Milk Solids Research Articles

Life Cycle Assessment of Dairy Products: A Case Study of a Dairy Factory in Brazil

The production of dairy products generates several environmental impacts, and life cycle assessment (LCA) is a useful methodology to quantify and understand those impacts. In Brazil, some traditional dairy products have not yet been evaluated using the LCA methodology. Based on this gap, we conducted a cradle-to-gate LCA of six dairy products from a plant in Minas Gerais, Brazil. We also performed two sensitivity analyses. The first analysis was on how the environmental profiles of the products changed depending on how the multifunctional processes were allocated. The second analysis evaluated how these changes in environmental profiles occurred depending on the way that the impacts were allocated to products and by-products (whey and buttermilk) produced within the dairy factory. Among the dairy products studied, the impacts of mozzarella cheese and butter substantially surpassed those of other products; cheese spread and dulce de leche had a similar impact; and yoghurt and milk had the lowest values for the impact categories that were assessed. The inclusion of by-products in the analysis proved to be an effective way to reduce the environmental impacts attributed to the dairy products, especially for cheese and cheese spread, the impact values of which decreased by 56% and 46%, respectively. Additionally, the use of different strategies to deal with the multifunctional processes significantly affected the impact results of the dairy products. The subdivision of processes combined with causal allocation was the best alternative as opposed to the allocation by milk solids. These results could offer a better understanding of the environmental profiles of dairy products from Brazil, especially the traditional products, such as dulce de leche and cheese spread. Other contributions of this study include the proposal of alternatives that could improve the environmental profiles of products (such as the processing of by-products and the questioning of the use of allocation according to milk solids, which have been commonly used in other life cycle assessment studies) and the proposal of a better method for assessing the environmental impacts of dairy products.

Characterization and mitigation option of greenhouse gas emissions from lactating Holstein dairy cows in East China

BackgroundThis study investigated greenhouse gas (GHG) emission characteristics of lactating Holstein dairy cows in East China and provided a basis for formulating GHG emission reduction measures. GreenFeed system was used to measure the amount of methane (CH4) and carbon dioxide (CO2) emitted by the cows through respiration. Data from a commercial cow farm were used to observe the effects of parity, body weight, milk yield, and milk component yield on CH4 and CO2 emissions.ResultsMean herd responses throughout the study were as follows: 111 cows completed all experimental processes, while 42 cows were rejected because they were sick or had not visited the GreenFeed system 20 times. On average, lactating days of cows was 138 ± 19.04 d, metabolic weight was 136.5 ± 9.5 kg, parity was 2.8 ± 1.0, dry matter intake (DMI) was 23.1 ± 2.6 kg/d, and milk yield was 38.1 ± 6.9 kg/d. The GreenFeed system revealed that CH4 production (expressed in CO2 equivalent, CO2-eq) was found to be 8304 g/d, {mathrm{CH}}_{4left({mathrm{CO}}_2-mathrm{eq}right)} /DMI was 359 g/kg, {mathrm{CH}}_{4left({mathrm{CO}}_2-mathrm{eq}right)} /energy-corrected milk (ECM) was 229.5 g/kg, total CO2 production (CH4 production plus CO2 production) was 19,201 g/d, total CO2/DMI was 831 g/kg, and total CO2/ECM was 531 g/kg. The parity and metabolic weight of cows had no significant effect on total CO2 emissions (P > 0.05). Cows with high milk yield, milk fat yield, milk protein yield, and total milk solids yield produced more total CO2 (P < 0.05), but their total CO2 production per kg of ECM was low (P < 0.05). The total CO2/ECM of the medium and high milk yield groups was 17% and 27% lower than that of the low milk yield group, respectively.ConclusionsThe parity and body condition had no effect on total CO2 emissions, while the total CO2/ECM was negatively correlated with milk yield, milk fat yield, milk protein yield, and total milk solids yield in lactating Holstein dairy cows. Measurement of total CO2 emissions of dairy cows in the Chinese production system will help establish regional or national GHG inventories and develop mitigation approaches to dairy production regimes.

Chaya (Cnidoscolus aconitifolius, Mill. Johnston) pellet supplementation improved rumen fermentation, milk yield and milk composition of lactating dairy cows

• Chaya ( Cnidoscolus aconitifolius ) leaf pellet (CHYP) contains high level of crude protein and minerals. • CHYP supplementation enhanced nutrient digestibility, propionic acid (C 3 ) and balanced rumen pH and reduced calculated methane emission. • CHYP can improve milk yield and milk composition. Chaya ( Cnidoscolus aconitifolius , Mill. Johnston) is a fodder shrub that contains flavonoid compounds and uses as feeds, medicine and food, respectively. This study examined the effects of Chaya leaf pellet (CHYP) supplementation on nutrient digestibilities, feed intake, rumen fermentation, milk yield and milk compositions. Four lactating crossbred (75% Holstein-Friesian × 25% Thai native cows) dairy cows with average body weight (440 ± 10), milk production (12 ± 2 kg/h/d) and days- in- milk (126 ± 20) were randomly assigned to a 2 × 2 factorial arrangement in a 4 × 4 Latin square design. Two ratio of concentrate to milk yield, (1:1; CM1 and 1:2; CM2) and two CHYP levels at 0 and 6% of total dry matter intake (TDMI) were imposed. The results revealed that concentrate to milk yield ratio and CHYP supplementation had interactive effect ( P < 0.05) on nutrient intake except ADF, fat -corrected milk and total solids. Rumen pH was decreased ( P < 0.05) in cows receiving high concentrate, while the pH was in normal range for animals fed with CHYP. Ruminal NH 3 -N concentration was increased ( P < 0.05) by the 6% CHYP supplementation. The level of blood urea nitrogen (BUN) ( P < 0.05) was increased with the increase of ruminal NH 3 -N ( P < 0.01), and bacterial population, while the, protozoal counts were slightly reduced by the supplementation of CHYP. The CHYP supplementation significantly increased total VFA and propionate concentration, while decreased acetate to propionate ratio and estimated methane emission. In conclusion, concentrate to milk yield at 1:1 ratio and CHYP supplementation at 6% significantly modulated rumen fermentation end-products and milk composition in lactating dairy cows.

Feeding native rumen microbial supplements increases energy-corrected milk production and feed efficiency by Holstein cows

The objective of this study was to investigate the effects of 2 novel native microbial feed supplements (MFS) on milk yield, milk composition, dry matter intake (DMI), body weight (BW), body condition score (BCS), and efficiency. A total of 73 lactating Holstein cows were enrolled over 4 mo. During a 2-wk covariate period, baseline data were collected. Using a randomized complete block design, cows were blocked in groups of 3 by days in milk (DIM), production, and parity. Within blocks cows were randomly assigned to a basal diet with a 150 g/d ground corn topdress and no MFS (control), the basal diet supplemented with a 5 g/d dose of Clostridium beijerinckii ASCUSDY20 and Pichia kudriavzevii ASCUSDY21 in a carrier mixed with a 150 g/d ground corn topdress (MFS1), or the basal diet with a 5 g/d dose of Ruminococcus bovis ASCUSDY10, Butyrivibrio fibrisolvens ASCUSDY19, Clostridium beijerinckii ASCUSDY20, and Pichia kudriavzevii ASCUSDY21 in a carrier mixed in a 150 g/d ground corn topdress (MFS2) for 140 d. Cows were fed the diets as a total mixed ration (TMR) for ad libitum DMI once daily. Analysis showed numerical increases in performance variables such as milk yield and fat and protein contents in both MFS1 and MFS2, although the differences were not significant over time. For energy-corrected milk (ECM), other solids percentage, and BW there were significant treatment by time interactions. Cows fed MFS1 and MFS2 produced 1.4 kg/d and 1.6 kg/d more ECM than control cows, respectively (time-dependent treatment significance). Up to wk 13 of treatment, both MFS groups had higher ECM production than the control group but after this point MFS1 rapidly decreased to the same level as control. All cows displayed a gradual decrease in ECM after wk 13 but the MFS2 group remained greater than both control and MFS1. A similar trend in the content of other milk solids was observed. Cow BW was affected over time; both control and MFS2 cows gained weight at a similar rate throughout the study, whereas the weight gain of MFS1 cows decreased briefly from wk 13 to 17 before increasing again. Feed efficiency tended to be improved by MFS, with greater improvement by MFS2 than by MFS1. The DIM when the supplementation began had a significant impact on MFS2 efficacy, where the supplementation of native rumen microbes at an earlier DIM resulted in a greater gain in ECM over the 140-d trial. A similar trend was observed for MFS1, although the effect was not significant. Our results suggest that dairy cow lactation stage and energy requirements also play an important role in product efficacy.

Comparative Analysis of Protein in Selected Infant Formula Using Dye-Binding and Formol Methods

Aim: The protein content of some infant milk formula was determined using Dye-binding and Formol methods in comparison to the manufacturer’s values as reference.&#x0D; Study Design: The study was an experimental design.&#x0D; Place and Duration of Study: This study was carried out at the laboratory of Chemistry department, Federal University of Agriculture, Makurdi, Nigeria between June, 2021 and December, 2021.&#x0D; Methodology: Dye-binding Method was done by weighing about 5 g of the baby milk samples into beakers and 100 mL distilled water was added and mixed thoroughly. 20 mL of diluted 80% orange G dye solution was added to 2 mL of the milk solution and shaked vigorously. The sample was centrifuged at 820 rpm for 5 minutes and a clear filtrate obtained whose absorbance was then analyzed using spectrophotometer. For Formol Method I g of each of the milk samples was weighed into different beakers then 10 mL of distilled water and 0.7 mL saturated potassium oxalate was added along with 3 drops of phenolphthalein indicator into the mixture. Two drops of NaOH solution was titrated into the mixture and a pink colour appeared which diminished immediately. About 2 mL of formaldehyde was added and shaken for few seconds then titrated using sodium hydroxide (NaOH) until the mixture turned light pink.&#x0D; Results: The mean and standard deviation of protein content using Dye-binding method are; Peak baby milk 2.49 ± 0.13 g, My boy milk 2.54 ± 0.06 g. For formol methods Peak baby milk has 0.13 ± 0.01 g and My boy milk 0.1 ± 0.01 g. The result showed that both infant formula under the Dye-binding method and formol method was significantly different (p&lt;0.05) when compared to the reference value (1.7 Peak baby and 0.11 My boy). However, values obtained from Formol method for My boy milk was closest to the reference (factory value) only a slight difference of about 0.01 g.&#x0D; Conclusion: In conclusion, Formol method is more closely related to the reference values (manufacturer’s values). Thus, the Formol titration may be used with confidence as a quick test for approximating the protein content of skim milk solids which is typical of baby milks.

Predictive formulas for different measures of cheese yield using milk composition from individual goat samples

The objective of this study was to develop formulas based on milk composition of individual goat samples for predicting cheese yield (%CY) traits (fresh curd, milk solids, and water retained in the curd). The specific aims were to assess and quantify (1) the contribution of major milk components (fat, protein, and casein) and udder health indicators (lactose, somatic cell count, pH, and bacterial count) on %CY traits (fresh curd, milk solids, and water retained in the curd); (2) the cheese-making method; and (3) goat breed effects on prediction accuracy of the %CY formulas. The %CY traits were analyzed in duplicate from 600 goats, using an individual laboratory cheese-making procedure (9-MilCA method; 9 mL of milk per observation) for a total of 1,200 observations. Goats were reared in 36 herds and belonged to 6 breeds (Saanen, Murciano-Granadina, Camosciata delle Alpi, Maltese, Sarda, and Sarda Primitiva). Fresh %CY (%CYCURD), total solids (%CYSOLIDS), and water retained (%CYWATER) in the curd were used as response variables. Single and multiple linear regression models were tested via different combinations of standard milk components (fat, protein, casein) and indirect udder health indicators (UHI; lactose, somatic cell count, pH, and bacterial count). The 2 %CY observations within animal were averaged, and a cross-validation (CrV) scheme was adopted, in which 80% of observations were randomly assigned to the calibration (CAL) set and 20% to the validation (VAL) set. The procedure was repeated 10 times to account for sampling variability. Further, the model presenting the best prediction accuracy in CrV (i.e., comprehensive formula) was used in a secondary analysis to assess the accuracy of the %CY predictive formulas as part of the laboratory cheese-making procedure (within-animal validation, WAV), in which the first %CY observation within animal was assigned to CAL, and the second to the VAL set. Finally, a stratified CrV (SCrV) was adopted to assess the %CY traits prediction accuracy across goat breeds, again using the best model, in which 5 breeds were included in CAL and the remaining one in the VAL set. Fitting statistics of the formulas were assessed by coefficient of determination of validation (R2VAL) and the root mean square error of validation (RMSEVAL). In CrV, the formula with the best prediction accuracy for all %CY traits included fat, casein, and UHI (R2VAL = 0.65, 0.96, and 0.23 for %CYCURD, %CYSOLIDS, and %CYWATER, respectively). The WAV procedure showed R2VAL higher than those obtained in CrV, evidencing a low effect of the 9-MilCA method and, indirectly, its high repeatability. In the SCrV, large differences for %CYCURD and %CYWATER among breeds evidenced that the breed is a fundamental factor to consider in %CY predictive formulas. These results may be useful to monitor milk composition and quantify the influence of milk traits in the composite selection indices of specific breeds, and for the direct genetic improvement of cheese production.

The relationship between dry period length and milk production of Holstein dairy cows in tropical climate: a machine learning approach.

The objective of this retrospective longitudinal study was to evaluate the relationship between dry period length and the production of milk, fat, protein, lactose and total milk solids in the subsequent lactation of Holstein dairy cows under tropical climate. After handling and cleaning of the data provided by the Holstein Cattle Breeders Association of Minas Gerais, data from 32 867 complete lactations of 19 535 Holstein animals that calved between 1993 and 2017 in 122 dairy herds located in Minas Gerais state (Brazil) were analysed. In addition to dry period length, calving age, lactation length, milking frequency, parity, calf status at birth, herd, year, and season of calving were included in the analysis as covariables to account for additional sources of variation. The machine learning algorithms gradient boosting machine, extreme gradient boosting machine, random forest and artificial neural network were used to train models using cross validation. The best model was selected based on four error metrics and used to evaluate the variable importance, the interaction strength between dry period length and the other variables, and to generate partial dependency plots. Random forest was the best model for all production outcomes evaluated. Dry period length was the third most important variable in predicting milk production and its components. No strong interactions were observed between the dry period and the other evaluated variables. The highest milk and lactose productions were observed with a 50-d long dry period, while fat, protein, and total milk solids were the highest with dry period lengths of 38, 38, and 44 d, respectively. Overall, dry period length is associated with the production of milk and its components in the subsequent lactation of Holstein cows under tropical climatic conditions, but the optimum length depends on the production outcome.

Produksi dan Kualitas Kolostrum dan Susu Kolostrum pada Sapi Perah yang Mengkonsumsi Daun Katuk Depolarisasi

This study aims to determine the effect of additional feed with depolarizing katuk leaves on the production and quality of colostrum and colostrum milk in Friesian Holstein dairy cows. There were 21 dairy cows that had just giving birth, divided into 3 groups of 7 each, namely the control group (complete feed), BKD (complete feed added with Depolarizing Katuk Powder), PKD (complete feed added with Depolarizing Katuk Pellet). Depolarizing katuk feed was given 100 grams per head per day as a feed additive. Parameters observed were feed consumption, production and quality of colostrum and colostrum milk. The results showed that there was no difference in the consumption of feed supplemented with depolarizing katuk leaves, colostrum production, milk density, total solid colostrum, Solid non-fat, lactose contents, and protein contents of colostrum and colostrum milk compared to the control group. Significant differences occurred in colostrum milk production, total solid colostrum milk, and fat content of colostrum and colostrum milk. It was concluded that depolarizing katuk leaves could be used as additional feed to increase the production and total solids of colostrum milk, and increase the fat content of colostrum and colostrum milk.&#x0D; &#x0D; Keywords: colostrum, colostrum milk, depolarizing katuk leaf, Friesian Holstein

Yield and quality of cheese from milk of cows of different genotypes by halloumi technology

The purpose of the research was to carry out a comparative assessment of the quality of grilled cheese (halloumi) obtained from the milk of cows of three genotypes. The cheese was prepared according to the Cypriot halloumi technology, but instead of sheep or goat milk, they used cattle milk. The milk of red-mottled cows differed from the milk of other breeds with a higher content of skimmed milk solids, protein and fat. Grilled cheese made from milk of cows of all genotypes, manufactured using hallumi technology, meets the requirements of GOST R 52686-2006 and is bold (Simmental cows) or fat (black-mottled and red-mottled breeds). Grilled cheese made using hallumi technology from the milk of red-mottled cows has an average moisture content, an average density, a higher yield and is more saturated with lactic acid than cheese from the milk of Simmental and black-mottled breeds. Halloumi grilled cheese made from milk of cows of all three genotypes is suitable for roasting within 6 days from the date of production.

Zeboid cow milk: physicochemical quality indicator

Introduction. A herd of zeboid cattle was created by the Snegiri Scientific and Experimental Farm (Moscow region, Russia) as a result of long-term selection and crossbreeding zebu (Bos indicus L.) with cattle (Bos taurus L.). These hybrid cows have good physiological parameters, high resistance to diseases, and a significant adaptive potential. The quality of milk produced by zebu cows at different lactation and milking times has not been studied as well as their milking capacity. Therefore, we aimed to assess the variability of specific physicochemical indicators of milk produced by Snegiri’s zeboid dairy herd.&#x0D; Study objects and methods. The milk of 193 zeboid cows (6–12% of zebu blood) from the Snegiri Farm was analyzed by standard methods for quality indicators such as fat, nonfat milk solids, density, bound water, freezing point, protein, and lactose. Then, we determined how these indicators changed depending on the lactation number and the time of milking (morning/evening). Statistical analysis was applied to process the data.&#x0D; Results and discussion. Such indicators as nonfat milk solids, density, bound water, freezing point, protein, and lactose of zeboid cow milk were consistent with the normal indicators for raw cow’s milk. Only its fat content (4.39%) exceeded the norm. We found no correlation between the quality of milk and the number of lactations. However, the evening milk was more concentrated, with a significant increase in nonfat milk solids and density, as well as with a lower freezing point.&#x0D; Conclusion. Zeboid cows, which can be bred in suboptimal conditions, produce milk suitable for dairy products since it has a high fat content regardless of lactation and milking time.

Comparison of Ethanol Stability and Chemical Composition of Camel Milk from Five Samples.

Simple SummaryCamel milk has recently gained the interest of consumers and the dairy industry, as it is widely suggested as an ideal substitute for cow milk. The nutritional value and the bioactivity of camel milk proteins have received particular attention from research groups and industrial companies around the world. Camel milk proteins can be used as ingredients in the manufacturing and stabilization of foods and beverages; however, in these applications, the controlled aggregation of milk proteins and stability at high temperatures and in alcohol are desirable. The ethanol stability of milk could be used as an indicator of its freshness and provide information on the stability of raw milk ultra-high temperatures and powder processing.This research was carried out to study the variation in ethanol stability and chemical composition of five camel milk samples, including two pasteurized samples (Alwatania and Darir alabaker) and three raw samples (Majaheim, Wadah, and Hamra). Ethanol stability was analyzed by dispersing camel milk samples with 0 to 100% ethanol (v/v). The findings indicate that camel milk samples precipitated after adding an equal volume of ethanol at concentrations between 50% and 64% ethanol, depending on the milk sample. The addition of sodium chloride at different concentrations (1–10%) to camel milk resulted in a significant increase in ethanol stability, and samples from Majaheim and Alwatania exhibited the highest ethanol stability values (88%). In contrast, the addition of EDTA to camel milk for pH ranging between 5.9 and 7.1 has increased ethanol stability with a sigmoidal shape in camel milk. The largest ethanol stability differences were observed in a camel milk sample from Alwatania. Thus, the level of Ca2+ in camel milk may contribute to ethanol stability by shifting the entire profile to higher ethanol stability values. The chemical composition of different camel samples was also determined. The lactose content of camel milk varied significantly (p < 0.05) across samples, ranging from 4.37% in Majaheim camel milk to 4.87% in Alwatania camel milk. The total solids of camel milk varied significantly between raw and pasteurized samples, ranging between 10.17% and 12.10%. Furthermore, protein concentration in camel milk obtained from different camel samples varied, from 2.43% to 3.23% for Hamra and Alwatania, respectively. In conclusion, ethanol stability in camel milk was dependent on the camel breed, pH level, ionic strength, and EDTA addition.

Access time to pasture under wet soil conditions: Effects on productivity and profitability of pasture-based dairying

A long grazing season improves the profitability of pasture-based dairy production. It can entail grazing under wet soil conditions and the risk of damaging swards. Housing cows either temporarily or completely while soil moisture is high can avoid damaging swards. An experiment with 4 grazing systems was conducted over 3 yr (Sep. 1, 2013, to Aug. 31, 2016). The purpose was to evaluate whether soil moisture measurements are an effective decision support to assess the risk of treading damage and effects on pasture productivity and dairy cow performance during wet soil conditions. Access time to pasture between February and December of each grazing season was dependent on volumetric soil moisture content (VSMC, m3/m3) measured each morning: Control = cows were housed at VSMC >0.5 and otherwise allowed 22 h/d access to pasture; S<7 = cows were housed on days with VSMC >0.7 and otherwise allowed 22 h/d access to pasture; S7-6 = cows were housed at VSMC >0.7 and allowed 8 h/d access to pasture at VSMC between 0.7 and 0.6 and 22 h/d access at VSMC ≤0.6; S7-5 = cows were housed at VSMC >0.7 and allowed 8 h/d access to pasture at VSMC between 0.7 and 0.5 and 22 h/d access at VSMC ≤0.5. Cows with 8-h access per day received no other feeding when housed. All herds were compact spring-calving, with a mean calving date of Feb. 19. Mean stocking rate was 2.57 cows/ha. Measurements of VSMC provided an objective indicator for the risk of treading damage. Less time spent at pasture under wet soil conditions lowered treading damage but had no effect on annual pasture production (mean 14.8 t of organic matter/ha). Annual milk solids production per cow was lowest for the control herd (485 kg) and not different between the other systems (503 kg). Reducing treading damage to swards did not improve productivity or profitability of the grazing systems. Nevertheless, measuring soil moisture was a useful decision support for assessing the risk of treading damage when turning cows out to pasture.

Quinoa flour as a skim milk powder replacer in concentrated yogurts: Effect on their physicochemical, technological, and sensory properties.

Milk standardization with solids (i.e., nonfat milk solids, MSNF) for yogurt manufacture is traditionally achieved by the addition of skim milk powder (SMP). However, the addition of SMP to milk‐based yogurt increases lactose content and decreases both protein content and gel firmness. Thus, in this work, quinoa flour (QF; 0%, 25%, 50%, 75%, and 100% w/w) was used to replace SMP in concentrated yogurt. The physicochemical, textural, and sensory properties and microstructure of the yogurt were evaluated during cold storage. Generally, protein content, water‐holding capacity, and L* value decreased, while syneresis, textural attributes, and viscosity increased with increasing QF content. The substitution of high levels of QF (>25%, w/w) for SMP led to significantly shorter fermentation times, as compared to the control sample. The scanning electron microscopy observations showed significant changes in the yogurt microstructure as a consequence of QF replacement. Samples with 25% (w/w) substitution of QF and control had the highest scores in overall acceptance. According to the results, QF could be applied as an interesting raw material for concentrating the milk‐based yogurt at substitution level of 25% (w/w).

Feeding System Effects on Dairy Cow Rumen Function and Milk Production.

Simple SummaryIn ruminants, diet has a significant effect on rumen function. Hence, this study was conducted to see if changing the normal grass-based diet of cows could change rumen function and milk production. Therefore, we compared three diets: Grass (cows grazing grass-only), Grass-Clover (cows grazing grass-white clover only) and cows fed a total mixed ration (TMR) diet indoors. We monitored the cows over the course of a full lactation cycle in a spring-calving system. In order to examine rumen function, some of the cows had a cannula placed in their rumen so that we could collect rumen contents samples. After we collected the samples and analysed the data we found that the type of diet the cows were offered did significantly affect milk production; milk yield and milk solids yield were generally highest on the TMR diet. When we looked at the rumen sample data we found that diet also affected rumen function; it altered the rumen volatile fatty acid (VFA), and ammonia and lactic acid profiles significantly but did not effect on rumen pH. Clover inclusion in the diet led to higher total rumen VFA and ammonia concentrations and higher milk urea nitrogen compared to the grass and TMR diets. We suggest this indicates a higher protein intake on that diet. Given these findings, we concluded that a clover-based diet could significantly alter rumen function, milk composition and milk yield in dairy cows.Good rumen function, which is largely influenced by the diet of the cow, is essential to optimise animal performance. This study, conducted over the course of a full lactation in a spring-calving milk production system, compared the rumen function and milk production of cows offered one of three dietary treatments: (1) Cows grazing grass-only swards receiving 250 kg nitrogen (N)/ha/year (Grass), (2) Cows grazing grass-white clover swards receiving 250 kg N/ha/year (Grass-Clover), and (3) Cows offered a total mixed ration diet and housed indoors (TMR). Treatment significantly affected milk production; milk yield and milk solids yield were generally highest on the TMR treatment. There was no effect of treatment on rumen pH. However, treatment significantly altered the rumen volatile fatty acid (VFA), and ammonia and lactic acid profiles. Clover inclusion in the sward led to higher (p < 0.05) total VFA and ammonia concentrations compared to the Grass and TMR treatments. The increased rumen ammonia concentration was associated with a significantly greater milk urea nitrogen (MUN) content in the milk from cows fed on Grass-Clover, indicating a greater excess of dietary protein in that treatment. It was concluded that a clover-based dairy cow feeding system could significantly alter rumen function, milk composition and milk yield.

Nitrogen Excretion by Dairy Cows Grazing Plantain (Plantago lanceolata) Based Pastures during the Lactating Season.

Simple SummaryPlantain (Plantago lanceolata) has emerged as a forage with the ability to reduce nitrogen (N) losses, in particular N leaching, from grazing dairy systems. For farmers to confidently incorporate plantain into their farms, research needs to demonstrate that these environmental benefits sustain similar production and farm profit than traditional ryegrass (Lolium perenne)–white clover (Trifolium repens, wc)-based pasture. The effect of changing the cows’ diet to plantain-based pastures was evaluated over two lactation seasons in comparison to ryegrass–wc pastures. Cows grazing plantain-based pastures produced the same milk solids production, but a urine with a lower N concentration when compared to ryegrass–wc pastures. Plantain reduced the urinary N loads from individual urine patches via higher urine volume and reduced the total N loading onto pastures via a lower urinary N excretion to mitigate the N leaching losses from grazed pastures. Plantain pastures could be employed by farmers to reduce the nitrate leaching from dairy farms.The use of plantain pasture in dairy systems can potentially reduce nitrogen (N) leaching losses via the lower N concentration in the urine (UNc) of cows. Reducing the urinary N load while cows graze pastures can reduce the risk of N leaching losses from urine patches. Research needs to demonstrate that these environmental benefits are not at the expense of milk production and farm profit. Three groups of 20 cows grazed in the following three pasture treatments: (i) plantain, (ii) plantain–clover mix (plantain, red [Trifolium pratense] and white clover), or (iii) ryegrass-white clover (wc) pastures, from spring to autumn for two years. Each year, pasture intake, diet quality, milk production and animal N (milk and urine) excretion were evaluated in spring, summer, and autumn. The cows grazing the plantain and plantain–clover mix pastures produced similar milk solids as cows grazing ryegrass–wc pasture but reduced their UNc during summer and autumn, when compared to those grazing the plantain–clover mix and ryegrass–wc pastures. Plantain reduced urinary N loads onto pastures by a greater number of urine patches with lower urinary N loading rates. The results demonstrate that plantain pastures do not diminish milk solids production from cows, and the lower UNc from summer to autumn could reduce N being lost to the environment.

Physical and economic performance of dairy cows managed within contrasting grassland-based milk production systems over 3 successive lactations

A diverse range of grassland-based milk production systems are practiced on dairy farms in temperate regions, with systems differing in relation to the proportion of grazed grass, conserved forages and concentrates in diet, calving season, duration of housing, cow genotype, and performance levels. The current study was conducted to examine performance within diverse grassland-based systems of milk production under experimental conditions. This study examined 4 milk production systems over 3 successive lactations (20 cows per system during each lactation). With winter calving-fully housed (WC-FH), Holstein cows were housed for the entire lactation and offered a complete diet consisting of grass silage, maize silage, and concentrates [approximately 50% forage on a dry matter (DM) basis]. With winter calving-conventional (WC-Con), Holstein cows were housed and offered the same diet from calving until turnout (late March) as offered with WC-FH, and thereafter cows were given access to grazing and supplemented with 5.0 kg of concentrate/cow daily. Two spring-calving systems were examined, the former involving Holstein cows (SC-H) and the latter Jersey × Holstein crossbred cows (SC-J×H). Cows on these systems were offered a grass silage-concentrate mix (70% forage on a DM basis) until turnout (late February), and thereafter cows were given access to grazing supplemented with 1.0 kg of concentrate/cow per day. The contributions of concentrates (3,080, 2,175, 722, and 760 kg of DM/cow per lactation), conserved forages (3,199, 1,556, 1,053, and 1,066 kg of DM/cow per lactation), and grazed grass (0, 2,041, 2,788, and 2,692 kg of DM/cow per lactation) to total DMI (6,362, 5,763, 4,563, and 4,473 kg of DM/cow per lactation) with WC-FH, WC-Con, SC-H, and SC-J×H, respectively, varied considerably. Similarly, milk yield (9,333, 8,443, 6,464, and 6,049 kg/cow per lactation), milk fat content (44.9, 43.3, 42.8, and 49.0 g/kg), and milk protein content (34.6, 34.9, 33.6, and 36.3 g/kg) differed between systems (WC-FH, WC-Con, SC-H, and SC-J×H, respectively). The higher milk yields with the WC systems reflect the greater concentrate inputs with these systems, whereas the greater milk fat and protein content with SC-J×H reflect the use of Jersey crossbred cows. Crossbred cows on SC-J×H produced a similar yield of milk solids as Holstein cows on SC-H. Cows on WC-FH ended the lactation with a greater body weight (BW) and body condition score than cows on any other treatment. While Jersey crossbred cows on SC-J×H had a lower BW than Holstein cows on SC-H, cows on these 2 systems were not different for any of the other BW, body condition score, or blood metabolite parameters examined. Cows on WC-FH had a greater interval from calving to conception, a greater mastitis incidence, and a greater locomotion score than cows on the spring calving systems. Whole-system stocking rates and annual milk outputs were calculated as 2.99, 2.62, 2.48, and 2.50 cows/ha, and 25,706, 20,822, 15,289, and 14,564 kg of milk/ha, with each of WC-FH, WC-Con, SC-H, and SC-J×H, respectively. Gross margin per cow was highest with WC-Con, gross margin per hectare was highest with WC-FH, and gross margin per kilogram of milk was highest with SC-J×H. This study demonstrated that diverse grassland-based milk production systems are associated with very different levels of performance when examined per cow and per hectare.

Recent developments in dairy kefir-derived lactic acid bacteria and their health benefits

Kefir is one of the most consumed traditional fermented dairy products and it has a complex probiotic and nutritional composition. Kefir grain contains casein and other milk solids together with the yeasts and lactobacilli that cause the characteristic kefir fermentation and serve as a starter to induce this fermentation when introduced into fresh milk. Both kefir and kefir grains have a rich microbiota and their composition is affected by many parameters like kefir origin, production method (artisanal or industrial), kefir grain: milk ratio, type of milk, fermentation conditions, inoculum source, equipment used in production and storage conditions. Lactic acid bacteria (LAB) are a significant part of the kefir's microbial composition and the health-promoting effects. Kefir-derived LAB have beneficial effects on colorectal cancer, cardiovascular diseases, type 2 diabetes mellitus, obesity, kidney diseases, modulation of the immune system as well as intestinal microbiota through different biological mechanisms. In addition, bioactive peptides and metabolic products of kefir have shown promising results as health beneficial components along with certain antiviral effects including COVID-19. Therefore, this article is up-to-date information about the production, processing as well as health benefits of dairy kefir-derived LAB with future prospect of work.

Size of the prize: the value of closing pasture yield gaps on heterogeneous soil types in a dairy farm in Canterbury, New Zealand

Identifying opportunities to further improve pasture production on high producing, irrigated Canterbury dairy farms is complex. An innovation systems approach was used to identify the factors contributing to variation in pasture production on a case study farm such as: soil characteristics, irrigation management, and grass grub populations. This paper focuses on the value proposition of managing soil zones to optimise pasture production. Using EM38 mapping, area under a single centre pivot irrigator were characterised into soil zones of ‘low’, ‘medium’ and ‘high’. Actual measurements of irrigation application and soil characteristics were modelled in APSIM to estimate the pasture production of ‘low’ and ‘medium’ soil zones under a constant irrigation regime, giving an annual difference of 2900 kg DM/ha between the zones. In a ‘typical irrigated Canterbury System 4 dairy farm’ modelled in FARMAX, with 20% ‘low’ and 80% ‘medium’ soil zones, increasing the pasture growth in the ‘low’ zone to that of the ‘medium’ zone gave an increase of 580 kg DM/ha. This produced an increase of 51 kg/ha of milk solids and increased the stocking rate by 0.2 cow/ha, which resulted in a profit increase of $298/ha/year. The value of this on a 255 ha farm would be $75,000 per annum, while at a regional scale, increasing the productivity of the 52,900 ha of ‘low’ zone soils on irrigated dairy farms in Canterbury would add around $14 M of profit. Taking a data-driven spatial management approach to understanding the drivers of variability in pasture production has potential to identify opportunities and their potential value even in high-performing systems.

Inclusion of Barley Fodder in Alfalfa/Grass-Based Diets on Milk Production in Goats and Milking Sheep

The purpose of this study was to determine the effect of Barley Sprout Fodder (BSF) on milk production and milk composition of Saanen goats and Friesian ewes. Twenty Saanen does (1-year-old) and twenty East Friesian ewes (1 to 5 years old), were selected for this experiment, where each species was divided into four treatment groups. Goat treatments consisted of 0 (CRTL), 758 (BSF1), 1498 (BSF2) and 2270 (BSF3) g wet BSF/d added to an alfalfa/grass hay mix provided in random order. Sheep treatments were similar, but 0, 454, 908, and 1362 g wet BSF/d. The dry matter content of the fodder was 10.7%. A grain mix was fed to the goats (798 DM g/d) and sheep (400 DM g/d) during morning and evening milking. Treatment periods were fifteen days. Feed consumed was measured and milk yield and samples were collected on days 13 and 14. Milk samples were analyzed for milk fat, protein, and lactose. The cheese was made from day 14 milk and milk and cheese were analyzed for fatty acid composition. Total DM intake was between 2.7 and 2.9 kg/d for does and was different (P<0.05) between BSF treatments, 2.6 to 3.0 kg/d for ewes. Milk yield was not affected by BSF treatment. Goat milk yield averaged 2681 g/d across the treatments, while sheep was 1021 g/d. Milk fat content increased numerically from 77 to 82 g/d for goats and 50 to 58 g/d for sheep. BSF did not affect goat milk protein g/d, but sheep milk protein increased from 46 to 53 g/d. Goat milk lactose was not changed with BSF inclusion, while sheep milk lactose increased from 47 to 54 g/d. Total solids were not different from BSF in the diet for goats but was for sheep increasing from 143 to 164 g/d. There were no differences in cheese fatty acid composition for either species. The CRTL diet cost $0.82/day for goats and $0.72/d for sheep, while the high level of BSF inclusion cost $1.06/d for goats and $0.91/d for sheep. Based on the parameters of this study, the inclusion of BSF had relatively no effect on goat milk parameters but did improve milk solids in sheep milk, with no increase in milk yield.

WPŁYW POCHODZENIA OJCA NA CECHY UZYTKOWO ˙ SCI MLECZNEJ KRÓW UTRZYMYWANYCH ´ UWI ˛EZIOWO

he aim of this study, conducted under identical environmental conditions and the stanchion barn housing system, was to compare milking performance traits and somatic cell count in milk of daughters sired by Holstein-Friesian Black-and-White bulls from various origin groups. Cows were divided into three groups depending on the region of sire's origin, i.e. Polish bulls, bulls from other European countries (the Czech Republic, France and Germany) and bulls from the USA. Analyses were conducted applying the following experimental conditions: the age group of cows (primiparous vs. multiparous), stage of lactation (≤ 40 days, from 41 to 100 days, from 101 to 200 days and &gt; 200 days) and season of the year (spring, summer, autumn and winter). Results of this study indicate that at the stanchion barn housing system of dairy cows in order to increase milk yields the use of semen from bulls of imported Holstein-Friesian Black-and-White bulls seems to be beneficial. However, daughters of US bulls may be prone to elevated somatic cell counts in milk. In turn, cows sired by Polish bulls can be characterised by favourable milk solids contents.