Milk Replacer Research Articles

Relationship between feeding protocols and their cost with body development of lactating calves in family milk-production units

Objective: Characterize the feeding protocols and feeding costs, as well as their relationship with the body development of lactating calves until weaning in family milk-production units (FMPU). Methodology: A prospective observational cohort study was carried out. The feeding protocol, and its cost were recorded, in addition, the daily gains in weight (DWG) and height (DHG) between birth and weaning of 193 calves (n=12 FMPU). The information was subjected to descriptive statistics and analysis of variance. Results: In some FMPU, up to 5 feeding protocols were used, and calves with 49 and 138 days until weaning. The predominant feeding consisted of milk replacer plus starter concentrate (28.5%). The costs of the feeding protocols (1162 to 2395 pesos), as well as the DWG (0.346 to 0.721 Kg/day) and DHG (0.114 to 0.216 Cm/day), were statistically different between FMPU (P<0.01). The most expensive feeding protocol had a DWG of 0.555 kg/day and a DHG of 0.161 cm/day. Limitations of study/implications: The nutrient contributions of the feeding protocols were not determined, consequently, whether they covered the calves' nutritional requirements. Conclusions: In FMPU, there is a lack of standardization in feeding protocols and a high variation in their costs, as well as in the duration to weaning. The body development of the calves is suboptimal, influenced by the feeding protocol, where the highest cost is not reflected in the best body development rate.

Influence of Heat Treatment and Lactic Acid Fermentation on the Physical and Chemical Properties of Pumpkin Juice.

Pumpkin is a highly nutritious plant, rich in valuable nutrients that benefit human health. Due to the high perishability of this fruit, the production of pumpkin juice is a practical way to use it effectively. Recently, fermented vegetable juices have been used as a dairy alternative due to their nutritional and potential probiotic properties. This study investigated the fermentation of pumpkin juice using different strains of lactic acid bacteria (LAB), with and without heat treatment. The effects of fermentation on microbial growth, pH, acidity, extract, sugars, carotenoids, polyphenols, and antioxidant properties were analyzed. The heat-treatment process did not greatly impact the dry matter content, pH, acidity, extract, or sugar content. However, it led to a reduction in carotenoid and polyphenol levels. During fermentation, there was a consistent decrease in pH and an increase in total acidity, with no noticeable differences between bacterial strains regarding their influence on these parameters. The study revealed that there were no distinctions between LAB strains in their effects on pH, acidity, and carotenoid content in fermented pumpkin juice. Nonetheless, both L. sakei and L. plantarum proved to be effective in the fermentation process, with L. sakei demonstrating greater adaptability. The expected pH, acidity, and sugar content changes were consistently observed throughout the fermentation process. Overall, results confirm the efficacy of the used Lactobacillus strains in fermenting pumpkin juice and highlight the potential impact of heat treatment on the nutritional composition of the juice. The purpose of thermal processing of pumpkin juice, which is conducted with lactic acid fermentation, is crucial for the food industry. It extends the product's shelf life, improves its nutritional and taste profiles, and guarantees its microbiological safety.

Effect of pilot-scale high-temperature short-time processing on the retention of key micronutrients in a fortified almond-based beverage: implications for fortification of plant-based milk alternatives.

The effect of thermal processing treatments on key micronutrients in fortified almond-based beverages has not been well characterized. An almond-based beverage was produced in a pilot plant, fortified with vitamin A palmitate, vitamin D2, riboflavin (vitamin B2), calcium carbonate, and zinc gluconate, and was processed using various high-temperature short-time (HTST) pasteurization treatments. Naturally present micronutrients in the base ingredients included several B vitamins (vitamin B1 [thiamin], total vitamin B3 [sum of nicotinamide and nicotinic acid], and total vitamin B6 [sum of pyridoxal, pyridoxamine, and pyridoxine]) and minerals (magnesium, phosphorus, and potassium). The prepared almond-based beverage was homogenized and thermally processed using HTST pasteurization with a temperature range from ~94 to 116°C for a constant time of 30 s. The samples were analyzed for vitamin A palmitate, vitamin D2, target B vitamins (thiamin, riboflavin, total vitamin B3, and total vitamin B6), and minerals (magnesium, phosphorus, potassium, calcium, and zinc). The results showed that amounts of vitamin A, vitamin D2, riboflavin, and total vitamin B6 did not significantly (p > 0.05) change after the HTST treatments, whereas thiamin significantly (p < 0.05) decreased by 17.9% after HTST treatment at 116°C. Interestingly, total vitamin B3 content significantly (p < 0.05) increased by 35.2% after HTST treatment at 116°C. There was no effect of processing on the minerals that were monitored. The results from this study indicate that the majority of key micronutrients assessed in this study are stable during HTST processing of an almond-based beverage and that fortification of plant-based milk alternatives may be a viable process to enhance the micronutrient content consumers receive from these products.

The Effects of Restricted and Ad Libitum Milk Feeding on Growth and Health of Calves

In recent years, there has been a growing concern among consumers regarding animal welfare and their requirements, leading to an increased interest in exploring new approaches to calf rearing. Therefore, the aim of this study was to investigate the effects of milk feeding levels on the growth, feed intake, and blood variables of group-raised calves during the suckling period. Ten Holstein calves, 5 in each group, were used in the study when they were five years old. The calves were acclimated to an automated feeder during the initial 19 days of the experiment, and their initial LWs were recorded after weighing them again. The study concluded upon weaning the calves when they were sixty years old, with a total duration of 36 days The calves in the first group (G1) were provided with a total of 4 L/day of milk replacer, divided into 2 L servings in the morning and evening. Conversely, calves in the second group (G2) were allowed a maximum intake of 12 L/day of milk replacer, mimicking the natural sucking behaviour, with feedings in the morning (05:00-08:00), midday (10:00-13:00), and evening (16:00-20:00). Despite no significant differences in the LW, total and daily LW gains, and body measurements averages between of the groups, calves in G1 consumed more starter feed compared to those in G2 (P

Impact of early weaning and nutritional interventions on growth performance, digestive metabolism, and serum biomarkers in lambs: A biomechanical perspective

The aim of this study was to investigate the effects of early weaning and nutritional interventions on growth performance, nutrient digestion and metabolism, and serological indices of hu sheep lambs, with a view to providing a basis for the feasibility of early weaning of hu sheep lambs under conditions of supplemental milk replacer. Ninety neonatal hu sheep lambs were weaned at 21 days (n = 60) (divided into two groups: early weaned, EW; and resveratrol-fed, RSV) as well as 49 days (n = 30) (control group, CON) weaning, and the trial period was 90 days. The results showed that: 1) there was no significant difference (P &gt; 0.05) in the initial and final weights of the lambs, and the average daily gain (ADG) of the EW and RSV groups was significantly lower than that of the CON group (P &lt; 0.05) from 31 to 45 days of age. Early weaned lambs were more susceptible to weaning stress compared to late weaned lambs and the effect of nutritional intervention (feeding resveratrol) on lamb growth performance was not significant. 2) The apparent digestibility of crude protein (CP) in the experimental group was significantly lower than that of the control group (P &lt; 0.05), and the nitrogen intake, net protein utilization and protein biological value indexes of lake lambs in the experimental group were significantly different from those of the control group (P &lt; 0.05). 3) Early feeding of resveratrol was not significant in improving the digestive metabolism of nutrients. 4) Early weaning as well as the addition of resveratrol had a significant effect on the serum GLU and TC indexes of the lambs (P &lt; 0.05), but did not show a significant effect on any of the other indexes.

PSVI-1 Supplemented milk replacer improves feed transition of dairy bull-calves

Abstract Neonatal calves are affected by pathogenic infections, compounded by stress, leading to enteric and respiratory disorders accounting for about 7.8% mortality rate and annual treatment costs exceeding $250 million. Federal restrictions on antibiotic use due antimicrobial resistance in humans has opened the door for viable alternatives like rumen enhancements which have been reported to aid the establishment of beneficial rumen flora leading to improved health and performance. It is hypothesized that nutritional formulation of milk replacers to help the calf prevent or cope with diarrhea can provide a leeway that will ensure better animal performance and transition to solid feed. The objective of study was to evaluate the performance of dairy bull-calves fed nutritionally supplemented milk replacers. Three milk replacers were tested with or without supplementation of metabolic enhancements (Control: no metabolic enhancer; Added: milk replacer with metabolic enhancer added at the time of mixing milk in shuttle; Composite: produced along with metabolic enhancer. Dairy bull-calves (n = 60; 2 to 5 d-old) were grouped into three treatments of milk replacers. The study lasted for 10 wk; 6 wk of milk-feeding and 4 wk of calf starter feeding. Body weights (BW) were taken on a weekly basis, while calf starter intake was measured daily and data were analyzed using one-way analysis of variance. Calves fed milk replacer with composite metabolic enhancer recorded the greatest intake and final BW over the 10-wk period. Calves fed milk replacer with added metabolic enhancer at the point of milk mixing recorded the poorest data in terms of BW gain and final BW. Calves fed metabolic enhancer, either added or composite recorded a better weaning and transition to solid feed from milk feeding. Calves fed control milk replacer experienced a poor transition from milk feeding to solid feed. It is concluded that composited rumen metabolite enhancers in milk replacer supported greater starter intake, average daily gain and better transition of calves to solid feed, and is recommended for the feeding of neonatal calves.

PSXIII-1 Sensory additives improved the recovery of commercially marketed and transported unweaned dairy beef calves at rearing farm arrival

Abstract Calf recovery after arrival at the rearing farm in unweaned calves is impaired by periods of stress, feed restriction and fasting during marketing and transportation. The use of feed additives to enhance intake at arrival could be a strategy to minimize those negative effects. A total of 72 calves (71.4 ± 1.72 kg) gathered in a commercial assembly center and transported 9 h to a rearing farm were used to evaluate the effect of a sensory additive (SA) on performance in calves fed 2 L of milk replacer twice daily at 12.5% and ad libitum concentrate feed. Calves were allocated in 8 pens and distributed in 2 treatments (4 pens/treatment): calves fed a concentrate without SA since the beginning of the study (arrival to the rearing farm after transport) until weaning (CON; n = 36); calves fed a concentrate containing SA (SEN; n = 36) from arrival until weaning. Calf body weight (BW) and pen intake were recorded weekly. On d 21 of the study, calves were partially weaned and only milk replacer was offered in the morning, and on d 28 all calves were completely weaned. The study lasted 35 d. Data were analyzed with a mixed-effects model. Average daily gain was greater (P = 0.04) for SEN calves compared with CON calves (0.68 ± 0.019 kg/d and 0.61 ± 0.019 kg/d, respectively). Final BW of SEN calves (95.5 ± 0.89 kg) tended (P = 0.06) to be greater compared with BW of CON calves (93.1 ± 0.89 kg). Finally, average concentrate intake was greater for SEN calves (0.89 ± 0.023 kg/d) compared with CON calves (0.79 ± 0.023 kg/d). Unweaned dairy beef calves receiving sensory additive improved concentrate intake and growth at farm arrival improving their recovery.

PSIII-12 Dynamics of neonatal dairy calf behaviors and their association with early gut microbiota

Abstract The behavior of dairy cattle can be both an indicator and a determinant of their productivity and health. Additionally, animal behavior is also associated with their gastrointestinal microbiota through the bi-directional pathways of the gut-brain axis, influencing nutrient utilization and gut health. Few studies have looked at the dynamics of neonatal calf behaviors and their associations with early microbiota development. Therefore, the objective of this study is to observe feeding behaviors and activity of neonatal dairy calves and investigate its associations with the diversity and composition of early-stage gut microbiota. We used Holstein-Angus crossed calves (n = 25) raised in individual outdoor hutches and bucket-fed milk replacer twice daily. The number of milk exposures until calves were successfully bucket trained was recorded, along with milk consumption times during the AM feedings on d 7, 11, and 14. We also monitored the activity of the calves using HOBO Pendant G Data Logger accelerometers secured on the right hind leg of each calf to monitor standing and lying behavior from d 3 to d 13. Fecal samples were collected from the recto-anal junction of the calves at d 7 and 14 after birth and gut microbiota were analyzed using full-length 16S rRNA gene amplicon sequencing on an Oxford Nanopore sequencer. The Generalized Linear Model (GLM) was applied to evaluate effects of gender and birth weight on behavior and gut microbiota using RStudio 4.2.1. The Linear discriminant analysis Effect Size (LEfSe) was used to determine the unique bacterial species for each behavioral group. The results revealed that there was no influence of sex or birth weight on bucket training or consumption time; however, male calves exhibited significantly increased total standing time compared with female calves. We found no significant difference in microbiota between fast-learning calves (one milk exposure; n = 3) and slow-learning calves (5 or more exposures; n = 3). We observed greater alpha diversity of slow drinking calves (top 25%; n = 6) compared with fast drinking calves (top 25%; n = 6) on d 7 (Chao1; P = 0.03). The LEfSe analysis identified Akkermansia muciniphilia to be more abundant in fast drinking calves, and Megasphaera elsdenii to be more abundant in slow drinking calves. Additionally, a trend of differing microbiota composition was observed between the most active and least active calves (n = 4 per group) on d 14 (Bray-Curtis; P = 0.1), and many Prevotella species were more abundant in the most active calves. In conclusion, this study sheds light on the gut-brain axis of neonatal dairy calves at the species-level and provides further insights into cognitive, consumptive, and active behaviors.

247 Interaction between colostrum and milk replacer supply on growth, development and fecal consistency of dairy surplus calves

Abstract This study examined the interactions between early life nutrition strategies and their impact on growth, development, and fecal consistency in surplus bull calves. Holstein-Friesian bull calves [n = 120; body weight (BW) = 43.1±3.56 kg] were enrolled. In the first 12 h after birth, calves were fed either 2 L (100 g of IgG) or 6L (300 g of IgG) of colostrum replacer (CR) to obtain either failure (F) or successful (S) transfer of passive immunity, respectively. Upon arrival at the facility, serum IgG concentrations were measured; therefore, F and S calves were identified accordingly and randomly assigned to one of two milk replacer (MR) feeding schemes: Moderate (Mod; ~8 L) or Low (Low; ~4 L). In total, there were 4 treatments resulting from the 2 × 2 factorial design: F-Mod, F-Low, S-Mod, S-Low (n = 30/treatment). Calves were individually housed and fed twice daily until d 42, gradually weaned until d 56, and had free access to straw and water during the study. On d 22, a calf pelleted starter was offered. To evaluate organ and gastroinstetinal tract development, 10 calves/treatment were euthanized at 84 d of age. Other measurements include weekly BW, daily intakes, and daily fecal score until d 21. Data were analyzed by PROC MIXED in SAS accounting for the fixed effects of block, CR, MR, and time, and their interaction. Time entered the model as a repeated statement, and initial BW was used as a covariable when appropriate. Initial BW was not different across treatments, whereas serum IgG was greater in S calves (S = 1,962.9 vs. F = 941.0 mg IgG/dL). During the study, BW was influenced by both CR (P = 0.001) and MR (P &amp;lt; 0.001), where S and Mod calves consistently exhibited greater BW when compared with F and Low calves, respectively. At d 84, Mod calves (F-Mod and S-Mod) were on average 18 kg heavier than Low calves. Similarly, Mod calves exhibited greater fresh tissue weights in the liver, pancreas, spleen, and both the small and large intestines (P &amp;lt; 0.05). Starter intake was influenced by MR (P &amp;lt; 0.001), with Low calves having the greatest intake before and during weaning. However, post-weaning starter intake was greater (P = 0.010) in Mod calves. Fecal consistency was influenced by CR (P = 0.001) and MR (P &amp;lt; 0.001), with S and Low calves having improved fecal consistency. Although no interactions were observed between CR and MR, these findings underscore the importance of considering both colostrum and MR levels in calf nutrition management to optimize growth and improve animal welfare during the early stages of life.

167 Using ‘omics’ to optimize nutrition and health outcomes

Abstract It is clear that diet is linked with health outcomes, yet we are still far from fully understanding the impact of diet on systemic metabolic health. In the new era of ‘omics’ technology, the ability to optimize nutrition across the lifespan of companion animals is within reach. We have been using ‘omics’ technologies to understand how changes in diet composition impact metabolism using a neonatal piglet model. By measuring the composition of sow milk over the first week of lactation, we created an optimized pig milk replacer, and studied the impact of varying the whey protein composition of the milk replacer using a combination of metabolomics on blood, urine, liver, and brain tissue, as well as transcriptomics of intestinal, liver and brain tissue. Our results revealed a substantial impact of the type of whey protein on piglet metabolism that included differences in cortisol, blood and tissue amino acid profiles, and immunity. This work paves the way for additional studies to optimize animal nutrition in the neonatal period and beyond.

509 Growth and health of Holstein and Holstein x Angus calves from birth to the end of the grower phase

Abstract Feedlot growth performance and carcass traits often differ between Holstein and dairy-beef crossbred calves. However, little is known about their performance and health during the growing phase when reared under similar conditions. This study aimed to compare purebred Holstein (n = 20) and Holstein x Angus crossbred (n = 20) steers from birth until the end of the grower phase. Male calves sourced from one commercial farm arrived at a calf rearing facility at 4.7 ± 1.94 d of age. Calves were fed milk replacer (24 % CP, 20% fat) twice daily at 12 % of birth body weight (BW) for the first 2 wk after arrival and 15 % BW thereafter until wk 6. Calves were gradually weaned from wk 7 to 9. Calves were offered starter (21 % CP, 28% starch) ad libitum until wk 12, and were fed a grower diet (15 % CP, 56 % starch) until wk 32. Milk intake was recorded daily and starter intake on a weekly basis. Once on the growing diet, feed intake was recorded daily using automated feed bins (Roughage Intake Control system, Hokofarm Group). Until wk 12, fecal and respiratory scores were recorded twice daily to estimate the incidence of disease, BW was measured weekly and frame measurements (hip and wither heights, and heart and chest girth) were recorded on wk 4, 7 and 12. From wk 12 to 32, BW and frame measurements were recorded monthly. Data were analyzed using PROC GLIMMIX (SAS 9.4), with breed as fixed, and calf and time as random effects. There were no differences between breeds in initial BW (P = 0.69), proportion of days with diarrhea (P = 0.21) or respiratory disease (P = 0.11), intake of milk (P = 0.45), starter (P = 0.83) or grower diet (P = 0.28). Crossbred calves tended to have greater average daily gain during the rearing phase (P = 0.07) and were growing 250 g/d faster than Holstein calves throughout the growing phase (P &amp;lt; 0.01). Thus, at the end of the growing phase, crossbred calves were 33.5 kg heavier than Holstein calves and had a better feed conversion rate (P &amp;lt; 0.01). During the growing phase, crossbred calves had larger heart and chest girths (P &amp;lt; 0.01) than Holstein calves, whereas hip and wither heights were higher (P &amp;lt; 0.01) for Holstein calves throughout the study. Overall, crossbred calves had greater average daily gain and improved feed conversion rate than Holstein calves during the growing phase, but it remains unknown if these differences will affect their feedlot performance.

Exploring the Diversity and Potential Use of Flower-Derived Lactic Acid Bacteria in Plant-Based Fermentation: Insights into Exo-Cellular Polysaccharide Production.

Isolation of new plant-derived lactic acid bacteria (LAB) is highly prioritized in developing novel starter cultures for plant-based fermentation. This study explores the diversity of LAB in Danish flowers and their potential use for plant-based food fermentation. A total of 46 flower samples under 34 genera were collected for LAB isolation. By introducing an enrichment step, a total of 61 LAB strains were isolated and identified using MALDI-TOF and 16S rRNA sequencing. These strains represent 24 species across 9 genera, predominantly Leuconostoc mesenteroides, Fructobacillus fructosus, Apilactobacillus ozensis, and Apilactobacillus kunkeei. Phenotypic screening for exo-cellular polysaccharide production revealed that 40 strains exhibited sliminess or ropiness on sucrose-containing agar plates. HPLC analysis confirmed that all isolates produced exo-cellular polysaccharides containing glucose, fructose, or galactose as sugar monomers. Therefore, the strains were glucan, fructan, and galactan producers. The suitability of these strains for plant-based fermentation was characterized by using almond, oat, and soy milk. The results showed successful acidification in all three types of plant-based matrices but only observed texture development in soy by Leuconostoc, Weissella, Lactococcus, Apilactobacillus, and Fructobacillus. The findings highlight the potential of flower-derived LAB strains for texture development in soy-based dairy alternatives.

Enhancing protein content and lubrication behavior of plant-based milk with microparticulated wheat gluten protein via SS-SH interchange

The protein fortification and mouthfeel improvement (achieving dairy-like lubrication properties) in plant-based dairy alternatives have consistently been challenging tasks. To achieve this task, we developed a fully plant-based milk product by enhancing lubrication through microparticulated wheat gluten particles. By utilizing a combination of pH shifting, disulfide bond reductants, and high-pressure microfluidization, SH-SS exchange reactions were successfully induced, leading to the preparation of microparticulated wheat gluten particles with a particle size ranging from 1 to 2 μm and excellent dispersion properties. Introduction of a thiol-blocking agent confirmed the dominance of disulfide bonds in particle formation. The findings demonstrated that even at a high protein concentration of 15%, microparticulated wheat gluten sample maintained good flowability. Friction analysis revealed that the micro-particulated gluten protein treated with a disulfide bond reducing agent (GRM) exhibited a lower friction coefficient compared to other samples. Upon the addition of oat milk, GRM effectively reduced the coefficient of friction while increasing the protein content (5 wt%), achieving a lubrication effect similar to that of microparticulated whey protein. This study provides a novel solution for the preparation of microparticulate wheat gluten and enhances its incorporation into plant-based dairy products, offering a new approach to developing high-protein plant-based dairy products with improved mouthfeel and texture.

Towards more sustainable, nutritious, and affordable plant‐based milk alternatives: A critical review

AbstractThe consumer market has seen a surge in various types of plant‐based milk alternatives (PBMAs), driven by factors such as sustainability, ethics, and the availability of diverse options. However, the global adoption of PBMAs is still hindered by potential nutritional concerns and cost‐ineffectiveness. It is therefore paramount to understand the status and challenges of these alternatives, encompassing production, stabilization strategies, nutrition and health, digestion, and environmental impacts. This review provides a comprehensive examination of these aspects. We begin by scrutinizing the production processes and formulation strategies of PBMAs, followed by an exploration of fundamental stabilization aspects, including homogenization, emulsification, thickening, and quantitative measurements of stabilization. Additionally, we discuss their nutrition facts and potential health benefits, as well as potential differences in the digestion of nutrients from PBMAs. Importantly, their challenges and future directions are discussed individually, highlighting the need for a fundamental understanding and effective food technologies to develop sustainable, nutritious, tasty, and affordable PBMAs. For example, several critical aspects involve maximizing the use of plant materials (e.g., proteins, fibers, and bioactive compounds) and using reliable and unified life cycle analyses to guide the development. This review offers valuable insights for researchers, food technologists, and consumers seeking to navigate and develop the landscape of PBMAs effectively.

Early-life milk replacer feeding mediates lipid metabolism disorders induced by colonic microbiota and bile acid profiles to reduce body weight in goat model

BackgroundDysregulation of lipid metabolism and its consequences on growth performance in young ruminants have attracted attention, especially in the context of alternative feeding strategies. This study aims to elucidate the effects of milk replacer (MR) feeding on growth, lipid metabolism, colonic epithelial gene expression, colonic microbiota composition and systemic metabolism in goat kids compared to breast milk (BM) feeding, addressing a critical knowledge gap in early life nutrition.MethodsTen female goat kids were divided into 2 groups: those fed breast milk (BM group) and those fed a milk replacer (MR group). Over a period of 28 d, body weight was monitored and blood and tissue samples were collected for biochemical, transcriptomic and metabolomic analyses. Profiling of the colonial microbiota was performed using 16S rRNA gene sequencing. Intestinal microbiota transplantation (IMT) experiments in gnotobiotic mice were performed to validate causality.ResultsMR-fed pups exhibited reduced daily body-weight gain due to impaired lipid metabolism as evidenced by lower serum and liver total cholesterol (TC) and non-esterified fatty acid (NEFA) concentrations. Transcriptomic analysis of the colonic epithelium revealed upregulated genes involved in negative regulation of lipid metabolism, concomitant with microbiota shifts characterized by a decrease in Firmicutes and an increase in Actinobacteria. Specifically, genera such as Bifidobacterium and Prevotella were enriched in the MR group, while Clostridium and Faecalibacterium were depleted. Metabolomics analyses confirmed alterations in bile acid and fatty acid metabolic pathways. IMT experiments in mice recapitulated the metabolic phenotype observed in MR-fed goats, confirming the role of the microbiota in modulating host lipid metabolism.ConclusionsMilk replacer feeding in goat kids disrupts lipid metabolism and gut microbiota dynamics, resulting in reduced growth rates and metabolic alterations. These findings highlight the importance of early nutritional intervention on metabolic programming and suggest that modulation of the gut microbiota may be a target for improving growth and metabolic health in ruminants. This study contributes to the understanding of nutritional management strategies in livestock and their impact on animal health and productivity.

Risk of BSE transmission when fishmeal derived from fish fed bovine spray-dried red blood cells is included in calf milk replacers

The use of residual streams from agricultural production and food consumption containing animal proteins entails the risk of disease transmission as illustrated by the epidemics of bovine spongiform encephalopathy (BSE) and African swine fever. To combat this risk, the use of animal proteins in livestock feed was banned in the European Union, resulting in a drain of valuable proteins from the agricultural system. With an increasing call for a circular food system, the use of residual streams as a feed ingredient needs to be reconsidered with the associated disease risks being assessed and mitigated where needed. In this study, we assessed the BSE risk of bovine spray-dried red blood cells (SDRBC) as an ingredient of aquafeed. Fish fed with bovine SDRBC could indirectly result in exposure of ruminants to BSE infectivity because one of the exemptions of the feed ban is the use of fishmeal as an ingredient in calf milk replacers. A quantitative risk model was built to evaluate the BSE infectivity present in blood sourced from a slaughtered BSE-infected cow and the reduction of infectivity due to processing steps along the production chain. The end point of the model was the BSE infectivity, expressed in cattle oral ID50 (CoID50), reaching calves fed calf milk replacer containing fishmeal, and the corresponding probability that this will result in at least one new BSE infection.The expected BSE infectivity in blood from a BSE-infected cow at the clinical end state of infection is 0.75 CoID50 (median value). Infectivity in blood mainly results from cross-contamination with brain tissue during stunning at the slaughterhouse. The initial infectivity is reduced along the pathway from slaughtered cow to calf milk replacer, with the highest reduction achieved by clearance of infectivity by fish fed bovine SDRBC as an ingredient of aquafeed, although this parameter has high uncertainty. The final infectivity reaching calves via inclusion of fishmeal in calf milk replacer is estimated to be very low (median value: 1.1 × 10−5 CoID50). Assuming an exponential dose-response model, this corresponds with an expected probability that < 10 out of a million slaughtered BSE-infected cows will result in new BSE infections, which is far below the threshold value of 1 for the basic reproduction number (R0) to initiate a new epidemic. We thus conclude that it is very unlikely that the use of bovine SDRBC as ingredient of aquafeed will result in a new BSE epidemic in cattle. What-if analysis indicated that this conclusion is robust, despite high uncertainty for some input parameters.

Male Holstein calves fed a milk replacer and pelleted calf starter containing a botanical extract or a direct fed microbial (DFM) alone or in combination

Botanical extracts (BE; Apex, Adisseo, North America, Atlanta, GA) are known to enhance DMI and gut health, while direct fed microbials (DFM), such as a lactobacillus acidophilus fermentation product (EX: Excel; Pacer Technology, Inc., Murtaugh, ID), has demonstrated improved gut health and growth performance when fed to growing neonatal Holstein calves. The hypothesis was this combination may be synergistic to neonatal calf growth performance and intestinal health. Eighty 2-5-d old Holstein bull calves were blocked by BW and randomly assigned to 1 of 4 treatments arranged using a randomized complete block design. Treatments were: 1) Control: no additives; 2) BE added at 496 mg/kg to the calf starter (CS); 3) EX added to the CS at 2.50 g/kg with EX added to the milk replacer (MR) at 5 g/d; and 4) BE&EX: BE and EX added to CS at same rates and added EX to MR. Calves received 0.283 kg MR in 1.9 L fed 2 x/d for the first 14 d, then increased to 0.42 kg in 2.84 L fed 2x/d through d 35, followed by 0.42 kg MR in 2.84 L fed 1x/d through d 42, followed by weaning. The CS was a 25% CP DM basis mini-pellet and the MR was a 22:20 (CP:fat) fed 2x/d at 0630 and 1800 h along with free choice water. Weaning occurred after d 49 of the 70-d experiment. Calves fed CS EX alone demonstrated greater BW gain compared with calves fed BE&EX with calves fed Control and BE being intermediate and similar (63.9, 63.5, 65.0, and 59.7 kg for Control, BE, EX, and BE&EX, respectively). Total DMI (MR+CS) was lower for calves fed BE&EX compared with calves fed the remaining treatments (116.5, 114.2, 116.4, and 104.9 kg). The feeding of a BE in combination with EX (DFM) to neonatal calves reduced BW during wk 8, 9, and 10 and reduced 0-70 d ADG (874.7, 870.0, 889.7, and 817.6 g/d) compared with calves fed the remaining treatments. Calves fed BE&EX demonstrated the lowest calf starter intake during wk 4 through 10 compared with calves fed the other treatments. The study average calf starter intake for calves fed Control and EX was greater compared with calves fed BE&EX with calves fed BE being similar and intermediate. Calves fed EX and BE&EX demonstrated greater total d of fecal scour score = 1 (5.4, 5.7, 8.0 and 8.3 d) compared with calves fed Control and BE. Gains in frame measurements of hip height, hip width, withers height, and body length were similar while calves fed BE&EX demonstrated lower heart girth gains (19.2, 18.3, 19.7 and 17.6 cm) during the milk feeding phase (0 - 7 wk) compared with calves fed Control and EX, with calves fed BE being similar and intermediate. It is not known why this study demonstrated an antagonism between BE and EX in growth performance and feed intake but further research is needed to identify the mechanism of action.

Interactions between rumen epithelium-associated microbiota and host immunological and metabolic adaptations in response to different milk replacer feeding intensities in dairy calves

The milk replacer feeding regime in dairy calves has a great impact on metabolic and immunological functioning and affects animal welfare and lifetime performance. The feeding regime influences the rumen microbial composition, and epithelium-associated microbes may interact with the immune system of the host. We examined the correlations between blood leukocyte counts and the rumen epithelium-associated microbiome in dairy calves fed 2 different milk replacer feeding intensities and if these factors related to metabolic traits. Fourteen newborn female dairy calves were allocated to a group receiving either 10% (n = 7) or 20% (n = 7) milk replacer of their body weight (on average 41 kg) and provided ad libitum access to grass hay and concentrate pellets. At 3 weeks of life, all calves were fitted with a rumen cannula. Calves were weaned at 12 weeks of life and received a total mixed ration for ad libitum intake. Pre- (8 to 10 weeks of life) and post-weaning (21 to 23 weeks of life), methane production was measured in respiration chambers, and rumen epithelium and blood were sampled for 16S rRNA sequencing and leukocyte analyses, respectively. Pre-weaning, the reduced milk replacer feeding intensity was accompanied with higher concentrate intake but lower growth performance (P < 0.001), a higher abundance of amylolytic and lower abundance of cellulolytic epimural microbes. The group fed a low milk replacer intensity had also greater portions of monocytes (P = 0.031), CD8+ (P < 0.001), and CD14+ (P = 0.044) leukocytes, suggesting elevated inflammatory conditions. Correlations between CD8+ T cells and rumen methanogens, Ruminococcaceae, and Lachnospiraceae were recorded, but these were not consistent throughout maturation. Post-weaning, differences in feed intake and rumen microbial composition converged among milk replacer groups, while differences in growth performance (P = 0.040) and CD8+ cells (P < 0.001) were still present. In conclusion, a reduced milk replacer feeding intensity in dairy calves compromised growth performance and immunity and this effect persisted in the long-term. Significant correlations between the proportion of leukocytes and distinct epimural microbe taxa indicated an interplay between rumen epimural colonization and immune functioning of the host. However, further research is required addressing this interplay between rumen epimural microbes and immune functioning in dairy calves.

Long-term effects of pre-weaning social housing on response to a social and housing transition in pregnant heifers

Dairy cattle are routinely managed in social groups and subject to various management and social transitions, yet conventional approaches to rearing dairy calves limit social experience during early weeks of life. The objective of this study was to evaluate long-term effects of dairy calf social housing, with calves housed individually or in pairs, on long-term behavioral responses observed in pregnant heifers following social regrouping and introduction to a novel housing environment. Holstein heifers were raised during the milk-feeding period (provided 8 L/d milk replacer) in either individual pens (n = 20 heifers) or paired pens (n = 20 pens; 1 focal heifer/pen) and subsequently identically managed in groups on pasture from 9 weeks of age. At 30 d before expected calving, pregnant heifers were moved from pasture to a free stall barn, which represented introduction to a novel social group and an unfamiliar housing environment. Behavior was continuously recorded from video for 24 h, beginning at 0000 h on the day after introduction, to characterize feeding behavior, locomotor activity, and stall usage, as well as social proximity and competitive behavior surrounding the feed bunk and stall. Stocking density of the free stall barn fluctuated and was categorized as low (≤75%, 100 × animals in pen/available stalls), medium (>75%, 100%), or high (≥100%). Body weights obtained following calving indicated that previously PH heifers were heavier (632.3 vs. 593.4 kg; PH vs. IH), and body weight was included as a covariate in analysis of feeding behavior. Upon introduction to the free stall pen, previously PH heifers spent more time walking (1.9 vs. 1.3 min/h) with no effect of calf social housing on duration of lying time. However, stall use was subject to an interaction between previous housing treatment and stocking density and differed overall between previous housing treatments; previously PH heifers spent less time in the stall, particularly at high stocking density (29.4 vs. 48 min/h), due to shorter (29.6 vs. 95.7 min/visit) but marginally more frequent stall visits. Previously pair-housed heifers were also less likely to be displaced from a stall (44 vs. 85% of heifers replaced; PH vs. IH). Feeding behavior was similarly influenced by previous housing treatment particularly at high stocking density, with previously PH heifers spending more time feeding (8.2 vs. 4.2 min/h) and visiting the feed bunk more frequently (1.5 vs. 0.8 visits/h). These results suggest that preweaning social housing had long-term effects on behavior and ability to adapt to a novel environment which became most apparent under heightened competitive pressure.

Awareness of Plant-based Dairy Alternatives Among the College Students of Anand City, India

This study examines the level of awareness of plant-based dairy alternatives among college students in Anand City. With growing concerns over health, environmental sustainability, and animal welfare, plant-based alternatives to traditional dairy products have gained significant attention. Statistical analysis revealed varying degrees of awareness among respondents, influenced by factors such as dietary preferences, health consciousness, and environmental concerns. A primary survey was carried out with several questions covering general knowledge about " Plant-based Dairy Alternative " items. Available data was analyzed using descriptive statistics. Overall, the survey results showed that respondents understood what Plant-based Dairy Alternative were and the majority of them got aware of social media.