Greater Body Weight Gain Research Articles

Probiotics Reduce the Inflammatory Response Induced by a High-Fat Diet in the Liver of Young Rats

Nonalcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease in the pediatric population. Preliminary evidence suggests a potential therapeutic utility of probiotics for this condition. Here, we tested the potential effect of the probiotic VSL#3 (a multistrain preparation composed of Streptococcus thermophilus and several species of Lactobacillus and Bifidobacteria) on oxidative and inflammatory damage induced by a high-fat diet in the liver of young rats. At weaning, young male Sprague-Dawley rats were randomly divided into 3 groups (n = 6) fed a standard, nonpurified diet (Std; 5.5% of energy from fat) or a high-fat liquid diet (HFD; 71% of energy from fat). One of the HFD groups received by gavage VSL#3 (13 × 109 bacteria·kg−1·d−1). After 4 wk, the HFD rats had greater body weight gain, fat mass, serum aminotransferase, and liver weight than rats fed the Std diet. The HFD induced liver lipid peroxidation, tumor necrosis factor (TNFα) production, protein S-nitrosylation, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 expression, and metalloproteinase (MMP) activity. Moreover, in the HFD group, PPARα expression was less than in rats fed the Std diet. In rats fed the HFD diet and treated with VSL#3, liver TNFα levels, MMP-2 and MMP-9 activities, and expression of iNOS and COX-2 were significantly lower than in the HFD group. In VSL#3-treated rats, PPARα expression was greater than in the HFD group. A modulation of the nuclear factor-κB pathway by VSL#3 was also demonstrated. Our data suggest that VSL#3 administration could limit oxidative and inflammatory liver damage in patients with NAFLD.

Abstract 3710: Estrogen Does not Account for Accelerated Atherosclerosis in LDLr−/− Mice

Clinical studies demonstrate less atherosclerosis in pre-menopausal women compared to age-matched men, but an equalization in atherosclerosis burden and cardiovascular event rates between genders following menopause. Conversely, using the LDLR−/− mouse model we and others have previously demonstrated that young female mice develop accelerated atherosclerosis compared to age matched males. Whether this difference is due to sex hormones or differences in metabolic factors is not clear. To determine if estrogen mediated the alterations in atherosclerosis in the female mice, female mice were ovariectomized (Ovx). Ovx mice had a marked reduction in uterus weight (Sham: 86 ± 1 vs Ovx: 26 ± 1mg, P < 0.001) and both Ovx females and males had greater body weight gain when fed a lard-enriched diet (10% kcal from fat, D12451 , Research Diets) for 17 weeks compared to sham females. Ovariectomy resulted in an increase in fasting glucose concentrations, which was comparable to males. Cholesterol and triglyceride concentrations were higher in both sham and Ovx females compared to males; primarily distributed in increased VLDL and LDL particles. Interestingly, ovariectomy had no significant effect on extent of atherosclerotic lesion formation in female mice and the extent of atherosclerotic lesion area in both female groups was significantly increased compared to male mice. These data suggest that gender specific differences in lipids and atherosclerotic lesion formation in female LDL-R deficient mice fed a diet enriched in lard are not mediated by estrogen.

Impact of the earthworm Lumbricus terrestris on the degradation of Fusarium-infected and deoxynivalenol-contaminated wheat straw

When conservation tillage is practised in agriculture, plant residues remain on the soil surface for soil protection purposes. These residues should be widely decomposed within the following vegetation period as microbial plant pathogens surviving on plant litter may endanger the currently cultivated crop. Important soil-borne fungal pathogens that preferably infect small grain cereals belong to the genus Fusarium. These pathogens produce the mycotoxin deoxynivalenol (DON), a cytotoxic agent, in infected cereal organs. This toxin frequently occurs in cereal residues like straw. So far it is unclear if DON degradation is affected by members of the soil food web within decomposing processes in the soil system. For this purpose, a microcosm study was conducted under controlled laboratory conditions to investigate the degradation activity of the earthworm species Lumbricus terrestris when exposed to Fusarium-infected wheat straw being contaminated with DON. Highly Fusarium-infected and DON-contaminated straw seemed to be more attractive to L. terrestris because it was incorporated faster into the soil compared with straw infected and contaminated at low levels. This is supported by a greater body weight gain (exposure time 5 weeks) and smaller body weight loss (exposure time 11 weeks) of L. terrestris, respectively, when highly contaminated straw was offered for different time periods. Furthermore, L. terrestris takes part in the efficient degradation of both Fusarium biomass and DON occurring in straw in close interaction with soil microorganisms. Consequently, earthworm activity contributes to the elimination of potentially infectious plant material from the soil surface.

Effects of dietary fat inclusion at two energy levels on reproductive performance, milk compositions and blood profiles in lactating sows

This study was conducted to investigate the effects of dietary fat inclusion to create two energy levels on reproductive performance, milk compositions and blood profiles in lactating sows. Twenty-four multiparous sows were randomly assigned to four treatments according to a 2×2 factorial arrangement. Two energy levels (3365 and 3265 kcal/kg) were created by supplementing different fat levels (high and low). Higher energy level resulted in less (P<0.05) body weight and backfat loss, shorter wean-to-estrus interval, and greater body weight gain of piglets. Sows fed higher fat diet had higher (P<0.05) fat concentration in colostrum. Higher concentrations of triglyceride and creatinine and lower concentrations of luteinizing hormone at weanling were noted (P<0.05) in sows fed lower energy diet than those fed higher energy diet. In conclusion, feeding of higher energy diet during lactation may improve the reproductive performance of sows during lactation.

Diethylstilbesterol has Gender-Specific Effects on Weight Gain and Bone Development in Mice

Neonatal exposure to diethylstilbesterol (DES) in female mice programs estrogen-sensitive tissues, resulting in greater body weight gain and positive effects on bone architecture at adulthood. Using the CD-1 mouse model, the objective of the present study was to examine how short-term neonatal exposure to DES modulates weight gain as well as bone mineral density (BMD), bone strength, and bone microarchitecture in both males and females at adulthood. Male and female offspring (n = 8–12 pups/treatment/gender) were randomized to DES (2 mg/kg bw/d) or control (corn oil) from postnatal day 1 to 5 (subcutaneous injection, once daily) and sacrificed at 4 mo of age. Body weight was measured weekly, while bone mineral, strength, and microarchitecture were measured at 4 mo of age. DES treatment resulted in significantly higher body weight in females but lower weight in males at 4 mo of age. In DES-treated females, markedly higher BMD of lumbar vertebrae (LV1–LV3) was translated into significantly stronger LV2 that was more resistant to fracture; similar effects were observed at the femur midpoint. At the spine, males had a markedly lower BMD and peak load, suggesting an adverse effect. Microstructural analyses demonstrated that functional changes in femurs, i.e., peak load, were primarily due to modulation of cortical bone. In conclusion, neonatal exposure to DES exerted gender-specific effects on body weight gain and bone health.

Growth performance, nutrient digestibility and immune response of broiler chicks fed diets supplemented with a culture of Lactobacillus bulgaricus

AbstractBACKGROUND: Probiotics are being developed for use in animal feed to enhance production performance and prevention of gastrointestinal infections. The ban on using antibiotics as growth promoters, antibiotic resistance and the inherent problems of developing new vaccines make a compelling case for developing alternatives for in‐feed antibiotics. The alternatives of choice have to be considered under the environmental conditions of the animal. Among the probiotics in use today, Lactobacillus has been shown to play a vital role in disease prevention, immune enhancement, improved growth and carcass yield in poultry. The present study investigates the effect of Lactobacillus bulgaricus (LB)‐based probiotic on the growth performance, nutrient digestibility and immune response of broilers under tropical environmental conditions.RESULTS: Broilers fed LB diets consumed more feed (P &lt; 0.05) and had greater body weight gain than the control group. Feed/gain ratio improved significantly (P &lt; 0.05) with the 20, 40 and 60 mg kg−1 LB diets compared with the control or 80 mg kg−1 LB diet. The apparent digestibilities of nitrogen and fat increased with LB supplementation. However, there was no significant difference (P &gt; 0.05) in fibre digestibility. White blood cell count increased significantly in broilers fed higher levels (&gt;40 mg kg−1) of LB compared with the control group. Antibody production measured as antibody titre against Newcastle disease vaccine showed a curvilinear response over the range of LB concentrations examined.CONCLUSION: The results indicate that LB addition to broiler chick diets significantly improved growth performance, increased nutrient digestibility and stimulated humoral immune response. Copyright © 2008 Society of Chemical Industry

Comparison of Brown Midrib Sorghum-Sudangrass with Corn Silage on Lactational Performance and Nutrient Digestibility in Holstein Dairy Cows

Total mixed rations containing brown midrib sorghum-sudangrass silage (bmrSS) or corn silage (CS) at either 35 or 45% of dietary dry matter were fed to Holstein dairy cows to determine the effect on lactational performance and nutrient digestibility. Twelve cows were assigned to 1 of 4 diets in replicated 4×4 Latin squares with 21-d periods. In vitro 30-h neutral detergent fiber digestion, measured before the start of the trial, was 46.0% for CS and 58.3% for bmrSS. Dry matter intake was greatest when cows were fed the 35% CS (23.4 kg/d) and 45% CS (23.2 kg/d) diets, was least when cows were fed the 45% bmrSS diet (17.6 kg/d), and was intermediate when cows were fed the 35% bmrSS diet (20.1 kg/d). The bmrSS diets resulted in greater body weight gain per 21-d period but similar body condition scores compared with the CS diets. Yield of solids-corrected milk (SCM) was similar among the diets. Efficiency (SCM:dry matter intake) was 28% greater for cows fed the bmrSS than those fed the CS diets. In vivo digestibilities of organic matter and crude protein were greater for the CS diets than the bmrSS diets, but total tract digestibilities of neutral detergent fiber and starch were similar among diets. Ruminal pH was greater when cows were fed the 45% bmrSS diet (6.58), was least when cows were fed the 35% CS (6.10) and 45% CS diets (6.13), and was intermediate when cows were fed the 35% bmrSS diet (6.42). The ratio of acetate to propionate was greater for the bmrSS diets (2.77) than for the CS diets (2.41), with no difference among diets in total volatile fatty acid concentrations (122mM). In conclusion, cows fed bmrSS had greater efficiency of SCM production, higher ruminal pH, and greater acetate to propionate ratios than cows fed CS. With these diets fed in a short-term study, bmrSS appeared to be an effective alternative to the CS hybrid when fed at either 35 or 45% of dietary dry matter.

A new model for nonalcoholic steatohepatitis in the rat utilizing total enteral nutrition to overfeed a high-polyunsaturated fat diet

We have used total enteral nutrition (TEN) to moderately overfeed rats high-polyunsaturated fat diets to develop a model for nonalcoholic steatohepatitis (NASH). Male Sprague-Dawley rats were fed by TEN a 187 kcal.kg(-3/4).day(-1) diet containing 5% (total calories) corn oil or a 220 kcal.kg(-3/4).day(-1) diet in which corn oil constituted 5, 10, 25, 35, 40, or 70% of total calories for 21 or 65 days. Rats fed the 5% corn oil, 220 kcal.kg(-3/4).day(-1)diet had greater body weight gain (P < or = 0.05), fat mass (P < or = 0.05), and serum leptin and glucose levels (P < or = 0.05), but no liver pathology. A dose-dependent increase in hepatic triglyceride deposition occurred with increase in percent corn oil in the 220 kcal.kg(-3/4).day(-1) groups (P < or = 0.05). Steatosis, macrophage infiltration, apoptosis, and focal necrosis were present in the 70% corn oil group, accompanied by elevated serum alanine aminotransferase (ALT) levels (P < or = 0.05). An increase in oxidative stress (thiobarbituric acid-reactive substances) and TNF-alpha expression (P < or = 0.05) was observed in the 70% corn oil group, as well as an increase in hepatic CYP2E1 and CYP4A1 expression (P < or = 0.05). Significant positive correlations were observed between the level of dietary corn oil and the degree of pathology, ALTs, oxidative stress, and inflammation. Liver pathology was progressive with increased necrosis, accompanied by fibrosis, observed after 65 days of TEN. Increased expression of CD36 and l-fabp mRNA suggested development of steatosis was associated with increased fatty acid transport. These data suggest that intragastric infusion of a high-polyunsaturated fat diet at a caloric level of 17% excess total calories results in pathology similar to clinical NASH.

Disruption of the murine intestinal alkaline phosphatase geneAkp3impairs lipid transcytosis and induces visceral fat accumulation and hepatic steatosis

Intestinal alkaline phosphatase (IAP) is involved in the process of fat absorption, a conclusion confirmed by an altered lipid transport and a faster body weight gain from 10 to 30 wk in both male and female mice with a homozygous null mutation of the IAP coding gene (Akp3(-/-) mice). This study was aimed to delineate morphologically and quantitatively the accelerated lipid absorption in male Akp3(-/-) mice. Feeding a corn oil bolus produced an earlier peak of triacylglycerol in serum (2 vs. 4 h for Akp3(-/-) and wild-type mice, respectively) and an approximately twofold increase in serum triacylglycerol concentration in Akp3(-/-) mice injected with a lipolysis inhibitor, Triton WR-1339. A corn oil load induced the threefold enlargement of the Golgi vacuoles in male wild-type mice but not in Akp3(-/-) mice, indicating that absorbed lipids rarely reached the Golgi complex and that the transcytosis of lipid droplets does not follow the normal pathway in male Akp3(-/-) mice. Force feeding an exaggerated fat intake by a 30% fat chow for 10 wk induced obesity in both male Akp3(-/-) and wild-type mice, and therefore no phenotypic difference was observed between the two. On the other hand, the forced high-fat chow induced an 18% greater body weight gain, hepatic steatosis, and visceral fat accumulation in female Akp3(-/-) mice but not in female wild-type controls. These results provide further evidence that IAP is involved in the regulation of the lipid absorption process and that its absence leads to progressive metabolic abnormalities in certain fat-forced conditions.

Effects of stocking density and group size on the performance of white and brown Hyline layers in semi-arid conditions

The effect of housing two Hyline strains of commercial laying hens White Hyline (W-98) and Brown Hyline (Hyline Brown) at densities of 2, 3 or 4 per cage (1100, 733 or 550 cm2/hen, respectively) was investigated over 3 months. Hyline Brown layers gained more weight, laid more but lighter eggs, utilized feed more efficiently and had a lower mortality than W-98 layers. Housing birds 2 or 3 per cage resulted in greater body weight gain, higher egg production, heavier eggs, better feed conversion ratio and a lower mortality than housing them 4 per cage. There were significant interactions between strain and stocking density for egg production, egg weight, egg output and mortality. It is suggested that for egg production in semi-arid areas Hyline Brown hens could be used and housed at a density of 733 cm2/hen.

Pre-Conception Energy Balance and Secondary Sex Ratio—Partial Support for the Trivers-Willard Hypothesis in Dairy Cows

According to the Trivers-Willard hypothesis, maternal condition at or around conception affects the secondary sex ratio in mammals. However, there are little or no data available on indicators of maternal condition in dairy cows on the sex of the resultant offspring. A total of 76,607 body condition score (BCS; scale of 1 to 5) records and 76,611 body weight (BW) records from 3,209 lactations across 1,172 cows were extracted from a research database collated from one research herd between 1986 and 2004, inclusive. Exclusion of multiple births and cows with no information before calving (e.g., nulliparous animals) resulted in 2,029 records with BCS and BW observations from the previous calving, and 2,002 and 1,872 lactations with BCS and BW observations at conception and midgestation, respectively. Change in BCS and BW between calving and conception and between conception and midgestation was calculated per lactation. Generalized estimating equations were used to model the logit of the probability of a male calf, in which cow was included as a repeated effect with a first-order autoregressive correlation structure assumed among records within cow. Of the BCS variables investigated, there was a linear relationship between the logit of the probability of a male calf and BCS change between calving and conception, the rate of BCS change over this period (BCS divided by days in milk), and BCS at the calving event immediately before conception. The birth of a bull calf was 1.85 times more likely in cows that lost no BCS from calving to conception compared with cows that lost one BCS unit from calving to conception. This increase in odds was equivalent to a 14% unit increase in the probability of a male calf (from 54 to 68%). The amount of BW lost between calving and conception and the rate of loss affected the sex of the resultant offspring. Less BW loss or greater BW gain between calving and conception was associated with greater likelihood of a male calf. Results suggested a positive effect of pre-conception BCS and BW change on secondary sex ratio, agreeing with the Trivers-Willard hypothesis that females in good physiological condition are more likely to produce male offspring.

Second-Generation Antipsychotics

Six second-generation antipsychotics (SGAs), aripiprazole, clozapine, olanzapine, quetiapine, risperidone and ziprasidone, are currently US FDA approved. The aim of this review is to investigate whether sex differences exist for efficacy and adverse effects of these drugs.Sex-related differences have been shown in the pharmacokinetics of cytochrome P450 (CYP), with a higher activity in females for CYP3A4 and CYP2D6. However, even if there are pharmacokinetic differences between females and males, significantly higher plasma concentrations in women have been demonstrated only for olanzapine and clozapine. To date, sex differences in adverse effects have not been well studied, but some adverse effects such as weight gain, hyperprolactinaemia and cardiac effects are reported to be particularly problematic for women. Most of the studies reviewed indicate that clozapine and olanzapine are associated with greater bodyweight gain than the other atypical antipsychotics, and that serious adverse effects such as metabolic syndrome, which includes increased visceral adiposity, hyperglycaemia, hypertension and dyslipidaemia induced by SGAs, are more frequent in females. According to most studies, the risk for cardiac adverse effects induced by SGAs is the same in male and female patients. Although women are at a lower risk of sudden cardiac death, they have a higher risk of induced long QT syndrome from antiarrhythmic and, probably, antipsychotic drugs. The propensity of sexual dysfunctions is higher with conventional antipsychotics than with SGAs. Additionally, there is some evidence that female sexual dysfunction is associated with high prolactin levels; however, whether the degree of prolactin level elevation is different between female and male patients remains controversial. There is no evidence for sex differences for any of the SGAs to cause a higher rate of extrapyramidal symptoms, acute dystonia or any other movement disturbance. Knowledge of the risks and benefits associated with the use of SGAs during pregnancy and lactation is limited, although the direction of dose adjustments during pregnancy depends on the drug and the enzyme that is responsible for its metabolism. In general, data on sex differences were mostly obtained by posthoc analysis and, therefore, the conclusions that can be drawn are limited. For a better understanding of the basic mechanisms of sex differences, future studies with a primary focus on this topic are required. Data that are more specific will help determine the extent to which these differences will have implications for clinical management.

Targeted Intestinal Overexpression of the Immediate Early Gene tis7 in Transgenic Mice Increases Triglyceride Absorption and Adiposity

Following loss of functional small bowel surface area due to surgical resection, the remnant gut undergoes an adaptive response characterized by increased crypt cell proliferation and enhanced villus height and crypt depth, resulting in augmented intestinal nutrient absorptive capacity. Previous studies showed that expression of the immediate early gene tis7 is markedly up-regulated in intestinal enterocytes during the adaptive response. To study its role in the enterocyte, transgenic mice were generated that specifically overexpress TIS7 in the gut. Nucleotides -596 to +21 of the rat liver fatty acid-binding protein promoter were used to direct abundant overexpression of TIS7 into small intestinal upper crypt and villus enterocytes. TIS7 transgenic mice had increased total body adiposity and decreased lean muscle mass compared with normal littermates. Oxygen consumption levels, body weight, surface area, and small bowel weight were decreased. On a high fat diet, transgenic mice exhibited a more rapid and proportionately greater gain in body weight with persistently elevated total body adiposity and increased hepatic fat accumulation. Bolus fat feeding resulted in a greater increase in serum triglyceride levels and an accelerated appearance of enterocytic, lamina propria, and hepatic fat. Changes in fat homeostasis were linked to increased expression of genes involved in enterocytic triglyceride metabolism and changes in growth with decreased insulin-like growth factor-1 expression. Thus, TIS7 overexpression in the intestine altered growth, metabolic rate, adiposity, and intestinal triglyceride absorption. These results suggest that TIS7 is a unique mediator of nutrient absorptive and metabolic adaptation following gut resection.

Effect of Various Levels of Forage and Form of Diet on Rumen Development and Growth in Calves

The effect of form of starter grain (coarse vs. ground) and inclusion of various levels of hay on body weight gain and rumen development was evaluated. Two experiments were conducted to determine the effect of form of diet and forage inclusion on intake, growth, feed efficiency, and weaning age in dairy calves. Diets consisted of commercial coarse starter (C), ground starter (G), coarse starter with 7.5% bromegrass hay of consistent particle size (8 to 19mm) (H1), and coarse starter with 15% hay (H2). In experiment 1, intake was held constant across treatments until weaning, when feed was offered ad libitum. Calves receiving H1 and H2 were heavier and had greater body weight gain and greater feed efficiency than calves receiving C. There were no differences in intake. Total volatile fatty acid concentrations were higher, and the proportion of acetate was lower for calves fed G vs. C. In experiment 2, calves (n = 56) were offered diets on an ad libitum basis and weaned according to intake. There were no differences in body weight gain, average daily gain, feed efficiency, and age at weaning with respect to treatment. Starter and total dry matter intake tended to be greater in calves fed H1 and H2 vs. C. The addition of controlled particle size hay to diets of young calves appears to favorably alter rumen environment, resulting in increased intake and improved feed efficiency. Forage of a consistent particle size can be successfully utilized in starter rations of young calves.

Influence of Feed Form on Dietary Lysine and Energy Intake and Utilization of Broilers from 14 to 30 Days of Age

An experiment was conducted to evaluate the effects of feed form on lysine and dietary energy levels necessary for maximum body weight gain (BWG) and feed efficiency (FE) of male broilers from 14 to 30 d and to determine if birds realize a benefit in productive energy from consuming pelleted diets. A 2 x 3 x 2 factoria l treatment arrangement was achieved by feeding diets in two forms (mash and steam- conditioned pellets) with three levels of digestible lysine (0.85, 0.95 and 1.05 % of the diet) and two dietary energy levels (3050 and 3200 kcal ME/kg). Male broiler chicks were provided a nutritionally adequate diet (3100 kcal ME/kg and 22.7% CP) from 0-13 d. Four pens of 32 birds were fed each dietary treatment. Mean body weight and feed consumption were obtained at 14 and 30 d. Average feed intake (AFI) was used to calculate lysine conversion ratio and calories consumed per bird. Pellet-fed birds consumed significantly less digestible lysine (P=0.0061) to achieve the same amount of BWG as the mash-fed birds. Pellet-fed birds exhibited a linear increase in BWG (P=0.0188) with increasing lysine concentrations, while mash-fed birds did not display a growth response at digestible lysine levels greater than 0.85%. Birds fed 3200 kcal ME/kg diets had greater BWG (P=0.006) than those fed 3050 kcal diets. No feed form x dietary energy level interaction was observed for any parameter. Feed form had no effect on AFI (P=0.3784). These findings suggest that improved BWG obtained with pelleted diets may be the result of reduced energy expenditure during meal consumption, indicating that feed form may influence perceived nutrient needs.

Co-dependence of calcium and phosphorus for growth and bone development under conditions of varying deficiency

The purpose of this study was to quantify the effect of variation in calcium intake, with and without supplemental phosphorus, on growth and bone development in growing animals under conditions of varying calcium and phosphorus deficiency. Nine groups of weanling male rats were fed a diet nutritionally complete, except for calcium and phosphorus, for 28 days. This diet provided nine levels of varying calcium and phosphorus repletion, using either calcium carbonate, dicalcium phosphate, or tricalcium phosphate. Body weights and diet consumption were measured throughout the test period. At term, the femurs from each animal were weighed, measured for tensile strength, bone mineral content (BMC), and bone density, and analyzed for ash, calcium, phosphorus, and histology. As expected, at equivalent levels of calcium supplementation, the two phosphorus-containing salts promoted significantly greater improvement in all the bone variables measured, as well as greater body weight gain and diet and calcium utilization, compared to animals supplemented with calcium only. Histomorphometric analysis confirmed the results of the mineral analysis and showed the structural impact of the inadequate mineral intake. The mean values for ash weight, BMC, and tensile strength in the nine diet groups were well fit ( R 2 values ranging from 0.93 to 0.99) by multivariate models incorporating only the diet content values for calcium and phosphorus. In these models, the value for the phosphorus coefficient was three to sixfold larger than that for the calcium term, indicating a substantially greater effect of varying phosphorus intake than of varying calcium. These results demonstrate both the co-dependence of calcium and phosphorus in bone development and the importance of providing both minerals to support soft tissue and bone growth.

Feed Intake Patterns, Growth Performance, and Metabolic and Endocrine Traits in Calves Fed Unlimited Amounts of Colostrum and Milk by Automate, Starting in the Neonatal Period

Feed intake, growth performance, and metabolic and endocrine traits were studied in male calves fed unlimited (GrAL; n=7) amounts of colostrum for 3 d after birth and mature milk up to d 28 and were compared with calves fed commonly recommended amounts of colostrum and milk (GrRS; n=7). Calves were fed by automates, and software was available to continuously register the time points and amounts of ingested feed up to 11 d of age. Body weight was measured on d 1, 4, 7, 14, 21, and 28, and blood samples were taken on d 1, 2, 3, 7, 14, 21, and 28 to measure several metabolites and hormones. Feed intake of calves fed GrAL increased from d 1 to 4, then remained stable and was always higher than for calves fed GrRS. Total visits (visits with and without milk intake) were higher for GrRS than GrAL, but visits with milk intake were comparable between groups and meal sizes per visit with milk intake were greater in GrAL than in GrRS. Body weight gain was greater in GrAL than in GrRS in wk 1, but not later. There were significant group differences in plasma concentrations of albumin (GrRS>GrAL), nonesterified fatty acids (GrRS>GrAL), cholesterol (GrRS>GrAL; d 28), insulin (GrAL>GrRS), and cortisol (GrRS>GrAL), but not of immunoglobin G, urea, glucose, triglycerides, growth hormone, and glucagon. In conclusion, calves fed ad libitum were capable of ingesting very large amounts of colostrum and milk, even during wk 1 of life, accompanied by a greater body weight gain in GrAL in the first week, whereas in GrRS, the high number of visits without feed intake indicate that these calves reached no repletion. Compared with calves provided restricted amounts of feed, calves with free access to colostrum and milk were characterized by reduced plasma concentrations of nonesterified fatty acids and by a transiently enhanced insulin and reduced cortisol status.

Effects of Psoroptes ovis infection and its control with an ivermectin controlled-release capsule on growing sheep : 1. Evaluation of weight gain, feed consumption and carcass value

To evaluate the prophylactic and therapeutic effects of an ivermectin controlled-release capsule (IVM-CRC) on the productivity of growing sheep infested with Psoroptes ovis 24 male and 24 female Merino landrace lambs, 5–6 months old and weighing 21.2–35.0 kg, were used. Sixteen replicates of three animals were formed based on sex and Day 0 body weight. Within each replicate animals were randomly allocated to one of three groups: untreated control; IVM-CRC on Day 0; IVM-CRC on Day 84. For treatment an IVM-CRC for sheep weighing 20–45 kg was used which is designed to deliver ivermectin at a minimum dose of 20 μg/kg per day for 100 days. The lambs were infested with 50–60 P. ovis mites each on Days 14 and 21. Mites in skin scrapings were counted on Days 70, 84, 98, 112 and 126. Body weight and feed consumption were measured every 2 weeks from Day 0 to 126. The animals were slaughtered on Day 127 and their carcasses evaluated. The IVM-CRC treatment on Day 0 prevented the establishment of P. ovis. All untreated lambs became infested. The lambs treated with an IVM-CRC on Day 84 became mite-free from Day 112 onwards. The lambs treated on Day 0 had significantly ( p<0.05) greater body weight gain from Day 0 to 84 (13.9 kg) and Day 0 to 126 (20.9 kg) than the untreated controls (9.6 and 12.8 kg, respectively) and the sheep treated on Day 84 (8.4 and 14.9 kg, respectively). Feed consumption (Days 0–126) for sheep treated with the IVM-CRC on Day 0 was higher than for sheep treated on Day 84 ( p<0.05) and for the untreated controls ( p<0.1). The carcasses of sheep treated with the IVM-CRC on Day 0 had significantly ( p<0.05) higher warm and cold weights, carcass yield, rib eye area and back fat thickness than the untreated control group and the sheep treated with the IVM-CRC on Day 84. The sheep treated with the ivermectin CRC on either Day 0 or 84 had significantly ( p<0.05) better muscle scores and lower muscle pH 1 h post-slaughter than the untreated controls. There was no significant ( p>0.1) difference between warm and cold carcass weights, carcass yield and rib eye area between sheep treated on Day 84 and untreated controls.

Growing-finishing performance and carcass characteristics of pigs fed normal and genetically modified low-phytate corn.

A genetically modified corn hybrid homozygous for the lpa1 allele, containing low phytate (LP), and its nearly isogenic equivalent hybrid (normal) were compared in two experiments with growing-finishing swine. In Exp. 1, 210 barrows (27 kg) were allotted to one of six dietary treatments with two corn hybrids (LP and normal) and three P feeding regimens. There were five replicate pens (seven pigs/pen) per treatment. Treatments consisted of diets that were supplemented with P throughout the growing-finishing period (.2% P and .15% supplemental P during growing and finishing phases, respectively) or only during the growing phase (.2% supplemental P) or that were not supplemented with P throughout the growing-finishing period. Performance at the end of the growing phase was based on a 2 x 2 factorial arrangement of treatments with two corn hybrids and two levels of added P (0 and .2%). This resulted in 10 replicates for the treatments supplemented with .2% P. The finishing phase (73 to 112 kg) was a 2 x 3 factorial arrangement of treatments with the two types of corn and three regimens of added P during the finishing period. Breaking load (BL) and ash of the fourth metacarpal were evaluated from one pig/pen at the end of the growing phase and from all pigs after slaughter. Pigs fed the LP corn diet without added P had greater body weight gain, feed efficiency, BL, and ash content of the fourth metacarpal than pigs fed the normal corn diet without added P. Performance was similar between pigs fed the LP diet without added P and pigs fed LP and normal corn with added P. In Exp. 2, 1,092 gilts (34 kg body weight) were allotted by weight in a commercial facility to one of three treatments: 1) normal corn/soybean meal diet containing .29% and .22% available P during the growing and finishing phases, respectively; 2) LP corn/soybean meal diet with the same available P level as Treatment 1; and 3) same as Treatment 2 for 8 wk, then no inorganic P supplementation during the finishing phase. All pigs were slaughtered at approximately 122 kg. There were no significant differences in growing-finishing performance or BL among treatments. However, pigs fed diets containing LP corn possessed carcasses with less backfat and a higher percentage of lean (P < .01). These results confirm that the P in LP corn is available to the pig and suggest that pigs fed diets containing this genetically modified corn will have more desirable carcasses.

Effects of Lasalocid in Milk Replacer or Calf Starter on Health and Performance of Calves Challenged with Eimeria Species

Holstein bull calves (n = 48) were purchased from local sale barns at 3 to 7 d of age and were assigned randomly to a 2×2 factorial arrangement of lasalocid in milk replacer (0 or 80 mg/kg) and in calf starter (3 or 44 mg/kg of dry matter). On d 10 after arrival, calves were orally dosed with 100,000 Eimeria oocysts. Intakes of calf starter and milk replacer, body weight (BW), BW gain, excretion of fecal oocysts, and fecal scores were determined. Calves fed lasalocid in milk replacer consumed more calf starter, had greater BW gain, shed fewer oocysts in feces, and scoured less frequently and less severely than did calves fed no lasalocid or those fed lasalocid in calf starter alone. The combination of lasalocid in milk replacer and in calf starter did not improve performance above that of calves fed lasalocid in milk replacer alone. Low intake of calf starter prior to weaning may provide an insufficient amount of lasalocid to control effectively the effects of coccidiosis when calves are infected with Eimeria at an early age. Use of coccidiostats in milk replacers may reduce the effects of coccidiosis in young calves that are infected with Eimeria at an early age.