Diet Of Calves Research Articles

Diet Influences Early Microbiota Development in Dairy Calves without Long-Term Impacts on Milk Production.

Gastrointestinal tract (GIT) microorganisms play important roles in the health of ruminant livestock and affect the production of agriculturally relevant products, including milk and meat. Despite this link, interventions to alter the adult microbiota to improve production have proven ineffective, as established microbial communities are resilient to change. In contrast, developing communities in young animals may be more easily altered but are less well studied. Here, we measured the GIT-associated microbiota of 45 Holstein dairy cows from 2 weeks to the first lactation cycle, using Illumina amplicon sequencing of bacterial (16S rRNA V4), archaeal (16S rRNA V6 to V8), and fungal (internal transcribed region 1 [ITS1]) communities. Fecal and ruminal microbiota of cows raised on calf starter grains and/or corn silage were correlated to lifetime growth as well as milk production during the first lactation cycle, in order to determine whether early-life diets have long-term impacts. Significant diet-associated differences in total microbial communities and specific taxa were observed by weaning (8 weeks), but all animals reached an adult-like composition between weaning and 1 year. While some calf-diet-driven differences were apparent in the microbiota of adult cows, these dissimilarities did not correlate with animal growth or milk production. This finding suggests that initial microbial community establishment is affected by early-life diet but postweaning factors have a greater influence on adult communities and production outcomes.IMPORTANCE The gut microbiota is essential for the survival of many organisms, including ruminants that rely on microorganisms for nutrient acquisition from dietary inputs for the production of products such as milk and meat. While alteration of the adult ruminant microbiota to improve production is possible, changes are often unstable and fail to persist. In contrast, the early-life microbiota may be more amenable to sustained modification. However, few studies have determined the impact of early-life interventions on downstream production. Here, we investigated the impact of agriculturally relevant calf diets, including calf starter and corn silage, on gut microbial communities, growth, and production through the first lactation cycle. Thus, this work serves to further our understanding of early-life microbiota acquisition, as well as informing future practices in livestock management.

Reciprocal combinations of alfalfa hay and corn silage in the starter diets of Holstein dairy calves: effects on growth performance, nutrient digestibility, rumen fermentation and selected blood metabolites

Adding corn silage (CS) instead of alfalfa hay (AH) to the finely ground starter diet would improve calf performance if feed intake or feed efficiency is increased. We investigated the effects of replacing AH with CS in the starter diet on nutrient intake, digestibility, growth performance, rumen fermentation and selected blood metabolites in Holstein calves. Newborn male calves (n = 30; 3 days of age; 40.2 ± 1.28 kg BW) were assigned randomly to three groups receiving starter diets containing chopped AH (10% dry matter (DM) basis; AH diet), CS (10% DM, CS diet) or their combination (each at 5% level; AHCS diet). The starter diets had the same nutrient composition but differed in DM content (91.2%, 87.5% and 83.8% for AH, AHCS and CS, respectively). The calves were weaned on day 50, and the study continued until day 70. Nutrient intake, BW (at weaning and at the end of the study) and body measurements were not affected by the diet. During the post-weaning period, average daily gain tended to be greater on CS than on AH diet. Feed efficiency was greater in CS than in AH or AHCS calves during the post-weaning period. Digestibility of neutral detergent fiber was greater in AHCS and CS compared with AH during the post-weaning period. Concentration and profile of volatile fatty acids and ruminal fluid pH were not affected by the diet. Replacing AH with CS in the starter diet had no effect on feed intake, growth performance and general health of the calves. These results indicate that AH and CS can be used interchangeably in dairy calf starter diets until 70 days of age, allowing dairy producers more choices in selecting the feed ingredients.

Optimization of Vitamin a Nutrition of Calves Fattened on Wastes of Food Industry

The most important sources of fodder resources are wastes of food industry: pulp, distiller's grains, brewer's grains, malt sprouts, etc., which are widely used for cattle fattening.The research was aimed at determining the optimal dosages of vitamin A in the diet of calves fattened on pulp, distiller's grains, brewer's grains, and malt sprouts.

Effects of folic acid on growth performance, ruminal fermentation, nutrient digestibility and urinary excretion of purine derivatives in post-weaned dairy calves

ABSTRACTThis study evaluated the effects of folic acid (FA) supplementation on growth performance, ruminal fermentation, nutrient digestibility and urinary purine derivatives (PD) excretion in dairy calves. Forty-eight Chinese Holstein male dairy calves at 60 ± 3.2 d of age and 89 ± 5.9 kg body weight (mean ± standard error) were assigned to one of four groups in a randomised block design. Calves in control group were fed basal diet, calves in low FA, medium FA and high FA groups with 3.6, 7.2 and 10.8 mg FA per kg basal diet, respectively. The dietary corn silage to concentrate ratio was 50:50 (dry matter [DM] basis). DM intake and average daily gain (ADG) quadratically increased, and feed conversion ratio quadratically decreased with increasing FA supplementation. Ruminal pH linearly decreased, whereas total volatile fatty acids quadratically increased. The unchanged acetate-to-propionate ratio was due to the similar change in acetate and propionate concentration. Ammonia N content quadratically decreased. Digestibility of DM, organic matter, crude protein, ether extract, neutral detergent fibre and acid detergent fibre linearly increased. Activities of carboxymethyl cellulase, cellobiase, xylanase and pectinase linearly increased, but α-amylase and protease quadratically increased. Abundance of Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes linearly increased, but Butyrivibrio fibrisolvens and Prevotella ruminicola quadratically increased. Urinary total PD excretion quadratically increased. The results indicated that FA supplementation increased ADG, ruminal fermentation and nutrient digestibility with promoted ruminal microbial growth and enzyme activity, and the optimum dose was 7.2 mg FA per kg basal diet for calves.

Effect of a butyrate-fortified milk replacer on gastrointestinal microbiota and products of fermentation in artificially reared dairy calves at weaning

Enrichment of calf diets with exogenous butyrate has shown promise as a promotor of calf growth and intestinal development. However, the impact of dietary derived butyrate on the gut microbiota and their potential role, in turn, as mediators of its effect on calf growth and development is not known. Here, the effects of butyrate supplementation on rumen and hindgut microbiota and fermentation profiles were assessed in 16 Holstein-Friesian bull calves randomly assigned to one of two groups: Control (CON) fed conventional milk replacer or Sodium-Butyrate (SB – added to milk replacer) from days 7 to 56 of life. In the colon, total short chain fatty acid (SCFA), propionate and acetate concentrations were increased by SB (P < 0.05). 16S rRNA gene amplicon sequencing showed cecal abundance of butyrate producers Butyrivibrio and Shuttleworthia were decreased by SB (P < 0.05), while that of the propionate producer Phascolarctobacterium was higher (P < 0.05). Mogibacterium is associated with impaired gut health and was reduced in the cecum of SB calves (P < 0.05). These data show that the beneficial effects of SB on growth and performance occur in tandem with changes in the abundance of important SCFA producing and health-associated bacteria in the hindgut in milk-fed calves.

Direct-fed microbial supplementation influences the bacteria community composition of the gastrointestinal tract of pre- and post-weaned calves

This study investigated the effect of supplementing the diet of calves with two direct fed microbials (DFMs) (Saccharomyces cerevisiae boulardii CNCM I-1079 (SCB) and Lactobacillus acidophilus BT1386 (LA)), and an antibiotic growth promoter (ATB). Thirty-two dairy calves were fed a control diet (CTL) supplemented with SCB or LA or ATB for 96 days. On day 33 (pre-weaning, n = 16) and day 96 (post-weaning, n = 16), digesta from the rumen, ileum, and colon, and mucosa from the ileum and colon were collected. The bacterial diversity and composition of the gastrointestinal tract (GIT) of pre- and post-weaned calves were characterized by sequencing the V3-V4 region of the bacterial 16S rRNA gene. The DFMs had significant impact on bacteria community structure with most changes associated with treatment occurring in the pre-weaning period and mostly in the ileum but less impact on bacteria diversity. Both SCB and LA significantly reduced the potential pathogenic bacteria genera, Streptococcus and Tyzzerella_4 (FDR ≤ 8.49E-06) and increased the beneficial bacteria, Fibrobacter (FDR ≤ 5.55E-04) compared to control. Other potential beneficial bacteria, including Rumminococcaceae UCG 005, Roseburia and Olsenella, were only increased (FDR ≤ 1.30E-02) by SCB treatment compared to control. Furthermore, the pathogenic bacterium, Peptoclostridium, was reduced (FDR = 1.58E-02) by SCB only while LA reduced (FDR = 1.74E-05) Ruminococcus_2. Functional prediction analysis suggested that both DFMs impacted (p < 0.05) pathways such as cell cycle, bile secretion, proteasome, cAMP signaling pathway, thyroid hormone synthesis pathway and dopaminergic synapse pathway. Compared to the DFMs, ATB had similar impact on bacterial diversity in all GIT sites but greater impact on the bacterial composition of the ileum. Overall, this study provides an insight on the bacteria genera impacted by DFMs and the potential mechanisms by which DFMs affect the GIT microbiota and may therefore facilitate development of DFMs as alternatives to ATB use in dairy calf management.

Relationships between starch concentration of dry feed, diet digestibility, and growth of dairy calves up to 16 weeks of age

Our objective was to examine the potential relationship between starch concentration of dry feed and growth performance of young dairy calves via mixed-effects model analyses. A database was developed from 6 published studies conducted at the Nurture Research Center, Provimi (Brookville, OH), from 2008 to 2017 that included 18 dietary treatments and 372 calves at 0 to 8 wk of age in 5 nursery trials and 26 dietary treatments and 660 calves at 8 to 16 wk of age in 8 grower trials. The dry feeds ranged from 10.1 to 53.3% starch, 12.1 to 45.3% neutral detergent fiber, and 2.7 to 3.0 Mcal/kg of metabolizable energy [dry matter (DM) basis]. In all nursery trials, with increasing starch concentration in starter, average daily gain (ADG), hip width change, and starter intake linearly increased. In all grower trials, as starch concentration of dry feed increased, ADG, hip width change, and ADG/DM intake linearly increased; DM intake and DM intake/body weight were unaffected. In addition, the calves at 6 to 16 wk of age had greater digestibility of DM and crude protein with increasing starch concentration of dry feed. As indicated by meta-regression analysis, growth responses to starch concentration were influenced by metabolizable energy concentration in dry feed fed to the calves up to 16 wk of age. Changing starch from 23 to 43% on a DM basis (a typical range in the US industry) was predicted to increase ADG and hip width change by 5.8 and 5.0%, respectively, for calves at 0 to 8 wk of age and by 9.6 and 11.2%, respectively, for calves at 8 to 16 wk of age. Positive linear relationships between starch concentration of dry feed with DM digestibility, ADG, and hip width change reflect the importance of starch in the diets of young dairy calves.

Calcium propionate supplementation improves development of rumen epithelium in calves via stimulating G protein-coupled receptors

In the present study, calcium propionate (CaP) was used as feed additive in the diet of calves to investigate their effects on rumen fermentation and the development of rumen epithelium in calves. To elucidate the mechanism in which CaP improves development of calf rumen epithelium via stimulating the messenger RNA (mRNA) expression of G protein-coupled receptors, a total of 54 male Jersey calves (age=7±1 days, BW=23.1±1.2 kg) were randomly divided into three treatment groups: control without CaP supplementation (Con), 5% CaP supplementation (5% CaP) and 10% CaP supplementation (10% CaP). The experiment lasted 160 days and was divided into three feeding stages: Stage 1 (days 0 to 30), Stage 2 (days 31 to 90) and Stage 3 (days 91 to 160). Calcium propionate supplementation percentages were calculated on a dry matter basis. In total, six calves from each group were randomly selected and slaughtered on days 30, 90 and 160 at the conclusion of each experimental feeding stage. Rumen fermentation was improved with increasing concentration of CaP supplementation in calves through the first 30 days (Stage 1). No effects of CaP supplementation were observed on rumen fermentation in calves during Stage 2 (days 31 to 90). Supplementation with 5% CaP increased propionate concentration, but not acetate and butyrate in calves during Stage 3 (days 91 to 160). The rumen papillae length of calves in the 5% CaP supplementation group was greater than that of Con groups in calves after 160 days feeding. The mRNA expression of G protein-coupled receptor 41 (GPR41) and GPR43 supplemented with 5% CaP were greater than the control group and 10% CaP group in feeding 160 days calves. 5% CaP supplementation increased the mRNA expression of cyclin D1, whereas did not increase the mRNA expression of cyclin-dependent kinase 4 compared with the control group in feeding 160-day calves. These results indicate that propionate may act as a signaling molecule to improve rumen epithelium development through stimulating mRNA expression of GPR41 and GPR43.

Safety evaluation of dietary levels of 25-hydroxyvitamin D3 in growing calves

The objective of this study was to evaluate the safety of 25-OH-D3 addition to the diet of bovine calves. The investigation was conducted as a feeding experiment for 90 days. 40 calves were allotted to four groups: T1 - control group which received 30 IU vitamin D3/kg feed, and three experimental groups, which received 25-OH-D3 in increasing dosages: T2 - 25-OH-D3 at 1.7 μg/kg, T3 - 25-OH-D3 at 5.1 μg/kg and T4 - 25-OH-D3 at 8.5 μg/kg. All calves in the four groups gained weight continually: no growth depression was observed. No adverse effects of 25- OH-D3 were observed for any of the hematology and serum chemistry parameters measured or during the routine clinical examinations. Plasma 25-OH-D3 concentration was higher (p<0.05) in groups T2, T3 and T4 compared to that observed in group T1. Tissues content of 25-OH-D3 was significantly higher in in groups T2, T3 and T4 than in group T1. In the post-mortem evaluation, no adverse effects of the different 25-OH-D3 doses were observed, neither during the gross pathology nor in the histological examination. The results of this study show explicitly that there were no adverse effects of 25-OH-D3 compared to the control group, supplemented with vitamin D3.

A 100-Year Review: Calf nutrition and management

The first calf paper, published in the May 1919 issue of the Journal of Dairy Science (JDS), described factors affecting birth body weight of different breeds of calves. Other studies were done on nonmilk ingredients, growth charts were developed, and early weaning was followed to conserve milk fed to calves. Calf papers did not report use of statistics to control or record variation or to determine whether treatment means were different. Many experiments were more observational than comparative. Typically fewer than 5 calves, and sometimes 1 or 2 calves, were used per treatment. During the next 20 yr, calf studies increased and included colostrum feeding, milk and milk replacer feeding, minerals and vitamins, and fats and oils. Many concepts fundamental to current knowledge and understanding of digestion, rumen development, and milk replacer formulation were developed during this period. In addition, the concept of using antibiotic growth promoters in dairy calf diets was first evaluated and developed during the 1950s. During the 20-yr period of January 1957 through December 1976, a large number of universities in the United States and 1 in Canada contributed almost 150 papers on a variety of calf-related topics. These topics included genetics, physiology of the calf, review of calf immunity, antibiotic feeding, and milk replacer ingredients. This became the golden era of calf rumen development studies, which also engendered studies of calf starter rations and ingredients. A classic review of management, feeding, and housing studies summarized research related to calf feeding and management systems up to that point with an emphasis on maintaining calf growth and health while reducing labor and feed costs. It was also during this period that metric measurements replaced English units. In the 20-yr period from 1977 to 1996, more than 400 articles on calf nutrition and management were published in JDS. With the growing research interest in calves, a paper outlining standardized procedures for conducting and reporting data from calf experiments was first published. A very active area of calf nutrition research from the late 1970s to the mid 1980s was colostrum quality, feeding, and preservation; more than 60 such research articles were published in the journal during this time. Various nonmilk protein sources were evaluated. Extensive studies were done evaluating trace and major mineral requirements in calves along with some vitamin studies. Throughout the 1970s, 1980s, and 1990s, the primary objective of most calf research was how to wean healthy, adequately grown calves at an early age-generally less than 30 d of age. This program was reviewed in a 1979 publication. Research on calf starter ingredients, nutrient composition, and additives was minimal in the 1980s and 1990s given the importance of starter intake to the success of early weaning, but the role of water intake in starter intake and growth was established. Research on issues with calves continued to increase during the last 20-yr period as evidenced by publication of more than 580 articles in JDS as well as many more in other refereed journals. In addition to papers contributed by several universities in the United States and Canada, the number of papers authored by scientists at universities and institutes in other countries increased dramatically during this period. Factors influencing colostral antibody absorption, heat treatment of colostrum, and efficacy of colostrum supplements and replacers were reported. Most studies in this period related to nutrition. Studies were published supporting greater neonatal growth rates from feeding more milk replacer but with a higher crude protein content than traditional. Protein energy effects on growth and body composition were evaluated in concert with greater growth rates. Milk and nonmilk protein sources in milk replacers along with AA supplementation were evaluated. Limited studies were done with fat sources and fatty acid supplementation along with trace minerals and fat-soluble vitamins. Waste milk feeding and heat treatment became more prevalent. Studies established starter ingredient palatability and use of forage when fed with pelleted starters. With the advent of automatic milk and milk replacer feeders, factors influencing how and when to wean were established. Research programs established factors affecting calf behavior and welfare. Several databases were evaluated along with various published studies, and established calf growth during the first 2 mo was subsequently reflected in first- and later-lactation milk production of those calves. A new area of calf research that emerged from 1997 on was the effects of maternal environment and nutrition on calf health, growth, and future productivity. From a mechanistic standpoint, the field of epigenetics seems likely to explain many of these phenomena. Some possibilities for future calf nutrition and management were elaborated.

Effects of protein and fat concentration in coproduct-based growing calf diets on adipogenic and lipogenic gene expression, blood metabolites, and carcass composition.

Crossbred calves ( = 30; age = 95 ± 1.7 d; BW = 179 ± 18 kg) were fed 1 of 5 growing diets: 1) corn-based control, 2) low-fat, low-protein coproduct blend, 3) high-fat, low-protein coproduct blend, 4) low-fat, high-protein coproduct blend, and 5) high-fat, high-protein coproduct blend for 112 d (growing phase) followed by a common corn-based finishing diet (additional 112 d; finishing phase). Calves were biopsied at 0, 112, and 224 d for transcriptional analysis via real-time quantitative PCR of 14 genes associated with adipogenesis and lipogenesis within the muscle. Serum was collected at d 0, 112, and 224 and analyzed for leptin, IGF-1, and GH concentration. Treatments were arranged in a 2 × 2 factorial. Data were analyzed using the MIXED procedures of SAS (SAS Inst. Inc., Cary, NC) to ascertain the effects of 2 protein levels, 2 fat levels, time, and any interactions. Increased protein and decreased fat in the growing diet resulted in a carryover effect that increased ( 0.01) gene expression of PPARγ, insulin-induced gene 1, thyroid hormone responsive SPOT14 protein, ATP citrate lyase, adiponectin, diacylglycerol O-acyltransferase homologue 2, fatty acid binding protein 4, fatty acid synthase, phosphoenolpyruvate carboxykinase 1, and stearoyl-CoA desaturase as well as serum leptin concentrations between d 112 and 224. Expression of sterol regulatory element binding transcription factor 1 was increased ( 0.01) at d 112 in steers fed high-protein, high-fat diets compared to those fed high-protein, low-fat diets. A fat × day interaction ( 0.01) occurred for the expression of adiponectin receptor 2 and CCAAT/enhancer binding protein alpha, resulting in a carryover effect wherein low-fat diets fed during the growing phase increased expression of both genes at the end of the finishing phase (d 224). After slaughter, cattle fed the control during the growing phase tended ( 0.09) to have greater marbling scores, whereas other carcass parameters were not different ( ≥ 0.13). These data indicate that feeding differing levels of dietary fat and protein during the growing phase does affect i.m. adipogenesis at the transcriptional level, but differences in gene expression were not sufficient to affect carcass quality among cattle fed coproducts.

Effect of different fat supplements on performance of dairy calves during cold season

The objective of this experiment was to evaluate the effects of starter supplementation with fat sources differing in their fatty acid (FA) profile on performance of dairy calves during cold season. Sixty Holstein calves (3 d of age; 39.7 ± 3.8 kg of body weight) were randomly assigned to 1 of 5 starter diets supplemented with (1) no fat or oil source (control), (2) 3% palm fat (PLF), (3) 3% soybean oil (SBO), (4) 3% tallow (TAL), and (5) a 3.2% mixture (MIX) of PLF, SBO, and fish oil. The fat supplements were substituted for corn in the basal starter diet. Both the control and fat-supplemented diets contained similar amounts of dietary crude protein (19.4%), but the latter had a slightly higher quantity of calculated metabolizable energy (3.17 vs. 3.07 Mcal/kg) than did the former. Calves were reared outdoor in individual pens during the cold of winter with a mean ambient temperature of 5.0°C during the study period. Whole milk was offered twice daily from d 3 to 45 and once from d 46 to 49. The animals were weaned on d 50 and monitored in their individual pens until d 70. Supplementation with SBO and MIX increased both the dietary concentration and ratio of essential FA (n-6 and n-3), whereas supplementation with TAL and PLF made no change in the essential FA profile. Starter intake and average daily gain were not affected by PLF and TAL supplements, but were reduced as a result of feeding MIX. Feeding supplemental SBO did not affect starter intake, but tended to improve average daily gain and final body weight. Fat sources had no effects on body skeletal measurements, fecal score, digestibility, ruminal pH, ammonia, and total volatile FA concentrations; however, feeding MIX increased rumen molar proportion of propionate. No differences were observed in blood metabolites across the treatments during the preweaning period. Plasma concentrations of triacylglycerol and cholesterol increased when fat sources were supplemented and glucose concentration increased when SBO was supplemented during the postweaning period. Overall, addition of 3% PLF or TAL to the diet of young calves failed to improve growth performance. Although addition of SBO and MIX increased the dietary essential FA concentration, calf performance was only improved when SBO was supplemented.

Effects of a blended garlic and cinnamon essential oil extract with and without monensin sodium on the performance of grazing steers

ABSTRACT A series of stocker grazing experiments was conducted with the objective to determine the efficacy of supplementing growing calf diets with essential oils from garlic and cinnamon extracts (GCOE) in promoting growth on cool-season annual grasses in Arkansas (SWREC) and Oklahoma (SPER), or native rangeland at SPER. At the SWREC, steers (n = 272, BW ± SE = 209 ± 7.8 kg) grazing cool-season annual pastures were hand fed supplements containing mineral premixes that (1) were nonmedicated, (2) provided 250 mg/d of GCOE (NextEnhance, Novus International, St. Louis, MO), (3) provided 200 mg/d of monensin (MON, Rumensin, Elanco Animal Health, Indianapolis, IN), or (4) provided both 250 mg/d of GCOE and 200 mg/d of MON. In the SWREC experiment, there were no differences (P ≥ 0.13) in either BW or ADG due to GCOE, MON, or their interactions. At the SPER, steers grazing wheat pasture (n = 72, BW ± SE = 250 ± 3.9 kg) were offered ad libitum access to mineral supplements that were nonmedicated or contained 1.6 g of GCOE/kg mineral, and steers and heifers (n = 132, BW ± SE = 249 ± 4.7 kg) grazing summer native rangeland were offered ad libitum access to mineral supplements that (1) were nonmedicated; (2) provided 2.4 g of GCOE/kg; (3) provided 1.8 g of MON/kg, or (4) provided 1.8 g of MON and 2.4 g of GCOE/kg. At the SPER, there were no differences (P ≥ 0.12) in either BW or ADG due to GCOE, MON, or their interactions. In these experiments, providing GCOE or MON either by hand feeding or in self-fed mineral supplements had no effect (P ≥ 0.12) on ADG or BW of growing calves grazing cool-season annual grass pasture or summer native rangeland.

Influence of dairy by-product waste milk on the microbiomes of different gastrointestinal tract components in pre-weaned dairy calves

The community structure of colonised bacteria in the gastrointestinal tracts (GITs) of pre-weaned calves is affected by extrinsic factors, such as the genetics and diet of the calves; however, the dietary impact is not fully understood and warrants further research. Our study revealed that a total of 6, 5, 2 and 10 bacterial genera showed biologically significant differences in the GITs of pre-weaned calves fed four waste-milk diets: acidified waste milk, pasteurised waste milk, untreated bulk milk, and untreated waste milk, respectively. Specifically, generic biomarkers were observed in the rumen (e.g., Bifidobacterium, Parabacteroides, Fibrobacter, Clostridium, etc.), caecum (e.g., Faecalibacterium, Oxalobacter, Odoribacter, etc.) and colon (e.g., Megamonas, Comamonas, Stenotrophomonas, etc.) but not in the faeces. In addition, the predicted metabolic pathways showed that the expression of genes related to metabolic diseases was increased in the calves fed untreated waste milk, which indicated that untreated waste milk is not a suitable liquid diet for pre-weaned calves. This is the first study to demonstrate how different types of waste milk fed to pre-weaned calves affect the community structure of colonised bacteria, and the results may provide insights for the intentional adjustment of diets and gastrointestinal bacterial communities.

Effects of Feeding Calcium Hydroxide Treated Corn Stover During Backgrounding on Beef Carcass and Quality Characteristics

ObjectivesSixty-seven purebred Angus steers (initial BW 197 ± 38 kg.) were used to evaluate the effects of calcium hydroxide treated corn stover in backgrounding diets and a common finishing phase.Materials and MethodsSteers were randomly assigned to 1 of 4 treatments: untreated corn stover (CON), corn stover treated with 50% DM water (H2O); 50% DM water and calcium hydroxide treated corn stover (CaOH2); grazing on a turnip cover crop (CC) for 29 d before adapted to ad libitum alfalfa haylage diet fed in feed bunks for remaining 20 d of backgrounding. Steers were fed individually using a Calan system. All diets were formulated on a dry matter (DM) basis to contain 30% corn stover, 15% alfalfa haylage, 25% dried distillers grains with solubles, 25% dry rolled corn, and 5% supplement containing monensin. Steers were harvested at 240 d on feed. Carcass characteristics were recorded 48 h postmortem. Strip loins and shoulder clods (IMPS #180 and #114) from the right side of the carcass were collected. The shoulder clods were frozen immediately on arrival to the meat lab. Strip loins were fabricated into 2.54 cm steaks at 96 h postmortem. Strip loin steaks were used to evaluate vacuum purge, cook loss, and Warner-Bratzler shear force (WBSF). Shoulder clods were processed to ground beef before processing into bologna. Consumer sensory panels comprised of untrained panelists were utilized for both strip steaks (n = 130) and bologna (n = 126) to evaluate overall liking, flavor liking, texture liking, toughness, juiciness, and off-flavor. Data was analyzed using Proc Mixed of SAS 9.4 (SAS Inst. Inc., Cary, NC).ResultsTreatment had no effect on HCW (P = 0.694), REA (P = 0.259), backfat (P = 0.780), USDA Yield Grade (P = 0.890), USDA Quality Grade (P = 0.877), and marbling score (P = 0.845). Although purge loss (P = 0.884) and cook loss (P = 0.149) were not affected by treatment, WBSF values were lower for CC than CON (1.6 vs. 2.23kg respectively; P = 0.001). Objective L* and b* values for bologna were different among treatments (P < 0.001) with CaOH2 being higher than all other treatments. Objective a* values were lower for H2O than CC and CaOH2 (P < 0.001) and higher for CC and CaOH2 than CON on Day 0 (P = 0.002 and P < 0.001 respectively). For steak sensory, no differences were found in flavor liking (P = 0.102), juiciness (P = 0.375), or off-flavor (0.313). Differences were found in overall liking (P = 0.008) with CC being more liked than CON (P = 0.013) and CaOH2 (P = 0.019). Texture liking (P < 0.001) for CC was higher than CON (P < 0.001), H2O (P = 0.021), and CaOH2 (P < 0.001). Toughness scores were lowest for CC (P < 0.001) compared to CON (P < 0.001), H2O (P = 0.015), and CaOH2 (P < 0.001). For bologna sensory, no differences among treatments were found in overall liking (P = 0.610), flavor liking (P = 0.707), texture liking (P = 0.828), juiciness (P = 0.371), and off-flavor (P = 0.716). A difference in toughness was found (P = 0.011) with H2O being more tough than CaOH2 (P = 0.008).ConclusionThe use of calcium hydroxide treatment in backgrounding diets of beef calves does not affect carcass characteristics or moisture loss, but does affect processed meat shelf life, and sensory characteristics for fresh steaks and bologna.

Effects of protein and fat concentration in coproduct-based growing calf diets on adipogenic and lipogenic gene expression, blood metabolites, and carcass composition

Crossbred calves (n = 30; age = 95 ± 1.7 d; BW = 179 ± 18 kg) were fed 1 of 5 growing diets: 1) corn-based control, 2) low-fat, low-protein coproduct blend, 3) high-fat, low-protein coproduct blend, 4) low-fat, high-protein coproduct blend, and 5) high-fat, high-protein coproduct blend for 112 d (growing phase) followed by a common corn-based finishing diet (additional 112 d; finishing phase). Calves were biopsied at 0, 112, and 224 d for transcriptional analysis via real-time quantitative PCR of 14 genes associated with adipogenesis and lipogenesis within the muscle. Serum was collected at d 0, 112, and 224 and analyzed for leptin, IGF-1, and GH concentration. Treatments were arranged in a 2 × 2 factorial. Data were analyzed using the MIXED procedures of SAS (SAS Inst. Inc., Cary, NC) to ascertain the effects of 2 protein levels, 2 fat levels, time, and any interactions. Increased protein and decreased fat in the growing diet resulted in a carryover effect that increased (P < 0.01) gene expression of PPARγ, insulin-induced gene 1, thyroid hormone responsive SPOT14 protein, ATP citrate lyase, adiponectin, diacylglycerol O-acyltransferase homologue 2, fatty acid binding protein 4, fatty acid synthase, phosphoenolpyruvate carboxykinase 1, and stearoyl-CoA desaturase as well as serum leptin concentrations between d 112 and 224. Expression of sterol regulatory element binding transcription factor 1 was increased (P < 0.01) at d 112 in steers fed high-protein, high-fat diets compared to those fed high-protein, low-fat diets. A fat × day interaction (P < 0.01) occurred for the expression of adiponectin receptor 2 and CCAAT/enhancer binding protein alpha, resulting in a carryover effect wherein low-fat diets fed during the growing phase increased expression of both genes at the end of the finishing phase (d 224). After slaughter, cattle fed the control during the growing phase tended (P = 0.09) to have greater marbling scores, whereas other carcass parameters were not different (P ≥ 0.13). These data indicate that feeding differing levels of dietary fat and protein during the growing phase does affect i.m. adipogenesis at the transcriptional level, but differences in gene expression were not sufficient to affect carcass quality among cattle fed coproducts.

Effects of isobutyrate supplementation in pre- and post-weaned dairy calves diet on growth performance, rumen development, blood metabolites and hormone secretion

Isobutyrate supplements could improve rumen development by increasing ruminal fermentation products, especially butyrate, and then promote the growth performance of calves. The objective of this study was to evaluate the effects of isobutyrate supplementation on growth performance, rumen development, blood metabolites and hormone secretion in pre- and post-weaned dairy calves. In total, 56 Chinese Holstein male calves with 30 days of age and 72.9±1.43 kg of BW, blocked by days of age and BW, were assigned to four groups in a randomized block design. The treatments were as follows: control, low-isobutyrate, moderate-isobutyrate and high-isobutyrate with 0, 0.03, 0.06 and 0.09 g isobutyrate/kg BW per calf per day, respectively. Supplemental isobutyrate was hand-mixed into milk of pre-weaned calves and the concentrate portion of post-weaned calves. The study consisted of 10 days of an adaptation period and a 50-day sampling period. Calves were weaned at 60 days of age. Seven calves were chosen from each treatment at random and slaughtered at 45 and 90 days of age. BW, dry matter (DM) intake and stomach weight were measured, samples of ruminal tissues and blood were determined. For pre- and post-weaned calves, DM intake and average daily gain increased linearly (P<0.05), but feed conversion ratio decreased linearly (P<0.05) with increasing isobutyrate supplementation. Total stomach weight and the ratio of rumen weight to total stomach weight tended to increase (P=0.073) for pre-weaned calves and increased linearly (P=0.021) for post-weaned calves, whereas the ratio of abomasum weight to total stomach weight was not affected for pre-weaned calves and decreased linearly (P<0.05) for post-weaned calves with increasing isobutyrate supplementation. Both length and width of rumen papillae tended to increase linearly for pre-weaned calves, but increased linearly (P<0.05) for post-weaned calves with increasing isobutyrate supplementation. The relative expression of messenger RNA for growth hormone (GH) receptor and 3-hydroxy-3-methylglutaryl-CoA synthase 1 in rumen mucosa increased linearly (P<0.05) for pre- and post-weaned calves with increasing isobutyrate supplementation. Blood concentrations of glucose, acetoacetate, β-hydroxybutyrate, GH and IGF-1 increased linearly (P<0.05) for pre- and post-weaned calves, whereas blood concentration of insulin decreased linearly with increasing isobutyrate supplementation. The present results indicated that isobutyrate promoted growth of calves by improving rumen development and its ketogenesis in a dose-dependent manner.

Effect of replacing a commercial pelleted calf meal with lucerne leaf-meal on performance of neonatal and transitional Holstein heifer calves

A study was conducted to (i) determine in vitro ruminal dry matter (DM) fermentation kinetics, effective rumen degradation of DM (EDDM), (ii) estimate energy fractions supply of lucerne leaf-meal (LLM) and composite diets of LLM with commercial pelleted calf meal and also (iii) determine the effects of substituting commercial pelleted calf meal with LLM on the intake, % ruminal nitrogen balance (RNB) and growth of the neonates (21–42 days old) and transition (43–56 days old) Holstein heifer calves. Forty-eight Holstein heifer calves were randomly assigned to three different dietary treatments in a complete randomised design of: (a) pelleted concentrate (PEL), (b) 65% pelleted concentrate: 35% LLM (P65 L35); (c) and 50% pelleted concentrate: 50% LLM (P50 L50). The study comprised of two experiments: neonatal (Experiment 1) and transition (Experiment 2) phases. Lucerne leaf-meal had gross energy of 16.2 MJ/kg and 25% crude protein DM. PEL diet was high in starch and bound protein compared with other diets. Inclusion of LLM in diets increased calcium levels but tended to decrease phosphorus levels. Calves were weaned at the age of 56 days. The feeds were incubated for 0, 4, 10, 18, 24 and 48 h using a DaisyII incubator. Rumen fluid was obtained from calves &lt;50 days old. Large Ruminant Nutrition System was used to predict %RNB and energy density of the diets during neonatal and transition phases. Higher mean EDDM levels were found with LLM inclusions whereas fractions a, a + b and c did not vary. Neonates on diet C had higher (P &lt; 0.05) daily DM and crude protein intakes, %RNB, total digestible nutrients, net energy at maintenance and net energy at gain during neonatal phase. Performance of calves was similar during the transition phase. LLM should be considered as a concentrate replacement in diets of neonates and calves.

Performance of crossbred dairy Friesian calves fed two levels ofSaccharomyces cerevisiae: intake, digestion, ruminal fermentation, blood parameters and faecal pathogenic bacteria

SUMMARYThe effect of feeding two levels ofSaccharomyces cerevisiaeon the performance of crossbred Friesian calves was investigated. Twenty-four neonatal male Friesian × Baladi calves (35·5 ± 0·25 kg of initial body weight) were randomly assigned in a completely randomized design into three experimental groups for 90 days (eight calves per group). Calves fed their diets without yeast (S. cerevisiae) were considered as Control, while the diets of other calves were supplemented daily either with 2·5 g (YL diet) or with 5 g (YH diet) of yeast per calf. Calves fed the YH diet showed increased feed intake, while dry matter and fibre digestibilities were increased in calves fed YH and YL diets. Calves fed YL and YH diets showed lower ruminal ammonia-N and higher total volatile fatty acids, acetate and propionate concentrations than Control calves. Both YH and YL calves showed increased plasma concentrations of total protein, globulin and glucose and decreased cholesterol and triglycerides concentrations. Calves’ final weight and daily gain were increased withS. cerevisiaeyeast supplemented diets. After 42 days of experiment,Clostridiumspp.,Escherichia coliandEnterobacteriaspp. counts were down to undetectable levels in the faeces of calves fedS. cerevisiaeadditive. It could be concluded that addingS. cerevisiaeto milk-fed calves increased feed utilization and improved pre-weaned calf performance and health status, reducing faecal pathogenic bacteria.

Technical note: Impact of a molasses-based liquid feed supplement on the feed sorting behavior and growth of grain-fed veal calves.

This study was designed to determine the effect of adding a molasses-based liquid feed (LF) supplement to a high-grain mixed ration on the feed sorting behavior and growth of grain-fed veal calves. Twenty-four Holstein bull veal calves (90.2 ± 2.6 d of age, weighing 137.5 ± 16.9 kg) were split into groups of 4 and exposed, in a crossover design with 35-d periods, to each of 2 treatment diets: 1) control diet (76.0% high-moisture corn, 19.0% protein supplement, and 5.0% alfalfa/grass haylage) and 2) LF diet (68.4% corn, 17.1% protein supplement, 9.0% molasses-based LF, and 4.5% alfalfa/grass haylage). Diets were designed to support 1.5 kg/d of growth. Data were collected for the final 3 wk of each treatment period. Feed intakes were recorded daily and calves were weighed 2 times/wk. Feed samples of fresh feed and refusals were collected 3 times/wk for particle size analysis. The particle size separator had 3 screens (19, 8, and 1.18 mm) and a bottom pan, resulting in 4 fractions (long, medium, short, and fine). Sorting was calculated as the actual intake of each fraction expressed as a percent of its predicted intake. Calves tended ( = 0.08) to sort for long particles on the control diet (110.5%) and did not sort these particles on the LF diet (96.8%). Sorting for medium particles (102.6%) was similar ( = 0.9) across diets. Calves sorted against short particles on the LF diet (97.5%; = 0.04) but did not sort this fraction on the control diet (99.4%). Calves sorted against fine particles (79.3%) to a similar extent ( = 0.2) on both diets. Dry matter intake was similar across diets (6.1 kg/d; = 0.9), but day-to-day variability in DMI was greater (0.5 vs. 0.4 kg/d; = 0.04) when calves were fed the control compared with the LF diet. Calves on both diets had similar ADG (1.6 kg/d; = 0.8) as well as within-pen variability in ADG (0.4 kg/d; = 0.7). The feed-to-gain ratio was also similar between control and LF diets (4.3 vs. 3.9 kg DM/kg gain; = 0.4). The results suggest that supplementation of a molasses-based LF to high-grain fattening veal calf diets can reduce variability in feed consumption, both within and across days.