increases in the daily gains of both fat (P&lt; 0·001) and lean tissue (P&lt; 0·001). Fat colour was more yellow in cattle given diets G and GGM than diets MMG and M(P&lt; 0·001) and colour intensity was lower on diet M than the other three diets (P&lt; 0·001). There were no significant differences in any aspects of eating quality between diets. Therefore, maize silage has the potential to reduce the time taken for finishing beef animals to achieve slaughter weight with no apparent detrimental effects on subsequent meat quality.

Deaths due to hunger strike: post-mortem findings

Hunger strike is described as voluntary refusal of food and/or fluids. Prolonged starvation may produce many adverse events including even death in rare circumstances. Here, we present three fatal cases (all males, 25–38 years) died from hunger strike. In all corpses, obvious muscle wasting with reduced subcutaneous and internal fat deposits, and atrophy in some organs were demonstrated at autopsy. The extraordinary long starvation period before death could presumably be linked to the thiamine uptake in this period, which had been discontinued by all subjects before the death occurred. Prolonged caloric deficiency with subsequent complications such as multiple organ failure, severe sepsis and ventricular fibrillation could account as major causes of death in these subjects. The competence of the physicians working with hunger strikers about the processes and potential problems is of great importance since they have to acknowledge about them to their patients.

Deaths due to hunger strike: post-mortem findings

Hunger strike is described as voluntary refusal of food and/or fluids. Prolonged starvation may produce many adverse events including even death in rare circumstances. Here, we present three fatal cases (all males, 25–38 years) died from hunger strike. In all corpses, obvious muscle wasting with reduced subcutaneous and internal fat deposits, and atrophy in some organs were demonstrated at autopsy. The extraordinary long starvation period before death could presumably be linked to the thiamine uptake in this period, which had been discontinued by all subjects before the death occurred. Prolonged caloric deficiency with subsequent complications such as multiple organ failure, severe sepsis and ventricular fibrillation could account as major causes of death in these subjects. The competence of the physicians working with hunger strikers about the processes and potential problems is of great importance since they have to acknowledge about them to their patients.

Relationships between body condition score, body weight and internal fat deposits in Latxa ewes

AbstractThe relationships between body weight (BW), body condition score (BCS) and internal fat deposits were studied in Latxa dairy ewes. In 2 years, the BW and BCS of 20% of the ewes in 14 flocks were recorded at the beginning of the mating period (pre-mating), and in the 1st month of lactation (post lambing). BW increased with age (BW = 54·05 × (1-e−0·988 × age), and the mature weight was not reached until 4 years, after which weight did not differ between pre-mating and post-lambing periods. Body condition score, however, differed between the two periods. The regression coefficients (b) of BW on BCS, when flock-year and age were included in the regressions, differed significantly (P &lt; 0·05) in the pre-mating and post-lambing periods, and were 5·3 (s.e. 0·31) and 6·3 (s.e. 0·43) kg per unit BCS, respectively. The correlation coefficients (r) were 0·77 and 0·71 respectively, compared with 0·42 and 0·38 when the flock-year and age of the ewes were not included in the regression.Thirty-seven of these ewes, with BCS between 0·75 and 4·00, were slaughtered, the weights of omental, mesenteric and kidney and channel fat recorded, and the lumbar fat thickness assessed at the last rib. The regressions between the weight of fat deposits and lumbar fat thickness and BW and BCS fitted to semi-logarithmic equations, except for mesenteric fat, in which the relationship was linear. Body condition score was a better predictor than BW for individual fat deposits, with proportionately 0·81 to 0·83 of the variation in the weight of the deposits accounted for by variation in BCS and 0·57 to 070 by variation in BW.

Allocation of Growth in Food-Stressed Atlantic Puffin Chicks

ABsmAcr.-In long-lived seabirds that lay a single-egg clutch, allocation of growth to certain body parts may be advantageous for the chick if food is limited. To investigate this, 40 Atlantic Puffin (Fratercula arctica) hatchlings were distributed in seven groups that were raised on different amounts of food to 38 days of age. When food intake was reduced, growth rates were depressed for all characters measured (i.e. body mass and length of the wing, 2nd primary, forearm, head + bill, culmen, skull, tarsus, and middle toe). Head and wing parts grew preferentially relative to the other characters, and onset of growth was delayed in the primaries. All chicks accumulated significant amounts of subcutaneous fat, whereas internal fat deposits were present only in the chicks that received the most food. Received 14 July 1995, accepted 20 March 1996.

Human adipocytes express alpha 2-adrenergic receptor of the alpha 2A-subtype only: pharmacological and genetic evidence.

In the present study we have reinvestigated the subtype of alpha 2-adrenoceptors expressed in human adipocytes (from subcutaneous and internal fat deposits) by means of radioligand binding using subtype-selective antagonists, and RNase mapping using a set of specific probes prepared from human alpha 2-adrenoceptors genes (alpha 2C2, alpha 2C4 and alpha 2C10). Comparison of the pharmacological properties of the human adipocyte alpha 2-adrenoceptors with those of the different human adrenoceptors expressed in COS-7 cells demonstrated that: i) human adipocyte alpha 2-adrenoceptors displays a KD for [3H]RX821002 and [3H]MK912 identical to that found in COS-7 cells transfected with the alpha 2C10 gene; ii) yohimbine and oxymetazoline is 1,000-fold more potent than prazosin to inhibit [3H]antagonist binding. RNase protection assays on cellular RNA prepared from the three fat deposits showed the presence of substantial amounts of alpha 2C10 transcripts: in contrast, mRNAs from alpha 2C2 and alpha 2C4 genes were undetectable. Altogether these results definitively establish that human adipocytes express only one alpha 2-adrenoceptor which is of the alpha 2A-subtype and encoded by the alpha 2C10 gene.

Characteristics of the Wolf (&lt;i&gt;Canis lupus labradorius&lt;/i&gt; Goldman) in Northern Quebec and Labrador

Two hundred and twelve wolves (Canis lupus labradorius) shot by hunters in northern Quebec and Labrador during the winters of 1976-77 through 1983-84 were examined for various population parameters. An estimated annual adult survival rate of 55% and a recruitment rate of 49% suggest a population of moderate exploitation. The sex ratio did not differ significantly from 1:1. Fifty-five percent of yearling females were pregnant or in breeding condition. The average litter size for all females was 6.8. Internal fat deposits were greatest in young males and older females. Caribou (Rangifer tarandus caribou) was the most common food item found in stomachs. A sample of caribou killed by wolves in the winter showed a selection for older-aged caribou with fat deposits slightly below that of the general population.Key words: wolf, caribou, northern Quebec, Labrador, predation

Effects of castration and subdermal silastic implants containing oestradiol-17 β-dipropionate on feedlot performance and carcass characteristics of male cattle

ABSTRACTFeedlot performance and carcass characteristics were examined in bulls and steers with and without a subdermal Silastic capsule containing oestradiol-17β-dipropionate. Castration and/or oestrogen treatment was imposed at approximately 8 months of age. The implants were removed 56 days before slaughter, i.e. 140 days after the trial commenced. Bulls gained more rapidly (12·9%), converted food to live-weight gain more efficiently (18·0%) and yielded leaner carcasses than did steers (P &lt; 0·05). The oestrogenic implant elevated serum oestradiol concentrations substantially (&gt; ninefold) over that of bulls and steers and induced a castration-response in the former. Serum luteinizing hormone, testosterone and testicular growth were suppressed (P &lt; 0·05) during the first 140 days of the trial in bulls, but returned to normal following implant removal. This response was paralleled by a reduction in average daily gain (P &lt; 0·05) and food: gain ratio (P &lt; 0·10). Contrary to expectations, average daily gain and food: gain ratio were not significantly improved in implanted steers. Oestrogen treatment reduced hot carcass weight, loin eye area and quality grade in both bulls and steers; the last as a result of decreased marbling and internal fat deposition. Results of this study suggest that excessive oestrogen as provided in this study via the implant fails to improve feedlot performance and carcass merit in steers and may, in fact, diminish the inherent anabolic attributes of the intact male. Additional studies are required to understand the complex interactions of androgens and oestrogens in the regulation of body growth and composition of male cattle.