Dairy Cow Rations Research Articles

Changes in the quality indicators of cows› milk depending on feeding the feed additive in different doses

Relevance. The quality of milk depends on the season, the breed of animals, the state of metabolism, the features of feeding technology and maintenance, and the feed additives fed. The doses of their feeding can affect the composition of milk. Methods. The content of mass fractions of fat, protein, lactose, its acidity, as well as the content of urea, acetone, and beta-hydroxybutyric acid in milk were determined.Results. The introduction of an experimental feed additive into the feeding rations of dairy cows had an impact on the change in the values of the indicators studied in milk. Moreover, not all the studied indicators changed under the influence of feeding this supplement. So, if we correlate the results obtained with changes in control, then, according to the authors, it is correct to talk about its significant effect on the change in the value of the mass fraction of protein in milk and the values of milk acidity: feeding in the diet of a feed additive at a dose of 1.0 kg and 1.5 kg leads to a significant increase in the mass fraction of protein in milk by 0.18% (p ˂ 0.01) and 0.15% (p ˂ 0.01), respectively, as well as a significant shift in the active acidity of milk to the alkaline side by 1.56% (p ˂ 0.001) and 0.78% (p ˂ 0.05), respectively.

Effect of Postbiotic Supplementation on Nutrient Digestibility and Milk Yield during the Transition Period in Dairy Cows.

The metabolites secreted by probiotics or released after their lysis are called postbiotics. They provide physiological benefits to the host, preventing the colonisation of pathogens by improving the intestinal environment for beneficial commensal bacteria, which reduces the incidence of digestive disorders and improves the immune system. The aim of this work was to evaluate the addition of postbiotics to dairy cow rations during the transition period on nutrient digestibility, composition, and milk yield. The effects of two postbiotics were evaluated in twelve Friesian cows from 30 days before calving to two months of lactation. The animals were randomly allocated to two treatment groups: control (CT) and supplemented with postbiotics (PC and PR). Feeding was ad libitum with 60/40 of forage/concentrate ratio on dry matter basis. Daily feed intake and milk production were recorded individually throughout the study. Two digestibility balances were performed, one before parturition and one after parturition. Colostrum was sampled at first milking and milk was sampled weekly. Data were analysed using a mixed mode in R software 4.4.1. The results suggest that postbiotic supplementation in late gestation and early lactation increase the voluntary intake of dry matter, especially in the PR treatment, with higher apparent total tract digestibility of dry matter, organic matter and neutral detergent fibre. Both treatments including postbiotics induced an increase in colostral immunoglobulin concentration. Milk production of cows receiving the PC treatment was the highest, with high fat and protein yields and a higher persistence of the production curve throughout the lactation.

Aplication of Sweet Maize Whole Plant Silage (Zea mays saccharata Sturt) and Gliricia sepium for Feed of Dairy Cattle

The low productivity of smallholder dairy cattle in Indonesia is due to limited capital and feed management. Limited land ownership, resulting in feeding from low-quality natural grasses and agricultural waste, limits milk production. Farmers rely on expensive commercial concentrate feed to improve feed quality. Efforts to improve productivity and milk quality on smallholder farms include utilizing low-cost, high-nutrient forages. Legume forages have the potential to replace commercial concentrates in dairy cow rations because they contain high crude protein (CP) and can increase livestock productivity. Using legumes as a substitute for commercial concentrates can reduce milk production costs by up to 20%. In Indonesia, the most widely cultivated legume crop is Gliricidia. Harapan Makmur Farmer Group is one of the few dairy cattle groups established in Padang City in 2011. The problem of the dairy cattle business is the high feed price, some of which comes from commercial feed. The activity method uses counseling, discussion, and the practice of making sweet corn silage mixed with Gliricidia. These activities concluded that farmers were utilizing forage from legumes to substitute commercial concentrates, and they were skilled in processing corn straw waste from sweet corn cultivation and Gliricidia into silage.

Evaluation of Partial Replacement of Barley Grain with Heated Potato Processing By-products in the Diet of Dairy Cows Using an In vitro Gas Production Technique

Background: The increasing urban population requires more dairy product (meat and milk) production; therefore, using agricultural sector by-products as animal feedstuffs has found double importance.
 Objective: The effects of replacing barley grain with heated potato slices (HPS) and French fries waste (FFW) in iso-energetic total mixed dairy cow rations on cumulative gas production and in vitro DM degradability were evaluated using in vitro techniques.
 Methods: Seven experimental dairy cow total mixed rations (TMR) were formulated based on partial replacing barley grain with HPS or FFW, including Control: a diet containing 16% (DM basis) barley grain as one of the main sources of non-forage carbohydrates; 5 HPS: a diet containing 11% barley grain and 5% HPS; 10 HPS: a diet containing 6% barley grain and 10% HPS; 15 HPS: a diet containing 1% barley grain and 15% HPS; 5 FFW: a diet containing 11% barley grain and 5% FFW; 10 FFW: a diet containing 6% barley grain and 10% FFW; 15 FFW: a diet containing 1% barley grain and 15% FFW. Two in vitro gas production approaches were conducted separately to measure the production of gas volumes and dry matter (DM) degradability at 2, 4, 6, 12, 24, 36, and 48 hours of incubation.
 Results: After 48 h of incubation, the gas production volume varied between 174 and 197 ml/g DM, with the highest value observed with control and the lowest value with FFW treatments (P < 0.05). Also, the gas production rate for the insoluble fraction varied from 0.031 to 0.054 ml/h and was higher for HPS treatments than for control and FFW treatments (P < 0.05). After 48 h of incubation, DM degradability was significantly lower for the control than other treatments. DM effective degradability, with a passage rate of 0.05 h−1, found to be higher for FFW and HPS treatments compared with the control. Moreover, the rate of the B fraction degradation was significantly lower for the control (0.14 % h−1) than for treatments.
 Conclusion: The heated potato processing by-products could be replaced with barley grain by 15% in the diet of dairy cows without having negative effects on ruminal fermentation.

The influence of sunflower oil in meals on the blood mineral profile of dairy cows

Minerals are essential substances with an important function in livestock, and their disbalance negatively affects the health and production, especially of ruminants. The addition of fat to the rations of dairy cows impacts the overall and mineral metabolism, and thus on health and production. The aim of the research was to examine the correlative relationships between balanced production meals and the mineral status of lactating cows with different ration compositions with or without the presence of vegetable oil. The research was conducted on 30 dairy cows of the Holstein breed at the Butmir farm, Sarajevo, Bosnia and Herzegovina. Three groups of 10 animals were formed based on productivity (A, 13-15 kg of milk/day, B, 19-21 kg of milk/day and C, 25-27 kg of milk/day). Samples of feed, blood plasma and milk of animals were collected on three occasions a 3-week intervals. According to the feed analysis results, the rations were standardized for each group, given for three weeks without oil,and then for three weeks with the addition of sunflower oil in the amount of 2.5% of the ration dry matter. After determining the content of basic nutrients, dry matter and ash in the rations, the concentrations of Ca, Mg, Na and K were determined by atomic absorption spectrophotometry,while the colorimetric method was used to analyse P according to Woy and Eggertz-Finkener. Analysis of blood mineral parameters was performed spectrophotometrically. The content of fat, proteins, lactose, and non-fat dry matter in milk samples was determined by infrared spectrometry using an automatic analyser. Based on the results, we observed a similarity in changes of values and the statistical significance of the differences in plasma Ca, P and Mg between the study groups and at sampling intervals. Milk production was positively correlated with the concentration of Mg and Ca with addition of the sunflower oil to the meal, while no correlation coefficient was established for P in any of the samplings. Balanced meals with and without the addition of oil did not significantly affect the content of Ca, P or Mg in the blood plasma of the tested animals, nor were significant differences found between the groups. However, by determining the correlations between milk parameters and blood biochemical parameters, a significant positive correlation was established between the amount of milk and Ca and Mg levels with a diet supplemented by oil. Given that the addition of sunflower oil in the amount of 2.5% of dry matter of the balanced rations for cows had no negative effects on the mineral profile and the parameters of the tested animals, we conclude that the introduction of this oil could be useful both from the economic point and improving nutritional composition of milk as an animal food present in the daily human diet.

Результаты применения кормовой добавки пробиотического действия для повышения продуктивности дойных коров

Abstract. The article highlights the results of scientific and economic experience on highly productive dairy cows of black-and-white breed in the second half of lactation. The purpose - evaluation of the possibility of using a new lyophilized feed additive “Bonaka-APK” in the diets of dairy cows to increase their productivity and milk quality indicators. Studied the productive effect of the feed additive “Bonaka-APK” on dairy cows. Scientific and economic experience was conducted in the farm of the OSP “Novator 1” (Gulkevichi district, Krasnodar Territory) in 2021–2022. Research objectives to study the effect of feeding the feed additive "Bonaka-APK" on milk productivity and quality indicators of cow milk. Methods. The studies were carried out on two groups of dairy cows, formed by the method of pairs of analogues. Feeding ration of dairy cows of black-and-white breed with a live weight of 550.0 ± 40.0 kg and a milk yield of 16.0 ± 3.0 kg per day contained: 170 MJ OE, 1582.0 g of digestible protein and 4100.0 g of crude fiber, including 1844.0 g of starch. The sugar-protein ratio in the diet is – 0.83. There were 93.1 g of digestible protein per 1 energy feed unit. The experimental group, in addition to the main diet as part of the compound feed, received a probiotic complex “Bonaka-APK” in the amount of 0.02 kg per 1 head, once a day before milking. Results. The use of the biotechnological complex “Bonaka-APK” as an additive to compound feed, for the accounting period, made it possible to significantly increase the milk yield of 1 cow in the experimental group by 24.6 %, and in terms of 4.0% fat content – by 26.0 % compared with control. The content of fat in the milk of the experimental groups did not differ significantly, and the content of the mass fraction of protein in the milk of the experimental group was significantly higher by 0.4% compared to the control. Scientific novelty. For the first time, a new, developed complex “Bonaka-APK” was tested on dairy cows.

Effect of a Dietary Essential Oil Blend in Dairy Cows during the Dry and Transition Period on Blood and Metabolic Parameters of Dams and Their Calves.

Cows face severe challenges of immunosuppression and negative energy balance during transition periods. The current study was designed to investigate the effects of essential oil blend supplementation in dairy cow's ration during dry periods on the health of the cow and calf. In the current study, 45 dry Holstein dairy cows were divided into three groups, each consisting of 15 animals. The control group was without any supplementation; the positive control group was only injected with 0.2 mg/kg levamisole (intramuscular) at 2 months before parturition and 1 month before parturition; and the treatment group was supplemented with 3 g/day for each cow essential oil blend mixed in total mixed ration (TMR). A mixed vaccine against E. coli, Rotavirus, and Coronavirus was administered to all cows before 42 days and after 21 days of calving. The day of the calving of the animal was accepted as day 0. Blood samples were collected from the coccygeal vein of all cows at -60, -45, -30, -15, -7, 0, 1 and 2 days, and the colostrum samples were taken on days 0, 1, and 2. Blood samples were also collected from the jugular vein (V. Jugularis) of the newborn calves on days 0, 1, and 2. The results of the hematological parameters revealed no difference in the total red blood cell count, hemoglobin amount, hematocrit, MCV, MCH, MCHC, RDW, PLT, MPV, and PCT values in both prenatal and postnatal blood of the cows (p > 0.05). In terms of immunological parameters, the total IgG level was significantly higher in the experimental group on the 7th day before birth compared to the other two groups, while the total leukocyte count, lymphocyte count, monocyte count and granulocyte counts were found to be lower after birth (p < 0005). Blood NEFA and BHBA levels were also lower in the experimental group compared to the other two groups (p < 0.005), and the blood glucose level was not different (p > 0.05). In calves, no difference was found between the groups in any of the parameters examined (p > 0.05). It is concluded that the dietary addition of an essential oil blend during the transition period enhanced the immune status and energy metabolism of cows without any effect on the health status of newborn calves.

In vitro fermentation characteristic and digestibility of dairy ration supplemented with Aspergillus oryzae inoculum

In vitro experiment has been carried out to study the effect of Aspergillus oryzae inoculum (AOI) supplementation on dairy cow rations. The observed effects include the digestibility of crude protein, NDF, dry matter and organic matter in the in vitro digestive system of the ration using rumen-buffer fluid mixture. The Experiment design using complete randomize design (CRD) consist of four treatments: Control (Commercial dairy feed), C2 (Commercial dairy feed + 2 g AOI), C4 (Commercial dairy feed + 4 g AOI) and C8 (Commercial dairy feed + 8 g AOI). The additional administration of 2, 4 and 8 grams of AOI/kg rations showed a significant difference (p<0.05) of the total volatile fatty acid content. However, the ratio of acetate/propionate (A/P) was reduced significantly. The highest increase in protein, fiber and dry matter digestibility was shown by C4 treatment (supplementation of 4 g AOI/kg ration). Based on the results of this in vitro study, the supplementation of AOI to dairy cow rations improves the digestibility of nutrients in feed.

Choice of metrics matters—Future scenarios on milk and beef production in Norway using an LCA approach

The consumption of dairy and beef products is expected to increase globally in the future, and at the same time, food must be produced in a more sustainable way, including reduced greenhouse gas (GHG) emissions, avoided feed-food competition, and reduced biodiversity loss. The purpose of the study was to a) provide an overall life cycle assessment (LCA) of these impacts for various future milk and beef production systems in Norway and b) determine how the choice of metrics for climate change affects the results. System boundaries were from cradle to farm gate and the temporal boundary was 2017 with future scenarios for 2040. The actual production and consumption in Norway in 2017 was used as a baseline (BL), and the sustainability of future Norwegian domestic production of milk and beef was assessed through three scenarios for 2040: 1) a trend yield scenario (TrendY) based on an expected increase in milk yield following the present trend, 2) a high yield scenario (HighY) with higher increase in the milk yield per cow per year than the trend, and 3) a low yield scenario (LowY) where the milk yield per cow per year was adjusted for covering the domestic demand for beef solely from dual-purpose production and no domestic specialized beef production. The beef production per dual-purpose cow was kept constant and the remaining domestic demand in scenario 1 and 2 were covered by specialized beef production. Climate change was assessed using both a GWP100 and a GWP* approach. The HighY scenario had the lowest impact on climate change using GWP100, but when taking the different behaviors of short- and long-term climate pollutants into account (GWP*), the ranking of the future scenarios changed and favored LowY. The potential biodiversity loss was lower for the LowY scenario because the proportion of concentrates in the dairy cow ration was decreased due to lower milk yield. Similarly, the feed-food competition was lower (land use ratio < 1) for the LowY. The results of our study suggest that the choice of metric for GWP and time frame highly affects the results and conclusions and strategies for climate smart and sustainable livestock production should therefore be made with caution.

The effect of teff (Eragrostis tef) hay inclusion on feed intake, digestibility, and milk production in dairy cows

Teff (Eragrostis tef) is a drought-tolerant, multi-harvest, high-quality summer forage crop. We conducted a study aiming at assessing the effect of replacing wheat hay with teff hay in diets on the feed intake, digestibility, and lactational performance of dairy cows. Thirty-four multiparous (≥3rd parity) Israeli Holstein Friesian dairy cows averaging (± SD) 182 days in milk ± 8 days in milk, 45 kg/d ± 4.8 kg/d of milk yield, and a body weight of 647.1 kg ± 51 kg at the beginning of the study were recruited to a 6-week feeding trial. Cows were randomly divided into two balanced groups based on parity, days in milk, and milk yield. Cows were subjected to two low-roughage dietary treatments (~30% roughage): a control wheat hay-based diet and a teff hay-based diet. Production performances, dry matter intake, and nutrient digestibility were measured. Milk samples were analyzed for their composition and fatty acids profile. Blood samples were used to measure metabolite concentrations. The statistical model included fixed effects of dietary treatments, time, and random effects of cows nested in treatment. Production data and feed intake were analyzed as repeated measures using a covariance structure. Dietary treatments did not affect dry matter intake (26 kg/d). However, the teff-fed cows demonstrated higher crude protein digestibility than control cows (61.9% vs. 59.2%). Dietary teff inclusion increased milk yield by 1.5 kg/d. Polyunsaturated fatty acids and omega-3 fatty acids profiles in milk were greater in the teff cows than in the control cows (4.77 g/100 g vs. 4.36 g/100 g and 3.71 g/100 g vs. 3.43 g/100 g, respectively). Non-esterified fatty acids, beta-hydroxybutyrate, and blood urea nitrogen concentrations in circulation were higher in the control group than in the teff group. The acetic-to-propionic-acid ratio in the rumen fluid was higher in control cows than in teff cows (2.90 vs. 2.43). However, the ruminal ammonia-N concentration was higher in the teff cows than in the control cows (18.5 mg/dL vs. 15.8 mg/dL). In conclusion, teff hay inclusion in the rations of high-producing dairy cows increased milk yield, which could be attributed to improved crude protein digestibility and energy partition to production.

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.

Influence of the energy and carbohydrate additive “Tanrem” on milk productivity and milk composition of cows of Holstein breed

The highest sensitivity to deficiencies in feeding is shown by highly productive cows Holstein breed that has become widespread both in Russia as a whole and in the Urals region. Against the background of many advantages of the breed, there are problems with reproduction and negative energy balance after calving. An innovative approach in feeding is the enrichment of the ration of animals with the energy and carbohydrate additive “Tanrem”, nutrients of which being natural prebiotics and energy sources, are able to activate metabolic processes. The purpose of the research was to study the effect of the energy and carbohydrate additive “Tanrem” on milk productivity and milk composition of cows of Holstein breed. Scientifi c and economic experiment was carried out in LLC “Agro-Alliance” in the Chishminsky district of the Republic of Bashkortostan. For the experiment cows of Holstein breed for the third lactation were selected in the amount of 40 animals, which were provided with the same conditions of housing. In order to select the optimal dosages of the additive the animals were divided into 4 groups. Cows of the 1st control group received the main ration adopted on the farm. Cows of the experimental groups consumed a ration enriched with the energy and carbohydrate additive “Tanrem” in a daily dose, respectively: group 2 – 250, group 3 – 500 and group 4 – 750 g/head. For 305 days of lactation the superiority of cows of the 2nd, 3rd and 4th experimental groups on the control was as follows: 198,2 kg or 2,39 % (p &lt; 0,05), 458,8 kg or 5,53 % (p &lt; 0,001) and 408,9 kg or 4,93 % (p &lt; 0,001), respectively. The data obtained indicate the expediency of enriching the ration of dairy cows with the energy and carbohydrate additive “Tanrem”. The economic analysis confirmed the established fact and indicated that the most effective rate of application of the tested additive is 500 g/head per day.

Fractionation of mixed grass and clover stands using a leaf stripper

AbstractLeys are an important part of northern European livestock production, particularly for ruminants since monogastric animals are limited in their ability to digest the fibres of the forage. Crop fractionation methods are a promising option to make forages more beneficial for monogastric animals and decrease the amount of imported protein feed. A leaf stripping harvesting technique was evaluated at Röbäcksdalen in northern Sweden in mixed grass‐clover leys over 2 years. The PremAlfa Mini leaf stripper (Trust'ing‐Alf'ing, Nantes, France) worked well in mixed stands, harvesting on average a third of the available forage biomass, primarily in the form of leaves and soft stems from the clover plants. It proved successful in producing a forage fraction that had a significantly higher crude protein (CP) concentration (+39.1%) and lower neutral detergent fibre (aNDFom) concentration (−21.4%) than the pre‐harvest mixed sward (all significant at p &lt; .05 level). Due to the remaining high level of aNDFom in the leaf stripper fraction, it is more suited for use as an energy source for monogastrics rather than as a protein supplement. Alternatively, the leaf stripper fraction could be used to increase digestibility and CP content in the feed rations of high producing dairy cows.

Comparative Analysis of In Vitro Fermentation Parameters in Total Mixed Rations of Dairy Cows with Varied Levels of Defatted Black Soldier Fly Larvae (Hermetia illucens) as a Substitute for Soybean Meal

In this study, we compared the digestibility levels and in vitro fermentation parameters of total mixed rations (TMRs) containing 20% and 40% defatted black soldier fly (Hermetia illucens) larvae (BSF) as a substitute for soybean meal (SBM) in the basal ration (60% roughage/40% concentrated feed) of dairy cows. We evaluated the volatile fatty acid (VFA), total gas production, methane emission, ammonia, pH, carbon dioxide, in vitro dry matter digestibility (IVDMD), and neutral detergent fiber digestibility (IVNDFD) of the TMR0 (basal), TMR20 (20% BSF included), and TMR40 (40% BSF included) diets at the end of 24 and 48 h of incubation. Significantly lower levels of ammonia formation were found in the TMR20 and TMR40 groups at 24 and 48 h (p &lt; 0.001). An increase in total VFA levels was observed in the TMR0 group at 24 h (p &lt; 0.001). The highest IVDMD was determined in TMR20 and TMR40 at 24 h. The highest IVNDFD value was observed in TMR20 at 24 h and in TMR40 at 48 h. The substitution of 20% and 40% of SBM with BSF positively affected IVDMD and IVNDFD (p &lt; 0.001). TMR20 and TMR40 had the highest cumulative gas production at 48 h of incubation (p &lt; 0.05). In conclusion, the use of BSF had a positive impact on digestibility and in vitro rumen fermentation. Therefore, we recommend the use of BSF in formulating dairy cow rations.

Taking the diet of cows into consideration in designing payments to reduce enteric methane emissions on dairy farms

Enteric fermentation from dairy cows is a major source of methane. Significantly and rapidly reducing those emissions would be a powerful lever to mitigate climate change. For a given productivity level, introducing fodder with high sources of n-3 content, such as grass or linseed, in the feed ration of dairy cows both improves the milk nutritional profile and reduces enteric methane emissions per liter. Changing cows' diet may represent additional costs for dairy farmers and calls for the implementation of payments for environmental services to support the transition. This paper analyzes 2 design elements influencing the effectiveness of a payment conditioned toward the reduction of enteric methane emissions: (1) the choice of emission indicator capturing the effect of farmers' practices, and (2) the payment amount relative to the additional milk production costs incurred. Using representative farm-level economic data from the French farm accountancy data network, we compare enteric methane emissions per liter of milk calculated with an Intergovernmental Panel on Climate Change Tier 2 method, to baseline emissions from a Tier 3 method accounting for diet effects. We also quantify the additional milk production costs of integrating more grass in the fodder systems by estimating variable cost functions for different dairy systems in France. Our results show the relevance of using an emission indicator sensitive to diet effects, and that the significance and direction of the additional costs for producing milk with a diet containing more grass differ according to the production basin and the current share of grasslands in the fodder crop rotation. We emphasize the importance of developing payments for environmental services with well-defined environmental indicators accounting for the technical problems addressed, and the need to better characterize heterogeneous funding requirements for supporting a large-scale adoption of more environment-friendly practices by farmers.

Effects of forage and grain legume-based silages supplemented with faba bean meal or rapeseed expeller on lactational performance, nitrogen utilization, and plasma amino acids in dairy cows

The objective of this experiment was to investigate the effect of forage type [red clover (51%)-grass silage, i.e., RCG; vs. faba bean (66%)-grass silage, i.e., FBG] and concentrate type (faba bean, FB; vs. rapeseed expeller, RE) on lactational performance, milk composition and nitrogen (N) utilization in lactating dairy cows. Eight lactating multiparous Nordic Red cows were used in a replicated 4 × 4 Latin Square experiment, with 21-d periods, in a 2 × 2 factorial arrangement of treatments. The experimental treatments were as follows: (1) RCG with RE, (2) RCG with FB, (3) FBG with RE, and (4) FBG with FB. Inclusion rates of RE and FB were isonitrogenous. Crude protein contents of the experimental diets were 16.3, 15.9, 18.1, and 17.9% of dry matter, respectively. All diets included oats and barley and were fed ad libitum as total mixed rations with forage-to-concentrate ratio of 55:45. Dry matter intake and milk yield were recorded daily, and spot samples of urine, feces, and blood were collected at the end of each experimental period. Dry matter intake did not differ across diets, averaging 26.7 kg/d. Milk yield averaged 35.6 kg/d and was 1.1 kg/d greater for RCG versus FBG, and milk urea N concentration was lower for RCG compared with FBG. Milk yield was 2.2 kg/d and milk protein yield 66 g/d lower for FB versus RE. Nitrogen intake, urinary N, and urinary urea N excretions were lower, and milk N excretion tended to be lower for RCG compared with FBG. The proportion of the dietary N excreted as fecal N was larger in cows fed RCG than for those fed FBG, and the opposite was true for urinary N. We detected an interaction for milk N as percentage of N intake: it increased with RE compared with FB for RCG-based diet, but only a marginal increase was observed for FBG-based diet. Plasma concentration of His and Lys were lower for RCG than for FBG, whereas His tended to be greater and Lys lower for FB compared with RE. Further, plasma Met concentration was around 26% lower for FB than for RE. Of milk fatty acids, saturated fatty acids were decreased by RCG and increased by FB compared with FBG and RE, respectively, whereas monounsaturated fatty acids were increased by RCG versus FBG, and were lower for FB than for RE. In particular, 18:1n-9 concentration was lower for FB compared with RE. Polyunsaturated fatty acids, such as 18:2n-6 and 18:3n-3, were greater for RCG than for FBG, and 18:2n-6 was greater and 18:3n-3 was lower for FB versus RE. In addition, cis-9,trans-11 conjugated linoleic acid was lower for FB compared with RE. Faba bean whole-crop silage and faba bean meal have potential to be used as a part of dairy cow rations, but further research is needed to improve their N efficiency. Red clover-grass silage from a mixed sward, without inorganic N fertilizer input, combined with RE, resulted in the greatest N efficiency in the conditions of this experiment.

Winter cereal species, cultivar, and harvest timing affect trade-offs between forage quality and yield

Volatile feed costs and extreme weather events are contributing to greater economic risk and precarity throughout much of the United States dairy industry. These challenges have prompted dairy farmers to seek ways to reduce feed imports without compromising milk production. For organic dairy farmers, the need to produce more homegrown forage is exacerbated by the high cost and limited supply of organic feed. Integrating winter cereals for forage as part of a double-cropping system is a potential solution, but increasing the amount of forage in dairy cow rations can reduce milk production if the forages are not managed for optimal quality. Organically managed field experiments in Maryland (MD) and New York (NY) were conducted to address two primary objectives: (1) determine the yield and quality of winter cereals—four cultivars each for barley (Hordeum vulgare L.), cereal rye (Secale cereale L.), and triticale (× Triticosecale Wittm. ex A. Camus.)—grown as forage and harvested at different crop growth stages, and (2) evaluate the trade-offs between yield and quality in relation to winter cereal phenology and harvest date. Mean yield at a commonly harvested growth stage, swollen boot (Zadoks 45), was 1.3, 2.2, and 2.2 Mg ha−1 in MD and 1.8, 2.5, and 2.9 Mg ha−1 in NY for barley, cereal rye, and triticale, respectively. Mean relative forage quality (RFQ) at the same growth stage was 180, 158, and 163 in MD and 179, 156, and 157 in NY for the three species. Overall, cereal rye reached swollen boot stage the earliest, barley produced the highest RFQ and retained high quality the longest, and cereal rye and triticale produced the highest yields. Based on these results, farmers should consider barley cultivars if quality is the priority and winter-hardiness is not a concern; cereal rye cultivars if an early harvest is most important; and triticale cultivars if greater harvest schedule flexibility would be most valuable. These findings can be used to better meet the needs of dairy farmers, enhance double-cropping system performance, and improve the synchronization of harvest timing with the specific needs of lactating dairy cows, dry cows, heifers, and calves.

The use of propyleneglycol for the prevention of ketosis of cows in the fresh period

Relevance. Prevention of ketosis in freshly calved cows is one of the urgent problems in the industry. The article presents data on the results of the use of propyleneglycol in the diets of cows during the transit period.Methods. For the study, 2 groups of cows were formed, control and experimental, with 30 heads each. The cows of the control group were fed the rations for dry and dairy cows of the highly productive group adopted on the farm. Cows of the experimental group in the dry period two weeks before calving in addition to the diet of the control group got 150 g of propyleneglycol per head per day and for two weeks after calving — 250 g.Results. It was found that the addition of propyleneglycol to the diets of cows for two weeks before calving and four — after — turned out to be expedient in the prevention of ketosis during the milking period. Analysis of milk for the presence of ketone bodies using test strips on the 10th day of lactation revealed positive results in 10% of cows in the control group, while 17% of cows were at risk. Analogical studies conducted on the 30th and 60th days of lactation showed the presence of ketone bodies in 7 and 3% of cows of the control group respectively, with questionable results in 6 and 4%. At the same time, in cowsof the experimental group, receiving propyleneglycol, this analysis did not show signs of ketosis.

Populasi Mikroba Rumen, Fermentabilitas, dan Kecernaan Suplementasi Daun Kelor dalam Ransum Sapi Perah secara In Vitro

This study aimed to evaluate the microbial rumen population, fermentability, and digestibility of Moringa leaf supplementation in dairy cow ration using in vitro and to determine the optimal level of supplementation. The experiment consist of two steps with the first step was microbiology measurement used a Randomized Block Design with 5 treatments level of Moringa leaf extract (P0= control; P1= 5%, P2 = 10%, P3 =15%, P4 =20%) and the second step was in vitro fermentability and digestibility measurement used Randomized Block Design with 7 treatments level of Moringa leaf in dairy cow ration (R0 = control, R1 = R0 + 2.5% Moringa leaf, R2= R0 +5% Moringa leaf, R3 = R0 + 7.5% Moringa leaf, R4= R0+10% Moringa leaf, R5=R0+12.5% Moringa leaf, R6=R0+15% Moringa leaf) which grouped by rumen fluids. Data analysis used analysis of variance and continued with Duncan’s Multiple Range Test. The measured variable were microbial rumen population (bacteria and protozoa), fermentability (N-NH3, VFA), microbial protein synthesis, dry matter digestibility (DMD), and organic matter digestibility (DMO). The results showed Moringa leaf extract significantly decreased bacterial population (p&lt;0.05), but there was no effect on the protozoa population. Moringa leaf supplementation did not affect N-NH3, DMD, and DMO, but significantly influenced VFA concentration and microbial protein synthesis (p&lt;0.01). The higher Moringa leaf supplementation showed decreasing total VFA concentration, but was still within the normal range for rumen fermentation (102.29-126.69 mM). Moringa leaf supplementation showed a quadratic effect on microbial protein synthesis with an optimal supplementation level of 5%, but decreasing at a level of 7.5% still within in normal range. It can be concluded Moringa leaf can be supplemented up to 7.5% in dairy cow ration.&#x0D; Key words: digestibility, fermentability, in vitro, moringa leaf, dairy cow

Combined Inclusion of Former Foodstuff and Distiller Grains in Dairy Cows Ration: Effect on Milk Production, Rumen Environment, and Fiber Digestibility.

The aim of the present study was to investigate the effect of the substitution, in dairy cow rations, of traditional protein and starch sources with more sustainable "circular" feeds to increase the sustainability of dairy production. For this purpose, eight multiparous mid-lactating cows were blocked and assigned to one of four treatments and were used in a replicated 4 × 4 Latin squares design with 21-days periods (14 days of adaptation and 7 of data collection). Two different circular feedstuffs were tested: a bakery's former foodstuff (FF) and a wheat distiller's grain with solubles (WDGS). These ingredients were used, alone and in combination, in three experimental diets (FF, WDGS; FF + WDGS) and compared to a standard ration (CTR). Dry matter intake and rumination time were not influenced by these diets. Conversely, dietary treatments partially influenced the milk yield, rumen pH, Volatile Fatty Acids (VFA) production, and fibre digestibility. In particular, the combined inclusion of FF and WDGS increased milk production (37.39 vs. 36.92, 35.48, 35.71 kg/day, for FF, WDGS and CTR diets, respectively) and reduced milk urea content (13.14 vs. 16.19, 15.58, 16.95 mg/dL for FF, WDGS, and CTR diets, respectively). No effects of this association were found in the milk composition, acetic and propionic production, and fibre digestibility. These results suggest that the association of former foodstuff and wheat distillers' grains could be safely included in dairy cow rations to increase the sustainability of cow nutrition and improve milk production without impairing animal health, dry matter intake, and fibre digestibility.