Effects of milk replacer acidification and free-access feeding on early life feeding, oral, and lying behavior of dairy calves

Establishment of methanogen bacterial interactions during the preweaning period of dairy cattle

Ruminant livestock are major contributors to anthropogenic methane emissions in the United States and worldwide. Enteric methane is generated by methanogenic archaea residing in ruminant digestive tracts. Information on when methanogens colonize the gut and when they begin to interact with bacteria during the early phases of the ruminant life cycle is less explored. The objectives of this study were (i) to investigate the composition of the methanogenic archaeal community at birth and through the weaning transition and (ii) to determine if and when the methanogenic archaea begin to interact with bacteria in the lower gut of neonatal dairy calves. Ten female Holstein calves (approximately 45kg birth weight) were enrolled in the study. Fecal samples were collected every two weeks (Wk 2, 4, 6, 8, 10, and 12) between birth and weaning and analyzed for methanogenic archaeal diversity via 16S rRNA amplicon sequencing and quantitative real-time PCR (RT-qPCR). Estimates of alpha diversity (Observed species, and Shannon diversity index) and beta diversity (weighted and unweighted UniFrac distances) showed significant differences (P < 0.05) between archaeal communities across timepoints. Both 16S rRNA amplicon sequencing and RT-qPCR analyses revealed Methanobrevibacter was the most prevalent genus at Wk2, Wk4, and Wk6, whereas Methanosphaera gradually increased with time and was most abundant at Wk10 and Wk12. Correlation analysis revealed that Methanobrevibacter and Methanosphaera were inversely correlated with each other and formed distinct cohorts with specific bacterial lineages similar to those reported in the mature rumen, thus revealing that these associations are established during the preweaning period. Therefore, the preweaning period presents a window of opportunity to interfere with early-life methanogenic colonization with the ultimate goal of reducing enteric methane emissions without perturbing ruminal function later in the life of dairy cattle.

Invited review: The effect of milk feeding practices on dairy calf behavior, health, and performance-A systematic review

The aim of this systematic review was to summarize the literature assessing the effects of milk feeding practices on behavior, health, and performance on dairy calves. Peer-reviewed, published articles, written in English, directly comparing the effects of milk allowance, milk feeding methods, or milk feeding frequency on dairy calves were eligible for inclusion. Outcome measures could include sucking behavior, sucking on a teat (nutritive sucking, non-nutritive sucking on a teat), abnormal sucking behavior (non-nutritive sucking on pen fixtures, other oral behaviors, or cross-sucking), signs of hunger (vocalizations or unrewarded visits at the milk feeder), activity (lying time or locomotor play), feeding behavior (milk intake, starter intake, milk meal duration, or starter meal duration), growth (body weight or average daily gain), and health (occurrence of diarrhea, respiratory disease, or mortality). We conducted 2 targeted searches using Web of Science and PubMed to identify key literature. The resulting articles underwent a 2-step screening process. This process resulted in a final sample of 94 studies. The majority of studies investigated milk allowance (n = 69). Feeding higher milk allowances had a positive or desirable effect on growth, reduced signs of hunger, and increased locomotor play behavior during the preweaning period, whereas starter intake was reduced. Studies addressing health pointed to no effect of milk allowance, with no consistent evidence indicating that higher milk allowances result in diarrhea. Studies addressing milk feeding methods (n = 14) found that feeding milk by teat reduced cross-sucking and other abnormal oral behaviors. However, results on the effect of access to a dry teat were few and mixed. Milk feeding frequency (n = 14 studies) appeared to have little effect on feed intakes and growth; however, there is some evidence that calves with lower feeding frequency experience hunger. Overall, findings strongly suggest feeding higher volumes of milk using a teat; however, further work is needed to determine the optimal feeding frequency for dairy calves.

Calf management and welfare in the Canadian and US dairy industries: Where do we go from here?

The objective of this narrative review was to compare the results of the 2015 Canadian National Dairy Study and the 2014 US National Animal Health Monitoring System (NAHMS) Dairy Studies, with a specific focus on calf management and welfare, and to interpret these findings within more recent calf health research to describe where we need to go next in the North American dairy industry. Situating results of periodic national studies within the context of past and recent research provides an opportunity to gauge adoption of recommendations and best practices and to help identify persistent and new challenges that the industry is wrestling with to help guide research needs. Through this review of the 2 national studies, we identified several strengths of the Canadian and US dairy industries. In each area of calf health management, improvements relative to previous NAHMS studies and the published literature have been found in the level of mortality, amount of colostrum fed, housing, and the number of producers using pain control for disbudding and dehorning. There were, however, some areas that present clear opportunities for improvement. Specifically, although mortality levels have improved, a large number of calves die at birth, within the first 48 h of life, and during the preweaning period. To improve the health of calves in early life, producers could look at feeding high-quality colostrum at 10% of body weight in the first feeding, as well as feeding a larger amount of milk during the preweaning period. The barriers to making these management changes and improving overall calf health need to be identified in future studies. The majority of preweaning calves in Canada and the United States are housed in individual housing. This represents a clear opportunity for improvement because recent research has identified the positive aspects of group housing. Finally, with respect to pain control, improvements are needed (particularly in the United States) to ensure that pain management is provided when disbudding and dehorning calves. Although the science is clear on pain management, discussions with producers are needed to identify reasons for the lack of uptake.

Acidification of colostrum affects the fecal microbiota of preweaning dairy calves

Calf diarrhea is a leading cause of death in preweaning calves and it causes major economic losses to producers. Acidified milk has been shown to have beneficial effects on health and growth parameters in calves but there is little research into its effects on the microbiota, and few studies on the use of acidified colostrum. The purpose of this study was to compare how feeding acidified colostrum to calves at birth affects fecal microbiota from birth through 8 wk of age compared with calves fed nonacidified colostrum. In this study, 5 calves received acidified colostrum (treated group) and 5 calves received nonacidified colostrum (control group) at birth and at 12 h of age. All calves were subsequently fed acidified whole milk until weaning at 8 wk of age and had access to starter grain starting at d 3 and throughout the study. Fecal samples were collected at 24 h, 48 h, and at 1, 2, 3, 4, 5, 6, 7, and 8 wk of age. Samples were extracted for genomic DNA, PCR-amplified for the V1-V2 region of the 16S rRNA bacteria gene, sequenced, and analyzed using QIIME2. Bacterial richness (estimated by number of observed species) and bacterial diversity (estimated by Shannon diversity index) differed between time points but not between treatment groups, and both increased over time. Weighted and unweighted UniFrac analysis showed differences between bacterial communities across time points and treatments. Across all time points (lmer test), 6 bacterial genera were different between treatments: Faecalibacterium and unclassified Clostridiaceae were more abundant, whereas Atopobium, Collinsella, CF231, and unclassified Veillonellaceae were less abundant in treated versus control calves. Faecalibacterium is a butyrate-producing bacterium that has been linked to decreased prevalence of diarrhea in calves. Our results indicate that there is considerable flux in the calf microbiome through the neonatal period and weaning transition but that feeding acidified colostrum followed by acidified whole milk allowed early colonization of Faecalibacterium. Further studies are needed to verify the positive benefits of promoting Faecalibacterium on improving the health of preweaning calves.

A review of bovine colostrum preservation techniques

Preservation of colostrum for neonatal dairy calves has seldom been seldom in recent years, much of the peer reviewed literature having been published in the 1970s and 1980s. First milking colostrum is high in bioactive immune enhancers such as immunoglobulins, lactoferrins, lysozymes and cytokines and is vital to confer passive immunity to newborn dairy calves to promote their health, welfare and future productivity. Bovine colostrum is advisedly restricted from the bulk milk supply for the first 8 milkings post calving due to high somatic cell counts and the risk of antimicrobial residues. As such, many producers refer to 'colostrum' as not only the first milking post calving, but also the aformentioned 'transition' milk. Colostrum is preserved in order to protect supply for feeding when production may be poor or where there is a glut of colostrum such as in seasonal calving systems. There are multiple reasons for newborn calves not to have access to their dam's colostrum, including multiple births, acute mastitis or maladapted maternal behaviour, especially in first lactation heifers. Shortages in colostrum may also be precipitated by purposeful discarding of colostrum from cows infected with Mycobacterium avium subsp paratuberculosis and Mycoplasma bovis. Broadly, colostrum may be preserved using low temperature (refrigeration or freezing) or chemical preservatives. The aim of this scoping review article was to identify options for preservation and gaps in research and to propose best practice for colostrum preservation.

Effect of formic acid treatment on colostrum quality, and on absorption and function of immunoglobulins: a randomized controlled trial in Holstein dairy calves

Background

Good quality colostrum is characterized by high immunoglobulin concentration and low pathogen load. Some methods of pathogen reduction can decrease immunoglobulin concentration and potentially affect their function. Objectives were to determine the effect of formic acid treatment on colostral bacterial and immunoglobulin (IgG) levels before feeding, and serum immunoglobulin concentration and neutralizing capabilities after feeding. Fifteen female Holstein calf pairs born < 12 h apart from different dams were randomly assigned to receive four liters of either untreated pooled (both dams) colostrum (MC) or colostrum acidified to pH 4.0–4.5 (AC). Colostrum characteristics estimated; pH, bacterial load, IgG concentration, and neutralization of Infectious Bovine Rhinotracheitis (IBRV/BoHV-1), Bovine Viral Diarrhea (BVDV) Types 1 and 2. Blood samples were collected on days 1, 3 and monthly for 6 months and were analyzed for IgG, and both viral plus leptospiral neutralization, and total protein (day 3 only).

Results

Compared to MC (mean 6.7, SD 0.4; median 6.8, range 6.0–7.3), AC pH was significantly reduced (mean 4.3, SD 0.2; median 4.3, range 4.0–4.5; P < 0.001). Total coliform count (cfu/mL) was also reduced (MC mean 149, SD 444; median 1, range 0–1,700; AC mean 8, SD 31; median 0, range 0–120; P = 0.02). Colostrum IgG concentration was not significantly different between MC (mean 93.3, SD 39.7; median 92.8, range 36.7–164.4 g/L) and AC (mean 101.9, SD 36.7; median 108.3, range 33.8–164.4 g/L; P = 0.54). In calves, serum IgG peaked on day 3 (MC mean 26.1, SD 34.9; median 169.2, range 8.3–151.0 g/L; AC mean 30.2, SD 48.7; median 188.8, range 3.1–204.4 g/L; P = 0.77), and apparent efficiency of IgG absorption was not different between groups (MC mean 24.3, SD 11.4, median 25.3, range 8.6–51.3%; AC mean 22.6, SD 21.7, median 21.6, range 4.1–58.9%; P = 0.65). Thereafter, IgG levels declined but did not differ between groups. MC and AC serum neutralizing titers for IBRV, BVDV Types 1 and 2, or Leptospira interrogans serovars Canicola, and Pomona and L. borgpetersenii serovar Hardjo were not different.

Conclusions

Colostrum acidification significantly decreased bacterial load fed to newborn calves without affecting colostral IgG concentration or virus neutralization. In addition, acid treatment did not affect serum IgG concentration in calves or its activity against common pathogens.

Preparing Male Dairy Calves for the Veal and Dairy Beef Industry

Surplus male dairy calves experience significant health challenges after arrival at the veal and dairy beef facilities. To curb these challenges, the engagement of multiple stakeholders is needed starting with improved care on some dairy farms and better management of transportation. Differing management strategies are also needed if calves arrive at veal and dairy beef facilities under poor condition.

Effects of Milk Feeding Strategy and Acidification on Growth Performance, Metabolic Traits, Oxidative Stress, and Health of Holstein Calves

Effects of milk feeding strategy and acidification on calf growth, metabolic traits, oxidative stress, and health were evaluated in the first 78 days of life. Holstein calves (N = 48; 12 calves/treatment) were assigned to 1 of the 4 treatments in a 2 × 2 factorial arrangement of milk feeding strategy [6 L/d (MOD) or 12 L/d (HIGH) of milk] and acidification [non-acidified milk (NAM) or acidified milk (ACM)] on day 2. Calves were bucket-fed milk as follows: 6 L/d from days 2 to 49 for MOD and 6 L/d from days 2 to 49, 12 L/d from days 7 to 42, and 8 L/d from days 43 to 49 for HIGH calves. All calves were then fed 4 L/d from days 50 to 56. Starter and water were available ad libitum, while hay was fed at 5% of starter from day 64. Calves were weighed, measured, and blood (except days 14, 42 and 56) sampled on days 2, 14, 28, 42, 49, 56, 63 and 78. Data were analyzed using Mixed PROC of SAS with time as repeated measurements. Fecal scores, checked daily, were examined by the logistic regression using a binomial distribution in GLIMMIX procedure. There were no three-way interactions observed for all the parameters. We detected a milk feeding strategy × time interaction for starter intake, body weight, ADG, ADG/ME, FE, structural measurements, and glucose. Although, overall (558.0 vs. 638.6 g/d), HIGH calves tended to consume less starter compared to MOD, significant differences were only observed in week 8. The HIGH calves had greater ADG during days 2–14 (1.12 vs. 0.75 kg/d) and tended to have greater ADG on days 15–28 (0.79 vs. 0.55) and 29–42 (0.86 vs. 0.60) and lower on days 57–63 (0.11 vs. 0.38) compared to MOD calves. The HIGH calves had greater BW from days 28 to 78 compared to MOD, while NAM were bigger compared to ACM calves from days 49 to 78. The HIGH calves had lower overall feed and metabolizable energy efficiencies compared to MOD. Except for BW and heart girth, no milk acidification × time interaction was observed for starter intake, ADG, FE, or ADG/ME. Blood glucose in calves fed NAM-HIGH and ACM-HIGH were greater compared to those fed moderate milk volumes on day 28 only. Albeit, feeding strategy had no effect, calves fed ACM had lower likelihood of experiencing diarrhea (odds ratio = 1.32; 95% confidence interval: 1.018–1.698) compared to those fed NAM. Overall milk feeding strategy had no effect on growth, while milk acidification reduced growth in calves, despite lowering the likelihood of experiencing diarrhea.

Validation of 1-0 and instantaneous sampling for quantifying oral behaviors in milk-fed dairy calves

Oral behaviors, including feeding, drinking, grooming, and non-nutritive behaviors, are used as indicators of health and welfare in dairy calves, but continuous measurement of these behaviors can be labor intensive. Instantaneous sampling is often used to save labor but has only been validated for feeding behavior in calves. One-zero sampling may be an appropriate strategy well suited to capturing the rapid performance of non-nutritive behaviors. Our objective was to validate 1-0 and instantaneous sampling for measurement of oral behaviors around the time of bottle delivery against true values. Eleven Holstein heifer calves were housed individually, provided water, and fed a diet of starter grain and milk replacer (4.8-5.6 L/d step-up) via a bottle. When calves were 23 ± 7 d old, they were video recorded for 30 min before and after the morning 2.5 ± 0.2 L milk meal, from approximately 0900 to 1000 h. We measured ruminating, eating, drinking water, sucking milk, grooming, non-nutritive oral manipulation, and tongue flicks continuously and with instantaneous and 1-0 sampling at 5-, 10-, 30-, and 60-s intervals. We also examined the effect of instantaneous timing within these intervals. Estimates obtained through subsampling were compared with true values via regression analysis. The subsampling interval was determined to represent true values if the coefficient of determination ≥0.9, slope = 1, intercept = 0, and relative error <10%. Ruminating, drinking water, and eating were not performed by all 11 calves and were not included in the analysis. The proportions of time performing non-nutritive oral manipulation, grooming, and tongue flicks generated by continuous and 1-0 sampling were highly correlated but were consistently overestimated by 1-0 sampling, especially as calves spent more time engaged in these behaviors. Sucking milk was accurately represented at intervals of less than 30 s, likely due to most sucking bouts continuing for at least 150 s at a time and low between-calf variability compared with the other behaviors. Different start times within a given instantaneous interval resulted in wide variance in discrepancies between subsampling and continuous recording for all behaviors. We conclude that around milk feeding, 1-0 sampling is an appropriate choice to represent stimulus-elicited behavior, such as sucking milk in a milk-restricted system. However, time engaged in short, highly variable, or intermittent behaviors is not reliably captured via instantaneous or 1-0 sampling in the hour around bottle delivery.

Strategies for Feeding Unweaned Dairy Beef Cattle to Improve Their Health

In order to answer the question of whether nutritional interventions may help to reduce the incidence of respiratory disease in dairy beef calves at arrival, the present review is divided in three sections. In the first section, the nutrition of calves previous to the arrival from the origin farm to the final rearing farm is reviewed. In the second section, the possible consequences of this previous nutrition on gut health and immune status upon arrival to the rearing farm are described. The main consequences of previous nutrition and management that these unweaned calves suffer at arrival are the negative energy balance, the increased intestinal permeability, the oxidative stress, the anemia, and the recovery feed consumption. Finally, in the third section, some considerations to advance in future nutritional strategies are suggested, which are focused on the prevention of the negative consequences of previous nutrition and the recovery of the gut and immune status. Moreover, additional suggestions are formulated that will be also helpful to reduce the incidence of bovine respiratory disease (BRD) that are not directly linked to nutrition like having a control golden standard in the studies or designing risk categories in order to classify calves as suitable or not to be transported.

Effect of acidified milk feeding on the intake, average daily gain and fecal microbiological diversity of Holstein dairy calves

OBJECTIVE

To evaluate the effect of feeding acidified milk on the growth and fecal microbial diversity of dairy calves.

METHODS

Twenty healthy 3-day-old female Holstein calves with similar body weights were selected and randomly divided into two groups. One group was fed pasteurized milk (PM, Control), while the other was fed acidified milk (AM) ad libitum until weaned (day 60). The experiment lasted until day 180.

RESULTS

There was no difference in the nutritional components between PM and AM. The numbers of Escherichia coli and total bacteria in AM were lower than in PM. At 31 to 40 and 41 to 50 days of age, the milk intake of calves fed AM was higher than that of calves fed PM (p<0.05), and the solid feed intake of calves fed AM was higher than that of calves fed PM at 61 to 90 days (p<0.05). The average daily gain of calves fed AM was also higher than that of calves fed PM at 31 to 60, 61 to 180, and 7 to 180 days (p<0.05). The calves fed AM tended to have a lower diarrhea rate than those fed PM (p = 0.059). Bacteroides had the highest abundance in the feces of calves fed AM on day 50, while Ruminococcaceae_UCG_005 had the highest abundance in the feces of calves fed AM on day 90 and calves fed PM on days 50 and 90. At the taxonomic level, the linear discriminant analysis scores of 27 microorganisms in the feces of calves fed AM and PM on days 50 and 90 were higher than 4.0.

CONCLUSION

Feeding AM increased calf average daily gain and affected fecal bacterial diversity.

Comparison of Reconstituted, Acidified Reconstituted Milk or Acidified Fresh Milk on Growth Performance, Diarrhea Rate, and Hematological Parameters in Preweaning Dairy Calves

Simple Summary

The preweaning phase is the period for the rapid growth and development of dairy calves. During this period, dairy calves receive their nutrients through milk. Feeding hygienic milk is of great benefit to optimum growth rate and health status of dairy calves. Previous studies focused on the effects of hygienic milk by acidification on dairy calves’ health and growth. Reconstituted milk, as the common source of milk, is being used in dairy calves feeding. However, no previous studies reported the effects of feeding acidified reconstituted milk on dairy calves’ health and growth. Our study will provide the evidence that the acidification of reconstituted milk had positive effects on growth performance and health status of preweaning dairy calves.

Abstract

The present experiment was carried out to assess the effects of reconstituted milk (RM), acidified reconstituted milk (ARM), and acidified fresh milk (AFM) on growth performance, diarrhea rate, and hematological parameters of preweaning dairy calves. For this purpose, a total of 27 Holstein female calves (one month of age) with initial body weight of (67.46 ± 4.08) kg were divided into three groups in such a way that each group contained nine calves. Calves were housed individually, and starter was offered ad libitum to each calf. The dietary treatments were RM, ARM, and AFM. The highest milk intake was observed in calves receiving AFM as compared to other treatments (p < 0.01). Calves fed AFM had more feed intake than those fed ARM and RM (p < 0.01). Feed efficiency was significantly lower for calves offered ARM than those offered RM and AFM (p < 0.01). A lower withers height growth was found for calves fed RM than those fed ARM and AFM (p <0.05). Diarrhea rate and white blood cell (WBC) and lymphocytes (LYM) counts were greater for calves fed RM than those fed ARM and AFM (p < 0.05). These findings suggested that ARM and AFM had positive effects on growth performance and health status of the preweaning dairy calves.