Milk Protein Content Research Articles

Performance of dairy cows offered either zero-grazed grass or grass silage prepared from the same sward

Daily harvesting of fresh grass for housed livestock when its nutritive value is high (Zero-grazing) is a labour-intensive process which requires a consistent supply of grass at the optimum growth stage. An alternative approach which may save on labour and require less time spent on grassland management each day, involves harvesting and ensiling herbage on a number of occasions (every 4 weeks approximately) during the growing season when it is at the same nutritive value as herbage used for zero-grazing. This study examined the impact of these two approaches to dairy cow performance. Thirty-six mid-lactation Holstein-Friesian dairy cows were offered either zero-grazed fresh grass (ZG), or grass silage (SIL) prepared from the same sward harvested at a similar growth stage, over a single season. Fresh grass was harvested daily and offered to ZG cows for a 12-week period. During this period, the same sward was harvested once weekly and ensiled in round bales. Following a five-week ensilage period, the silage was offered to cows on SIL for a 12-week period. All cows were also offered 8.0 kg concentrate per day. Zero-grazed grass and grass silage had a mean metabolisable energy content of 11.0 and 11.3 MJ/kg DM, respectively. Mean forage DM intake (DMI) and total DMI were greater for cows on ZG (P < 0.001) compared to SIL, with intakes during weeks 8–12 of the experiment lower with SIL compared to ZG (P < 0.001). Cows on ZG had a higher milk yield, milk protein concentration, milk fat plus protein yield and energy-corrected milk (ECM) yield (P < 0.001) than cows on SIL. With the exception of milk yield (where the difference was primarily observed during weeks 8–12 of lactation), these differences were observed most weeks during the study period. Milk fat concentration was unaffected by treatment (P > 0.05). Milk of cows on ZG had higher concentrations of total monounsaturated fatty acids (P < 0.001), total polyunsaturated fatty acids (PUFAs, P < 0.001) but lower concentrations of saturated fatty acids (SFAs, P < 0.001) compared to cows on SIL. Diet had no effect on cow BW or condition score. This study has shown that when harvested from the same sward, milk yield and ECM yield were improved when cows were offered zero-grazed grass compared to grass silage. This difference in performance was likely due to the lower forage intake observed with the grass silage-based diet.

Beneficial effects of antioxidant micronutrients during peri-parturient period on reproductive, udder and body performance of crossbred cows

BackgroundThe critical and stressful peri‑parturient period in the life of a dairy animal creates challenges for dairy owners to keep the animal in the optimum condition of health and hence production. Micronutrients with antioxidant properties help in reducing oxidative stress. A combination of antioxidant micro-nutrients was investigated in the ration of crossbred cows with a hypothesis to eliminate the negative effects of oxidative stress during the stressful peri‑parturient period. MethodsTwenty healthy advanced pregnant crossbred cows reared under similar conditions of feeding with no history of mastitis during previous lactation were selected randomly for the study. Cows were equally distributed randomly into two groups keeping the parity, body condition score, and last record of lactation comparable. Cows were fed the same basal ration with the inclusion of a combination of antioxidant micronutrients (having trace elements copper and zinc with vitamins A and E as per the standard recommendations for cows for the prevention of mastitis) in the diet of the treated group daily, while another group served as control. ResultsThe overall average total (5 %) and fat-corrected milk yield (10 %) remained high in the treatment group. The fat, protein, and lactose content of milk, as well as milk pH, remained statistically comparable (P > 0.05) between the two groups. The overall mean values of milk solid-not-fat remained significantly high (P = 0.04) with a reduced value of the somatic cell count (P = 0.03) in the treatment group indicating the advantage of the antioxidant micronutrients inclusion in the diet. The incidences of mastitis reported in the treatment group were only 14 % (8 Vs 56) as compared to the control group across the entire study period. Higher (P = 0.023) body condition scores in the treatment group cows during the prepartum period lead to lower (0 Vs 40 %) incidences of peri‑parturient reproductive disorders. ConclusionsIt may be concluded that supplementation of antioxidant micronutrients in the dairy cow's ration helps in preventing the adverse effect of oxidative stress during the stressful transition stage and is hence capable to reduce the incidences of mastitis and peri‑parturient reproductive disorders in addition to an enhancement in solid-not-fat content of the milk.

Predicted essential fatty acid intakes for a group of dairy cows also apply at individual animal level

The ruminant requirements for essential fatty acids (EFAs), particularly linoleic acid (LA) and alpha-linolenic acid (ALA), have not been fully determined, although evidence suggests that an adequate supply of polyunsaturated fatty acids (FAs) could improve immunity and reproduction in transition cows. In previous studies, we predicted EFA intake for a group of cows based on animal characteristics and milk EFA secretions. However, to support precision livestock feeding, we need to match the nutrient requirements and intakes of each cow as closely as possible. Our group-level predictions may not be accurate enough to estimate the EFA intake of an individual cow, due to inter-individual variations in EFA digestion and metabolism related to differences in feed intake, intake patterns, and the composition and functioning of the rumen microbiota. To address this issue, here we set out to establish specific equations that predict EFA intake for an individual cow based on the difference (i.e. the residuals) between observed EFA intake and the predicted EFA intake based on our group-level equations. We studied a database of individual dairy cows (26 experiments; 503 datapoints from three research teams) and we predicted the residuals from (1) dietary and animal-related factors (i.e. full predictions) and (2) animal-related factors only (i.e. field predictions), which are considered more field-amenable. The variance of predicted LA and log ALA intake was explained to 68% by observed LA intake and 66% by observed log ALA intake, respectively. The residuals of LA intake were predicted by dietary ALA content, total FA intake, BW, milk yield and fat content in full predictions, and by BW, feeding level, milk yield and fat content, and sum of milk C4:0 to C14:0 FA in field predictions. The log residuals of ALA intake were predicted by dietary NDF and total FA contents, NDF intake, BW, milk protein, LA and ALA contents, and fat yield in full predictions, and by BW, DM intake, milk LA and ALA contents, and fat yield in field predictions. The field predictions showed a moderate loss of accuracy compared to full predictions based on RMSE of prediction (from 38 to 54 g/d for LA and from 0.090 to 0.12 log (g/d) for ALA). This work is the first to predict the EFA intake of an individual cow based on previously established group-level predictions of EFA intake adjusted for dietary and animal-related factors.

Analysis of reproduction success, growth and milk trajectories and response to nutritional challenge in two Alpine goat lines selected on divergent longevity

This study aims to investigate whether the variation in reproduction success, growth, and milk trajectories is associated with different adaptive strategies in the short term (response to an acute nutritional challenge), using two Alpine goat lines. A total of 382 Alpine goats (179 low longevity (low_LGV) and 203 high longevity (high_LGV)), selected for divergent functional longevity from a commercial population, were monitored for 4 years and recorded for BW, reproduction and milking performance. Every year, an average of fifty primiparous goats were exposed to a 2-d nutritional challenge in early lactation. A polynomial model was used to analyse the lifetime trajectory of lactation and BW. A piecewise model was used to analyse the individual milk yield and responses of milk components to the nutritional challenges. The statistical analysis revealed that the two lines had a similar performance for total milk yield in the first lactation, BW at birth and at first kidding, litter size and weight, kidding interval and interval from the first insemination to conception. BW trajectories revealed that low_LGV goats had a greater BW in pregnancy but then lost more weight in early lactation compared to high_LGV goats, which showed a greater BW after kidding. Milk trajectories showed that the high_LGV goats had a higher initial milk yield, an earlier but less marked lactation peak and more persistency in milk production in late lactation than low_LGV goats. Except for milk protein content, quite similar response and recovery profiles of milk yield and milk fat content were observed during the challenge for both lines. The response to the challenge was positively correlated to the initial level of milk production in early lactation but negatively correlated with milk production decline after the peak. This finding suggests that the low_LGV goats were more adapted to allocate resources to meet an expected physiological change such as gestation and lactation. However, high_LGV goats allocate more than low_LGV goats for structural mass and may better cope with an unexpected environmental change such as nutritional deficit.

Risk factors of high somatic cell count and differential somatic cells in early lactation associated with selective dry cow therapy.

The routine use of intramammary antimicrobial products in all dairy cows at the beginning of the dry period is no longer allowed in European Union (EU) countries due to the new Regulation (EU) 2019/6 to reduce antimicrobial resistance. This study investigated the application of a selective dry cow therapy scheme and the risk factors of high individual milk somatic cell count (SCC) and individual neutrophil count in early lactation, as a response to the application of a selective dry cow therapy (SDCT) protocol. The study was carried out on three commercial farms, and a total of 243 lactating cows were monitored at the end of lactation and at the beginning of the next one, 91 of which were dried off without the use of antimicrobials (NoT) based on milk SCC, differential somatic cell count (DSCC), and the response of Vetscan DC-Q milk analyser, using a secret algorithm. The remaining 152 cows received antimicrobials (T). After calving, similar means were observed between the two treatment groups for SCC (4.8 vs 4.9 log10 cells/ml for T and NoT, respectively, P=0.5) and total milk leucocyte count (TLC) (5 vs 5.1 log10 cells/ml for T and NoT, respectively, P=0.7) in milk. However, the use of antimicrobials led to a lower DSCC (58 vs 64% for T and NoT, respectively, P=0.01) and lower percentage of neutrophils (59 vs 64% for T and NoT, respectively, P=0.05), although the levels of DSCC and percentage of neutrophils in cows dried off without antimicrobials remained lower than the risk threshold suggested by the international literature. A logistic regression was computed after the application of selective dry cow therapy to identify risk factors of high milk SCC (≥100000 cells/mL) at the beginning of lactation. Increased milk SCC after calving was related to high SCC at the end of lactation and abandonment of antimicrobial therapy at dry-off. Moreover, the length of the dry period, milk protein content, and flank cleanliness in the last test day before dry-off were other factors in the logistic regression. Neutrophil counts at the beginning of the next lactation were affected by the same factors that influenced SCC, together with milk production, TLC, and macrophages on the last test day. The results obtained in these studied farms showed that selective dry cow therapy may be applied without adversely affecting the next lactation.

Effect of feeding Yucca schidigera extract and a live yeast on the rumen microbiome and performance of dairy cows fed a diet excess in rumen degradable nitrogen.

Nitrogen (N) loss from livestock agriculture via ammonia and nitrous oxide can reduce feed efficiency, production and negatively affect the environment. One option to reduce N loss is to add dietary supplements such as Yucca schidigera extract which has ammonia-binding properties and contains antimicrobial steroidal saponins, or Saccharomyces cerevisiae yeast, which can stabilise rumen pH and promote fibre degradation, increasing microbial growth and demand for degradable N. To determine the effect of Yucca schidigera extract when fed alone or in combination with a live yeast on the performance, rumen metabolism, microbiome and N balance, six rumen cannulated dairy cows were fed a mixed ration (C), mixed ration with Y. schidigera extract (De-Odorase®, Alltech®; 5g/cow/day; D), or mixed ration with Y. schidigera extract (5g/day) and Saccharomyces cerevisiae (Yea-Sacc®, Alltech®, 1g/cow per day; DY), in a 3×3 Latin rectangle design study with three periods of 49-day duration. Digesta samples were collected via the ruminal cannula during the final week of each period and separated into liquid (LPD) and solid (SPD) phases for microbiome analysis using 16S rRNA amplicon sequencing. DM intake was 0.8kg/d lower (P<0.05) in cows fed DY than C or D, with milk protein concentration 1.7g/kg higher in C than D or DY. There was a beta diversity (Bray Curtis) clustering of the LPD in cows fed D or DY compared to C (P<0.05), driven by an increase in Prevotella ruminicola-related operational taxonomic units (OTUs), and a decrease in P. brevis and P. bryantii OTUs. A methanogen OTU, Methanobrevibacter olleyae, was decreased in cows fed D or DY and an unclassified species of Gammaproteobacteria was increased in DY (LDA>2.0, P<0.05) compared to C. Rumen pH, ammonia and total VFA concentration were not affected by treatment (P>0.05) but the concentration of propionate and iso-butyrate were lower at 1700 and 2000h in cows fed DY compared to C (P <0.05). Measurements of N balance were unaffected by supplementation with D or DY, and there was no effect of treatment on slurry pH. In conclusion, supplementing with an extract of Yucca schidigera either alone or in combination with a live yeast had only a small effect on performance, with Yucca schidigera altering species associated with carbohydrate and protein metabolism, and reduced Methanobrevibacter olleyae which is involved in methanogenesis.

Interaction between gestational plane of nutrition and lactation diet composition on lactation performance of Alpine goats of different parities

A study was conducted with 48 multiparous and 31 primiparous Alpine goats to determine the effects of different nutritional planes during gestation and lactation on feed intake, body weight, body condition score and mass index, blood constituent concentrations, and milk yield and composition. Two gestation supplement treatments (GS; Moderate versus High) were imposed for approximately 5.5 months and two lactation diets (LD; Moderate vs. High) within each GS were fed for 16 wk. The Moderate GS (14.2% crude protein; CP) was given at 1.125% body weight (BW; dry matter basis) and the High GS (16.2% CP) was consumed ad libitum, with alfalfa hay available free-choice to all animals. Moderate and High LD contained 16.0 and 16.9% CP and 34.7 and 30.4% neutral detergent fiber, respectively. Body weight (77.5 vs. 72.0 kg) and body condition score (BCS; 3.22 vs. 3.04) at 11 days before kidding were greater (P < 0.05) for High versus Moderate GS, but BW at kidding (62.6 and 64.9 kg; SEM = 1.32) and 3 days later (60.9 and 63.6 kg for Moderate and High GS, respectively; SEM = 1.32) was similar. Litter size (1.9 and 2.4; SEM = 0.59), kid birth weight (3.72 and 3.59 kg; SEM = 0.097), and litter weight (6.55 and 7.13 kg for Moderate and High GS, respectively; SEM = 0.316) were similar between GS diets. However, kid birth weight (3.44 and 3.87 kg; SEM = 0.096) and litter weight (6.23 and 7.46 kg; SEM = 0.364) were greater (P < 0.05) for multiparous versus primiparous goats. Dry matter intake during lactation was greater for Moderate than for High GS (P ≤ 0.051) in kg/day, % BW, and g/kg BW0.75. However, milk fat (3.81, 4.14, 3.85, and 3.77%; SEM = 0.132) and protein concentrations (2.49, 2.50, 2.47, and 2.49%; SEM = 0.047), and raw (2.22, 2.59, 2.39, and 2.45 kg; SEM = 0.173) and energy yields of milk (6.02, 7.42, 6.51, and 6.63 MJ/day for Moderate GS-Moderate LD, Moderate GS-High LD, High GS-Moderate LD, and High GS-High LD, respectively; SEM = 0.453) were not affected by GS, LD, or their interaction. Dry matter intake, milk and its component yields, and heat energy (MJ/day) were higher (P < 0.05) for does than for doelings, but BCS and milk protein and fat concentrations were lower (P < 0.05) for does. Blood nonesterified fatty acid concentration was not affected by any diets, but there was interaction (P < 0.05) between GS and LD for betahydroxybutyric acid concentration. In conclusion, minor to moderate magnitudes of difference in nutritional planes during gestation and lactation had little effect on reproductive and lactation performance, reflecting the considerable capacity of lactating dairy goats for compensatory changes such as feed intake and tissue mobilization and accretion.

Effects of non-genetic factors on milk yield and chemical composition of milk from Holstein-Friesian cows

Background: It is necessary to determine the extent and direction of environmental factors to accurately assess cow performance in terms of milk yield and milk components. Although many studies have explored environmental factors affecting milk yield, there is not enough information about the effects and direction of environmental factors on milk composition. Objective: To determine the effects of non-genetic factors, such as calving season, lactation number, lactation stage, animal age, and herd size on milk yield, chemical composition of raw milk, and Somatic Cell Count (SCC) in Holstein-Friesian cows. Methods: Data were obtained from 15,354 raw milk samples of 5,118 Holstein-Friesian cows at 276 dairy farms in Türkiye. The data analysis was performed using the General Linear Model (GLM) feature of the SPSS statistics program. Results: Mean fat (F), protein (P), dry matter (DM), lactose (L), urea (U), and Log10SCC values of milk were 3.74 ± 0.01, 3.19 ± 0.01, 11.36 ± 0.03, 4.32 ± 0.01%, 21.57 ± 0.28 mg/dL, and 5.244 ± 0.01 cells/mL, respectively. Peak milk yield (PMY), lactation milk yield (LMY), 305-day milk yield (305-d MY), and SCC values were 33.7 ± 0.13, 8,538.33 ± 89.64 kg, 6,479.42 ± 168.96 kg, and 224,164.34 ± 4,402.79 cells/mL, respectively. Conclusion: Dairy farms in Türkiye should improve protein, dry matter, and urea contents in milk and investigate in detail the relationship between raw milk urea, subclinical mastitis, and reproductive features.

Effect of Different Feeding Methods on Milk Production and Composition of Lactating Punganur Cows

The present experiment was conducted during January–August, 2021 at Livestock Research Station, Palamaner, Chittoor, Andhra Pradesh, India to study the effect of different feeding methods on production performance in lactating Punganur cows. A lactation study of 90 days duration was conducted on 16 lactating Punganur cows which were distributed (CRD) into four treatment groups comprising of 4 animals each. Animals of Control group were maintained as per the feeding practice followed by the farmers rearing Punganur cows in Chittoor district (Hedge lucerne, Paddy straw and Concentrate mixture), T2 group fed with Super Napier grass Paddy straw and Concentrate mixture, T3 group fed with Paddy straw, concentrate mixture and UMMB and T4 group fed with TMR. The average FCM yield (kg d-1) was highest (p&lt;0.05) in T4 followed by T3 or T2 and lowest in T1. The Protein and lactose content (%) of milk was highest (p&lt;0.05) in T4 and lowest in T3, while Fat and SNF (%) remained unaltered. The efficiency of milk production (kg/kg FCM) of DMI and TDNI lowest (p&lt;0.05) in T4, While CPI and DCPI lower (p&lt;0.05) in T4 or T3 as compared to T2 or T1. The cost economics of milk production indicated that the feed cost (`) per kg FCM yield was lowest (p&lt;0.05) in T3. The study concluded that the feed conversion efficiency in terms of DM, CP and Gross energy was highest for TMR group, while cost economics of milk production was better in Paddy straw, concentrate mixture, UMMB and TMR group.

Polymorphism of the &lt;i&gt;Kappa Casein&lt;/i&gt; gene and milk production in cows resulting from crossbreeding with holstein or montbeliarde in the peri-urban area of Bamako

The objective of this contribution is to study the polymorphism of the kappa casein gene in crossbred cows in the peri-urban area of Bamako. Fifty (50) cows, including 22 Montbeliarde crosses and 28 Holstein crosses, were subjected to descriptive analysis comparing average milk production and milk fat and protein percentages and genetic analysis of the kappa-casein gene and its interaction with the crossbred types or breed. The results showed 2 types of crosses for each breed, ½ and ¾ exotic blood. The average daily milk production was 8.2±0.46 kg/d for the Holstein crosses and 7.2±0.73 kg/d for the Montbeliarde crosses with a significant difference. No significant differences were observed for the fat and protein content between Holstein crosses (3.56 ± 0.14% and 3.68±0.02%) and Montbeliarde crosses (3.79 ± 0.10% and 3.74±0.02%). Genetic analysis revealed three genotypes of kappa casein (AA, AB and BB). The AA genotype (0.5) was the most frequent followed by AB (0.41) and BB (0.09). A close link was observed between milk production and the polymorphisms of the kappa casein gene. Individuals with the AB genotype had the highest daily milk production followed by individuals with the AA genotype and those with the BB genotype with respective mean values of 8.6±0.64 kg/d; 7.3±0.56 kg/d and 6.6±1.58 kg/d. Individuals of the BB genotype presented a higher fat content (4.0±0.08%) than that of the other genotypes. The mean milk protein content varied little among the genotypes. These results will contribute to the strengthening of knowledge on the genetic effects of kappa casein polymorphisms on milk production performance and milk composition of crossbred cows in Mali.

Effects of 2 gradual debonding strategies on machine milk yield, flow, and composition in a cow-driven cow-calf contact system

This controlled study compared the effects of 2 different gradual debonding strategies on machine milk yield, flow, and composition in a cow-driven cow-calf contact (CCC) system with automatic milking. Cows had 24 h/d access to their calves during the first weeks of lactation. In the long debonding (LDB) treatment (n = 16), a gradual reduction of cows' access to their calves was initiated 4 wk after calving over a total period of 28 d; first to 12 h/d (14 d), and then to 6 h/d (14 d). In the short debonding (SDB) treatment (n = 14), gradual reduction was initiated 6.5 wk after calving over a total period of 10 d; first to 12 h/d (5 d), and then to 6 h/d (5 d). From 6 h/d, access was finally reduced to 0 h/d for 7 d for both treatments. Machine milk yield, somatic cell count, and peak and average milk flow were automatically registered at milking. During the 9-wk study period, composite samples were analyzed for milk composition. Data were analyzed with linear mixed effect models. Results showed that machine milk yield during 24 h/d access varied between cows (range 1.2-49.9 kg/d, average ± standard deviation 13.2 ± 7.82 kg/d). The LDB cows had a higher daily machine milk yield than SDB cows at the end of and after access reduction was completed (+5.0 ± 1.63 and +5.1 ± 1.55 kg during the last 5 d of 6 h/d access, and 0 h/d access, respectively). Somatic cell count was on a healthy level, with no difference between treatments. Milk fat content increased with reduction in access, regardless of treatment. Short debonding cows tended to show higher milk protein content and lower milk lactose content than cows with a longer debonding. This study has shown that a longer debonding initiated earlier may give a higher milk yield in the short term. The variation in machine milk yield may indicate differences in milk ejection, suckling, and visiting patterns and preferences among cows.

How animal milk and plant-based alternatives diverge in terms of fatty acid, amino acid, and mineral composition

The decline in fresh milk in the Western world has in part been substituted by an increased consumption of plant-based beverages (PBB). These are often marketed as healthy and sustainable alternatives to milk and dairy foodstuff, although studies have suggested PBB to be of lower nutrient quality. The current study considered different brands of almond-, oat-, rice-, coconut- and soya-based beverages for a comparative analysis and found that they indeed presented lower contents of total protein, lipids, amino acids, and minerals than cow and goat milk. The only exception was given by soya-based beverages which approximated the protein content (3.47% vs. 3.42 and 3.25% in cow and goat milk, respectively) and amino acid composition of animal milk, and also demonstrated high mineral content. The natural presence of phyto-compounds in PBB characterised as antinutrients and their potential to exacerbate the issue of low nutrient quality by lowering bioavailability have been discussed.

Changes in Mature Human Milk Macronutrient Composition over 45 years in an Urban Population in Indonesia.

With improvement in a population's welfare, its food consumption patterns may change, including those of nursing mothers. This, in turn, could influence their human milk composition. To investigate the secular trend in macronutrient composition of mature human milk from mothers of healthy, full-term infants in urban populations in Indonesia from 1974 and 2019. We compared the macronutrient composition of mature human milk of healthy full-term infants from 1974 and 2019. The data from 2019 used the Human Milk Analyzer MIRIS to quantify the milk's carbohydrate, fat, and protein content, while the historical data used methods available at that time, that is, methods described by Benedict, Gerber and Kjeldahl, respectively. There were no significant differences in carbohydrate, protein and fat content across categories of maternal nutritional status in the respective periods. However, the fat content of human milk from 2019 was significantly higher than that of 1974 (4.7 g/dl, SD = 1.7 g/dl vs. 3.3 g/dl, SD = 1.1 g/dl; p < 0.001), while its carbohydrate content was significantly lower (6.2 g/dl, SD = 2.1 g/dl vs. 7.1 g/dl, SD = 0.2 g/dl; p < 0.001). There was no difference in the protein content between the two periods (1.4 g/dl, SD = 0.5 g/dl vs. 1.6 g/dl, SD = 0.3 g/dl; p = 0.491). The mature human milk from 2019 has a higher fat and total energy content but lower carbohydrate content than those observed 4 decades ago. The protein content remained the same.

Effect of dipotassium phosphate addition and heat on proteins and minerals in milk protein beverages

Our objective was to determine the effects of dipotassium phosphate (DKP) addition, heat treatments (no heat, high temperature, short time [HTST]: 72°C for 15 s, and direct steam injection UHT: 142°C for 2.3 s), and storage time on the soluble protein composition and mineral (P, Ca, K) concentration of the aqueous phase around casein micelles in 7.5% milk protein-based beverages made with liquid skim milk protein concentrate (MPC) and micellar casein concentrate (MCC). Milk protein concentrate was produced using a spiral wound polymeric membrane, and MCC was produced using a 0.1-µm ceramic membrane by filtration at 50°C. Two DKP concentrations were used (0% and 0.15% wt/wt) within each of the 3 heat treatments. All beverages had no other additives and ran through heat treatment without coagulation. Ultracentrifugation (2-h run at 4°C) supernatants of the beverages were collected at 1, 5, 8, 12, and 15-d storage at 4°C. Phosphorus, Ca, and K concentrations in the beverages and supernatants were measured using inductively coupled plasma spectrometry. Protein composition of supernatants was measured using Kjeldahl and sodium dodecyl sulfate-PAGE. Micellar casein concentrate and MPC beverages with 0.15% DKP had higher concentrations of supernatant protein, Ca, and P than beverages without DKP. Protein, Ca, and P concentrations were higher in MCC supernatant than in MPC supernatant when DKP was added, and these concentrations increased over storage time, especially when lower heat treatments (HTST or no heat treatment) had been applied. Dipotassium phosphate addition caused the dissociation of αS-, β-, and κ-casein, and casein proteolysis products out of the casein micelles, and DKP addition explained over 70% of the increase in supernatant protein, P, and Ca concentrations. Dipotassium phosphate could be removed from 7.5% of protein beverages made with fresh liquid MCC and MPC (containing a residual lactose concentration of 0.6% to 0.7% and the proportional amount of soluble milk minerals), as these beverages maintain heat-processing stability without DKP addition.

Effect of a blend of cinnamaldehyde, eugenol, and Capsicum oleoresin on methane emission and lactation performance of Holstein-Friesian dairy cows

This study aimed to investigate the effect of administering a standardized blend of cinnamaldehyde, eugenol, and Capsicum oleoresin (CEC) to lactating dairy cattle for 84 d (i.e., 12 wk) on enteric CH4 emission, feed intake, milk yield and composition, and body weight. The experiment involved 56 Holstein-Friesian dairy cows (145 ± 31.1 d in milk at the start of the trial; mean ± standard deviation) in a randomized complete block design. Cows were blocked in pairs according to parity, lactation stage, and current milk yield, and randomly allocated to 1 of the 2 dietary treatments: a diet including 54.5 mg of CEC/kg of DM or a control diet without CEC. Diets were provided as partial mixed rations in feed bins, which automatically recorded individual feed intake. Additional concentrate was fed in the GreenFeed system that was used to measure emissions of CO2, CH4, and H2. Feeding CEC decreased CH4 yield (g/kg DMI) by on average 3.4% over the complete 12-wk period and by on average 3.9% from 6 wk after the start of supplementation onward. Feeding CEC simultaneously increased feed intake and body weight, and tended to increase milk protein content, whereas no negative responses were observed. These results must be further investigated and confirmed in longer-term in vivo experiments.

Functional proteins in breast milk and their correlation with the development of the infant gut microbiota: a study of mother-infant pairs.

Proteins in breast milk play an important role in the growth and development of infants. This study aims to explore the correlation between functional proteins in breast milk and the infant gut microbiota. Twenty-three mothers and their infants were enrolled and breast milk samples and infant fecal samples were collected. Breast milk protein content was determined by UPLC-MS/MS, and 16S rRNA sequencing was employed to analyze the gut microbiota of infant. The results indicated that the secretory immunoglobulin A (sIgA) content in breast milk was positively correlated with the abundance of Veillonella parvula. The κ-casein content was positively correlated with the abundance of Clostridium butyricum. The osteopontin (OPN) and lactalbumin contents were positively correlated with the abundance of Parabacteroides distasonis at 42 days. Functional pathway analysis showed that the OPN and κ-casein contents in breast milk were significantly correlated with amino acid, pyruvate, propionic acid, linoleic acid, and alpha-linolenic acid metabolic pathways in early life. The results of this study suggest that specific proteins in breast milk can influence the abundance of certain gut microbes in infants, playing an important role in early immune and metabolic development.

The Need for Culturally Appropriate Food Allergy Management Strategies: The Indian Milk Ladder.

Cow's milk allergy (CMA) is one of the most common and complex food allergies affecting children worldwide and, with a few exceptions, presents in the first few months of life. Baked-milk-containing diets are well tolerated in the majority of milk-allergic children and allow dietary restrictions to be relaxed. In addition, the early introduction of tolerated forms of allergenic foods to an infant's diet in small amounts may enhance the outgrowth of their milk allergy through oral tolerance induction. The methods of milk introduction vary widely across the globe. We convened an expert group to develop a comprehensive milk ladder based on the calculated milk protein content of Indian foods. To validate the milk ladder, the foods chosen for the ladder were analyzed and the ladder was re-evaluated based on the cooked milk protein content. Combining expert consensus and validation of milk protein content, we created the world's first milk ladder containing Indian foods. This is the first ladder that provides information on the timing and temperature of cooking, with validated milk protein content. This is the first milk ladder based on the unique features of Indian food habits built by the consensus of Indian experts along with international collaboration with laboratory quantification of milk protein in each step. We believe the "The Indian Milk Ladder" will be a very helpful tool for pediatricians helping manage CMA in children as well as their parents and caregivers, not only in India, but in countries world-wide where these foods are commonly consumed.

Comparison of milk protein concentrate, micellar casein, and whey protein isolate in loading astaxanthin after the treatment of ultrasound-assisted pH shifting

Milk proteins can be used as encapsulation walls to increase the bioavailability of active compounds because they can bind hydrophobic, hydrophilic, and charged compounds. The objective of this study was to investigate the effects of astaxanthin (ASTA) encapsulation and the functional properties of milk protein and ASTA nanocomposites by an ultrasound-assisted pH-shifting treatment of different milk proteins, including milk protein concentrate (MPC), micellar casein (MCC), and whey protein isolate (WPI). The ultrasound-assisted pH-shifting treatment of milk protein helped to improve the encapsulation rate of ASTA. Therein, MCC showed great improvement of encapsulating ASTA after co-treatment with the raised encapsulated rate of 5.11%, followed by WPI and MPC. Furthermore, the nanocomposites of ASTA with milk protein exhibit improved bioavailability, antioxidant capacity, and storage stability. By comparison, MCC-encapsulated ASTA has the best storage stability, followed by MPC, and WPI-encapsulated ASTA has the least stability over a 28-d storage period. The results of intrinsic fluorescence and surface hydrophobicity showed that milk protein underwent fluorescence quenching after binding to ASTA, which was due to the hydrophobic sites of the protein being occupied by ASTA. In general, the nanocomposites of milk protein and ASTA fabricated by using an ultrasound-assisted pH-shifting treatment have the potential to be better nano-delivery systems for ASTA in functional foods, especially MCC, which showed excellent performance in encapsulation after treatment technique.

Energy and nitrogen utilization of lactating dairy cattle fed increasing inclusion of a high-protein processed corn coproduct*

Advancing technologies of the corn dry-milling ethanol production process includes the mechanical separation of fiber-containing particles from a portion of plant- and yeast-based nitrogenous particles. The resulting high-protein processed corn coproduct (HPCoP) contains approximately 52% crude protein (CP), 36% neutral detergent fiber (NDF), 6.4% total fatty acids (TFA). The objective of this experiment was to examine the effects of replacing nonenzymatically browned soybean meal with the HPCoP on dry matter intake (DMI), energy and N utilization, and milk production of lactating Jersey cows. Twelve multiparous Jersey cows were used in a triplicated 4 × 4 Latin square design consisting of four 28-d periods. Cows were blocked by milk yield and assigned randomly to 1 of 4 treatment diets that contained HPCoP (dry matter [DM] basis) at (1) 0%; (2) 2.6%; (3) 5.4%; and (4) 8.0%. Diets were formulated to be isonitrogenous and thus replace nonenzymatically browned soybean meal with HPCoP in the concentrate mix, while forage inclusion remained the same across diets. Increasing the concentration of HPCoP had no effect on DMI (mean ± SE; 19.9 ± 0.62 kg/d), but tended to linearly increase milk yield (27.8, 28.5, 29.8, and 29.0 ± 1.00 kg/d). Although no difference was observed in the concentration of milk protein with increasing inclusion of HPCoP (3.40% ± 0.057%), the concentration of fat linearly increased with the inclusion of HPCoP (5.05%, 5.19%, 5.15%, 5.47% ± 0.18%). No differences were observed in the digestibility of DM, NDF, CP, TFA, and gross energy averaging 66.6% ± 0.68%, 49.0% ± 1.03%, 66.1% ± 0.82%, 73.6% ± 1.73%, 66.3% ± 0.72%, respectively, with increasing HPCoP inclusion. The concentration of dietary gross energy linearly increased with increasing concentrations of HPCoP (4.25, 4.26, 4.28, and 4.31 ± 0.01 Mcal/kg), but no difference was observed in digestible energy and metabolizable energy (ME) across treatments averaging 2.83 ± 0.033 and 2.53 ± 0.043 Mcal/kg, respectively. Concentration of dietary net energy for lactation (NEL) tended to increase with increasing HPCoP (1.61, 1.72, 1.74, 1.72 ± 0.054 Mcal/kg) with the ratio of NEL:ME increasing linearly with increasing HPCoP inclusion (0.648, 0.676, 0.687, 0.677 ± 0.0124). Results of this study suggest that inclusion of the HPCoP can replace nonenzymatically browned soybean meal and support normal milk production.

Dynamic lactation responses to dietary crude protein oscillation in diets adequate and deficient in metabolizable protein in Holstein cows

Limited research has examined the interaction between dietary crude protein (CP) level and CP feeding pattern. We tested CP level (low protein [LP], 13.8%; high protein [HP], 15.5% CP, dry matter [DM] basis) and CP feeding pattern (OF = oscillating, SF = static) using a 2 × 2 factorial in 16 mid- to late-lactation Holsteins (initially 128 ± 12 d in milk; mean ± SD). Cows ate total mixed rations formulated by exchanging soy hulls and ground corn with solvent soybean meal to keep constant ratios of neutral detergent fiber to starch (1.18:1), rumen-degradable protein to CP (0.61:1), and forage-to-concentrate (1.5:1) in DM. The OF treatments alternated diets every 48 h to vary CP above and below the mean CP level (OF-LP = 13.8% ± 1.8%; OF-HP = 15.5% ± 1.8% CP [DM basis]) whereas diets were constant in SF (SF-LP = 13.8%; SF-HP = 15.5% CP [DM basis]). In four 28-d periods, 8 rumen-cannulated and 8 noncannulated cows formed 2 Latin rectangles. On d 25 to 28 of each period, each cow's feed intake and milk production were recorded, and samples were taken of orts (1×/d) and milk (2×/d). We fit linear mixed models with fixed CP level, CP feeding pattern, and period effects, and a random intercept for cow, computing least squares means and standard errors. Neither CP level, CP feeding pattern, nor the interaction affected DM intake, feed efficiency, or production of milk, fat- and protein-corrected milk (FPCM), fat, true protein, or lactose. Milk urea-N (MUN) yield was lesser for LP. The LP and OF conditions decreased MUN concentration. The CP level tended to interact with CP feeding pattern so that milk protein concentration was greatest for OF-HP. The OF and LP conditions increased the ratio of true protein to MUN yield. Within OF, cosinor mixed models of selected variables showed that cows maintained production of FPCM across dietary changes, but MUN followed a wave-pattern at a 2-d delay relative to dietary changes. A tendency for lesser MUN with OF contradicted prior research and suggested potential differences in urea-N metabolism between OF and SF. Results showed that cows maintained production of economically-relevant components regardless of CP feeding pattern and CP level. Contrary to our hypothesis, the effects of 48-h oscillating CP were mostly consistent across CP levels, suggesting that productivity is resilient to patterned variation in dietary CP over time even when average CP supply is low (13.8% of DM) and despite 48 h restrictions at 12.2% CP.