Nutrition and Osteoporosis Prevention.

PURPOSE OF REVIEW: Osteoporosis affects 50% of women and 20% of men after the age of 50. Fractures are associated with significant morbidity, increased mortality and altered quality of life. Lifestyle measures for fragility fracture prevention include good nutrition including adequate protein and calcium intakes, vitamin D sufficiency, and regular weight bearing physical exercise. RECENT FINDINGS: Dietary protein is one of the most important nutritional considerations as it affects bone mineral density, trabecular and cortical microstructure, and bone strength. When calcium intake is sufficient, higher dietary protein intake is associated with lower risk of fracture. Dairy products are a valuable source of calcium and high quality protein. Dairy product consumption, particularly fermented dairy products, are associated with a lower risk of hip fracture and vegan diets are associated with increased fracture risk. Other dietary factors associated with reduced fracture risk include at least 5 servings per day of fruits and vegetables, regular tea drinking, adherence to a Mediterranean diet and other dietary patterns which provide fibers, polyphenols and fermented dairy products. Such dietary patterns may confer health benefits through their effect on gut microbiota composition and/or function. A balanced diet including minerals, protein, fruits and vegetables is an important element in the prevention of osteoporosis and of fragility fracture.

Methane Emissions from Dairy Operations in California's San Joaquin Valley Evaluated Using Airborne Flux Measurements.

State inventories indicate that dairy operations account for nearly half of California's methane budget. Recent analyses suggest, however, that these emissions may be underestimated, complicating efforts to develop emission reduction strategies. Here, we report estimates of dairy methane emissions in the southern San Joaquin Valley (SJV) of California in June 2021 using airborne flux measurements. We find average dairy methane fluxes of 512 ± 178 mg m-2 h-1 from a region of 300+ dairies near Visalia, CA using a combination of eddy covariance and mass balance-based techniques, corresponding to 118 ± 41 kg dairy-1 h-1. These values estimated during our June campaign are 39 ± 48% larger than annual average estimates from the recently developed VISTA-CA inventory. We observed notable increases in emissions with temperature. Our estimates align well with inventory predictions when parametrizations for the temperature dependence of emissions are applied. Our measurements further demonstrate that the VISTA-CA emission inventory is considerably more accurate than the EPA GHG-I inventory in this region. Source apportionment analyses confirm that dairy operations produce the majority of methane emissions in the southern SJV (∼65%). Fugitive oil and gas (O&G) sources account for the remaining ∼35%. Our results support the accuracy of the process-based models used to develop dairy emission inventories and highlight the need for additional investigation of the meteorological dependence of these emissions.

First test-day postcalving risk factors for clinical mastitis in southern Chile dairy farms: A retrospective cohort study.

We conducted a retrospective cohort study to evaluate risk factors associated with clinical mastitis in dairy cows in southern Chile between the first milk test after calving to 200 d in milk (DIM). Data from 8,772 cows were collected from June 2017 to November 2019 on 10 dairy farms selected by convenience in southern Chile. Data were analyzed using a multivariable mixed logistic regression using a manual backward selection process with logit link function and farm as a random effect. The dependent variable was clinical mastitis between the first milking sample collected by monthly milk sampling program up to 200 DIM. Days in milk, fat, urea, parity, season, and somatic cell counts were statistically associated with clinical mastitis in the first 200 d in milk. Cows with higher than average milk yield, parity, urea, and somatic cell count were at greater odds of being diagnosed with clinical mastitis compared with their respective referents. In contrast, higher milk fat was associated with lower odds of clinical mastitis. Significant interactions between days in milk with season and parity were observed, where for every 5-d increase in DIM, the odds of clinical mastitis decreased by different proportions depending on the interaction. Identified risk factors for clinical mastitis using first monthly milk sampling data can help dairy farmers in Chile implement herd-level mastitis prevention and control measures.

Characterization and Authentication of "Ricotta" Whey Cheeses through GC-FID Analysis of Fatty Acid Profile and Chemometrics.

The fatty acid (FA) profiles of 240 samples of ricotta whey cheese made from sheep, goat, cow, or water buffalo milk were analyzed by gas-chromatography (GC). Then, sequential preprocessing through orthogonalization (SPORT) was used in order to classify samples according to the nature of the milk they were made from. This strategy achieved excellent results, correctly classifying 77 (out of 80) validation samples. Eventually, since 36 (over 114) sheep ricotta whey cheeses were PDO products, a second classification problem, finalizing the discrimination of PDO and Non-PDO dairies, was faced. In this case, two classifiers were used, SPORT and soft independent modelling by class analogy (SIMCA). Both approaches provided more than satisfying results; in fact, SPORT properly assigned 63 (of 65) test samples, whereas the SIMCA model accepted 14 PDO individuals over 15 (93.3% sensitivity) and correctly rejected all the other samples (100.0% specificity). In conclusion, all the tested approaches resulted as suitable for the two fixed purposes. Eventually, variable importance in projection (VIP) analysis was used to understand which FAs characterize the different categories of ricotta. Among the 22 analyzed compounds, about 10 are considered the most relevant for the solution of the investigated problems.

Effect of an ICU diary on psychiatric disorders, quality of life, and sleep quality among adult cardiac surgical ICU survivors: a randomized controlled trial.

BACKGROUND: Although studies on the effectiveness of the use of ICU diaries on psychiatric disorders and quality of life have been published, the results still seem to be controversial. The study aimed to determine the effects of using an ICU diary on psychiatric disorders, sleep quality, and quality of life (QoL) in adult ICU survivors in China. METHODS: One hundred and twenty-six patients who underwent a scheduled cardiac surgery and were expected to stay ≥ 24 h in ICU were randomized to two groups (63 in each group). The patients in the intervention group received the use of ICU diaries during the period of post-ICU follow-up, while the patients in the control group received usual care without ICU diaries. The primary outcome was significant PTSD symptoms (Chinese version of Impact of Event Scale-Revised, IES-R; total score ≥ 35 was defined as significant PTSD symptoms) and its severity in patients 3 months post-ICU. The secondary outcomes included memories of the ICU at 1 month, QoL (Medical Outcomes Study 36-item Short-Form, SF-36), sleep quality (Pittsburgh Sleep Quality Index Questionnaire, PSQI), anxiety, and depression symptoms (Hospital Anxiety and Depression Scale, HADS) at 3 months. RESULTS: Eighty-five and 83 patients completed the follow-up interviews at 1 month and 3 months post-ICU, respectively. Significant PTSD symptoms were reported by 6 of 41 (14.63%) in the intervention group vs 9 of 42 (21.43%) in the control group (risk difference, - 9% [95% CI, - 2% to 21%], P = 0.10). There was no significant differences between groups in IES-R score, symptoms of intrusion, symptoms of avoidance, numbers of memories of feeling and delusional memories, SF-36 score and anxiety score (P > 0.05), while significant differences were found in symptom of hyperarousal score, numbers of factual memories and PSQI score (P < 0.05). No adverse effect was reported. CONCLUSIONS: Using an ICU diary is not useful for preventing PTSD symptoms and anxiety symptoms and preserving the quality of life of the patients at 3 months post-ICU, while it significantly improves the survivor's factual memory of ICU and sleep quality, and prevents the hyperarousal symptom. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR-IOR-16009109, registered on 28 August 2016.

Analysis of closed versus operating dairies in the southeastern United States.

This study analyzed differences between dairies that have closed compared with dairies still operating in the southeastern United States. Significant changes have occurred in the US dairy industry in the last decade, involving the number of dairy farms, herd size, milk quality, and management practices, yet the dairy industry remains the fourth leading agricultural sector in the United States, with $38 billion of milk sales in 2017. Although the number of dairy cows in the United States has remained relatively constant over the past decade, at approximately 9 million head, the number of dairy operations has decreased by 30%, resulting in larger dairies. This trend is even more prevalent in the southeastern United States, where the number of dairies has decreased by 39% from 5,315 in 2008 to only 3,235 in 2017. Additionally, downward pressure on bulk tank somatic cell count, which is used as a milk quality metric and has implications regarding animal health, intensified with US processors' introduction of incentive and penalty systems for quality milk production, necessitating better management of mastitis in dairy herds. In this context, this study examines factors that affect southeastern US dairy farms' persistence in the industry by using primary survey data collected in 2013 through a mail survey of Grade A dairies in Georgia, Mississippi, Kentucky, North Carolina, South Carolina, Tennessee, and Virginia. Dairies that were no longer operational had exited the industry from 2007 through 2014. A probit regression was used to determine which farm and operator characteristics were associated with the dairy's operational status. Dairy farms with more cows and higher average milk production per cow were more likely to be operational. For an additional 10 kg/d of milk production per cow, the dairy was 1.5% more likely to be operational. For each 100 additional cows a dairy had, it was 4% more likely to be operational. The analysis also identifies nonpecuniary determinants of operational status for southeastern US dairies, such as mastitis management practices. Findings suggest that operations capable of leveraging scale effects are more likely to remain operational, with results affirming the consolidation of the US dairy industry and demonstrating that more productive farms are more likely to stay in operation. Results also suggest that factors other than farm size affect a dairy's operational status.

Measuring and comparing the water activity and salt content in Parenica cheeses made by traditional and industrial technology.

BACKGROUND: Slovenská Parenica is one of the most traditional and ever-popular sheep´s milk cheese specialities. This cheese has been registered as a geographical indication (PGI) in the EU. Parenica cheese is produced also from cow´s milk, but without the trade name "Slovenská/Slovak". OBJECTIVE: The aim of our research was was statistical reporting and results visualization of water activity analysis and salt content in cow´s milk Parenica cheeses from 8 small and medium-sized Slovak dairy producers. MATERIAL AND METHOD: A total of 320 samples of smoked and non-smoked Parenica cheeses made from cow´s milk using traditional and industrial technology were examined during the 10-month period. Each cheese was analysed immediately after sampling (A) and subsequently after 7 days of storing at 4°C (B). The salt content was measured on the Chloride analyser M 926 and the water activity on the Fast-Lab meter. Due to the hierarchical design of the experiment, the linear mixed models via the R statistical environment to compare the differences in the water activity and salt content were used. RESULTS: Statistical reporting and visualization of water activity measurements showed significant differences between samples A and B ( p = 0.0129) and between kinds of Parenica cheese ( p = 0.0196). The value of water activity ranged from 0.908 to 0.975 (A) with the increasing trend after storing in both kinds of Parenica cheese. The impact of dairy producer type was not significant. The higher content of NaCl was found in fresh Parenica cheese from small farms (nonsmoked: 2.51 ±1.12 g/100 g, smoked: 1.97 ±0.89 g/100 g). The average salt content in cheeses from industrial dairies was 1.65 ±0.34 g/100 g (non-smoked) and 1.96 ±0.43 g/100 g (smoked). Results showed lower variability of salt content in cheeses from industrial dairies. CONCLUSIONS: It can be concluded that especially the small producers can have probably problem in noncompliance with the technological processes, non-implementation of standardized procedures and underestimation of hygiene regulations.

Association of consumption of dairy products and meat with retinal vessel calibers in subjects at increased cardiovascular risk.

BACKGROUND AND AIMS: Association of dairy products and meat consumption with macrocirculation is previously described, but such association with microcirculation is poorly investigated. We aimed to test the hypothesis that the consumption of high- and low-fat dairy products as well as red, white, and processed meat is associated with retinal vessel calibers in adults at an increased risk of cardiovascular disease (CVD). METHODS AND RESULTS: In consecutive subjects (n = 181, age: 51.3 ± 12.4 years, 51.4% women) without CVD and diabetes mellitus but with increased CVD risk, we obtained digital left and right retinal images. These images were assessed with validated software to determine central retinal arteriolar and venular equivalents and the arteriolar to venular ratio (CRAE, CRVE, and AVR, respectively). The consumption of dairy products and meat was assessed through 24-h recalls in all volunteers. After adjustment for potential confounders, the following findings were obtained: (i) low-fat milk and yogurt were positively associated with CRAE (b=0.145, p=0.031 left; b=0.141, p=0.038 right) and inversely associated with CRVE (b=-0.155, p=0.026 left; b=-0.146, p=0.041 right); (ii) low-fat cheese was positively associated with CRAE (b=0.164, p=0.011 left and b=0.155, p=0.017 right); and (iii) red meat was inversely associated with CRAE (b=-0.143, p=0.032 left; b=-0.114, p=0.050 right). High-fat milk, yogurt, and cheese or white and processed meat were not found to be associated with retinal vessel calibers. CONCLUSIONS: High consumption of low-fat milk, yogurt, and cheese and low consumption of red meat could be beneficial for retinal microvascular health. Prospective studies are needed to verify these findings.

Survey of management practices related to bovine respiratory disease in preweaned calves on California dairies.

In the spring of 2013, a survey of California (CA) dairies was performed to characterize management practices related to bovine respiratory disease in preweaned calves, compare these practices across geographic regions of the state, and determine the principal components that explain the variability in management between herds. The questionnaire consisted of 53 questions divided into 6 sections to assess management practices affecting dairy calves from precalving to weaning. The questionnaire was mailed to 1,523 grade A licensed dairies in CA and 224 responses (14.7%) were collected. Survey response rates were similar over the 3 defined regions of CA: northern CA, northern San Joaquin Valley, and the greater southern CA region. The mean size of respondent herds was 1,423 milking cows. Most dairies reported raising preweaned calves on-site (59.7%). In 93.3% of dairies, preweaned calves were raised in some form of individual housing. Nonsaleable milk was the most frequent liquid diet fed to preweaned heifers (75.2%). Several important differences were identified between calf-raising practices in CA and practices reported in recent nationwide studies, including herd sizes, housing practices, and sources of milk fed to heifers. The differences between the CA and nationwide studies may be explained by differences in herd size. Regional differences within CA were also identified. Compared with the 2 other regions, northern CA dairies were found to have smaller herds, less Holstein cattle, calves remained with dams for longer periods of time after calving, were more likely to be certified organic dairies, and raised their own calves more often. Principal component analysis was performed and identified 11 components composed of 28 variables (questions) that explained 66.5% of the variability in the data. The identified components and questions will contribute to developing a risk assessment tool for bovine respiratory disease in preweaned dairy calves.

Segmentation of Parmigiano Reggiano dairies according to cheese-making technology and relationships with the aspect of the cheese curd surface at the moment of its extraction from the cheese vat.

Parmigiano Reggiano cheese dairies develop specific cheese-making strategies to adapt the variable characteristics of raw, not standardized milk to the final goal of obtaining cheese consistent with the standard. Analyzing 1,175 cheese-making reports from 30 out of 383 dairies associated with the Parmigiano Reggiano Consortium in 2010 and 2011, 4 groups of Parmigiano Reggiano dairies using specific cheese-making technologies were discriminated by means of multiple linear discriminant analysis. Cheese makers manage cheese-making practices to obtain curd with different roughness properties, classified according to jargon words such as "rigata" and "giusta" or synonyms, because they believe that the roughness of the cheese curd surface immediately after the extraction from the vat is associated with different whey-draining properties and to the final outcome of the cheese. The aspect of the surfaces of the curds produced by the 4 groups of dairies was different according to the technology applied by each group. Cutting of the coagulum when it is still soft for a longer time and faster cooking of the cheese curd grains were associated with a less rough appearance of the surface of the curd, whereas under the opposite conditions, cutting the coagulum when it is firm for a shorter time, led to a curd with a rougher surface. These findings partially support the traditional feeling of Parmigiano Reggiano cheese makers, who consider the curd surface aspect one of the main drivers for their technological choices; to date, however, no data are provided about correlation between the aspect of the curd and the quality of the ripened cheese. If a sufficiently strong correlation could be demonstrated by the future development of the research, the operational effectiveness of Parmigiano Reggiano dairies will be able to largely benefit from the availability of sound and early process markers.

Brazilian artisanal Colonial cheese: characterization, microbiological safety, and survival of Salmonella enterica serovar Enteritidis during ripening.

The artisanal Colonial cheese is typical of the southern region of Brazil and dates back to the colonization by Italian and German immigrants. Produced with raw milk, it is the main cheese produced by more than 15,200 small rural proprieties. The consumer increasingly appraises food with territorial valorization, demanding specific sanitary norms for this type of cheese. This work aimed to know the physical-chemical characteristics of the cheeses produced in the west of Santa Catarina State, to study the ripening time to reach microbiological safety, and to experimentally observe the survival of Salmonella enterica serovar Enteritidis ATCC 13076 during the ripening. The physical-chemical characterization was performed with 129 samples of cheeses. Five dairies were selected for evaluation of the ripening process. Salmonella survival using a challenge test was performed on three batches prepared in a pilot plant. The cheeses were classified as high (15.4%), medium (74.6%), and low moisture (9.2%), and concerning fat content as semi-fat (37.5%) and fat (62.5%). Salmonella challenge test demonstrated their survival for up to 28 days, depending on the initial contamination. The ripening monitoring showed that thermotolerant coliforms could be a good indicator of the process because they are the most persistent microorganisms.

Management Practices of Bovine Mastitis and Milk Quality on Egyptian Dairies.

Milk production continues to be the main source of income for dairy producers, and mastitis continues to be the major health challenge for dairy cows worldwide. The objective of the current study was to describe the different management practices implemented in Egyptian dairies, which may influence mastitis and improve milk quality. An in-person survey was completed with herd managers and owners of 20 Egyptian dairies selected using a stratified random sample from four of Egypt's milk sheds. The questionnaire included 80 questions that inquired about herd demographics, mastitis status and control, milking practices, and management practices of the study dairies. Statistical analyses included descriptive statistics, multiple factor analysis (MFA), and hierarchical clustering to identify the important principal components and different dairy clusters. Of the surveyed herds, 69.50% had less than 500 lactating cows, with Holstein as the main cow breed. The reported average milk production on the study herds was 31.1 (SE ± 1.10) Kg/cow/day. Housing of lactating, dry, and close-up cows was in open lots. The majority of the dairies milked cows were three times per day (90.63%), the remaining milked cows four (5.00%) or a mix of four and three times per day. Furthermore, herringbone parlor design was the most common parlor design (66.79%) in the study dairies. The most common disinfectants used for both pre- and post-milking teat dip were iodine-based, 90.0% and 95.0%, respectively, while 52.16% of the dairies reported that their milkers wore gloves during milking. The reported mean annual percentage of mastitis was 52.3%, as a percent of the milking herd. The study dairies reported the inspection of udder health through either visual inspection (95.00%), udder hygiene score (86.88%), teat end score (71.88%), and/or using CMT (54.91%). Contagious mastitis pathogens were reported in 45.2% of the study herds. More than 50% of the study herds relied on importing pregnant cows or pregnant heifers as replacements. Multiple factor analysis identified 20 questions and represented 5 components of variability related to mastitis on dairies. The current survey of Egyptian dairies described the herd demographics and different management practices related to mastitis control and prevention. All the study dairies relied on the blanket intramammary antimicrobial drugs at dry off when current research elsewhere has identified selective dry cow therapy as an integral component of antimicrobial stewardship on dairies. Further research is required to identify the association between different management factors and the occurrence of mastitis.

Birth of dairy 4.0: Opportunities and challenges in adoption of fourth industrial revolution technologies in the production of milk and its derivatives.

Embracing innovation and emerging technologies is becoming increasingly important to address the current global challenges facing many food industry sectors, including the dairy industry. Growing literature shows that the adoption of technologies of the fourth industrial revolution (named Industry 4.0) has promising potential to bring about breakthroughs and new insights and unlock advancement opportunities in many areas of the food manufacturing sector. This article discusses the current knowledge and recent trends and progress on the application of Industry 4.0 innovations in the dairy industry. First, the "Dairy 4.0" concept, inspired by Industry 4.0, is introduced and its enabling technologies are determined. Second, relevant examples of the use of Dairy 4.0 technologies in milk and its derived products are presented. Finally, conclusions and future perspectives are given. The results revealed that robotics, 3D printing, Artificial Intelligence, the Internet of Things, Big Data, and blockchain are the main enabling technologies of Dairy 4.0. These advanced technologies are being progressively adopted in the dairy sector, from farm to table, making significant and profound changes in the production of milk, cheese, and other dairy products. It is expected that, in the near future, new digital innovations will emerge, and greater implementations of Dairy 4.0 technologies is likely to be achieved, leading to more automation and optimization of this dynamic food sector.

Development, validation and application of multi-class methods for the analysis of food additives by liquid chromatography coupled to tandem mass spectrometry.

Food additives are used in numerous food products and are characterised by various physicochemical properties. In European member states, their use in food is regulated by the European Union. This work aimed to develop an accurate and high-throughput analytical method enabling the simultaneous determination of additives from different functional classes to facilitate controls and generate occurrence data for exposure assessments. The QuEChERS principle was applied due to its ease of implementation and flexibility to adjust to various food matrices. However, very polar substances could not be extracted with sufficient recoveries. Consequently, an alternative basic methanol sample-preparation methodology was developed. After sample preparation, the obtained extracts were analysed using ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Overall, the developed methodology allowed the quantification of 27 additives from the functional classes of colours, sweeteners, preservatives, and antioxidants in various foods (e.g. beverages, dairies, processed meals). The methods were also validated in terms of selectivity, linearity, matrix effect, limit of quantification, accuracy, repeatability, and intra-laboratory reproducibility. Finally, the methods were successfully applied to eighty-four actual samples. All additives were found below authorised levels. However, irregularities were spotted in labelling.

Italian Tracing System for Water Buffalo Milk and Processed Milk Products.

This document describes the development of a tracing system for the buffalo supply chain, namely an online computer system in which farmers, dairies, and brokers must maintain records of the production of milk through to the production of derivatives. The system is jointly used throughout the Italian national territory by the Istituto Zooprofilattico Sperimentale del Mezzogiorno (IZSM) and the Sistema Informativo Agricolo Nazionale Italiano (SIAN), after being made mandatory and regulated with the publication of the Ministerial Decree of 9 September 2014. Farmers are obligated to communicate their daily production of bulk milk, the number of animals milked, the number of the delivery note of the sale, and the name of the purchaser; within the first week of the month, they must communicate the milk production of each animal milked. Dairies are required to communicate the milk and the processed product (mozzarella, yogurt, etc.) purchased on a daily basis. The intermediaries are required to communicate the daily milk purchased, both fresh and frozen, the semi-finished product, and the sale of the same. The tracing system linked to the project authorized by the Ministry of Health, called "Development, validation and verification of the applicability of an IT system to be used for the management of traceability in the buffalo industry", provides operators with the monitoring of production and sales in real time through alerts and access logs. Currently, there are 1531 registered farmers, 601 non-PDO dairies, 102 PDO dairies, 68 non-PDO intermediaries, and 17 PDO intermediaries in Italy. The system provides support for the recovery of the buffalo sector; from the analysis of the data extrapolated from the tracing system of the buffalo supply chain for the years 2016 to 2019, this paper highlights that the application of the Ministerial Decree No. 9406 of 9 September 2014 and the tracing of the supply chain have increased the price of buffalo milk at barns from EUR 1.37/kg to EUR 1.55/kg from 2016 to 2019.

Robot milking and relationship with culling rate in dairy cows.

Cow routines and behavioral responses are altered substantially following the installation of robot milking. The present study was designed to analyze the effect that switching from milking parlor to automatic milking system (AMS) had on the culling rate (due to various causes) of dairy cattle. For this purpose, culling records and causes for culling were tracked in 23 dairy farms in the Galicia region (NW Spain). The animals in these farms were monitored for 5 years. For the present study, that length of time was divided into three different stages, as follows: 2 years before switching from a milking parlor to AMS (stage 1), the 1st year following the implementation of AMS (stage 2) and the 2nd and 3rd years succeeding the implementation of AMS (stage 3). Cox models for survival analysis were used to estimate the time to culling due to different reasons during stage 1 in relation to stages 2 and 3. The data indicated that the risk of loss due to death or emergency slaughter decreased significantly following the installation of AMS. In contrast, the risk of culling due to low production, udder problems, infertility or lameness increased significantly. Low-production cows (such as cows in advanced lactation due to infertility) or sick cows (such as mastitic or lame cows) allegedly have a noticeable effect both on the performance and the amortization of the cost of AMS, which in turn would lead to a higher probability of elimination than in conventional systems.

Fecal Microbial Communities in a Large Representative Cohort of California Dairy Cows.

Improved sequencing and analytical techniques allow for better resolution of microbial communities; however, the agriculture field lacks an updated analysis surveying the fecal microbial populations of dairy cattle in California. This study is a large-scale survey to determine the composition of the bacterial community present in the feces of lactating dairy cattle on commercial dairy operations. For the study, 10 dairy farms across northern and central California representing a variety of feeding and management systems were enrolled. The farms represented three typical housing types including five freestall, two drylot and three pasture-based management systems. Fresh feces were collected from 15 randomly selected cows on each farm and analyzed using 16S rRNA gene amplicon sequencing. This study found that housing type, individual farm, and dietary components significantly affected the alpha diversity of the fecal microbiota. While only one Operational Taxonomic Unit (OTU) was common among all the sampled individuals, 15 bacterial families and 27 genera were shared among 95% of samples. The ratio of the families Coriobacteriaceae to Bifidobacteriaceae was significantly different between housing types and farms with pasture fed animals having a higher relative abundance of Coriobacteriaceae. A majority of samples were positive for at least one OTU assigned to Enterobacteriaceae and 31% of samples contained OTUs assigned to Campylobacter. However, the relative abundance of both taxa was <0.1%. The microbial composition displays individual farm specific signatures, but housing type plays a role. These data provide insights into the composition of the core fecal microbiota of commercial dairy cows in California and will further generate hypotheses for strategies to manipulate the microbiome of cattle.

Productividad y eficiencia de ganaderías lecheras especializadas en el Valle del Cauca (Colombia) / Productivity and efficiency of specialized dairy farms in the Valley of Cauca (Colombia)

RESUMEN El estudio caracterizó la productividad y eficiencia de 52 lecherías especializadas en el Valle del Cauca (Colombia). Se encontró que en promedio los predios fueron de 41,3 hectáreas y 133 animales, respectivamente. El cuadro reproductivo supuso: días abiertos (97-225), servicios por concepción (1,4-5,4) e intervalo entre partos en días (IPP) (382-520). Las pasturas básicas fueron estrella C.plestostachyusy guinea P. maximun, con rendimientos anuales de 18,6 Ton MS.ha-1, un consumo de MS de pasto por vaca de 9,44 kg y un total de 12,2 kg incluyendo los concentrados. Se determinó una relación lineal Y=Producción de leche (kg.día) = 5,6639 + 0,5513 X, R2=0,77, donde solo con pastoreo las vacas producen 5,66 l.vaca-1día y cada kg de concentrado adicional incrementó en 0. 5513 l.vaca-1día. Las vacas productivas fueron 84,8 vacas.hato-1 con 11,9 l.vaca-1día. La carga animal por finca fue 3,2 UGG.ha-1 con una productividad de 7965 litros.ha-1 año; donde por cada UGG que ingresa al sistema se mejora en 2816 l.ha-1año. De 34 variables analizadas las que determinaron la productividad de las fincas fueron: litros totales por lactancia (33,3%), vacas en ordeño (17,7%), hectáreas productivas (11,0%), 1. ha-1 año (7,8%), kilogramos de concentrado (5,3%) y MS del pasto en kg.ha-1(4,5%). Se identificaron cuatro sistemas de producción con base en pastoreo que dependen críticamente de los suplementos concentrados con asimetrías en componentes raciales que afectan negativamente la productividad.

ABSTRACT The study characterizes productivity and efficiency of 52 specialized dairies in Valle del Cauca (Colombia). It was found that, on average, the farms were 41.3 hectares and 133 animals respectively. The reproductive status was: open days (97-225), services by conception (1.4- 5.4), in interval between births in days (IPP) (382-520). The basic pastures were Stargrass C. plestostachyus and Guinea P. maximun, with yields per year of 18.6 DM.Ton.ha-1 year and dry matter intake (DMI) of cow pasture of 9.44 kg and total of 12.2 kg including supplements. A linear relationship was determined: Y = Milk yield (kg.day) = 5.6639 + 0.5513 X, R2 = 0.77, where with only grazing, cows produce 5.66 l.cow-1day and each kg of additional supplements increases by 0.5513 l.cow-1 day. The productive cows were 84.8 farm-1 cows with 11.9 l.cow-1day. The animal load per farm was 3.2 large livestock units (LLU)) per ha with a productivity of 7965 liters.ha-1year; where for each LLU that enters the system, is improved by 2816 l.Ha-1year. Of the 34 variables analyzed, those that determined the productivity of the dairies were: total litters per lactation (33.3%), milking cows (17.7%), Ha productive (11.0%), liters per Ha year (7.8%), supplements (5.3%) and pasture production DM kg.Ha-1 (4.5%). Four grazing-based production systems were identified that depend critically on concentrated supplements with severe asymmetries in racial components that negatively affect productivity.