Fat-corrected Milk Research Articles

Effect of a Bacillus subtilis-based direct-fed microbial, on milk yield, milk components, feed intake and plasma hormones and metabolites in lactating Holstein cows

To investigate the effects of a Bacillus-based direct-fed microbial on milk production and related factors, a study was conducted on Holstein cows (n = 28) starting at 90 ± 11 DIM. The cows were divided into two dietary groups: a control group (CON) that received a total mixed ration (TMR), and a Bacillus-fed group (DFM) that received the same TMR along with a Bacillus subtilis product containing two strains (747 and 1781) in equal amounts. The study lasted for 25 wk and included both primiparous and multiparous cows. The cows were housed in a free-stall barn and were provided with ad libitum TMR, which was fed twice a day. Their daily meals and dry matter intake (DMI) were recorded during wk 1–4 and wk 19–25 using electronic feeders. Milk samples were collected weekly during morning and evening milkings and analyzed for milk fat, protein, lactose, and milk urea nitrogen (MUN). Blood samples were also collected weekly and analyzed for plasma glucose, insulin, cholesterol, insulin-like growth factor 1 (IGF1), and progesterone concentrations. Additionally, rumen fluid samples were collected and evaluated for various species of bacteria. One of the key findings was that daily 4 % fat-corrected milk production (FCM) was influenced by the interaction between treatment (DFM vs. CON) and parity (primiparous vs. multiparous), with multiparous DFM cows producing 11 % more FCM compared to CON. The DFM cows also had a higher milk fat percentage (4.41 % vs. 4.02 %) and MUN concentrations were 1.0 mg/dL higher in the DFM group. In terms of blood metabolites and hormones, multiparous DFM cows had lower plasma cholesterol, glucose, and insulin concentrations compared to CON multiparous cows. However, there were no significant differences between the groups in terms of plasma IGF1 concentrations, insulin-to-glucose ratios, and luteal phase plasma progesterone concentrations. The analysis of rumen fluid samples revealed that the abundance of Ruminococcus albus and Fibrobacter succinogenes group I was greater in the DFM cows compared to CON cows. Furthermore, during the periods when feed intake was measured, the DFM cows had a 9 % reduction in feed intake and a 14 % improvement in feed efficiency (FCM per DMI) compared to CON cows. In conclusion, the two-strain Bacillus product used in this study (Certillus) showed potential as an effective direct-fed microbial. It was found to increase feed efficiency and milk production by altering the composition of ruminal microbiota and metabolism in the cows.

Effect of feeding two types of concentrates in morning and evening meals and two types of fat supplement on diurnal patterns of plasma parameters in lactation dairy cows

The diurnal patterns of feed intake and TMR composition influence blood parameters in dairy cows; however, the effect of feeding TMR with different compositions in the morning and evening meals is not well characterized. In a completely random design, forty Holstein cows (110 ± 30 days postpartum) were randomly assigned to four treatment groups, with 10 cows per treatment. The treatments were as follows: a base diet containing 50 % cereal starch from barley grain and 50 % cereal starch from corn grain in the morning and evening meal + either prilled fatty acids supplement (EqP) or calcium salts of fatty acids supplement (EqCS); a base diet containing 25 % cereal starch from barley grain, 75 % cereal starch from corn grain in the morning meal, and 75 % cereal starch from barley grain and 25 % cereal starch from corn grain in the evening meal + either prilled fatty acids supplement (DiP) or calcium salts of fatty acids supplement (DiCS). Dry matter intake was affected by treatments (P ˂ 0.01). The highest intake was observed for EqP, EqCS, DiP,and DiCS. 3.5 % fat-corrected milk and milk fat percentage was significantly higher for EqP than other treatments (P ˂ 0.01), but other milk components were not significantly different among treatments (P ˃ 0.05). A significant difference was observed for glucose, cholesterol, TG, AST, and insulin concentration among treatments (P ˂ 0.01). The concentrations of all plasma parameters (glucose, cholesterol, TG, BUN, AST, insulin, and NEFA) significantly changed over 24-h period (P ˂ 0.01). Plasma concentrations of glucose, cholesterol, TG, BUN, AST, insulin, and NEFA displayed a treatment-by-time interaction (P ˂ 0.01). In general, changes in the cereal starch ratio (corn and barley) in TMR in each meal during a day affect the 24-h concentration of plasma parameters, but there was no strong evidence of leverage for cows’ metabolism.

Lactational performance of dairy buffaloes affected by replacing soybean meal with an alternative microbial protein source

Thirty dairy buffaloes were used for 90 days to evaluate the impact of a novel protein source (HI-PRO®), a feed alternative rich in protein (made from Saccharomyces and Bacillus), on the productivity of nursing buffaloes. The nursing water buffaloes had an average weight of 550 ± 11.2 kg. The treatments consisted of diets containing two distinct protein sources: (1) soybean meal (44 % as the control group); and (2) HI-PRO® product. Throughout the trial, measurements of nutritional digestibility and blood metabolites (total protein, albumin, urea, and creatinine) were conducted. Quantity and composition of the milk were measured to determine the content of milk proteins, lipids, and lactose. The outcome of the results showed insignificant decrease in the buffaloes receiving HI-PRO® feed versus control group. Furthermore, there was enhancement in the fiber digestibility by approximately 2.5 % in the HI-PRO® group compared to the control group. The levels of protein, albumin, globulin, urea, and creatinine fall within the normal range for animals in good health. Using HI-PRO® resulted in a marginal improvement in milk production, increasing it by approximately 4.8 % compared to soybean meal. Furthermore, the buffaloes fed HI-PRO® showed a slightly elevated 4 % fat-corrected milk output and milk composition. To summarize, nursing buffaloes can utilize HI-PRO® as an efficient protein source in their diets, replacing soybean meal.

Somatic Cell Count Evaluation in Early Lactation Betweenprimiparous and Multiparous Bos indicus Cows (SDG'S)

Objective: A study examined the relationship between somatic cell count (SCC) and milk yield Theoretical Framework: The sustainable development of dairy farms will be key to stopping the growing agricultural frontier. In comparison to breeds from temperate regions, tropical bovine production is low in terms of milk kilos, composition, or udder health. Method: We enrolled one hundred fifty cows (Primiparous, PM, 75 and Multiparous, MP 75) in early lactation (days in milk, PM =134 ± 3; MP = 136 ± 5), milk production (9,88 kg/d, on average) of the creole breed Gyr lechers. Prior to the assignment to each treatment, the SCC values were lower than 220,000 cells/mL, on average. All cows were maintained to graze daily on Megathyrsus maximus and supplemented with Morus alba ad libitum, being hand-milking at 0700 daily. Before analysis, the SCC was logarithmically trans-formed (log10). Then, PROC Mixed from SAS version 9.4 was used to evaluate all measurements. Results and Discussion: The MP had higher milk yields than PM cows (10.83 vs. 9.18 ± 0.38 kg/d; P = 0.003). Similar results were observed for fat-corrected milk (8.26 vs. 6.80 ± 0.34; P = 0.002), although the fat values did not differ between both groups (P = 0.86) being lower than referential values for these breeds (2.46 ± 0.16, on average). Additionally, no differences were observed in the other milk components (P = 0.65 to 0.85). Despite that, the somatic cell count (SCC) values indicated a statistical tendency in PM than in MP (1.89 vs. 2.13 ± 0.05; P = 0.07). Research Implications: Low-fat contents were observed in both groups, possibly due to the low quality of foods used in ruminant feeding. Correspondingly, the parity and advanced lactation conditioned the SCC contents. Therefore, further studies may be relevant in order to identify complementary factors that possibly could be more determinants. Originality/Value: The relevance and value of this research are very importance due to the main activity in this zone is livestock cattle.

Mammary gland responses to altering the supply of de novo fatty acid substrates and preformed fatty acids on the yields of milk components and milk fatty acids

The objective of our study was to evaluate the effect of altering the dietary supply of acetate, palmitic acid (PA), and cottonseed on the yields of milk components and milk fatty acids (FA) in lactating dairy cows. Thirty-two multiparous Holstein cows (133 ± 57 d in milk, 50.5 ± 7.2 kg/d milk) were used in a 4 × 4 Latin square split plot design with a 2 × 2 factorial arrangement of subplot treatments. Cows were blocked by energy-corrected milk (ECM) yield and allocated to a main plot receiving a basal diet (n = 16) with no supplemental PA (Low PA) or a basal diet (n = 16) with 1.5% inclusion of a FA supplement containing ~85% PA (High PA). In each main plot, the following subplots of treatment diets were fed in a Latin square arrangement consisting of 14-d periods: 1) a control diet (CON), 2) the control diet supplemented with 3% sodium acetate (AC), 3) the control diet supplemented with 12% whole cottonseed (CS), and 4) the control diet supplemented with 3% sodium acetate and 12% whole cottonseed (CS+AC). The PA supplement and sodium acetate replaced soyhulls, and whole cottonseed replaced cottonseed hulls and meal. All diets were balanced for 30% neutral detergent fiber (NDF), 23% forage NDF, 28% starch, and 17% crude protein (CP). Sources of FA were classified as de novo (<16 carbons), mixed (16-carbon), and preformed (>16 carbons). The statistical model included the random effect of cow nested within basal diet and fixed effect of period, basal diet, acetate, cottonseed, and their interactions. Three-way interactions among basal diet, acetate, and cottonseed were observed for the yields of milk fat, 3.5% fat-corrected milk (FCM), and the molar yields of de novo FA, mixed FA, and preformed FA. In the Low PA diets, AC and CS+AC increased the yields of milk fat and FCM compared with CON and CS, whereas, in the High PA diets, CS+AC increased the yields of milk fat and FCM compared with the other treatments and AC increased milk fat yield compared with CON and CS. Compared with Low PA, High PA increased milk fat content, mixed FA yield, and tended to increase C4:0 yield. Diets containing acetate increased DMI and the yields of milk fat, ECM, FCM, de novo FA, mixed FA, and preformed FA compared with diets without acetate. Diets containing cottonseed increased the yields of milk and preformed FA, tended to increase the yields of FCM and protein, and decreased DMI and the yields of de novo FA and mixed FA compared with diets without cottonseed. In summary, in high PA diets, the inclusion of acetate plus cottonseed increased milk fat yield compared with the other treatments. The CON diet in High PA increased milk fat yield to the same extent as AC and CS+AC in Low PA suggesting PA is important for initiating milk TG synthesis. Balancing the supply of de novo FA substrates and preformed FA is important for increasing the synthesis of milk fat triglycerides and milk fat production.

Sustainable Livestock Farming with Oil Seed Crops and Their By-Products

The increasing human population and food shortage are fueling the demand for alternative feed resources for animals not meant for human consumption. Oil seeds and their derivatives are suitable options to meet the escalating global demand for animal feed proteins; camelina is one of them. Camelina sativa (CS), an ancient oilseed crop belonging to the Brassicaceae family, is known for its resistance to drought and cold, as well as its various uses for meal, oil, and other products. However, it also has some anti-nutritional factors (ANF) that can limit its use as animal feed. These ANFs can be reduced by various methods, such as enzyme addition, heat treatment, fermentation, or genetic engineering. CS and its by-products can affect animal metabolism, especially lipid metabolism and hormone levels, and can also improve the fat profile of meat and milk products, making them more suitable for human consumption and health. CS and its by-products achieved weight gain and protected dietary PUFAs, but decreased bio-hydrogenation intermediates. Small ruminants fed CS-supplemented diets produced meat with a suitable fat profile for human consumption. Feeding with CS seeds and derivatives decreased milk fat concentration, yield, and fat-corrected milk. Camelina forage, however, increased the milk fat percentage. The effects of CS and its by-products on milk fatty acid composition were contradictory. CS meals may improve the composition of milk products, making them healthier for humans. Researchers need to determine how CS meals can be used in dairy ewe and goat diets at different life stages.

Effects of postbiotic products from Saccharomyces cerevisiae fermentation on lactation performance, antioxidant capacities, and blood immunity in transition dairy cows

This study aimed to evaluate the effects of dietary supplementation with different types of Saccharomyces cerevisiae fermentation products (SCFP) on lactational performance, metabolism, acute phase protein response, and antioxidant capacities in dairy cows from -21 to 56 d in milk (DIM). One hundred and 80 multiparous Holstein dairy cows were blocked by parity, expected calving date, pre-trial body condition score, and previous 305-d ME yield, and then randomly assigned to 1 of 3 dietary treatments: basal diet (CON; n = 60), basal diet supplemented with 40 g/d of SCFP1 (XPC; n = 60; XPC, Diamond V, Cedar Rapids, IA), and basal diet supplemented with 19 g/d of SCFP2 (NTK; n = 60, NutriTek®, Diamond V, Cedar Rapids, IA). Blood (n = 15, 13 and 12 in the CON, XPC and NTK groups, respectively) was sampled at -7 ± 3, + 3, + 7, + 21, and + 28 d, and milk samples (n = 19, 18 and 15 in the CON, XPC and NTK groups, respectively) was sampled during 1-8 wk from a subset of cows from -21 to 56 d relative to calving. Data were analyzed using the MIXED procedure in SAS (SAS Institute Inc.). All data were subjected to repeated measures ANOVA. Dietary treatment (TRT), time, and their interaction (TRT × time) were considered as fixed effects and cow as the random effect. Cows fed XPC and NTK had greater energy-corrected milk (ECM). Supplementing NTK increased milk fat content and yield, and 3.5% fat-corrected milk (FCM) yield compared with CON. Milk urea nitrogen (MUN) was lower in XPC cows than CON. SCFP supplementation decreased plasma β-hydroxybutyrate (BHB), ceruloplasmin (CER), haptoglobin (HPT), and interleukin-1β (IL-1β) concentrations, whereas increased plasma phosphorus (P) concentrations. In addition, cows fed NTK showed lower creatinine (CR) and cortisol (COR) concentrations but increased plasma calcium (Ca) and myeloperoxidase (MPO) concentrations than those in the CON cows. In addition, cows fed NTK and XPC both had reduced plasma concentrations of serum amyloid-A (SAA) at 3 DIM of lactation compared with CON fed cows. Furthermore, SCFP cows had greater concentrations of plasma glucose (GLU) and calcium (Ca) than CON cows at 7 DIM, and greater concentrations of plasma phosphorus (P) at 21 DIM. Between different SCFP type fed groups, plasma concentrations of nonesterified fatty acids (NEFA), MDA, creatinine (CR), SAA, and HPT were lower in cows fed NTK compared with cows fed XPC at 7 DIM. Overall, our results indicate the potential benefits of supplementing SCFP in transition dairy cows by modulating immunity, liver metabolic function and supporting ECM yield. The results also suggest that NutriTek at 19 g/d appears to support the performance and health of dairy cows better compared with XPC at 40 g/d, based on improved metabolic and inflammatory status during the transition period.

Potential use of pineapple crop residue silage to replace sorghum silage for crossbred lactating cows

The use of crop residue silages is a viable alternative for producers to reduce feed costs. The present study was developed with the objective of investigating the inclusion of pineapple silage in replacement of sorghum silage in the diet of lactating cows regarding feed intake, production, and quality of milk. Eight crossbred (Holstein × Gir) cows with an average weight of 555±30 kg and an average milk yield of 12.50±3.25 kg/day, between 60 and 90 days in milk, were distributed into two simultaneous 4 × 4 Latin squares, at one animal per experimental unit. Silage of pineapple crop residue (PS) using plants after the harvest of the fruits was included in the roughage portion of the diet at increasing levels, with simultaneous and proportional removal of sorghum silage (SS) from the diets. The studied treatments thus consisted of the roughage portion containing: 1- 0% PS and 100% SS (100SS); 2- 34% PS and 66% SS (34PS66SS); 3- 67% PS and 33% SS (67PS33SS); 4- 100% PS and 0% SS (100PS). The diets were supplied twice daily, allowing 5% leftovers in relation to the quantity offered. The amounts of feed supplied, and orts of each animal were weighed for a subsequent determination of intake. The experiment was divided into four 21-day sub-periods, the first 14 days of which were used as an adaptation to the diet, while the others served for data collection. The milk was weighed from the 15th to the 19th day of each experimental period, and milk samples were collected on the last day of each period. Milk samples were sent to the laboratory, where they were analyzed. Dry matter, mineral matter, and lignin concentrations in the diet did not vary (P&gt;0.05) as a function of PS inclusion in the roughage portion, while protein content, fiber content, and fat content levels were influenced. No effect of PS inclusion was observed (P&gt;0.05) on the intakes of dry matter, neutral detergent fiber, mineral material, or lignin. However, PS inclusion prompted (P&lt;0.05) a linear increase in the intakes of protein and total fat. The inclusion of pineapple plant silage in the roughage part of the diet had a positive effect (P&lt;0.05) on milk yield, 4% fat-corrected milk yield, and on the milk fat and total solids contents. Milk production, as well as fat and total solids content, increased moderately with inclusion of pineapple plant silages in the roughage portion of the diet. Therefore, pineapple silage can replace sorghum silage in the roughage part of diets for lactating crossbred cows.

Heat stress has divergent effects on the milk microbiota of Holstein and Brown Swiss cows.

Heat stress (HS) is one of the pivotal causes of economic losses in dairy industries and affects welfare and performance, but its effect on milk microbiota remains elusive. It is also unclear if and how different breeds may cope with HS in sustaining productive performance. The objectives of this study were to compare a) the performance of 2 dairy breeds, namely Holstein and Brown Swiss, subjected to HS and b) the different effects of HS on the milk microbiota of the 2 breeds in thermal comfort conditions and HS. The study was carried out on 36 dairy cows, 18 per breed. The HS was induced by switching off the cooling system during a natural heat wave for 4 d. Besides the Temperature Humidity Index (THI), the animal stress was confirmed by measuring respiratory frequency and rectal temperature twice daily at 4 a.m. and 3 p.m. The HS differently impacted the 2 breeds. Rectal temperatures were higher in Holstein cows, while no changes in rectal temperature were found in Brown Swiss. Milk yield recording and sampling were performed during the morning milking of d 1 (at 4.00 a.m.) and afternoon milking of d 4 (at 5.00 p.m.). Productive parameters were also different: milk yield, fat-corrected milk, energy-corrected milk, protein and casein content, and renneting parameters were decreased in Holstein but remained unaffected in Brown Swiss. The HS also modified the milk microbiota of the 2 breeds differently. During HS, the Brown Swiss milk microbiota was richer (α diversity) than the Holstein one. Comparing the time points before and during HS within breeds showed that Brown Swiss milk microbiota was less affected by HS than Holstein's. Under the same thermal comfort condition, milk microbiota did not discriminate between Brown Swiss and Holstein. Consistently with α and β diversity, the number of operational taxonomic units (OTUs) at the genus level that changed their abundance during HS was higher in Holstein (74 OTUs) than in Brown Swiss (only 20 OTUs). The most significant changes in abundance affected Acinetobacter, Chryseobacterium, Cutibacterium, Enterococcus, Lactococcus, Prevotella-9, Serratia, and Streptococcus. In conclusion, the present report confirms and extends previous studies by demonstrating that Brown Swiss cows regulate their body temperature better than the Holstein breed. The relative thermal tolerance to HS compared with Holstein is also confirmed by changes in milk uncultured microbiota, which were more evident in Holstein than in Brown Swiss.

Co-ensiled rice straw with whole sugar beet and its effect on the performance of lactating cows

This study investigated the effect of co-ensiled rice straw (RS) with whole sugar beet (SB) on lactating cows’ performance. Ensiled rice straw (ERS) as control (CGS) was incorporated with immersed corn grains (CG) for 24 h, while the 2nd and 3rd ensiled RS (LSB and HSB) contained SB substituted of 50 and 100% of CG on an energy basis (total digestible nutrients, TDN), respectively. In the experimental diets, D1, D2, and D3, which include CGS, LSB, and HSB provided ad-libitum, respectively, while a concentrated feed mixture (2% of body weight) was offered. The population of lactic acid bacteria was slightly higher with fed HSB, relative to LSB and CGS. The OM, CP, EE, NFC, and TCH contents of CGS were slightly higher than LSB and HSB, while the opposite happened with the aNDFom, and ADFom contents. The digestibility of DM, OM, aNDFom, and ADFom of the D3 group was higher (P < 0.05) than in D1 and D2. The D3 recorded the highest values (P < 0.05) of silage consumption, and palatability. Milk production, fat-corrected milk (FCM), and energy-corrected milk (ECM) were (P < 0.05) higher for cows fed D3 compared with D1 and D2. Fat, protein, lactose, and total solids were trending on the same track. The feed conversion ratio (FCR) of cows fed diet D3 was better than cows fed D1 diet. The level of glucose in the blood increased (P < 0.05) significantly with feeding on HSB than LSB, which was significantly (P < 0.05) higher compared to CGS. In conclusion, co-ensiling of RS with the whole SB plant consider a good method to improve its nutritional value.

Effects of prilled fat supplementation in diets with varying protein levels on production performance of early lactating Nili Ravi Buffaloes.

The objective of the current study was to find out the independent and interactive effects of prilled fat supplementation with protein on the production performance of early lactating Nili Ravi buffaloes. Sixteen early lactating buffaloes (36.75±5.79 d in milk; mean±standard error) received 4 treatments in 4×4 Latin-square design according to 2×2 factorial arrangements. The dietary treatments were: i) low protein low fat, ii) low protein high fat, iii) high protein low fat, and iv) high protein high fat. The dietary treatments contained 2 protein (8.7% and 11.7% crude protein) and fat levels (2.6% and 4.6% ether extract) on a dry matter basis. The yields of milk and fat increased with increasing protein and fat independently (p≤0.05). Energy-, protein-, and fat-corrected milk yields also increased with increasing protein and fat independently (p≤0.05). Increasing dietary protein increased the protein yield by 3.75% and lactose yield by 3.15% and increasing dietary fat supplies increased the fat contents by 3.93% (p≤0.05). Milk yield and fat-corrected milk to dry matter intake ratios were increased at high protein and high fat levels (p≤0.05). Milk nitrogen efficiency was unaffected by dietary fat (p>0.10), whereas it decreased with increasing protein supplies (p≤0.05). Plasma urea nitrogen and cholesterol were increased by increasing protein and fat levels, respectively (p≤0.05). The values of predicted methane production reduced with increasing dietary protein and fat. It is concluded that prilled fat and protein supplies increased milk and fat yield along with increased ratios of milk yield and fat-corrected milk yields to dry matter intake. However, no interaction was observed between prilled fat and protein supplementation for production parameters, body weight, body condition score and blood metabolites. Predicted methane production decreased with increasing protein and fat levels.

Lactation performance, feed efficiency, and blood metabolites of dairy cows treated with recombinant bovine somatotropin: A systematic review and meta-analysis

A systematic review and meta-analysis were conducted to assess the impact of recombinant bovine somatotropin (rbST) on lactation performance, feed efficiency, and blood metabolites in dairy cows. In the systematic review, articles were selected based on the following criteria: (1) Data focusing on the influence of bovine somatotropin doses on milk production; (2) Submission of original data; (3) Articles published in journals; and (4) Articles in English or Portuguese. The analysis of variance was used with a completely randomized design and mixed models methodology. Polynomial regression was applied to significant fixed effects (rbST dose). The use of rbST resulted in increased milk yield and 4% fat-corrected milk yield, while fat, protein, and lactose contents remained unaffected. Dry matter and metabolizable energy intakes, as well as milk/feed efficiency, exhibited a linear increase, but body condition score (BCS) was negatively impacted. The administration of rbST led to higher blood concentrations of triglycerides and insulin. Cows treated with rbST showed a 23% increase in non-esterified fatty acid (NEFA) concentrations compared to non-treated cows. Additionally, growth factors IGF-1 and IGF-2 displayed a linear increase with rbST treatment. In summary, rbST administration increased milk yield and fat-corrected milk yield without affecting milk components. However, despite increasing intake, it resulted in BCS losses and alterations in blood parameters such as NEFA, IGF-1, and IGF-2.

Supplementation of critical micro-nutrients in peri‑parturient dairy buffaloes improves lactation performance

BackgroundThe peri‑parturient period is the most vital period of a dairy animal's life and affects its future performance. Dairy animals get exposed to severe metabolic stress during the peri‑parturient period and their stress tolerance capacity during the period remains a key factor to harvest optimum production from these animals without getting exposed to any of peri‑parturient disorders. The study aimed to evaluate the effect of weekly critical micro-nutrient (CMN) supplementation during the periparturient period on the lactation performance of Murrah buffaloes. MethodsWeekly CMN (vitamins E, A, and niacin with minerals Co, Cr, Cu, Se, and Zn) supplementation during the periparturient period (56 days prepartum, till 56 days post-partum) was performed on twenty-two healthy Murrah buffaloes during their advanced stage of gestation following dividing them into two groups of 11 buffaloes in each group, representing control and supplemented (Treatment) groups. Buffaloes were selected and sustained on recommended practices of feeding as per nutrient requirements, except the inclusion of CMN supplement once a week in the treatment group's buffaloes after proper mixing with common concentrate mixture being fed to buffaloes. Weekly milk production recording was carried out with analysis of milk quality parameters, for an initial 10 weeks of the lactation. ResultsThe treatment helped in improving the milk production record of buffaloes; total milk yield by 18 % and fat-corrected milk by 30 % (P < 0.05). It leads to qualitative improvement as well (percentage of milk fat and protein, P < 0.05). ConclusionIt may be concluded that weekly supplementation of critical micronutrients during the periparturient period helps improve buffalo milk production performance.

Effects of supplementing cassava root silage to grazing dairy cows on nutrient utilization, milk production and composition in the tropics.

The current study evaluated the effects of supplementing cassava root silage (CRS) to dairy cows grazing on Megathyrsus maximus cv Mombasa on nutrient intake and digestibility, as well as on milk production and composition. Ten primiparous Girolando cows with average body weight ± (SEM) of 373.45 ± (63.55) kg were used in a replicated 5 × 5 Latin square. Animals were subjected to five treatments: (I) grazing cows without supplementation (WCS); (II) grazing cows provided with 5kg DM of supplement without CRS (0g/kg DM of CRS) or including (III) 260, (IV) 520, and (V) 780g/kg DM of CRS. Statistical analyses were performed using the PROC MIXED of SAS with significance at P < 0.05. Intake of neutral detergent fiber (NDF) and ether extract decreased (P < 0.01), while intake of non-fiber carbohydrates increased (P < 0.01), with increased CRS in the diets. Total DM intake and digestibility of DM, and digestibility of nutritional components were lower (P < 0.03) in WCS animals compared to supplemented animals, except for intake and digestibility of NDF, which was the opposite. Milk yield (MY) and fat corrected milk (FCM), as well as all milk components were unaffected (P > 0.05) by CRS inclusion. In contrast, MY, FCM, protein, lactose, casein, and non-fat milk solids (NFMS) were greater for animals that received supplementation (P < 0.05), compared to animals WCS. Milk fat and total dry extract (TMS) did not differ (P > 0.11) between two groups. In conclusion, CRS may be a potential corn meal replacer in the supplement of dairy cows under tropical conditions.

Effects of high moisture ear corn on production performance, milk fatty acid composition, serum antioxidant status, and immunity in primiparous dairy cows.

This study evaluated the effects of high moisture ear corn (HMEC) on production performance, milk fatty acid composition, serum antioxidant status, and immunity in primiparous dairy cows. A total of 45 healthy primiparous Holstein cows (36.50±4.30 kg of milk/d, 201±9.00 lactating days in milk) were sorted into 3 groups: control group (CG, n = 15); 50% HMEC (replacing 50% steam-flaked corn with HMEC, n = 15); and 100% HMEC (replacing steam-flaked corn with HMEC, n = 15) on an equal dry matter (DM) basis. The study consisted of adaptation period of 14 days, followed by a formal period of 60 days. Feed intake and milk yield were recorded daily. Milk and blood samples were collected on 1, 30, and 60 d of the experimental period. The 50% HMEC group and 100% HMEC group significantly increased (p<0.05) milk yield and DM intake in dairy cows compared to the control group (CG). The 100% HMEC group showed an increase (p<0.05) in 4% fat-corrected milk (4% FCM). Both the 50% HMEC group and 100% HMEC group exhibited significant decreases (p<0.05) in the content of C10:0, C12:0, and C14:0 fatty acids, along with a significant increase (p<0.05) in cis-9C18:1 content. The saturated fatty acid content was significantly lower (p<0.05) in the 50% HMEC and 100% HMEC groups than that of CG. Conversely, the monounsaturated fatty acid content was higher (p<0.05) in the 50% HMEC and 100% HMEC groups than that in CG. Notably, the 100% HMEC group significantly increased (p<0.05) the serum superoxide dismutase and glutathione peroxidase content, while also decreasing the serum malondialdehyde content (p<0.05). Moreover, the 100% HMEC group significantly increased (p<0.05) the content of immunoglobulin G (IgG) and IgM. High moisture ear corn could improve production performance and milk fatty acid levels and enhance immunity and antioxidant capacity in dairy cows. These results lay the foundation for the wider application of HMEC in ruminant animal diets.

Rumen-Protected Choline Improves Metabolism and Lactation Performance in Dairy Cows.

Choline is required for the synthesis of phosphatidylcholine, an important constituent of lipoproteins. Early lactation cows presumably synthesize insufficient phosphatidylcholine, and choline supplementation in a rumen-protected form might benefit metabolism and lactation. The objectives of this study were to determine the effects of feeding rumen-protected choline (RPC) on lactation and metabolism in dairy cows. In experiment 1, 369 nulliparous and parous Holstein cows housed in four pens per treatment were fed 12.9 g/day of choline as RPC from 25 days prepartum until 80 days postpartum. In experiment 2, 578 nulliparous cows housed in five pens/treatment were fed 12.9 g/day of choline as RPC in the last 22 days of gestation only. In both experiments, blood was sampled and analyzed for concentrations of nonesterified fatty acids (NEFAs) and glucose at 1, 14, and 21 days postpartum and of choline at 1 and 14 days postpartum. Blood from all cows was sampled and analyzed for concentrations of β-OH butyrate (BHB) at 1 and 14 days postpartum. Cows with BHB > 1.2 mmol/L were classified as having hyperketonemia. Hepatic tissue was collected from 46 cows from the eight pens in experiment 1 at 9 days postpartum and analyzed for concentrations of glycogen and triacylglycerol. Milk yield and components were measured for 80 days postpartum in experiment 1, whereas only milk yield was measured in experiment 2. The pen was the experimental unit of analysis. Supplementing RPC tended to increase dry matter intake (DMI) prepartum in experiments 1 and 2 and postpartum in experiment 1. Feeding cows with RPC increased yields of 3.5% fat-corrected milk (42.8 vs. 44.8 kg/day), energy-corrected milk (38.5 vs. 40.3 kg/day), milk fat (1.52 vs. 1.61 kg/day), and true protein (1.16 vs. 1.21 kg/day) in experiment 1. Milk yield tended to be greater with RPC (26.4 vs. 27.4 kg/day) in experiment 2. Supplementing RPC increased plasma choline concentrations on day 14 postpartum in experiment 1 (3.32 ± 0.27 vs. 4.34 ± 0.28 µM) and on day 1 in experiment 2 (3.35 ± 0.16 and 13.73 ± 0.15 µM). Treatment did not affect the concentrations of glucose, NEFAs, or BHB in plasma, but the incidence of hyperketonemia was less in multiparous cows fed RPC than those fed the control in experiment 1. Feeding cows with RPC reduced hepatic triacylglycerol content and tended to reduce the ratio of triacylglycerol to glycogen and the risk of hepatic lipidosis in cows in experiment 1. The concentrations of hepatic triacylglycerol on day 9 postpartum were inversely related to those of choline in plasma on day 1 postpartum. Feeding cows with RPC improved lactation and metabolism, but more benefits were noted when it was fed before and after calving.

Somatic Cell Count Evaluation in Early Lactation between Primiparous and Multiparous Bos indicus Cows

Using Bos indicus cows, a study examined the relationship between somatic cell count (SCC) and milk yield. For this study, one hundred fifty cows (Primiparous, PM, 75 and Multiparous, MP 75) in early lactation (days in milk, PM =134 ± 3; MP = 136 ± 5), milk production (9,88 kg/d, on average) of the creole breed Gyr lechers were enrolled. Before being assigned to each treatment, the SCC values were lower than 220,000 cells/mL, on average. All cows were maintained to graze daily on Megathyrsus maximus and supplemented with Morus alba ad libitum, being hand-milking at 0700 daily. Before analysis, the SCC was logarithmically transformed (log10). Then, PROC Mixed from SAS version 9.4 was used to evaluate all measurements. Regarding our results, the MP had greater milk yields than PM cows (10.83 vs. 9.18 ± 0.38 kg/d; P = 0.003). Similar results were observed for fat-corrected milk (8.26 vs. 6.80 ± 0.34; P = 0.002), although the fat values did not differ between both groups (P = 0.86) being lower than referential values for these breeds (2.46 ± 0.16, on average). No differences were observed in the other milk components (P = 0.65 to 0.85). Despite that, the somatic cell count (SCC) values showed a statistical tendency in PM than in MP (1.89 vs. 2.13 ± 0.05; P = 0.07). In conclusion, low-fat contents were observed in both groups, possibly due to the low quality of foods used in ruminant feeding. While that, the parity and advanced lactation conditioned the SCC contents. Therefore, other studies should be performed to identify more factors that could be determinants. Keywords: Milk, Tropical livestock, Udder health

Somatic Cell Count Evaluation in Early Lactation between Primiparous and Multiparous Bos indicus Cows

Using Bos indicus cows, a study examined the relationship between somatic cell count (SCC) and milk yield. For this study, one hundred fifty cows (Primiparous, PM, 75 and Multiparous, MP 75) in early lactation (days in milk, PM =134 ± 3; MP = 136 ± 5), milk production (9,88 kg/d, on average) of the creole breed Gyr lechers were enrolled. Before being assigned to each treatment, the SCC values were lower than 220,000 cells/mL, on average. All cows were maintained to graze daily on Megathyrsus maximus and supplemented with Morus alba ad libitum, being hand-milking at 0700 daily. Before analysis, the SCC was logarithmically transformed (log10). Then, PROC Mixed from SAS version 9.4 was used to evaluate all measurements. Regarding our results, the MP had greater milk yields than PM cows (10.83 vs. 9.18 ± 0.38 kg/d; P = 0.003). Similar results were observed for fat-corrected milk (8.26 vs. 6.80 ± 0.34; P = 0.002), although the fat values did not differ between both groups (P = 0.86) being lower than referential values for these breeds (2.46 ± 0.16, on average). No differences were observed in the other milk components (P = 0.65 to 0.85). Despite that, the somatic cell count (SCC) values showed a statistical tendency in PM than in MP (1.89 vs. 2.13 ± 0.05; P = 0.07). In conclusion, low-fat contents were observed in both groups, possibly due to the low quality of foods used in ruminant feeding. While that, the parity and advanced lactation conditioned the SCC contents. Therefore, other studies should be performed to identify more factors that could be determinants. Keywords: Milk, Tropical livestock, Udder health

Full-fat corn germ improves the performance and milk fat yield of Girolando cows fed sugarcane bagasse and cactus cladodes as forage sources.

We investigated the effects of replacing ground corn with full-fat corn germ (FFCG) on milk production, milk composition, and nutrient use in cows fed sugarcane bagasse and cactus cladodes. Ten multiparous Girolando cows (average body weight 500 ± 66kg, 90 ± 15 days in milk) were distributed in a replicated 5 × 5 Latin Square and assigned to five dietary treatments containing 0%, 25%, 50%, 75%, or 100% of full-fat corn germ in substitution to ground corn. Full-fat corn germ increased fat-corrected milk yield by 2.2kg/day and the synthesis of fat, lactose, and total solids in milk by 94.4, 60.0, and 201.10g/day, respectively (p < 0.05). Cows fed corn germ quadratically increased (p < 0.05) dry matter intake by 1.01kg/day, with the intake of crude protein and total digestible nutrients following the same pattern. Conversely, the substitution of corn for full-fat corn germ linearly reduced (p < 0.05) the total non-fiber carbohydrate intake from 5.79 to 4.40kg/d. Except for ether extract and non-fiber carbohydrates, full-fat corn germ did not alter (p > 0.05) nutrient digestibility. Cows fed corn germ excreted less (p < 0.05) urea-N in milk and urine N. These results demonstrate that full-fat corn germ can partially replace ground corn to enhance the milk production efficiency of crossbred cows fed cactus cladodes and sugarcane bagasse. Furthermore, including sugarcane bagasse in FFCG-supplemented diets prevents milk fat depression in cows fed cactus cladodes.

Effects of feeding rumen-protected lysine during the postpartum period on performance and amino acid profile in dairy cows: A meta-analysis

Lysine is one of the limiting AA in the diets of dairy cows and is typically fed as rumen-protected Lys (RPL). We hypothesized that supplementation of RPL during the postpartum period would improve the productive performance in dairy cows. Objectives were to use meta-analytic methods to explore the effects of feeding RPL on performance and blood AA profile in lactating dairy cows. An additional objective was to identify an optimal concentration (%) of Lys in MP (LYSMP) and determine if responses to LYSMP were associated with the concentration (%) of Met in MP (METMP). The literature was systematically reviewed, and 13 experiments, comprising 40 treatment means and 594 lactating cows, were included in the meta-analysis. All experiments had a nonsupplemental control (CON; n = 17 treatment means), or a group supplemented with RPL (n = 23 treatment means). Cows supplemented with RPL were supplied additionally with a mean (±standard deviation) 19.3 ± 10.3 g/d metabolizable Lys (5.1-40.6 g/d). Meta-analytical statistics were used to estimate the weighted mean difference in STATA. Mixed models were fitted to the data to investigate the linear and quadratic effects of LYSMP, METMP, and interactions between LYSMP and METMP. All models included the random effect of experiment and weighting by the inverse of the SE of the means squared. Cows that began receiving RPL in early lactation (≤90 DIM) or for an extended duration (≥70 DIM) produced 1.51 kg/d more milk compared with CON cows. Increasing digestible LYSMP from 6.5% to 8.5% linearly increased yields of milk, FCM, ECM, and milk fat by 1.8, 2.5, 2.4, and 0.10 kg/d, respectively, and tended to increase milk protein yield and body weight gain by 0.07 and 0.09 kg/d, respectively, without a concurrent increase in DMI. Interactions between the linear effects of LYSMP and METMP were observed for FCM/DMI or ECM/DMI. In a diet with low METMP (e.g., 1.82% of MP), a digestible supply of 7.40% LYSMP would result in 1.46 and 1.47 kg/kg FCM/DMI or ECM/DMI, respectively; however, with high digestible METMP (e.g., 2.91% of MP), supplying 7.40% of digestible LYSMP would result in 1.68 and 1.62 kg/kg FCM/DMI or ECM/DMI, respectively. Increasing digestible LYSMP from 6.5% to 8.5% linearly increased blood concentrations of Lys by 16.6 µM, whereas blood concentrations of Met and Ala decreased by 4.6 and 6.0 µM, respectively. Nevertheless, an interaction was also observed between LYSMP and METMP for blood concentrations of total EAA because as METMP increased, the positive response to LYSMP on total EAA was also increased, suggesting a competitive mobilization of AA and their utilization in various body tissues. Only 4 out of the 13 experiments in this meta-analysis involved primiparous cows; thus, insufficient data were available to understand the role of supplemental RPL in primiparous cows. Collectively, feeding RPL improved productive performance, and the increments were maximized up to 9.25% of LYSMP in multiparous dairy cows.