Search

Background A more sustainable dairy cow diet was designed that minimizes use of feed components digestible by monogastric animals by increasing the quantity of forages. Objectives This study determined if feeding lactating cows the more sustainable, low-starch and high-fiber (LSHF) diet was associated with changes in raw milk microbiota composition and somatic cell count (SCC). Methods In a crossover design, 76 lactating Holstein cows were assigned to an LSHF diet or a high-starch and low-fiber (HSLF) diet, similar to common dairy cow diets in the United States, for 10 wk then placed on the opposite diet for 10 wk. The LSHF diet contained greater quantities of forages, beet pulp, and corn distillers' grain, but contained less canola meal and no high-moisture corn compared with the HSLF diet. Raw milk samples were collected from each cow 4–5 d before intervention and 5 wk into each diet treatment. Within 4 d, additional milk samples were collected for measurement of SCC using Fossmatic 7. The microbial community was determined by sequencing the 16S rRNA gene V4-V5 region and analyzing sequences with QIIME2. After quality filtering, 53 cows remained. Results Raw milk microbial communities differed by diet and time. Taxa associated with fiber consumption, such as Lachnospiraceae , Lactobacillus , Bacteroides , and Methanobrevibacter , were enriched with the LSHF diet. Meanwhile, taxa associated with mastitis, such as Pseudomonas , Stenotrophomonas , and Enterobacteriaceae , were enriched with the HSLF diet. Relatedly, an interaction of diet and time was found to impact SCC. Conclusions In raw milk, consumption of an LSHF diet compared with an HSLF diet was associated with changes in abundance of microbes previously associated with fiber consumption, udder health, and milk spoilage. Further research is needed to determine if an LSHF diet indeed leads to lower rates of mastitis and milk spoilage, which could benefit the dairy industry. [ABSTRACT FROM AUTHOR]

Macronutrient composition of human milk differs by infant sex, but few studies have examined sex differences in other milk components, or their potential modification by maternal body mass index (BMI). We compared milk intake and human milk hormone and cytokine concentrations at 1- and 3-month post-delivery and tested infant sex by maternal BMI (OW/OB vs. NW) interactions. Data were analysed for 346 mother–infant dyads in the Mothers and Infants Linked for Healthy Growth (MILk) Study at 1- and 3-month post-delivery. Infant milk intake was estimated by the change in infant weight after test feedings. Concentrations of glucose, insulin, leptin, adiponectin, interleukin-6 (IL-6), and C-reactive protein (CRP) were measured using ELISA. Multivariable linear regression and linear mixed models were used to estimate sex main effects and their interaction with maternal BMI. Mean glucose concentration at 1 month was 2.62 mg/dl higher for male infants, but no difference at 3 months was observed. Milk intake and concentrations for the other milk components were similar for males and females at both time points. Associations with infant sex did not differ significantly by maternal BMI. Among healthy United States mother–infant dyads, appetite, and growth-regulating factors in human milk did not differ significantly by infant sex. [ABSTRACT FROM AUTHOR]

Flunixin is a nonsteroidal anti-inflammatory drug and the most commonly prescribed analgesic in cattle in the United States. Recently, the US Food and Drug Administration (FDA) approved a transdermal formulation of flunixin for control of pyrexia associated with bovine respiratory disease and the control of pain associated with foot rot. The transdermal formulation is not currently approved for use in lactating dairy cattle in the United States, but extra-label use in dairy cattle is permissible under US regulations. The objectives of this study were to determine the pharmacokinetics in milk of dairy cows treated with transdermal flunixin and determine an appropriate withdrawal time for milk. Ten lactating Holstein cows were enrolled into the study in mid lactation. Following treatment, cows were milked 3 times per day through 144 h. Milk samples were collected for drug analysis using ultra-high-pressure liquid chromatography coupled with a triple quadrupole mass spectrometer. The geometric mean maximum concentration for flunixin in milk was 0.010 μg/mL and was 0.061 μg/mL for the active metabolite, 5-hydroxyflunixin. The geometric mean terminal half-life was 20.71 h for flunixin and 22.62 h for 5-hydroxyflunixin. Calculations to approximate a withdrawal time in milk following transdermal flunixin administration were accomplished using a statistical tolerance limit procedure. This analysis indicated that it would be prudent to observe a withdrawal period of 96 h following the last treatment. This is more than twice as long as the labeled withdrawal period of 36 h following use of the injectable formulation. The withdrawal period suggested by this work should be applied carefully, as this study was not conducted under the full quality control practices required by the US FDA for a full drug approval study. Caution should be taken when applying this withdrawal time to diseased animals, animals that are milked with different milking frequencies, and those in different stages of production as these have all been shown to affect drug depletion from milk. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Guided by the theory of reasoned action and social cognitive theory, this study was conducted to better understand how decisions to purchase organic or conventional milk are influenced by norms and attitudes established via human interactions and how those norms and attitudes vary by geographic region. An online Qualtrics survey was used to gain insight into behaviors, attitudes, and interactions of 308 milk consumers in various geographical regions of [State]. The findings indicate that urban, suburban, and rural consumers differ in some ways in their interactions related to milk information, as well as their perceptions of organic versus conventional milk. Based on the findings of the study, differences in personal networks and exposure to certain messaging in varying regions might perpetuate a more positive, confident, and informed view of organic or conventional milk products in some areas more so than others. The researchers recommend using the results of the study to tailor messages to the specific information needs of consumers in urban, suburban, and rural regions of [State]. [ABSTRACT FROM AUTHOR]

Heat stress at the time of conception affects the subsequent milk production of primiparous Holstein cows; however, it is unknown whether these effects are maintained across multiple lactations. Therefore, the objective of the current study was to examine the relationship between periconceptional heat stress and measurements of milk production and composition in cows retained within a herd for multiple lactations. National Dairy Herd Improvement Association data was obtained from Dairy Records Management Systems. Records included milk production data and milk composition data from over 75,000 and 44,000 Holstein cows, respectively, born between 2000 and 2010 in Florida, Georgia, and Texas. Conception dates were calculated by subtracting 276 d from the recorded birth date. Records for cows conceived within the months of June, July, and August were retained as heat stress conceived (HSC) cows; cows conceived within the months of December, January, and February were retained as thermoneutral conceived (TNC) contemporaries. Adjusted 305-d mature equivalent milk, protein percent and fat percent were evaluated with a mixed model ANOVA using SAS. Milk production was significantly affected by periconceptional heat stress. When a significant difference or tendency for a difference was detected between the HSC and TNC cows, the TNC produced more milk in all but one comparison. The advantage in milk production for the TNC cows over the HSC cows ranged from 82 ± 42 to 399 ± 61 kg per lactation. Alterations in fat and protein percentage were variable and most often detected in first lactations (first > second or third). Overall, the most striking result of this study is the consistency of the relationship between HSC and milk production. The nature of this relationship suggests that heat stress at or around the time of conception impairs cow milk yield throughout her lifetime. [ABSTRACT FROM AUTHOR]

Consumers are increasingly aware that food components have the potential to influence human health maintenance and disease prevention, and dietary fatty acids (FA) have been of special interest. It has been 25 years since the last survey of US milk FA composition, and during this interval substantial changes in dairy rations have occurred, including increased use of total mixed rations and byproduct feeds as well as the routine use of lipid and FA supplements. Furthermore, analytical procedures have improved allowing greater detail in the routine analysis of FA, especially trans FA. Our objective was to survey US milk fat and determine its FA composition. We obtained samples of fluid milk from 56 milk processing plants across the US every 3 mo for one year to capture seasonal and geographical variations. Processing plants were selected based on the criteria that they represented 50% or more of the fluid milk produced in that area. An overall summary of the milk fat analysis indicated that saturated fatty acids comprised 63.7% of total milk FA with palmitic and stearic acids representing the majority (44.1 and 18.3% of total saturated fatty acids, respectively). Unsaturated fatty acids were 33.2% of total milk FA with oleic acid predominating (71.0% of total unsaturated fatty acids). These values are comparable to those of the previous survey in 1984, considering differences in analytical techniques. Trans FA represented 3.2% of total FA, with vaccenic acid being the major trans isomer (46.5% of total trans FA). Cis-9, trans-11 18:2 conjugated linoleic acid represented 0.55% total milk FA, and the major n-3 FA (linolenic acid, 18:3) composed 0.38%. Analyses for seasonal and regional effects indicated statistical differences for some FA, but these were minor from an overall human nutrition perspective as the FA profile for all samples were numerically similar. Overall, the present study provides a valuable database for current FA composition of US fluid milk, and results demonstrate that the milk fatty acid profile is remarkably consistent across geographic regions and seasons from the perspective of human dietary intake of milk fat. [ABSTRACT FROM AUTHOR]

Abstract: This study determined the sensory characteristics of ultrapasteurized (UP) lactose-free milk of different fat contents, and compared them with regular milk. Nine milk samples (six UP lactose-free and three regular) containing 0, 2 or 3g milkfat/100mL were tested by a descriptive panel. A consumer test with three UP lactose-free milk and three regular samples was also conducted. The skim milks were found to be lacking in freshness and the dairy notes were lower compared to the higher-fat-content milks. The UP lactose-free milks were different from the regular milk because of higher intensities of cooked, processed, and sweet attributes. UP lactose-free milks tended to score higher than the regular milks at the same fat content for dairy-related attributes, but this difference was not significant for the reduced-fat milks. Although majority of the consumers in the present study were aware that UP lactose-free milks existed in the market, only few had tasted them before. The higher intensities of cooked and sweet flavor attributes in the UP lactose-free milks might be a hindrance to their consumption by the lactose-intolerant population. More efforts are needed from the dairy industry to develop better lactose-free products and to educate consumers about lactose-free dairy products. [Copyright &y& Elsevier]

Widespread genotyping of US dairy goat breeds for casein variants has not been reported, even though the genetic data could be of use in selective breeding programs. For instance, variability in the content of protein and solids in goat milk is attributed to allelic differences in the goat αs1-casein gene. Concentrations of αs1-casein in goat milk are positively correlated with milk components and coagulation properties. The alleles A and B are designated as strong alleles, resulting in the greatest amount of αs1-casein in goat milk, whereas the E allele produces intermediate amounts and the weak allele F produces the least concentrations of αs1-casein in goat milk. Here we report on one of the first surveys of the distribution of αs1-casein genotypes in US dairy goats. The population surveyed, consisting of a total of 257 American dairy goats representing 7 main dairy breeds, contained a greater predominance of the weaker alleles, E and F, than the strong alleles, A and B. Allele distribution was related to breed, with Toggenburg, Alpine, Saanen, and Oberhasli containing the most E and F alleles and LaMancha, Nubian, and Nigerian Dwarf the fewest. Quantification of αs1-casein production by 2-dimensional gel electrophoresis demonstrated that F/F animals had the least amount of αs1-casein protein in their milk compared with all other genotypes. The results indicate that genetic improvement of dairy goats in the United States could be achieved if an αs1-casein breeding scheme were adopted. [ABSTRACT FROM AUTHOR]

Simple Summary: The evaluation and implementation of an automated body condition scoring technology for dairy cattle. Body condition scoring in cattle is an effective tool to assess body reserves of individual animals. On-farm body condition scoring requires training and time to appropriately evaluate the animals. The aim of this study was to evaluate the implementation of an automated body condition scoring technology compared to conventional manual scoring. We found that the automated body condition scoring technology was highly correlated with manual scoring. The system was accurate for a body condition scoring (BCS) between 3.0 and 3.75, with a lower error rate compared to the standard detection threshold of 0.25 for manual scoring. However, the system was found to be in a different range of scores and was inaccurate at determining under- and over-conditioned cattle compared to manual scoring. Body condition scoring (BCS) is the management practice of assessing body reserves of individual animals by visual or tactile estimation of subcutaneous fat and muscle. Both high and low BCS can negatively impact milk production, disease, and reproduction. Visual or tactile estimation of subcutaneous fat reserves in dairy cattle relies on their body shape or thickness of fat layers and muscle on key areas of the body. Although manual BCS has proven beneficial, consistent qualitative scoring can be difficult to implement. The desirable BCS range for dairy cows varies within lactation and should be monitored at multiple time points throughout lactation for the most impact, a practice that can be hard to implement. However, a commercial automatic BCS camera is currently available for dairy cattle (DeLaval Body Condition Scoring, BCS DeLaval International AB, Tumba, Sweden). The objective of this study was to validate the implementation of an automated BCS system in a commercial setting and compare agreement of the automated body condition scores with conventional manual scoring. The study was conducted on a commercial farm in Indiana, USA, in April 2017. Three trained staff members scored 343 cows manually using a 1 to 5 BCS scale, with 0.25 increments. Pearson's correlations (0.85, scorer 1 vs. 2; 0.87, scorer 2 vs. 3; and 0.86, scorer 1 vs. 3) and Cohen's Kappa coefficients (0.62, scorer 1 vs. 2; 0.66, scorer 2 vs. 3; and 0.66, scorer 1 vs. 3) were calculated to assess interobserver reliability, with the correlations being 0.85, 0.87, and 0.86. The automated camera BCS scores were compared with the averaged manual scores. The mean BCS were 3.39 ± 0.32 and 3.27 ± 0.27 (mean ± SD) for manual and automatic camera scores, respectively. We found that the automated body condition scoring technology was strongly correlated with the manual scores, with a correlation of 0.78. The automated BCS camera system accuracy was equivalent to manual scoring, with a mean error of −0.1 BCS and within the acceptable manual error threshold of 0.25 BCS between BCS (3.00 to 3.75) but was less accurate for cows with high (>3.75) or low (<3.00) BCS scores compared to manual scorers. A Bland–Altman plot was constructed which demonstrated a bias in the high and low automated BCS scoring. The initial findings show that the BCS camera system provides accurate BCS between 3.00 to 3.75 but tends to be inaccurate at determining the magnitude of low and high BCS scores. However, the results are promising, as an automated system may encourage more producers to adopt BCS into their practices to detect early signs of BCS change for individual cattle. Future algorithm and software development is likely to increase the accuracy in automated BCS scoring. [ABSTRACT FROM AUTHOR]

The article discusses that the Food and Drug Administration (FDA) reviews possible improvements in its routine tests for drug residues in milk. Clinical professor Paul Rapnicki believes that the move is due to the tissue residues found in cull dairy cattle and expanding the test could determine whether the misuse of FDA-approved drugs may cause undetected milk residues. It cites that milk producers who will be found positive for antimicrobial residues may face financial and punitive actions.

Deals with the issues concerning imitated and substitute infant milk in the United States (U.S.). Definition of the United States Food and Drug Administration of substitute milk; Contention on the nutritional content of substitute and imitation milk.