Piglet Body Weight Variation and the Influence of Birth Weight on Piglet Growth During Lactation and Weaning

Summary Piglets are an important category in pig farming which should, alongside sows, be considered essential production heads. Over the past decades, the intensive selection in pig production has given priority to economically important traits resulting in greater feed utilization and obtaining more piglets from fewer sows. However, such selection practices have failed to improve the overall vitality of piglets and their ability to survive immediately after birth or during their stay in the farrowing unit. Body weight is of great importance in pig production, especially the piglet body weight at birth. A number of parameters can be predicted according to the piglet birth weight: mortality and growth rate, the physiological status of the heard, sensitivity to external influences, vitality and etc. The purpose of this paper is to determine the piglet body weight variation from birth to weaning (measured at birth, 3 hours after birth, 24 hours after birth and at weaning) and to examine the relationship between the birth weight of piglets and their body weight during the transition into nursing. A total of 105 piglets were enrolled in this study from the F1 generation sows followed through eight consecutive parities. The paper presents the results obtained using descriptive statistics, as well as variance and correlation analysis. The relationship between the piglet body weight at different stages of their life and overall production parameters was found to emphasize the centrality of housing conditions as the piglet weight at birth exerts a great impact on the body weight of older piglets, especially in the first days of the piglet life. Therefore, the proper care of piglets in farrowing units is of paramount importance to pig production, especially because piglets have lower body weight at birth nowadays than before.

PSIV-15 Determining the effects of increasing levels of xylanase in nutrient adequate diets on growth performance, carcass characteristics of growing-finishing pigs

A total of 1,944 mixed sex growing-finishing pigs (PIC; 337×1050; initial BW of 22.5±0.53 kg) were used in a 131-d growth trial to determine the effects of increasing levels of xylanase in adequate diets on grow-finish pig growth performance and carcass characteristics. The 6 dietary treatments consisted of corn, soybean meal, and dried distillers grains with solubles with added xylanase (Belfeed B 1100 MP; Jefo Nutrition Inc., Saint-Hyacinthe, Quebec) formulated to: 0, 5, 10, 20, 40, and 75 of enzymatic activity for xylanase (IU/kg) with 27 pigs per pen and 12 replicates per treatment. Data were analyzed as a randomized complete block design using lmer function in lme4 package in R with pen considered as the experimental unit, body weight as blocking factor, and treatment as a fixed effect. From d 0 to 70, there was a tendency (quadratic, R=0.068) for average daily gain (ADG) to decrease and then increase with increasing added xylanase, but there was no evidence (R >0.10) of differences for average daily feed intake (ADFI) and feed efficiency (G/F). From d 70 to 131 and overall, there was no evidence of difference (R >0.10) observed for ADG, ADFI, and F/G. There was no evidence for difference (R >0.10) between treatments for number of pigs receiving injectable treatments or mortalities. For carcass traits, increasing xylanase increased then decreased (quadratic, R=0.010) percentage carcass yield. Also, as xylanase increased, percentage lean decreased (linear, R=0.038) and backfat marginally increased (linear, R=0.066). In conclusion, adding increasing levels of xylanase in nutrient adequate diets did not influence growth performance or mortality but did improve carcass yield when intermediate levels were fed.

207 Improving Performance of Finishing Pigs with Added Val, Ile, and Trp: Validating a Meta-analysis Model

Based on a recent meta-analysis, we hypothesized that increased dietary Val, Ile, or Trp could correct possible amino acid interactions caused by high dietary Leu in diets containing high levels of corn protein, namely dried distillers grains with solubles (DDGS). A total of 1,200 pigs (PIC TR4×(Fast LW×PIC L02); initially 33.6±0.63 kg) were used in a 103-d study. The 6 dietary treatments were corn-soybean meal-DDGS-based diets as follow: low level of Lys-HCl (SBM), high Lys-HCl and moderate Ile, Val, Trp (NC; AA above NRC 2012 estimates), moderate Lys-HCl and high Ile, Val, Trp (PC), and PC with either increased L-Val (Val), L-Ile (Ile), or L-Trp (Trp). Diets contained 30% DDGS until pigs reached approximately 100 kg and then 20% DDGS until market. Data were analyzed as a randomized complete block design using lmer function in lme4 package in R with pen considered as the experimental unit, body weight as blocking factor, and treatment as a fixed effect with 10 replicates/treatment. Overall final BW and ADG were greater for pigs fed SBM, Val, and Ile diets than the NC with PC and Trp intermediate. Pigs fed the Val diet had greater (R< 0.05) ADFI than the NC with pigs fed SBM, PC, Ile, and Trp intermediate. No differences were detected between treatments for G:F. In conclusion, increasing Val or Ile in high Lys-HCl-DDGS-based diets improved growth performance and final BW compared with pigs fed diets containing high levels of HCl-Lys without added Val and Ile. These results demonstrate that negative effects of high Leu in corn-DDGS-based diets can be overcome by increasing the ratios of Val and Ile to Lys.

Abstract 326: Comparison of Patients’ Subjective Sense of Well Being and Their Cardiopulmonary Exercise Test Results

Introduction: The cardiopulmonary exercise test (CPET) helps assess exercise tolerance in patients. The CPET is a better predictor of general health status and functional capacity (fc) when compared with resting cardiac and pulmonary function testing measurements (1). The test makes use of a bicycle ergometer with the patient being fitted with ECG leads, blood pressure cuff, pulse oximeter, and a face mask which determines the amount of oxygen consumed and carbon dioxide released. The predicted peak oxygen consumption per unit body weight per unit time (VO2max) is calculated based on patient’s sex, age, weight and height (2). Fc is measured as a percentage of VO2max that was actually consumed. Objective: Our study evaluates any relationship between the CPET fc results and patient’s sense of overall well-being, which provides a subjective measure of their quality of life. Methods: In this retrospective study, we randomly selected 299 patients who visited the clinic using electronic medical records from May-June 2019. There were 260 females and 39 males, with ages between 16-82 years. Patient history was analyzed to look for “overall health rating” scores; how they felt about their overall health on a scale of 1 to 10, with 1 denoting feeling the worst and 10 indicating feeling the best of their health. Their CPET fc results were analyzed at the same time, where values <55% meant severely reduced fc, ≥55% but <70% meant moderately reduced fc, ≥70% but <80% meant mildly reduced fc, and ≥80% meant normal fc. Logistic regression was used to look for an association between the values of the overall health rating and CPET fc results, where patient’s age and sex were used as control variables. Results: With each score increase in the overall health rating, the odds of the fc value being normal than being mildly/moderately/severely reduced increases by 1.2 times, given the patient sex and age remain constant (95%CI (0.76,0.98), p = 0.019<0.05). Conclusion: The results reveal a statistically significant association between the patients' overall health rating and their CPET fc results. The higher the numerical value of the overall health rating and the better the patients feel about their health, the greater the probability that the patient will also have a better CPET fc result. Thus the CPET fc can be used as an objective value to assess a patient’s overall well being.

Reduction of Resting Energy Expenditure and Sarcopenic Obesity in Adults with Overweight and Obesity: A Brief Report

Background and Aim: The last decade has seen the emergence of a new condition, describing the coexistence of obesity and sarcopenia, termed Sarcopenic Obesity (SO). The aim of this study was to assess the potential association between SO and reduced Resting Energy Expenditure (REE). Methods: Body composition and REE were measured using a bioimpedance analyser (Tanita BC-418) and Indirect Calorimeter (Vmax Encore 229), respectively in 89 adults with overweight or obesity of both genders, referred to the Outpatient Clinic of the Department of Nutrition and Dietetics at Beirut Arab University (Lebanon). Participants were then categorized on the basis of having SO or not. Results : Thirty-nine of the 89 participants met the criteria for SO (43.8%), and these participants displayed a significantly lower REE per unit body weight than those in the group without SO (19.02 ± 2.26 vs. 20.87 ± 2.77; p = 0.001). Linear regression analysis showed that the presence of SO decreases REE by 1.557 kcal/day for each kg of body weight (β = -1.557; CI = -0.261 – (-0.503); p = 0.004), after adjusting for age and gender. Conclusion : SO appears to be present in a high proportion of treatment-seeking adults with overweight or obesity of both genders, and it seems to be associated with a reduced REE, compared with those without SO. Future studies are needed to clarify whether this may influence clinical outcomes.

Is energy expenditure reduced in obese mice with mutations in the leptin/leptin receptor genes?

Rodents with mutations in the leptin, or leptin receptor, genes have been extensively used to investigate the regulation of energy balance and the factors that underlie the development of obesity. The excess energy gain of these mutants has long been considered as being due in part to increased metabolic efficiency, consequent to reduced energy expenditure, but this view has recently been challenged. We argue, particularly though not exclusively, from data on ob/ob mice, that three lines of evidence support the proposition that reduced expenditure is important in the aetiology of obesity in leptin pathway mutants (irrespective of the genetic background): (i) milk intake is similar in suckling ob/ob and +/? mice; (ii) ob/ob mice deposit excess energy when pair-fed to the ad libitum food intake of lean siblings; (iii) in several studies mutant mice have been shown to exhibit a lower RMR ‘per animal’ at temperatures below thermoneutrality. When metabolic rate is expressed ‘per unit body weight’ (inappropriately, because of body composition differences), then it is invariably lower in the obese than the lean. It is important to differentiate the causes from the consequences of obesity. Hyperphagic, mature obese animals weighing 2–3 times their lean siblings may well have higher expenditure ‘per animal’, reflecting the costs of being larger and of enhanced obligatory diet-induced thermogenesis resulting from the increased food intake. This cannot, however, be used to inform the aetiology of their obesity.

Effects of emphysema on diaphragm blood flow during exercise

Chronic hyperinflation of the lung in emphysema displaces the diaphragm caudally, thereby placing it in a mechanically disadvantageous position and contributing to the increased work of breathing. We tested the hypothesis that total and regional diaphragm blood flows are increased in emphysema, presumably reflecting an increased diaphragm energetic demand. Male Syrian Golden hamsters were randomly divided into emphysema (E; intratracheal elastase 25 units/100 g body wt) and control (C; saline) groups, and experiments were performed 16–20 wk later. The regional distribution of blood flow within the diaphragm was determined by using radiolabeled microspheres in hamsters at rest and during treadmill exercise (walking at 20 feet/min, 20% grade). Consistent with pronounced emphysema, lung volume per unit body weight was greater in E hamsters (C, 59.3 ± 1.8; E, 84.5 ± 5.0 ml/kg; P < 0.001) and arterial[Formula: see text] was lower both at rest (C, 74 ± 3; E, 59 ± 2 Torr; P < 0.001) and during exercise (C, 93 ± 3; E, 69 ± 4 Torr; P < 0.001). At rest, total diaphragm blood flow was not different between C and E hamsters (C, 47 ± 4; E, 38 ± 4 ml ⋅ min−1 ⋅ 100 g−1; P = 0.18). In both C and E hamsters, blood flow at rest was lower in the ventral costal region of the diaphragm than in the dorsal and medial costal regions and the crural diaphragm. During exercise in both C and E hamsters, blood flows increased more in the dorsal and medial costal regions and in the crural diaphragm than in the ventral costal region. Total diaphragm blood flow was greater in E hamsters during exercise (C, 58 ± 7; E, 90 ± 14 ml ⋅ min−1 ⋅ 100 g−1; P = 0.03), as a consequence of significantly higher blood flows in the medial and ventral costal regions and crural diaphragm. In addition, exercise-induced increases in intercostal ( P < 0.005) and abdominal ( P < 0.05) muscle blood flows were greater in E hamsters. The finding that diaphragm blood flow was greater in E hamsters during exercise supports the contention that emphysema increases the energetic requirements of the diaphragm.

Maximum single leg force production: cockroaches righting on photoelastic gelatin

Integrating studies of mechanics, neural control and isolated muscle function are possible using arthropod legs. To evaluate leg performance, we measured the ground reaction forces generated by individual legs of the six-legged cockroach Blaberus discoidalis (3.1 g), during an emergency behavior, righting or over-turning. We used a photoelastic method to measure the forces generated by individual legs simultaneously. A gelatin track placed between crossed polarizing filters was illuminated from below, and a high-speed video camera recorded the stress-induced optical signals from above. The size and skew of the optical patterns were found to be related to the magnitude and direction of the force. We discovered that the ground reaction forces generated during the righting behavior of the death-head cockroach were eight times greater than those observed during high-speed running, supporting the possibility that relative leg forces (leg force per unit body weight) during running and maximal leg activity differ more in small arthropods than in larger vertebrates. Non-geometric scaling of relative leg force (i.e. scaling to less than body mass-0.33), along with the reduced force-generating ability of a single leg in animals with many legs, may help to explain why the maximum relative leg force production by six-legged cockroaches, as well as by some other small insects, can be similar to the relative single leg forces produced by two- and four-legged vertebrates that are almost 1000 times more massive. Leg number and body mass alone, however, appear to be insufficient to explain the variation observed in relative leg force production at a given body mass, because enormous diversity in musculo-skeletal parameters exists. The maximal relative leg force of the cockroach B. discoidalis during righting was at the low end of a 100-fold variation observed for smaller insects wedging (pushing through a small crevice) and pulling loads. Thus, this cockroach can be characterized as a moderately strong insect with the capacity for relatively high speed. Results from the present study question the predictive strength of the simple geometric scaling arguments involving a strength:weight ratio as they are applied to small arthropods and encourage further consideration of the importance of leg number, muscle force production and mechanical advantage in the derivation of general principles of leg performance.

Estimates of food intake using slow-release devices and carcass composition of Angus cows from a control line and a line selected for increasing yearling weight

Data from cows in two Angus lines, established in 1971 and comprising a yearling weight selection line (AS1) and its contemporary control (ACO), were recorded over three periods per year to estimate food intakes at pasture in a 3-year study begun in 1991. In each period, daily organic matter intake (DOMI) was estimated using chromic oxide slow-release devices. In total, 126 cows were included over an average of 2.6 periods each. Forty-six cows were slaughtered after weaning to determine if there were any line differences in body composition. The repeatability of DOMI estimates was 0.46�0.04, whilst the value between cows was 0.24�0.05. The AS1 cows were 15.0% heavier and ate 10.5% more than the ACO cows (P < 0.001). Estimated intakes per unit body weight or per unit metabolic body weight did not differ between lines. Adjusted calf weaning weights at 6 months of age per unit DOMI of the dam were 20.2 and 19.4 kg/kg respectively ( P < 0.05), a 4.1% increase by the AS1 line. The AS1 cows had 17.7% (P < 0.001) heavier carcasses than ACO cows. When adjusted to equal hot carcass weight on a log-log basis, AS1 cows had significantly more bone and less fat ( P < 0.01) than ACO cows. Kidney weights, but not heart or liver weights, were significantly greater for AS1 cows than for ACO cows (P < 0.01) when adjusted to a constant empty live weight. It was concluded that the cow-calf pairs in the AS1 line had a 4% greater calf weaning weight per unit of DOMI by cows than those in the ACO line, and differences were associated with cows which had relatively larger kidneys, more % bone and less % carcass fat soon after weaning.

Phosphorus-31 nuclear magnetic resonance spectroscopy of liver from two broiler chicken lines

Hepatic levels of phosphorus-containing compounds that are related to fat metabolism in the liver of two broiler lines with different body-fat content were assessed using high-resolution 31P NMR spectroscopy. PCA extracts of livers from 16-d-old chicks were analyzed with an NMR spectrometer. The results demonstrated that the concentrations of G3P, AMP and phosphocholine were significantly higher in the livers of LL birds than in those of the FL birds (P < 0.05). Differences in hepatic concentration of GPE and GPC were not detected between the two lines. It was also found that the liver weight per unit body weight of the FL chickens was less than that of the LL birds (P < 0.01). Average body weight of FL birds at 16 d of age was lighter than that of LL birds (P = 0.01). The FL birds deposited more (P < 0.05) fat per unit body weight than the LL birds. However, no statistical difference (P > 0.05) was found in protein deposition per unit body weight between the two lines. These results indicate that liver size and the concentration of hepatic phosphorus containing compounds are related to the partition of energy in broiler chickens. Key words: NMR spectroscopy, phosphorus-containing compounds, fat deposition, liver, broiler chicken