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As a science-driven company, we regularly publish peer-reviewed papers to validate the research we conduct. 

Most recent publications

Dietary protein oscillation: Effects on feed intake, lactation performance, and milk nitrogen efficiency in lactating dairy cows

Ruminants
Limited research with growing ruminants indicates that oscillating (OS) dietary crude protein (CP) concentration may improve nitrogen use efficiency (NUE). Our aim was to determine if a total mixed ration (TMR) based on OS CP (48-h phases of 13.4% and 16.5% CP, respectively) would increase NUE of lactating dairy cows compared with a static CP TMR (ST; 14.9% CP). The experiment was a randomized complete block design with 50 cows [150 ± 61 (mean ± SD) d in milk]. Cows were blocked by parity, days in milk, and milk protein yield. On average, diets were equal in composition over the total experiment. Cows were milked twice daily, and 8 milk samples were collected in each 4-d period. Each 48 h of low-CP (LP) and high-CP (HP) TMR offered to OS cows corresponded to milk collected at milkings 1 to 4 and 5 to 8, respectively. Dry matter intake (mean = 25.5 kg/d for both treatment groups); yields of milk (mean = 31.5 kg/d for both treatment groups), protein, fat, lactose, and fat- and protein-corrected milk (mean = 33.6 kg/d for both treatment groups); and milk concentration of protein, fat, and lactose did not differ between treatments. However, milk urea concentration was higher for OS compared with ST (12.2 vs. 11.3 mg/dL). Body weight, body condition score, NUE, and feed efficiency were unaffected by OS. Apparent total-tract digestibility of dry matter (695 vs. 677 g/kg), organic matter (714 vs. 697 g/kg), CP (624 vs. 594 g/kg), neutral detergent fiber (530 vs. 499 g/kg), and starch (976 vs. 973 g/kg) were higher for OS than for ST cows. Cows in OS responded transiently, and regression analysis of differences within block over time revealed changes in yield of milk (−531 g/d), milk protein (−25.6 g/d), and milk lactose (−16.7 g/d) in LP. Opposite effects were observed for yield of milk (+612 g/d), milk protein (+28.8 g/d), and milk lactose (+28.0 g/d) during HP. Changes in concentrations of milk protein (−0.050%/d), lactose (+0.030%/d), and urea (−3.0 mg/dL per day) during LP, and in milk lactose (−0.024%/d) and urea (+4.3 mg/dL per day) during HP, were observed. Milk yield, lactose yield, and protein yield were lower for OS than ST cows at the last milking of LP and at the first milking of HP. Milk urea concentration did not show such a lag and was lower in the last 2 milkings of LP, and higher in the last 3 milkings of HP, in OS compared with ST cows. Overall, performance and NUE were unaffected by OS treatment, but apparent total-tract digestibility and milk urea concentration increased, and transient effects on milk yield and composition occurred in OS cows.
by R. Rauch on 08.07.2021
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Proteomic Analysis of Liver from Finishing Beef Cattle Supplemented with a Rumen-Protected B-Vitamin Blend and Hydroxy Trace Minerals

Ruminants
Vitamin B and trace minerals are crucial molecular signals involved in many biological pathways; however, their bioavailability is compromised in high-producing ruminant animals. So far, studies have mainly focused on the effects of these micronutrients on animal performance, but their use in a rumen-protected form and their impact on liver metabolism in finishing beef cattle is poorly known. We used a shotgun proteomic approach combined with biological network analyses to assess the effects of a rumen-protected B-vitamin blend, as well as those of hydroxy trace minerals, on the hepatic proteome. A total of 20 non-castrated Nellore males with 353 ± 43 kg of initial body weight were randomly assigned to one of the following treatments: CTRL—inorganic trace minerals without supplementation of a protected vitamin B blend, or SUP—supplementation of hydroxy trace minerals and a protected vitamin B blend. All animals were fed the same amount of the experimental diet for 106 days, and liver biopsies were performed at the end of the experimental period. Supplemented animals showed 37 up-regulated proteins (p < 0.10), and the enrichment analysis revealed that these proteins were involved in protein folding (p = 0.04), mitochondrial respiratory chain complex I (p = 0.01) and IV (p = 0.01), chaperonin-containing T-complex 2 (p = 0.01), glutathione metabolism (p < 0.01), and other aspects linked to oxidative-stress responses. These results indicate that rumen-protected vitamin B and hydroxy trace mineral supplementation during the finishing phase alters the abundance of proteins associated with the electron transport chain and other oxidation–reduction pathways, boosting the production of reactive oxygen species, which appear to modulate proteins linked to oxidative-damage responses to maintain cellular homeostasis.
28.06.2021
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Effect of immunized egg proteins on the performance and neonatal diarrhoea incidence in newborn calves

Ruminants
The aim of this study was to assess the effects of feeding immunized egg proteins (IEP) on the health and performance of newborn dairy calves. Sixty‐four Holstein calves, both male and female, were divided over two treatments. Calves either received IEP or a placebo (PCB) in their colostrum and calf milk replacer (CMR) for the first 14 days of their life. Until day 49, CMR was offered at 15% of birth weight (BW), at 10% on days 49–57 and at 5% on days 57–63. In addition, calves received starter concentrate, chopped straw and water from 3 days old until 70 days old at the end of study. Individual CMR and concentrate intake were measured daily whilst BW was recorded weekly. Visual faecal scoring and health observations were conducted daily. Faecal samples were collected weekly up to 4 weeks and during the first 4 days of scouring to screen for presence of Cryptosporidium parvum, rotavirus, coronavirus, E. coli and Salmonella. Results indicated that feeding IEP increased BW (p < .05) at 42 and 56 days old, and BW also tended (p = .06) to be higher after weaning at 63–70 days old compared to the PCB group. When analysed using a repeated measures model, compared to feeding PCB, feeding IEP increased total concentrate consumption (p = .001) by 3.6kg/calf. Over the entire study, daily water intake was higher (p = .002) for the IEP group when compared with the PCB group. In the IEP group, 12 calves were scored as scouring whereas there were 14 calves in the PCB group. There were no significant differences between treatments in faecal pathogen load of neither healthy nor scouring calves. In conclusion, supplementing IEP during the first 14 days of calf life improved the performance of newborn calves. Further work is warranted to understand the mode of action of IEP in calves.
by S. J. A. van Kuijk on 18.01.2021
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Evaluation of predicted ration nutritional values by NRC (2001) and INRA (2018) feed evaluation systems, and implications for the prediction of milk response

Ruminants
Net energy and protein systems (hereafter called feed evaluation systems) offer the possibility to formulate rations by matching feed values (e.g., net energy and metabolizable protein) with animal requirements. The accuracy and precision of this approach relies heavily on the quantification of various animal digestive and metabolic responses to dietary changes. Therefore, the aims of the current study were, first, to evaluate the predicted responses to dietary changes of total-tract digestibility (including organic matter, crude protein, and neutral detergent fiber) and nitrogen (N) flows at the duodenum (including microbial N and undigested feed N together with endogenous N) against measurements from published studies by 2 different feed evaluation systems. These feed evaluation systems were the recently updated Institut National de la Recherche Agronomique (INRA, 2018) and the older, yet widely used, National Research Council (NRC, 2001) system. The second objective was to estimate the accuracy and precision of predicting milk yield responses based on values of net energy (NEL) and metabolizable protein (MP) supply predicted by the 2 feed evaluation systems. For this, published studies, with experimentally induced changes in either NEL or MP content, were used to calibrate the relationship of NEL and MP supply, with milk component yields. Based on the slope, root mean square prediction error, and concordance correlation coefficient (CCC), the results obtained show that total nonammonia nitrogen flow at the duodenum was predicted with similar accuracy and precision, but considerably better prediction was achieved when the INRA model was used to predict organic matter and neutral detergent fiber digestibility responses. The average NEL and MP content predicted by both models was similar, but NEL and MP content of individual diets differed substantially between both models as indicated by determination coefficients of 0.45 (NEL content) and 0.50 (MP content). Despite these differences, this work shows that when response equations are calibrated with NEL and MP values either from the INRA model or from the NRC model, the accuracy and precision (slope, root mean square prediction error, and CCC) of the predicted milk component yields responses is similar between the models. The lowest accuracy and precision were observed for milk fat yield response, with CCC values in the range of 0.37 to 0.40, compared with milk lactose and protein yields responses for which CCC values were in the range of 0.75 to 0.81.
by J. B. Daniel on 06.10.2020
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Targeting the Hindgut to Improve Health and Performance in Cattle

Ruminants
An adequate gastrointestinal barrier function is essential to preserve animal health and well-being. Suboptimal gut health results in the translocation of contents from the gastrointestinal lumen across the epithelium, inducing local and systemic inflammatory responses. Inflammation is characterized by high energetic and nutrient requirements, which diverts resources away from production. Further, barrier function defects and inflammation have been both associated with several metabolic diseases in dairy cattle and liver abscesses in feedlots. The gastrointestinal tract is sensitive to several factors intrinsic to the productive cycles of dairy and beef cattle. Among them, high grain diets, commonly fed to support lactation and growth, are potentially detrimental for rumen health due to their increased fermentability, representing the main risk factor for the development of acidosis. Furthermore, the increase in dietary starch associated with such rations frequently results in an increase in the bypass fraction reaching distal sections of the intestine. The effects of high grain diets in the hindgut are comparable to those in the rumen and, thus, hindgut acidosis likely plays a role in grain overload syndrome. However, the relative contribution of the hindgut to this syndrome remains unknown. Nutritional strategies designed to support hindgut health might represent an opportunity to sustain health and performance in bovines.
by M. V. Sanz-Fernandez on 05.10.2020
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Technical note: Is fecal consistency scoring an accurate measure of fecal dry matter in dairy calves?

Ruminants
The objective of this cross-sectional study was to evaluate the accuracy of fecal consistency scoring as a measure of fecal dry matter (DM) in dairy calves. This study was conducted at a commercial grain-fed veal facility in southwestern Ontario. A total of 160 calves arrived at the facility in 2 groups of 80 calves each. Calves were fed milk replacer twice daily at 0700 and 1700 h and had ad libitum access from arrival onward to water through nipple drinkers and starter through a shared trough. Fecal consistency scores were evaluated once daily in the first 28 d after arrival before milk feeding. The fecal consistency scoring was conducted using a 4-level scoring scale: 0 = normal (firm but not hard); 1 = soft (does not hold form, piles but spreads slightly); 2 = runny (spreads readily); and 3 = watery (liquid consistency, splatters). Fecal samples were collected from all calves via rectal palpation on d 1, 7, 14, and 21 at 0900 h for determination of fecal DM. Mixed repeated measures linear regression models were built to assess the accuracy of fecal consistency scoring in predicting fecal DM. Over 4 selected time points (d 1, 7, 14, and 21) the 160 calves were observed, 382 (61.6%) had a fecal consistency score of 0, 121 (19.5%) had a score of 1, 85 (13.7%) had a score of 2, and 32 (5.2%) had a score of 3. A fecal score of 0 had a fecal DM of 25.1 ± 8.4%, whereas a fecal score of 1 had a DM of 21.8 ± 8.2%. With respect to calves that had a fecal score of 2 or 3, their fecal DM was 16.0 ± 11.1% and 10.7 ± 6.9%, respectively. In evaluating the pairwise comparisons generated in the repeated measures model that controlled for day of sampling, a fecal score of 0 had a 3.2%, 8.1%, and 12.0% higher fecal DM, respectively, when compared with those that had a fecal score of 1, 2, and 3. In addition, calves with a fecal score of 1 had a 5.0% and 8.8% higher fecal DM than calves with a fecal score of 2 and 3, respectively. Finally, calves with a fecal score of 2 had a 3.8% higher fecal DM than those with a fecal score of 3. This study confirms that using observational fecal consistency scoring can accurately predict diarrhea or a decline in fecal DM.
by D. L. Renaud on 17.09.2020
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Effect of a Commercial Bentonite Clay (Smectite Clay) on Dairy Cows Fed Aflatoxin-Contaminated Feed

Ruminants
We evaluated the impact of dietary supplementation with a commercially available smectite clay (TOXO® MX, Trouw Nutrition, Amersfoort, The Netherlands), that binds to aflatoxins (AFs), on the performance and health status of multiparous lactating Holstein dairy cows that received dietary AFB1 (the main AF). The carry-over of AFB1 was determined by measuring AFM1 (the main metabolite) in dairy milk. Performance values, blood markers, and liver inflammatory markers were also measured. Nine multiparous mid-lactation Holstein cows (parity: 2.67 ± 0.86; days in milk: 91 ± 15 days; milk yield: 40.4 ± 2.7 kg/cow/day) were assigned to one of three treatments in a 3 periods × 3 treatments Latin square design (n = 3). In particular, three cows each received the CTR-0 diet (total mixed ration (TMR) with normal corn meals), the CTR-AFLA diet (CTR-0 diet with 17.53 ± 6.55 µg/kg DM AFBI), or the TRT diet (CTR-AFLA diet with 100 ± 1 g/cow/day of smectite clay). The AFB1 level was 0.63 ± 0.50 µg/kg DM in the CTR-0 diet, 2.28 ± 1.42 µg/kg DM in the CTR-AFLA diet, and 2.13 ± 1.11 µg/kg DM in the TRT diet. The experiment consisted of an adaptation period (21 days) and three 17-day experimental periods, each consisting of a 10-day intoxication period and 7-day clearance period. Data were analyzed using the MIXED procedure of SAS (SAS Inst. Inc., Cary, NC, USA) with or without repeated measurements. Overall, the addition of AFB1 reduced the DM intake, but the groups had no significant differences in milk yields. The highest feed efficiency was in the TRT group. Measurement of AFM1 in milk indicated a “plateau” period, from day 4 to day 10 of the intoxication period, when the AFM1 level exceeded the guidelines of the European Union. The commercial smectite clay reduced milk AFM1 concentration by 64.8% and reduced the carry-over by 47.0%. The CTR-0 and TRT groups had similar carry-over levels of AFM1, although the absolute concentrations differed. The groups had no significant differences in plasma biomarkers. These results indicate that the commercially available smectite clay tested here was effective in adsorbing AFs in the gastro-intestinal tracts of cows, thus reducing the excretion of AFM1 into dairy milk.
by A. Gallo on 22.08.2020
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Total-tract digestibility and milk productivity of dairy cows as affected by trace mineral sources

Ruminants
The chemical characteristics associated with different sources of Cu, Zn, and Mn such as sulfate, hydroxychloride, or organic chelate may affect the interaction between the metals and other components present within the gut of a ruminant (i.e., microorganisms and nutrients). The present study aimed to evaluate the effect of different supplemental trace mineral strategies on apparent total-tract digestibility, rumen fermentation, and dairy productivity. Using 52 Holstein cows in a replicated 4 × 4 Latin square design with periods of 21 d, 4 treatments differing in their sources of Cu, Zn, and Mn were tested: sulfate form, hydroxychloride form, a mix of sulfate and organic chelate forms (70 and 30%, respectively), and a mix of hydroxychloride and organic chelate forms (70 and 30%, respectively). Treatments were formulated to provide 15, 40, and 20 mg of supplemental Cu, Zn, and Mn, respectively, per kilogram of dry matter. This level of supplementation, together with the basal level present in forages and feed ingredients, resulted in a total average supply of 19, 79, and 84 mg of Cu, Zn, and Mn, respectively, per kilogram of dry matter. Cows had ad libitum access to a total mixed ration, which provided 15.3% of crude protein, 21.7% of starch, and 35.3% of neutral detergent fiber (NDF). Data were summarized by period with trace minerals and period as fixed effects and the repeated cow as random effect using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC). Apparent total-tract NDF and crude protein digestibility was reduced (−0.8% and −1.0%, respectively) when organic chelate trace minerals were fed, whereas apparent total-tract NDF digestibility was improved (+0.8%) when sulfate trace minerals were replaced by hydroxychloride trace minerals. Cows supplemented with the hydroxychloride source had lower ruminal butyric acid concentration compared with cows fed sulfate trace minerals (13.3 vs. 14.6%). In addition, fat- and protein-corrected milk and milk fat yields were improved (+1.0 kg/d and +51 g/d, respectively) in multiparous cows when trace minerals were supplemented as hydroxychloride compared with sulfate. These effects were not observed in primiparous cows. These results confirm that trace mineral sources affect apparent total-tract digestibility and indicate that milk productivity may also be affected. Key words
by J. B. Daniel on 18.08.2020
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Tonicity of oral rehydration solutions affects water, mineral and acid–base balance in calves with naturally occurring diarrhoea

Ruminants
Recommendations for composition of oral rehydration solutions (ORS) for calves, particularly concerning Na+, glucose, and their combined effect on tonicity, are not in line with guidelines for humans. Thus, this study aimed to determine the effect of ORS tonicity on water, mineral and acid–base balance. Seventy‐two calves were selected based on the severity of dehydration and blood base excess (BE) on day 0. Five calves that did not develop diarrhoea were removed post‐inclusion from the study. Calves were allocated to blocks of four animals based on blood BE on day 1. Within each block, calves were randomly assigned to one of four treatments: (a) hypotonic ORS with low Na+ and lactose (HYPO); (b) isotonic ORS with low Na+and glucose (ISO); (c) hypertonic ORS with high Na+ and glucose (HYPER); and (d) control consisting of warm water including 5 g/L of whey powder (CON). Treatments were administered twice daily over a 3‐day period, in which calves were offered 2.0 L of treatment at 1300 and 2100 hr. Calves were fed 2.5 L of milk replacer at 0700 and 1630 hr from day 1 to 3 and 3.0 L from day 4 to 5, and had access to water. Calves were monitored for 5 days in which measurements included intakes, BW, blood sampling and collection of faeces on day 1 and urine from day 1 to 3. All ORS treatments maintained normal serum Na+, whereas CON did not. Calves in the HYPER group had lower blood pH and greater faecal Na+ losses than HYPO and ISO. Plasma expansion relative to baseline was higher in low tonicity ORS (+4.8%) when compared with CON (+1.0%). Urine osmolality was 30% higher in HYPER calves. In this experiment, low tonicity ORS were more effective at restoring water, mineral and acid–base balance than the hypertonic ORS.
by J. N. Wilms on 03.07.2020
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