Kendall Swanson - Academia.edu (original) (raw)
Papers by Kendall Swanson
Canadian Journal of Animal Science, 2016
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To determine the effects of maternal nutrient restriction and re-alimentation on fetal liver and ... more To determine the effects of maternal nutrient restriction and re-alimentation on fetal liver and muscle development, 48 pregnant ewes with singletons, were fed a control diet [100% National Research Council (NRC) requirements (CON)] starting at the beginning of gestation. On day 50 of gestation, ewes (n = 7) were euthanized and fetal liver and skeletal muscle samples were collected. The remaining animals were fed either CON or 60% NRC requirements (RES), a subset were euthanized at day 90 of gestation (n = 7/treatment), and fetal samples obtained. Remaining ewes were maintained on the current diet (CON-CON, n = 6; RES-RES, n = 7) or switched to alternative diet (CON-RES, RES-CON; n = 7/treatment). On day 130 of gestation, remaining ewes were euthanized, and fetal samples collected. Fetal liver was analyzed for general tissue morphology, and fetal skeletal muscles were analyzed for lipid accumulation. mRNA expression of growth and metabolic factors were quantified in liver and muscle...
Bookmarks Related papers MentionsView impact
Biology of Growing Animals
Publisher Summary This chapter explains how diet and post-ruminal nutrients influence pancreatic ... more Publisher Summary This chapter explains how diet and post-ruminal nutrients influence pancreatic α-amylase expression and secretion in ruminants. Specific mechanisms involved in dietary regulation of α-amylase expression and secretion are also discussed. While the majority of starch consumed is fermented in the rumen, considerable quantities pass to the small intestine. The starch that passes to the small intestine is first hydrolyzed by pancreatic α-amylase. α-amylase provides the glycosidic activity secreted in pancreatic juice. The production and secretion of α-amylase is an important component regulating the digestive efficiency of starch in ruminants fed high-concentrate diets. Diet and post-ruminal nutrients do influence the expression and secretion of pancreatic α-amylase. At the cellular level, diet and post-ruminal nutrients appear to regulate expression of α-amylase at the translational level. Increases in the pancreatic protease and α-amylase activities are also observed when dietary protein or starch is replaced by a protein hydrolysate or glucose, respectively.
Bookmarks Related papers MentionsView impact
Journal of Animal Science
Sixty cows of varying frame scores (FS; 5.17 ± 1.38) were used to examine relationships between b... more Sixty cows of varying frame scores (FS; 5.17 ± 1.38) were used to examine relationships between body size [BW, FS, and body volume (V)] and cow efficiency. Dry matter intake (DMI) and BW change were monitored over 64 days starting 1 month before bull turnout. Cows were fed a forage-based diet and DMI monitored using the Insentec system. Average BW (ABW; 662 ± 93.3 kg) was calculated by averaging 2-d beginning and end BW. Measurements (body length, hip height, hip width, and heart, mid, and flank girth) were collected at the beginning and end of the experiment and average V (628 ± 96.4 L) calculated. Calf BW was recorded at weaning (WW). Pearson partial correlations between body size characteristics and efficiency measures were determined using GLM (SAS) and the MANOVA/PRINTE statement. There was positive correlation (P < 0.001; r = 0.84, 0.74, 0.81) between DMI (kg) and ABW, FS, and V. There was a tendency for negative correlation (P = 0.08, 0.09; r = -0.24, -0.23) between DMI (%...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
As cannabinoid production continues to increase, there is increasing interest in feeding byproduc... more As cannabinoid production continues to increase, there is increasing interest in feeding byproducts of industrial hemp production to livestock. An experiment using crossbred heifers (n = 31; initial BW= 494 kg, SE = 10) was conducted to determine the effects of feeding hempseed cake in a corn-based finishing diet (10% forage) formulated to meet or exceed ruminally degradable and metabolizable protein requirements on growth, performance, carcass characteristics, and feeding behavior. Heifers were assigned randomly to one of two treatments: 1.) diet containing 20% dried distillers grains plus solubles (CON, n = 16), or 2.) diet containing 20% hempseed cake (HEMP, n = 15) on a dry-matter basis. Cattle were housed in two pens, had ad-libitum access to feed and water, and individual intakes and feeding behavior were captured using the Insentec BV feeding system across the feeding period (111 d). Final BW was not different (P = 0.28) between CON (696 kg, SE = 12) and HEMP (683 kg, SE = 12...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To examine the effects of maternal nutrient restriction on net uteroplacental flux during mid-ges... more To examine the effects of maternal nutrient restriction on net uteroplacental flux during mid-gestation, 14 singleton ewes (48.2 ± 4.0 kg body weight) were fed 100% (control; CON; n = 7) or 60% of nutrient requirements (restricted; RES; n = 7) from day 50–90 (mid-gestation). On day 90, uteroplacental blood flow was measured via Doppler ultrasonography and blood samples were collected from the femoral artery, uterine vein, umbilical artery, and umbilical vein. Blood vessel glucose and amino acids (AA) concentrations were measured and arterial-venous (uterine, AV; fetal, va) differences and net fluxes were calculated. Data were analyzed using the GLM procedure of SAS for effects of treatment. Nutrient restriction during mid-gestation did not influence (P ≥ 0.17) uterine or umbilical blood flows. Uterine AV and fetal va differences of total, essential, and nonessential AA were not influenced (P > 0.10) by nutrient restriction. Nutrient restriction decreased (P ≤ 0.05) uterine and ut...
Bookmarks Related papers MentionsView impact
Reference Module in Food Science
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To determine the effects of maternal nutrient restriction and re-alimentation on offspring metabo... more To determine the effects of maternal nutrient restriction and re-alimentation on offspring metabolism, 48 pregnant ewes with singletons, were fed a control diet [100% National Research Council (NRC) requirements (CON)] starting at the beginning of gestation. On day 50 of gestation, ewes (n = 7) were euthanized and fetal liver, muscle, and blood samples were collected. The remaining animals were fed either CON or 60% NRC requirements (RES), a subset were euthanized at day 90 of gestation (n = 7/treatment), and fetal samples obtained. Remaining ewes were maintained on the current diet (CON-CON, n = 6; RES-RES, n = 7) or switched to alternative diet (CON-RES, RES-CON; n = 7/treatment). On day 130 of gestation, remaining ewes were euthanized, and fetal samples collected. Fetal liver, longissimus dorsi, and blood metabolites were analyzed using LC-MS/MS at Metabolon Inc. Pathway enrichment analysis was conducted using MetaboAnalyst 4.0. In liver, muscle, and blood, 64, 44, and 34 pathway...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
The objective of this experiment was to determine the influence of toxic endophyte-infected tall ... more The objective of this experiment was to determine the influence of toxic endophyte-infected tall fescue exposure on pancreatic and small intestinal digestive enzyme activities in steers. Twelve fescue-naive beef steers [693 ± 42.7 kg of body weight (BW)] were stratified by BW and randomly assigned within BW ranks to graze non-toxic endophyte-infected tall fescue (NTE, n = 6; 0.01 ± 0.009 mg ergovaline + ergovalinine/kg) or toxic endophyte-infected tall fescue (TE, n = 6; 0.50 ± 0.048 mg ergovaline + ergovalinine/kg) pastures for 84 d. After the grazing period, steers were weighed and then slaughtered in three groups for tissue collection. A 1-m segment of the small intestine was collected 5-m distal to the pyloric sphincter. Subsamples of the small intestinal mucosa and pancreas were collected, homogenized in saline, and assayed for protein concentration. Pancreatic and small intestinal digestive enzyme activities were assayed. Data were analyzed using the GLM procedure of SAS as a ...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
Nutrient requirements of grazing ruminants change throughout the production year. Also, pasture q... more Nutrient requirements of grazing ruminants change throughout the production year. Also, pasture quality and quantity change throughout the year and are influenced by environment. Therefore, there commonly are times of the year where nutrient requirements are not met from the forage alone. We have long known the importance of nutrition during key development including the conception, fetal, neonatal, and weaning period. Altering nutrition during these periods can have lasting effects on health and productivity. Much of the research in ruminants examining nutritional effects on development has focused on large changes in diet, such as energy or protein restriction, rather than specific nutrients such as amino acids. Amino acids play an important role to meet requirements for lean growth but also have other physiological functions regulating metabolism and health that have important effects on development. Amino acid deficiencies during the fetal and neonatal period(s) can result in sm...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
The neuropeptide receptor galanin receptor 2 (GALR2) is involved in appetite regulation and is th... more The neuropeptide receptor galanin receptor 2 (GALR2) is involved in appetite regulation and is therefore a potential target for marker-assisted management of finishing cattle. The objective of this study was to determine the interaction between implant strategy and GALR2 genotype on the metabolic status of feedlot steers. Angus crossbred steers (n = 93) were selected for the study based on GALR2 c.-199G >T genotype (n = 19 GG, 36 TT and 38 TG steers). Steers were blocked by initial body weight into two groups (248 ± 50 and 293± 43 kg) and finished for 166 or 202 days. Steers were assigned one of two implant strategies in a 2 (implant) × 3 (genotype) factorial design. The implant strategies were: one implant of Revalor-S (Merk, New Jersey) on day 77 of finishing (1X) or two implants with the first on day 0 and the second on day 77 (2X). All steers were fed a standard feedlot ration throughout the study. Blood samples were collected every 28 days. Serum samples were analyzed for bl...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
Leptin is a 16-kDa-peptide hormone product of the leptin gene (LEP) that is predominantly synthes... more Leptin is a 16-kDa-peptide hormone product of the leptin gene (LEP) that is predominantly synthesized by adipose tissues and has known involvement in regulation of feed intake, energy expenditure, reproduction, and immune functions. The objective was to determine the association of leptin genotype (LEP c.73C >T), leptin diplotype (LEPD) and plasma leptin hormone (LEPH) concentration with growth, feed intake, feed efficiency, and behavior characteristics in developing beef heifers. A total of 336 commercial beef heifers were genotyped for the LEP c.73C >T marker. Four single nucleotide polymorphism markers including LEP c.73C >T, ARS-BFGL-NGS-59298 (intron 1), BovineHD0400026029 (upstream) and BovineHD0400026063 (downstream) of LEP were considered for haplotype analysis. Eleven LEPD were identified for this study using parsimony-based analyses. Circulating levels of LEPH were measured on 333 heifers prior to their first breeding season and used to assign low or high concentr...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To determine the effects of maternal nutrient restriction and rumen-protected arginine supplement... more To determine the effects of maternal nutrient restriction and rumen-protected arginine supplementation on post-ruminal digestive enzymes in lambs, 31 multiparous, Rambouillet ewes were allocated to one of three dietary treatments at 54 d of gestation. Dietary treatments were 100% of nutrient requirements (control, CON; n=11), 60% of control (restricted, RES; n=10), or RES plus a rumen-protected arginine supplement dosed at 180 mg/kg BW once daily (RES-ARG; n=10). At parturition, lambs were immediately removed from dams and reared independently. Milk-replacer and alfalfa hay + creep feed was offered for ad libitum intake. At day 54 of age, lambs were slaughtered and the pancreas and small intestine were collected. Pancreatic (α-amylase, trypsin) and small intestinal (maltase, glucoamylase, sucrase, isomaltase, lactase) digestive enzyme activities were assayed. Data were analyzed using the GLM procedure of SAS with treatment and fetal sex included in the model statement. Contrast stat...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
The objective of this experiment was to examine the relationship between ambient temperature and ... more The objective of this experiment was to examine the relationship between ambient temperature and solar radiation with dry matter intake (DMI) in beef steers. Daily intake data from 790 beef steers collected from years 2011 to 2017 using an Insentec feeding system were used for this experiment. Data were condensed from daily data into weekly averages (n = 14250 steer-weeks). The variables considered for this experiment include DMI (2.50 to 23.60 kg/d), body weights (197.3 to 796.1 kg), energy density of diets (NEm; 0.7930 to 2.970 Mcal/kg), ambient temperature (-23.72 to 26.40 °C), two week lag of temperature, monthly lag of temperature, solar radiation (30.81 to 297.12 W/m2), two week lag of solar radiation and monthly lag of solar radiation. Residuals of DMI generated after fitting week of year as a fixed effect were used in scatter plots with explanatory variables to identify if non-linear relationships existed. Body weight and energy density were observed to have both linear and ...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
Twenty-four fall born Dorset-cross twin or triplet ram lambs were used to determine effects of su... more Twenty-four fall born Dorset-cross twin or triplet ram lambs were used to determine effects of supplemental leucine in milk replacer fed to neonatal lambs on pre- and post-weaning growth, organ weight, and carcass performance. Lambs were weighed after birth and allowed to nurse on dams for 12 h to allow for colostrum intake. At 12 h post-birth, lambs were assigned to one of two treatments: milk replacer (CON) and milk replacer with leucine added at 3% as-fed (LEU). Milk replacer treatments were offered for ad libitum intake for 42 d through a Lac-Tek milk machine. After 42 d, lambs were weaned and adapted to a finishing diet. Lambs were maintained on a finishing diet until one of two slaughter dates. Lamb weight through the pre- and post-weaning phases, organ weights, and carcass traits were determined. Data were analyzed using the GLM procedure of SAS. Leucine supplementation increased lamb ADG (P = 0.007) in the pre-weaning period. Leucine supplementation did not affect final body...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To determine the effects of maternal supplementation on the mRNA abundance of genes associated wi... more To determine the effects of maternal supplementation on the mRNA abundance of genes associated with metabolic function in fetal muscle and liver, pregnant sows (Landrace × Yorkshire; initial body weight (BW) 221.58 ± 33.26 kg; n = 21) fed a complete gestation diet (corn–soybean meal based diet, CSM) were randomly assigned to 1 of 4 isocaloric supplementation treatments: control (CON, 378 g/d CSM, n = 5), sucrose (SUGAR, 255 g/d crystalized sugar, n = 5), cooked ground beef (BEEF, 330 g/d n = 6), or BEEF + SUGAR (B+S, 165 g/d cooked ground beef and 129 g/d crystalized sugar, n = 5), from days 40 to 110 of gestation. Sows were euthanized on day 111 of gestation. Two male and 2 female fetuses of median BW were selected from each litter, and samples of the longissimus dorsi muscle and liver were collected. Relative transcript level was quantified via qPCR with HPRT1 as the reference gene for both muscle and liver samples. The following genes were selected and analyzed in the muscle: IGF...
Bookmarks Related papers MentionsView impact
Canadian Journal of Animal Science
Sixty-nine finishing steers were randomly assigned to one of two treatment groups: supplementatio... more Sixty-nine finishing steers were randomly assigned to one of two treatment groups: supplementation to provide 0 (CON) or 267 mg d-1 of ractopamine hydrochloride (RAC) for 42 d. Twelve steers were slaughtered for tissue and blood collection. Final body weight (BW) tended to be greater with RAC supplementation. Ractopamine hydrochloride supplementation decreased liver mass as a percentage of BW. Pancreatic protein concentration, digestive enzyme activities, serum glucose and insulin concentrations were not influenced by RAC supplementation. Ractopamine hydrochloride supplementation decreased the pancreatic: α-amylase:trypsin and serum urea-N concentrations. These data suggest that RAC may influence pancreatic exocrine function in cattle.
Bookmarks Related papers MentionsView impact
Canadian Journal of Animal Science, 2016
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To determine the effects of maternal nutrient restriction and re-alimentation on fetal liver and ... more To determine the effects of maternal nutrient restriction and re-alimentation on fetal liver and muscle development, 48 pregnant ewes with singletons, were fed a control diet [100% National Research Council (NRC) requirements (CON)] starting at the beginning of gestation. On day 50 of gestation, ewes (n = 7) were euthanized and fetal liver and skeletal muscle samples were collected. The remaining animals were fed either CON or 60% NRC requirements (RES), a subset were euthanized at day 90 of gestation (n = 7/treatment), and fetal samples obtained. Remaining ewes were maintained on the current diet (CON-CON, n = 6; RES-RES, n = 7) or switched to alternative diet (CON-RES, RES-CON; n = 7/treatment). On day 130 of gestation, remaining ewes were euthanized, and fetal samples collected. Fetal liver was analyzed for general tissue morphology, and fetal skeletal muscles were analyzed for lipid accumulation. mRNA expression of growth and metabolic factors were quantified in liver and muscle...
Bookmarks Related papers MentionsView impact
Biology of Growing Animals
Publisher Summary This chapter explains how diet and post-ruminal nutrients influence pancreatic ... more Publisher Summary This chapter explains how diet and post-ruminal nutrients influence pancreatic α-amylase expression and secretion in ruminants. Specific mechanisms involved in dietary regulation of α-amylase expression and secretion are also discussed. While the majority of starch consumed is fermented in the rumen, considerable quantities pass to the small intestine. The starch that passes to the small intestine is first hydrolyzed by pancreatic α-amylase. α-amylase provides the glycosidic activity secreted in pancreatic juice. The production and secretion of α-amylase is an important component regulating the digestive efficiency of starch in ruminants fed high-concentrate diets. Diet and post-ruminal nutrients do influence the expression and secretion of pancreatic α-amylase. At the cellular level, diet and post-ruminal nutrients appear to regulate expression of α-amylase at the translational level. Increases in the pancreatic protease and α-amylase activities are also observed when dietary protein or starch is replaced by a protein hydrolysate or glucose, respectively.
Bookmarks Related papers MentionsView impact
Journal of Animal Science
Sixty cows of varying frame scores (FS; 5.17 ± 1.38) were used to examine relationships between b... more Sixty cows of varying frame scores (FS; 5.17 ± 1.38) were used to examine relationships between body size [BW, FS, and body volume (V)] and cow efficiency. Dry matter intake (DMI) and BW change were monitored over 64 days starting 1 month before bull turnout. Cows were fed a forage-based diet and DMI monitored using the Insentec system. Average BW (ABW; 662 ± 93.3 kg) was calculated by averaging 2-d beginning and end BW. Measurements (body length, hip height, hip width, and heart, mid, and flank girth) were collected at the beginning and end of the experiment and average V (628 ± 96.4 L) calculated. Calf BW was recorded at weaning (WW). Pearson partial correlations between body size characteristics and efficiency measures were determined using GLM (SAS) and the MANOVA/PRINTE statement. There was positive correlation (P < 0.001; r = 0.84, 0.74, 0.81) between DMI (kg) and ABW, FS, and V. There was a tendency for negative correlation (P = 0.08, 0.09; r = -0.24, -0.23) between DMI (%...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
As cannabinoid production continues to increase, there is increasing interest in feeding byproduc... more As cannabinoid production continues to increase, there is increasing interest in feeding byproducts of industrial hemp production to livestock. An experiment using crossbred heifers (n = 31; initial BW= 494 kg, SE = 10) was conducted to determine the effects of feeding hempseed cake in a corn-based finishing diet (10% forage) formulated to meet or exceed ruminally degradable and metabolizable protein requirements on growth, performance, carcass characteristics, and feeding behavior. Heifers were assigned randomly to one of two treatments: 1.) diet containing 20% dried distillers grains plus solubles (CON, n = 16), or 2.) diet containing 20% hempseed cake (HEMP, n = 15) on a dry-matter basis. Cattle were housed in two pens, had ad-libitum access to feed and water, and individual intakes and feeding behavior were captured using the Insentec BV feeding system across the feeding period (111 d). Final BW was not different (P = 0.28) between CON (696 kg, SE = 12) and HEMP (683 kg, SE = 12...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To examine the effects of maternal nutrient restriction on net uteroplacental flux during mid-ges... more To examine the effects of maternal nutrient restriction on net uteroplacental flux during mid-gestation, 14 singleton ewes (48.2 ± 4.0 kg body weight) were fed 100% (control; CON; n = 7) or 60% of nutrient requirements (restricted; RES; n = 7) from day 50–90 (mid-gestation). On day 90, uteroplacental blood flow was measured via Doppler ultrasonography and blood samples were collected from the femoral artery, uterine vein, umbilical artery, and umbilical vein. Blood vessel glucose and amino acids (AA) concentrations were measured and arterial-venous (uterine, AV; fetal, va) differences and net fluxes were calculated. Data were analyzed using the GLM procedure of SAS for effects of treatment. Nutrient restriction during mid-gestation did not influence (P ≥ 0.17) uterine or umbilical blood flows. Uterine AV and fetal va differences of total, essential, and nonessential AA were not influenced (P > 0.10) by nutrient restriction. Nutrient restriction decreased (P ≤ 0.05) uterine and ut...
Bookmarks Related papers MentionsView impact
Reference Module in Food Science
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To determine the effects of maternal nutrient restriction and re-alimentation on offspring metabo... more To determine the effects of maternal nutrient restriction and re-alimentation on offspring metabolism, 48 pregnant ewes with singletons, were fed a control diet [100% National Research Council (NRC) requirements (CON)] starting at the beginning of gestation. On day 50 of gestation, ewes (n = 7) were euthanized and fetal liver, muscle, and blood samples were collected. The remaining animals were fed either CON or 60% NRC requirements (RES), a subset were euthanized at day 90 of gestation (n = 7/treatment), and fetal samples obtained. Remaining ewes were maintained on the current diet (CON-CON, n = 6; RES-RES, n = 7) or switched to alternative diet (CON-RES, RES-CON; n = 7/treatment). On day 130 of gestation, remaining ewes were euthanized, and fetal samples collected. Fetal liver, longissimus dorsi, and blood metabolites were analyzed using LC-MS/MS at Metabolon Inc. Pathway enrichment analysis was conducted using MetaboAnalyst 4.0. In liver, muscle, and blood, 64, 44, and 34 pathway...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
The objective of this experiment was to determine the influence of toxic endophyte-infected tall ... more The objective of this experiment was to determine the influence of toxic endophyte-infected tall fescue exposure on pancreatic and small intestinal digestive enzyme activities in steers. Twelve fescue-naive beef steers [693 ± 42.7 kg of body weight (BW)] were stratified by BW and randomly assigned within BW ranks to graze non-toxic endophyte-infected tall fescue (NTE, n = 6; 0.01 ± 0.009 mg ergovaline + ergovalinine/kg) or toxic endophyte-infected tall fescue (TE, n = 6; 0.50 ± 0.048 mg ergovaline + ergovalinine/kg) pastures for 84 d. After the grazing period, steers were weighed and then slaughtered in three groups for tissue collection. A 1-m segment of the small intestine was collected 5-m distal to the pyloric sphincter. Subsamples of the small intestinal mucosa and pancreas were collected, homogenized in saline, and assayed for protein concentration. Pancreatic and small intestinal digestive enzyme activities were assayed. Data were analyzed using the GLM procedure of SAS as a ...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
Nutrient requirements of grazing ruminants change throughout the production year. Also, pasture q... more Nutrient requirements of grazing ruminants change throughout the production year. Also, pasture quality and quantity change throughout the year and are influenced by environment. Therefore, there commonly are times of the year where nutrient requirements are not met from the forage alone. We have long known the importance of nutrition during key development including the conception, fetal, neonatal, and weaning period. Altering nutrition during these periods can have lasting effects on health and productivity. Much of the research in ruminants examining nutritional effects on development has focused on large changes in diet, such as energy or protein restriction, rather than specific nutrients such as amino acids. Amino acids play an important role to meet requirements for lean growth but also have other physiological functions regulating metabolism and health that have important effects on development. Amino acid deficiencies during the fetal and neonatal period(s) can result in sm...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
The neuropeptide receptor galanin receptor 2 (GALR2) is involved in appetite regulation and is th... more The neuropeptide receptor galanin receptor 2 (GALR2) is involved in appetite regulation and is therefore a potential target for marker-assisted management of finishing cattle. The objective of this study was to determine the interaction between implant strategy and GALR2 genotype on the metabolic status of feedlot steers. Angus crossbred steers (n = 93) were selected for the study based on GALR2 c.-199G >T genotype (n = 19 GG, 36 TT and 38 TG steers). Steers were blocked by initial body weight into two groups (248 ± 50 and 293± 43 kg) and finished for 166 or 202 days. Steers were assigned one of two implant strategies in a 2 (implant) × 3 (genotype) factorial design. The implant strategies were: one implant of Revalor-S (Merk, New Jersey) on day 77 of finishing (1X) or two implants with the first on day 0 and the second on day 77 (2X). All steers were fed a standard feedlot ration throughout the study. Blood samples were collected every 28 days. Serum samples were analyzed for bl...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
Leptin is a 16-kDa-peptide hormone product of the leptin gene (LEP) that is predominantly synthes... more Leptin is a 16-kDa-peptide hormone product of the leptin gene (LEP) that is predominantly synthesized by adipose tissues and has known involvement in regulation of feed intake, energy expenditure, reproduction, and immune functions. The objective was to determine the association of leptin genotype (LEP c.73C >T), leptin diplotype (LEPD) and plasma leptin hormone (LEPH) concentration with growth, feed intake, feed efficiency, and behavior characteristics in developing beef heifers. A total of 336 commercial beef heifers were genotyped for the LEP c.73C >T marker. Four single nucleotide polymorphism markers including LEP c.73C >T, ARS-BFGL-NGS-59298 (intron 1), BovineHD0400026029 (upstream) and BovineHD0400026063 (downstream) of LEP were considered for haplotype analysis. Eleven LEPD were identified for this study using parsimony-based analyses. Circulating levels of LEPH were measured on 333 heifers prior to their first breeding season and used to assign low or high concentr...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To determine the effects of maternal nutrient restriction and rumen-protected arginine supplement... more To determine the effects of maternal nutrient restriction and rumen-protected arginine supplementation on post-ruminal digestive enzymes in lambs, 31 multiparous, Rambouillet ewes were allocated to one of three dietary treatments at 54 d of gestation. Dietary treatments were 100% of nutrient requirements (control, CON; n=11), 60% of control (restricted, RES; n=10), or RES plus a rumen-protected arginine supplement dosed at 180 mg/kg BW once daily (RES-ARG; n=10). At parturition, lambs were immediately removed from dams and reared independently. Milk-replacer and alfalfa hay + creep feed was offered for ad libitum intake. At day 54 of age, lambs were slaughtered and the pancreas and small intestine were collected. Pancreatic (α-amylase, trypsin) and small intestinal (maltase, glucoamylase, sucrase, isomaltase, lactase) digestive enzyme activities were assayed. Data were analyzed using the GLM procedure of SAS with treatment and fetal sex included in the model statement. Contrast stat...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
The objective of this experiment was to examine the relationship between ambient temperature and ... more The objective of this experiment was to examine the relationship between ambient temperature and solar radiation with dry matter intake (DMI) in beef steers. Daily intake data from 790 beef steers collected from years 2011 to 2017 using an Insentec feeding system were used for this experiment. Data were condensed from daily data into weekly averages (n = 14250 steer-weeks). The variables considered for this experiment include DMI (2.50 to 23.60 kg/d), body weights (197.3 to 796.1 kg), energy density of diets (NEm; 0.7930 to 2.970 Mcal/kg), ambient temperature (-23.72 to 26.40 °C), two week lag of temperature, monthly lag of temperature, solar radiation (30.81 to 297.12 W/m2), two week lag of solar radiation and monthly lag of solar radiation. Residuals of DMI generated after fitting week of year as a fixed effect were used in scatter plots with explanatory variables to identify if non-linear relationships existed. Body weight and energy density were observed to have both linear and ...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
Twenty-four fall born Dorset-cross twin or triplet ram lambs were used to determine effects of su... more Twenty-four fall born Dorset-cross twin or triplet ram lambs were used to determine effects of supplemental leucine in milk replacer fed to neonatal lambs on pre- and post-weaning growth, organ weight, and carcass performance. Lambs were weighed after birth and allowed to nurse on dams for 12 h to allow for colostrum intake. At 12 h post-birth, lambs were assigned to one of two treatments: milk replacer (CON) and milk replacer with leucine added at 3% as-fed (LEU). Milk replacer treatments were offered for ad libitum intake for 42 d through a Lac-Tek milk machine. After 42 d, lambs were weaned and adapted to a finishing diet. Lambs were maintained on a finishing diet until one of two slaughter dates. Lamb weight through the pre- and post-weaning phases, organ weights, and carcass traits were determined. Data were analyzed using the GLM procedure of SAS. Leucine supplementation increased lamb ADG (P = 0.007) in the pre-weaning period. Leucine supplementation did not affect final body...
Bookmarks Related papers MentionsView impact
Journal of Animal Science
To determine the effects of maternal supplementation on the mRNA abundance of genes associated wi... more To determine the effects of maternal supplementation on the mRNA abundance of genes associated with metabolic function in fetal muscle and liver, pregnant sows (Landrace × Yorkshire; initial body weight (BW) 221.58 ± 33.26 kg; n = 21) fed a complete gestation diet (corn–soybean meal based diet, CSM) were randomly assigned to 1 of 4 isocaloric supplementation treatments: control (CON, 378 g/d CSM, n = 5), sucrose (SUGAR, 255 g/d crystalized sugar, n = 5), cooked ground beef (BEEF, 330 g/d n = 6), or BEEF + SUGAR (B+S, 165 g/d cooked ground beef and 129 g/d crystalized sugar, n = 5), from days 40 to 110 of gestation. Sows were euthanized on day 111 of gestation. Two male and 2 female fetuses of median BW were selected from each litter, and samples of the longissimus dorsi muscle and liver were collected. Relative transcript level was quantified via qPCR with HPRT1 as the reference gene for both muscle and liver samples. The following genes were selected and analyzed in the muscle: IGF...
Bookmarks Related papers MentionsView impact
Canadian Journal of Animal Science
Sixty-nine finishing steers were randomly assigned to one of two treatment groups: supplementatio... more Sixty-nine finishing steers were randomly assigned to one of two treatment groups: supplementation to provide 0 (CON) or 267 mg d-1 of ractopamine hydrochloride (RAC) for 42 d. Twelve steers were slaughtered for tissue and blood collection. Final body weight (BW) tended to be greater with RAC supplementation. Ractopamine hydrochloride supplementation decreased liver mass as a percentage of BW. Pancreatic protein concentration, digestive enzyme activities, serum glucose and insulin concentrations were not influenced by RAC supplementation. Ractopamine hydrochloride supplementation decreased the pancreatic: α-amylase:trypsin and serum urea-N concentrations. These data suggest that RAC may influence pancreatic exocrine function in cattle.
Bookmarks Related papers MentionsView impact