Background

Estimation of the quantity of colostral IgG or serum IgG absorbed following ingestion of colostrum by calves is essential for monitoring the effectiveness of colostrum feeding practices on dairy farms. Milk total solids concentrations determination is a critical part of quality assessment of nonsaleable whole milk prior to feeding to calves. To date, on-farm methods to assess colostral IgG, serum IgG or milk total solids concentrations have been performed separately with various instruments. The objective of this study was to evaluate the diagnostic performance of a single electronic, hand-held refractometer for assessing colostral and serum IgG concentrations and milk total solids in dairy cattle. Colostral IgG, serum IgG and milk total solids concentrations were determined by the refractometer. Corresponding analysis of colostral and serum IgG concentrations were determined by radial immunodiffusion (RID) while milk total solids were determined by spectrophotometry. Sensitivity and specificity of the refractometer for colostrum and serum samples were calculated as determined by RID. Sensitivity and specificity of the refractometer for milk samples was calculated as determined by spectrophotometry.

Results

The sensitivity of the refractometer was 1 for colostral IgG, serum IgG and milk total solids determinations. Specificity of the refractometer was 0.66, 0.24 and 0 for colostral IgG, serum IgG and milk total solids determinations, respectively. The refractometer underestimated colostral IgG, serum IgG and milk total solids concentrations compared to the concentrations determined by RID or spectrophotometry.

Conclusions

The refractometer was an acceptable, rapid, convenient on-farm method for determining colostral IgG and milk total solids. The refractometer was not an acceptable method for determination of serum IgG concentrations as it severely underestimated the serum IgG concentrations.

In calves, passive immunity of immunoglobulins can be acquired through ingestion of colostrum or colostrum replacers. Plasma can been used to supplement immunoglobulins in healthy or sick calves. Serum half-life of colostral derived immuglobulin G (IgG) is estimated to be 20 days. Half-life of IgG is important in determining response to antigens and timing of vaccination in calves. To date studies evaluating half-life of colostrum replacer or plasma derived IgG are lacking. The objectives of this study were to compare the serum half-life of IgG derived from colostrum, colostrum replacer and plasma in dairy calves reared up to 35 days of age. Thirty Jersey calves were randomly assigned to receive colostrum or colostrum replacer by oroesophageal tubing or plasma by intravenous administration. Serum samples were collected at 2, 5, 7, 10, 14, 21, 28 and 35 days. Serum IgG concentrations were determined by radial immunodiffusion. The results indicated that half-life for IgG in colostrum fed (28.5 days) or plasma transfused calves (27.3 days) was longer than colostrum replacer fed calves (19.1 days). Further studies are required to evaluate pathogen specific immunoglobulins in order to recommend vaccination timing in calves fed colostrum replacers.

Background

Factors influencing fertility desires among HIV-infected individuals remain poorly understood. With new recommendations for universal HIV treatment and increasing antiretroviral therapy (ART) access, we sought to evaluate how access to early ART influences fertility desires among HIV-infected ART-naïve women.

Methods

Semi-structured in-depth interviews were conducted with a select subgroup of 20 HIV-infected ART-naïve women attending one of 13 HIV facilities in western Kenya between July and August 2014 who would soon newly become eligible to initiate ART based on the latest national policy recommendations. The interviews covered four major themes: 1) definitions of family and children's role in community; 2) personal, interpersonal, institutional, and societal factors influencing fertility desires; 3) influence of HIV-positive status on fertility desires; and 4) influence of future ART initiation on fertility desires. An iterative process of reading transcripts, applying inductive codes, and comparing and contrasting codes was used to identify convergent and divergent themes.

Results

The women indicated their HIV-positive status did influence-largely negatively-their fertility desires. Furthermore, initiating ART and anticipating improved health status did not necessarily translate to increased fertility desires. Instead, individual factors, such as age, parity, current health status, financial resources and number of surviving or HIV-infected children, played a crucial role in decisions about future fertility. In addition, societal influences, such as community norms and health providers' expectations of their fertility desires, played an equally important role in determining fertility desires.

Conclusions

Initiating ART may not be the leading factor influencing fertility desires among previously ART-naïve HIV-infected women. Instead, individual and societal factors appear to be the major determinants of fertility desires among these women.

The rumen is a complex ecosystem that plays a critical role in our efforts to improve feed efficiency of cattle and reduce their environmental impacts. Sequencing of the 16S rRNA gene provides a powerful tool to survey the bacterial and some archaeal. Oral stomach tubing a cow to collect a rumen sample is a rapid, cost-effective alternative to rumen cannulation for acquiring rumen samples. In this study, we determined how sampling method (oral stomach tubing vs cannulated grab sample), as well as rumen fraction type (liquid vs solid), bias the bacterial and archaeal communities observed. Liquid samples were further divided into liquid strained through cheesecloth and unstrained. Fecal samples were also collected to determine how these differed from the rumen sample types. The abundance of major archaeal communities was not different at the family level in samples acquired via rumen cannula or stomach tube. In contrast to the stable archaeal communities across sample type, the bacterial order WCHB1-41 (phylum Kiritimatiellaeota) was enriched in both liquid strained and unstrained samples as well as the family Prevotellaceae as compared to grab samples. However, these liquid samples had significantly lower abundance of Lachnospiraceae compared with grab samples. Solid samples strained of rumen liquid most closely resembled the grab samples containing both rumen liquid and solid particles obtained directly from the rumen cannula; therefore, inclusion of particulate matter is important for an accurate representation of the rumen bacteria. Stomach tube samples were the most variable and were most representative of the liquid phase. In comparison with a grab sample, stomach tube samples had significantly lower abundance of Lachnospiraceae, Fibrobacter and Treponema. Fecal samples did not reflect the community composition of the rumen, as fecal samples had significantly higher relative abundance of Ruminococcaceae and significantly lower relative abundance of Lachnospiraceae compared with grab samples.

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.

Introduction

Intimate partner violence and food insecurity are both structural drivers of HIV acquisition, care, and treatment, but little is known about how the 2 conditions intersect in the lives of those already living with HIV.

Methods

This study examined cross-sectional baseline data (collected in January 2016-December 2017) from an ongoing trial in southwestern Kenya. Trained interviewers asked enrolled participants living with HIV aged 18-60 years about household food insecurity (using the Household Food Insecurity Access Scale), intimate partner violence (using an adapted WHO multicountry study instrument), and sociodemographics. Negative binomial regression was used to examine the association between food insecurity and partner violence victimization (among women) or perpetration (among men). Secondary data were analyzed in August 2019-March 2020.

Results

Of 720 participants, more than half of women reported experiencing intimate partner violence (57.6%) and most men reported perpetrating it (58.4%). Participants reporting any partner violence had higher Household Food Insecurity Access Scale scores (21.8) compared with those reporting no violence (21.3, p=0.02). Each categorical change in food insecurity (mild, moderate, severe) was associated with a 41% increased risk of an additional partner violence episode. In models controlling for relationship status, wealth, season of interview (lean versus not lean), and baseline physical health, each 1-point increase in food insecurity was associated with a 6% higher risk of violence victimization among women and 4% greater risk of men perpetrating partner violence.

Conclusions

This study highlights the interconnected nature of intimate partner violence and food insecurity among women and men living with HIV. This relationship suggests that enhancing food security may be a useful intervention strategy to prevent intimate partner violence and improve HIV-related health outcomes.

Introduction

To improve retention on HIV treatment in Africa, public health programs are promoting a family of innovations to service delivery-referred to as "differentiated service delivery" (DSD) models-which seek to better meet the needs of both systems and patients by reducing unnecessary encounters, expanding access, and incorporating peers and patients in patient care. Data on the relative desirability of different models to target populations, which is currently sparse, can help guide prioritization of specific models during scale-up.

Methods

We conducted a discrete choice experiment to assess patient preferences for various characteristics of treatment services. Clinically stable people living with HIV were recruited from an HIV clinic in Kisumu, Kenya. We selected seven attributes of DSD models drawn from literature review and previous qualitative work. We created a balanced and orthogonal design to identify main term effects. A total of ten choice tasks were solicited per respondent. We calculated relative utility (RU) for each attribute level, a numerical representation of the strength of patient preference. Data were analyzed using a Hierarchical Bayesian model via Sawtooth Software.

Results

One hundred and four respondents (37.5% men, 41.1 years mean age) preferred receiving care at a health facility, compared with home-delivery or a community meeting point (RU = 69.3, -16.2, and -53.1, respectively; p << 0.05); receiving those services from clinicians and pharmacists-as opposed to lay health workers or peers (RU = 21.5, 5.9, -24.5; p < 0.05); and preferred an individual support system over a group support system (RU = 15.0 and 4.2; p < 0.05). Likewise, patients strongly preferred longer intervals between both clinical reviews (RU = 40.1 and -50.7 for 6- and 1-month spacing, respectively; p < 0.05) and between ART collections (RU = 33.6 and -49.5 for 6- and1-month spacing, respectively; p < 0.05).

Conclusion

Although health systems find community- and peer-based DSD models attractive, clinically stable patients expressed a preference for facility-based care as long as clinical visits were extended to biannual. These data suggest that multi-month scripting and fast-track models best align with patient preferences, an insight which can help prioritize use of different DSD models in the region.