On-farm Testing Research Articles

Blood calcium as a prognostic indicator of success after surgical correction of left displaced abomasum

Subclinical hypocalcemia, a reduction in blood calcium concentrations without apparent clinical signs of milk fever, occurs in 25 to 50% of early-postpartum dairy cows. Research has shown that these cows are at an increased risk of additional early-lactation diseases, including left displaced abomasum (LDA), compared with their normocalcemic counterparts. However, no work has assessed the association of total calcium (tCa) concentration at the time of LDA correction with subsequent milk yield and survival within the herd. Pending future development of an economical and accurate on-farm test for hypocalcemia, the ability to assess LDA prognosis after surgical correction based on precorrection blood tCa concentration is of interest to practitioners. Therefore, our objective was to determine the association of blood tCa concentration at the time of LDA surgical correction with milk yield and herd removal in the 60 d after correction. Nine bovine practitioners, located in New York State, were involved in sample collection from 17 herds for this prospective cohort study. Immediately following LDA diagnosis and before surgical correction, blood samples were collected from 152 dairy cows within the first 30 d in milk for serum tCa determination. The association of tCa with milk yield (n = 110) and herd removal (n = 127) in the first 60 d after LDA surgical correction was analyzed using repeated-measures ANOVA and a generalized linear mixed model, respectively, controlling for parity and days in milk at LDA surgical correction and the random effect of herd or practitioner. We found no evidence to support an association of tCa at time of LDA diagnosis with subsequent milk yield, and when cows were grouped by median tCa into low and high groups (tCa ≤2.1 and >2.1 mmol/L, respectively), subsequent milk production was similar (39.4 ± 1.6 and 40.1 ± 1.4 kg/d for low and high, respectively). Furthermore, we found no evidence to support an association of tCa at time of LDA diagnosis with the odds of herd removal (odds ratio = 0.6; 95% confidence interval = 0.4–1.7). Therefore, our study provided no clear evidence to support the association of tCa at time of LDA diagnosis and correction with either milk yield or herd removal during the 8 wk after correction. However, it did demonstrate low to extremely low tCa concentration in cows with LDA. Whether calcium supplementation would improve health and production outcomes in these cows is unclear and worth investigating further.

Effects of a mastitis treatment strategy with or without on-farm testing

The etiology of mastitis is crucial information to use antimicrobials prudently for control and treatment. This study aimed to evaluate the effects of mastitis diagnosis and treatment strategies with on-farm testing, on cure, new intramammary infections (IMI), somatic cell count (SCC), and antimicrobial use, compared with farmers' current diagnosis and treatment strategies. The on-farm tests used, CHROMagar Mastitis (CHROMagar, Paris, France) and Minnesota Easy Culture System II Tri-plate (University of Minnesota, St. Paul, MN), both had etiological groups of IMI as result, being gram-positive growth, gram-negative growth, or culture negative. Two randomized controlled trials were conducted on 15 herds: trial 1 prospectively enrolled 155 cows with clinical mastitis, and trial 2 cross-sectionally included 78 cows with subclinical mastitis. In both trials, cows were randomly distributed over 3 equal-sized groups: a test group using CHROMagar, a test group using Minnesota, and a control group not using on-farm tests. Farmers decided whether or not to treat, and which antimicrobial treatment would be applied, using information available on the day of enrollment (control group), complemented with the on-farm test result 1 d after enrollment (both test groups). For clinical mastitis, an antimicrobial treatment was given in 58% of cases that used CHROMagar, in 80% that used Minnesota, and in 86% of the controls. For subclinical mastitis, an antimicrobial treatment was given in 50% of cases that used CHROMagar, in 54% that used Minnesota, and in 4% of the controls. Bacteriological cure rate of clinical mastitis was lowest in the CHROMagar group [odds ratio 0.18 (95%CI 0.03-0.99)] compared with the controls. Using the Minnesota on-farm test for subclinical mastitis diagnosis and treatments resulted in fewer new IMI on d 21 [odds ratio 0.06 (95%CI 0.00-0.74)] compared with the controls. Clinical cure rate, percentage of new IMI, and SCC on d 21 of clinical mastitis were comparable among the groups. Using on-farm tests in farmers' decision-making process resulted in more treatments in accordance with the etiology of mastitis than without on-farm testing. A diagnosis and treatment strategy with on-farm testing is advised in cows with clinical mastitis to enhance prudent antimicrobial use. For subclinical mastitis, however, on-farm testing may lead to an unacceptable increase in use of antimicrobials and thus should not be advised as the common approach.

Yield performance of Niger and their improved variety in Mandla district under northern hill of Chhattisgarh zone of Madhya Pradesh

An On Farm Testing (OFT) trial was carried out to compare the yield performance of niger variety at farmers’ field in Mandla district (Northern Hill of Chhattisgarh Zone), Madhya Pradesh, India during Kharif season 2015 and 2016. All the improved package and practices (IP) was applied with improved Niger variety (JNS-9) while local farmer’s variety was as it is with their existing farmers’ practices (FP). The results revealed that the average seed yield was 856.50 kg/ha in IP while it was 389.00 kg/ha in FP. The average seed yield was increased by 120.26% in the IP over the FP. The average extension gap was recorded 467.50 kg/ha over the FP. The average technology gap in IP of Niger over the FP was recorded 143.50 kg/ha whereas, average technology index was 14.35%. The average cost of cultivation under IP was Rs.7840.00/ha with net return of Rs. 26420.00/ha and B:C ratio 3.37 while it was Rs. 5586.00/ha with net return Rs. 9974.00/ha and B:C ratio 1.80 under FP. On an average Rs. 16446/ha was recorded as additional income which significantly attributed due to the adoption of recommended package and practices including improved Niger variety.

Technical note: Evaluation of a commercial on-farm milk leukocyte differential tester to identify subclinical mastitis cases in dairy cows

The objective of this study was to validate the precision and accuracy of a milk leukocyte differential tester to identify subclinical mastitis cases in dairy cows. Milk samples from individual quarters (n = 320) of 80 Holstein cows were aseptically collected and analyzed in this study. Each sample was divided into 2 replicate samples after mixing. One replicate was analyzed for somatic cell count (SCC) using the current gold standard of flow cytometry immediately after milking. The second sample was evaluated using the on-farm milk leukocyte differential tester directly after milking, where total leukocyte count (TLC; cells/mL) was obtained. The SCC and TLC were used to calculate somatic cell score (SCS) and TLC score [TLS = log2 (TLC/100,000) + 3]. Two subclinical mastitis thresholds were set: >200,000 (low) and >400,000 (high) cells/mL. First, precision was determined between the 2 methods. Total leukocyte count and calculated TLS from the milk leukocyte differential device were compared with the gold standard using correlation and regression coefficient of determination analyses. Correlation coefficients (r) were 0.97 for TLC and SCC and 0.90 for TLS and SCS. The coefficient of determination for regression (R2) was 0.94 for TLC and SCC and 0.80 for TLS and SCS. Slopes of regression for scores and measures were 0.36 [95% confidence interval (CI): 0.35-0.37] and 0.69 (CI: 0.65-0.73), respectively; both were significantly different from 1. Sensitivity, specificity, and diagnostic accuracy were calculated for correct diagnosis of the 2 SCC thresholds using the gold standard as reference. The sensitivity of the on-farm test was 58% (95% CI: 44 to 71%) and 73% (95% CI: 56 to 86%) for the low and high thresholds, respectively. The specificities for the on-farm test were 100% (95% CI: 99 to 100%) and 100% (95% CI: 98 to 100%) for the low and high thresholds, respectively. Subclinical diagnosis accuracies were 93% (95% CI: 89 to 95%) and 96% (95% CI: 92 to 98%) for the low and high thresholds, respectively. The on-farm milk leukocyte differential tester was precise but not overall accurate for total cell counts; it had high specificity and accuracy for diagnosis compared with a standard diagnostic tool. These results suggest that the tested system is a promising technology to detect subclinical mastitis on-farm.

Farmer involvement in agro-ecological research: organic on-farm wheat variety trials in Hungary and the Slovakian upland

The acreage of organic farming is constantly increasing in Hungary. The cultivation of cereals—and within it—the production of winter wheat is of main importance in organic field crop production. Besides the challenges of global climate change, various difficulties are known, such as the inadequate variety assortment, lack of knowledge on the performance of varieties under organic conditions and often low quality of the seeds sown. As official post-registration variety trials only exist under conventional farming conditions in Hungary, the Hungarian Research Institute of Organic Agriculture (ÖMKi) started participatory organic on-farm variety tests in 2012, with the involvement of volunteer farmers all over the country. Over the past 7 years, nearly 60 wheat varieties and more than 20 farms have been included in the tests. The aim of the study was to find the most suitable varieties for high-quality organic wheat production and exclude inappropriate varieties for respective production regions. Results demonstrated that there is great potential in choosing varieties best suited to regional environmental conditions and that it is possible to achieve both high yield and excellent quality also in organic farming when adopting the appropriate varieties. The use of varieties, which were proven to be disease tolerant or resistant, can significantly contribute to safer organic production. The comparisons between the performance of varieties indicated that organic breeding has a great role in all of the above matters.

Effect of foliar spray of water- soluble fertilizer on growth and yield of chilli (Capsicum annuum)

The experiment was conducted to find out the effect of foliar application of water soluble fertilizers on growth and yield of chilli (Capsicum annuum L.) during 2015–16, 2016–17 and 2017–18 at Bharatpur, Rajasthan. The application of recommended dose of fertilizers-NPK @ 70:48:50) + water-soluble fertilizers (polyfeed NPK-19:19:19) @1% at 45 and 75 days after transplanting recorded higher yield of green chilli (93 q/ha) as compared to the control (84 q/ha). There was 10.71% increase in yield over the control.The technology gap in productivity (7 q/ha) was computed. The technology index value (7.53%) was recorded. The results indicated the gap existed in the potential yield and demonstration yield is due to soil fertility and weather conditions. By conducting on-farm testing of proven technology of nutrient management, yield potential of chilli can be increased. This will substantially increase the income as well as the livelihood of farming community.

Assessment of IPM module against pod borer complex in pigeon pea (Cajanus cajan L.)

On-farm testing of IPM module in pigeon pea against pod borer complex was carried out on farmers’ field of two villages of district Jaunpur by KVK Jaunpur- 1 during 2018 and 2019 with three components viz., IPM module, farmers’ practice, and untreated check without plant protection measures. The IPM interventions viz., growing pod borer tolerant variety, two rows of maize as a border crop, installation of pheromone traps and bird perches with the application of botanical based insecticide azadirachtin 1% at the vegetative stage as an oviposition deterrence, application of chlorantraniliprole, and flubendiamide at critical stages of pod borer appearance during bud initiation and flowering stages. The reduction in the larval population and pod damage in IPM treated plots resulted in a significant increase in grain yield (1525 kg/ha) followed by farmers’ practice (1195 kg/ha) and in untreated check (857 kg/ha) The increase in grain yield was due to an additional investment of Rs.4100/-ha towards IPM module and farmers’ practice (Rs.2600/-ha). The excess expenditure incurred resulted in the highest net return of Rs.47550/-ha in the IPM module as compared to farmers' practice and in untreated check resulted in the lowest net return of Rs.18250/-ha.

Genotype by Environment interactions for egg number and egg weight of five dual-purpose chicken breeds in different zones of Oromia region in Ethiopia

The African Chicken Genetic Gain (ACGG) project (https://africacgg.net/) aims at backyard poultry optimization by commercial dual-purpose breeds introduction into Africa. To measure benefits, genotype by environment interaction (GxE) analysis provides guidance while predicting environmental effects on production traits of breeds. A survey among Ethiopian poultry smallholders showed egg sale being the most important purpose of keeping village chickens in Oromia. Data was available about laying of 894 ACGG chickens in Oromia. Hence current research questions were: 1) Does GxE take place? 2) Which breed performs best regarding laying and in which environment within Oromia? Traits investigated were egg number and egg weight of five breeds (S-RIR, Sasso, Horro, Kuroiler and Koekoek) located in three zones (East Hararge, East and West Shoa) and 5 districts (Adami Tulu, Bako Tibe, Dano, Dugda and Haromaya) in Oromia. Observations were taken as group measure performing weighted analyses. GxE was only present for egg number with magnitude strongest for zone. S-RIR performed best for both traits in both environments, except Kuroiler performing better in East Shoa for egg number and Koekoek for egg weight. This indicates success of crossbreed S-RIR. Sasso and Horro performed worst supported by previous research for Horro but not Sasso. Low precipitation in East Shoa caused bigger distance in egg number predictions, being higher for S-RIR and lower for Horro and Sasso compared to West Shoa. Apart from these final conclusions, social context of breeding and data collection difficulties should not be forgotten. Just like relevance of other performance trait analyses.

On-farm testing of dairy calves’ avoidance response to human approach: Effects of sex, age and test order

AbstractHuman approach tests are generally accepted as valid measures of the human-animal relationship and hence are widely included in on-farm welfare assessment protocols. Most measures of avoidance response to human approach in production animals have been developed and tested under experimental conditions rather than on commercial farms, thereby making the results less relevant for operational on-farm animal welfare assessment. By contrast, the current study was conducted on calves in their home pens. On 110 Norwegian dairy farms, 548 group-housed calves (aged 22-288 days) were tested individually for their behavioural response to an unfamiliar human approach by a single test person. To conduct the test, the respective calf manager administered concentrates to the manger, followed by the test person who approached each animal in turn in a standardised manner. The avoidance response of the individual calf was categorised as 0 to 5 (maximal to no avoidance) in reaction to an attempted approach and head touch by the test person. The statistical analyses showed that heifer calves were more avoidant compared to bull calves, as were younger bulls compared to older bulls, and that overall avoidance increased in calves that were not tested first.

Veterinary Diagnostic Practice and the Use of Rapid Tests in Antimicrobial Stewardship on UK Livestock Farms.

In this paper we consider the shifting role, practice and context of veterinary diagnosis in addressing concerns over what is, in the context of the growing threat of antimicrobial resistance, considered unnecessary or excessive antimicrobial medicine use in UK livestock farms. With increasing policy and regulatory interest in diagnostic practices and technologies, coupled with an expanding focus on the development and deployment of new rapid and point-of-care on-farm diagnostic testing, this paper investigates current diagnostic practices amongst veterinarians working on dairy, pig and poultry farms in Great Britain (England, Wales, and Scotland) and, more specifically, veterinarians' use and perceptions of new and emerging rapid and point-of-care diagnostic tests. Drawing on a series of 30 semi-structured interviews with farm animal veterinary professionals across the three sectors, this paper examines the manner in which such tests are both used and anticipated in clinical farm animal veterinary practice and the possible impact rapid test technologies might have on broader farm animal health management and disease control. Analysis of the transcribed interviews reveals a number of complexities around the use of rapid and point-of-care diagnostic tests. The relative rapidity and simplification of such tests, facilitating immediate treatment responses, is held in balance against both the accuracy and the more detailed and documented procedures of established laboratory testing routes. In situations of multifaceted on-farm etiologies, respondents maintained that rapid tests may offer restricted diagnostic capabilities, though in other situations they were found to offer ready confirmation of disease presence. A third complexity arising from the growth of rapid and point-of-care testing and revealed in this study relates to the shifting distribution of responsibilities in animal health care within contemporary food chains. The growing availability of rapid and point-of-care tests effectively diversifies the range of diagnostic actors with consequences for the flow of diagnostic and disease information. The veterinarians in this study identified areas where new rapid and point-of-care tests would be of particular value to them in their clinical practice particularly in addressing concerns over inappropriate antimicrobial use in animal treatment. However, despite the considerable policy advocacy on rapid and point-of-care tests as key tools in shifting diagnostic practice and reducing unnecessary antimicrobial use, veterinarians in this study, while recognizing the potential future role of such tools and technologies, nonetheless viewed diagnostic practice as a far more complex process for which rapid tests might constitute only a part.

Implementation of a targeted mastitis therapy concept using an on-farm rapid test: antimicrobial consumption, cure rates and compliance

BackgroundAim of the present study was to investigate the implementation of a targeted therapy (tLCT) concept under real-life circumstances, taking both pathogen-related and animal-related factors into account. The reduction of...

Blood calcium as a prognostic indicator of left-displaced abomasum postsurgical correction success

Subclinical hypocalcemia, a reduction in blood calcium concentrations without apparent clinical signs of milk fever, occurs in 25 to 50% of early-postpartum dairy cows. Compared to their normocalcemic counterparts, research has shown these cows are at an increased risk of additional early-lactation diseases, including left-displaced abomasum (LDA). However, no work has assessed the association of total calcium (tCa) concentration at the time of LDA correction on subsequent milk yield and survival within the herd. Pending future development of an economical and accurate on-farm test for hypocalcemia, the ability to assess LDA prognosis post-surgical correction based on pre-correction blood tCa concentration is of great interest to practitioners. Therefore, our objective was to determine the association of blood tCa concentration at the time of LDA surgical correction on milk yield and removal from herd in the 60 d post-correction.

Performance evaluation of a newly designed on-farm blood testing system for determining blood non-esterified fatty acid and β-hydroxybutyrate concentrations in dairy cows

The objective of this study was to evaluate a newly designed on-farm blood testing system (OFBTS) for monitoring blood concentrations of non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHBA) in dairy cows. Blood samples from 230 Holstein dairy cows between −86 and 343 days in milk were collected. A drop of whole blood was used to determine NEFA and BHBA using the OFBTS. Plasma from the remaining blood was used to determine both analytes using a commercial kit (gold standard). In the repeatability of the OFBTS, the intra-assay CV for NEFA and BHBA were 1.3% and 4.5%, and the inter-assay CV were 1.8% and 2.9%, respectively. The slope and coefficient of determination of OFBTS analysis of NEFA compared to the gold standard were 0.92 and 0.94. Those for BHBA were 0.94 and 0.98. Mean of the difference between the gold standard laboratory assays and OFBTS of NEFA and BHBA were 0.021 and 0.019, respectively. However, the bias became substantial for NEFA in the higher concentration ranges (>1.2 mEq/L). The sensitivity and specificity of NEFA were 93.2% and 99.4% at a cutpoint of 0.4 mEq/L, and 87.9% and 100% at 0.6 mEq/L. Those of BHBA were 86.2% and 99.0% at a cutpoint of 1.0 mM, and 94.7% and 99.5% at 1.2 mM. The reaction time for the NEFA to reach 0.6 mEq/L was 7 min. The BHBA reaction reached 1.2 mM within 2 min. In conclusion, the OFBTS has excellent performance for evaluating blood NEFA or BHBA concentrations.

Metabolic disease testing on farms: epidemiological principles

Background: Although many clinical metabolic diseases have been successfully controlled in modern dairy herds, subclinical metabolic diseases are often prevalent and associated with significant economic losses. Given the absence of...

Evaluation of adenosine triphosphate testing for on-farm cleanliness monitoring compared to microbiological testing in an empty pig farrowing unit.

Careful cleaning and disinfection of pigpens is essential to prevent disease spread and avoid the resultant economic losses. Hygiene in pigpens is generally evaluated by visual monitoring supplemented with bacteriological monitoring, which includes counting the total aerobic bacteria (TAB) and/or fecal indicator bacteria (FIB). However, these methods present drawbacks such as time and labor requirements. As adenosine triphosphate (ATP) is ubiquitous in all living organisms including microorganisms, this study aimed to directly compare the results of microbial assessment and ATP quantification, and to suggest possible detailed application methods of the ATP test for hygiene evaluation in pigpens of a farrowing unit. Before and after standard cleaning procedures, samples were collected from the floor corner, floor center, and feeding trough of four pigpens at different time points. No FIB were detected and both the TAB and ATP levels were significantly decreased in the floor center area after cleaning. FIB were continuously detected after cleaning and disinfection of the floor corners, and there was no significant ATP level reduction. The feeding trough did not show any significant difference in these values before and after cleaning, indicating insufficient cleaning of this area. The levels of TAB and ATP after cleaning were significantly correlated and the average ATP value was significantly lower in the absence of FIB than in their presence. In the absence of standard references, a more thorough hygiene management could be achieved evenly by supplementing cleaning or disinfection based on the lowest ATP results obtained at the cleanest test site, which in the present study was the floor center. Overall, these results indicate that the on-farm ATP test can be used to determine the cleanliness status, in addition to visual inspection, as an alternative to laboratory culture-based testing for the presence of microorganisms.

Conservation Agriculture and Integrated Pest Management Practices Improve Yield and Income while Reducing Labor, Pests, Diseases and Chemical Pesticide Use in Smallholder Vegetable Farms in Nepal

Improving smallholder vegetable farms are critical for improving food security and livelihoods of people in low-income countries. Vegetable production is labor intensive and prone to pests and diseases. Conservation agriculture (CA) and integrated pest management (IPM) practices provide options to increase yields and minimize the use of chemical pesticides. We compared integration of CA and IPM practices (improved alternative system) with farmers’ traditional practice (conventional system) under replicated on-farm tests in four different locations (Lalitpur, Banke, Surkhet, and Dadeldhura) in Nepal. Data on yield, benefit–cost ratio (B:C), labor requirement, insect and disease infestation, and pesticide sprays on five major vegetable crops (tomato, cucumber, bitter gourd, cabbage, cauliflower) were measured. In tomatoes, cucumbers, and bitter gourds, the improved alternative system produced a significantly higher yield, greater benefit-cost ratio, reduced labor, decreased the infestation of pests and diseases, and required fewer pesticidal sprays. Average yield and net income were superior in cabbages and cauliflowers, but nonsignificant. Improved alternative system for all the vegetables were sprayed significantly fewer times than the conventional system. Overall, the improved alternative system for vegetable crops contributed not only to the improved income and livelihoods of people, but also can improve environment and human health due to the reduced use of pesticides. Further research on scaling these improved alternative practices through appropriate farmer organizations, and government and non-government actors can enhance the adoption of CA and IPM practices by smallholder vegetable producers.

Technical note: Evaluation of a colorimetric point-of-care test for measuring urine ammonium concentration in periparturient dairy cattle

Urine ammonium concentration ([NH4+]) provides a clinically useful indicator of the magnitude of nutritionally induced systemic acidification in dairy cattle when urine pH < 6.1. The objective of this study was to evaluate the analytical performance of a low-cost point-of-care colorimetric test in measuring urine [NH4+] in dairy cattle consuming an acidogenic ration. A method comparison study was performed using 154 urine samples from 43 periparturient Holstein-Friesian cows. We compared urine [NH4+] measured by an indophenol blue colorimetric test (MColortest, Merck KGaA, Billerica, MA; test method) with levels measured by formaldehyde titration (reference method). Diagnostic performance was evaluated using Pearson correlation coefficient (r), Passing-Bablok regression, Bland-Altman plot, and binary logistic regression. Urine [NH4+] measured by the colorimetric test was strongly correlated (r = 0.98) with urine [NH4+] measured by formaldehyde titration. Method comparison studies indicated that the colorimetric test provided acceptable test performance when urine [NH4+] < 80 mmol/L. Logistic regression analysis indicated that the area under the receiver operating characteristic curve for the colorimetric ammonium test was high at 0.985 when used to identify formaldehyde titration [NH4+] > 10 mmol/L, equivalent to urine pH <6.1. At the optimal cut point ([NH4+] > 11 mmol/L) for the colorimetric test, sensitivity = 0.94, specificity = 0.97, positive likelihood ratio = 27.6, and κ = 0.89, indicating excellent test performance. We conclude that the indophenol blue colorimetric test provided an accurate, low-cost, and practical on-farm test for measuring urine [NH4+] in diluted urine samples from dairy cattle consuming an acidogenic ration.

Use of on-farm milk progesterone information to predict fertility outcomes in dairy cows subjected to timed artificial insemination

The objectives of this study were to evaluate the use of a qualitative on-farm milk progesterone test to predict non-pregnancy in dairy cows. Lactating Jersey cows (n = 752) were subjected to the 5-d Cosynch-72 protocol for timed artificial insemination (AI; d -8 GnRH, d -3 and -2 PGF2α, d 0 GnRH and timed AI). Milk was sampled on d -3, 0, 7, and 28 relative to timed AI, and progesterone concentrations were assessed using a lateral flow immunochromatographic test. Samples were classified into 3 groups indicative of high (hP4; test line not visible or lighter than reference), intermediate (iP4; test line similar to reference), and low (lP4; test line darker than reference) progesterone concentrations. Blood was sampled from a subset of cows (n = 50) on d -3, 0, 7, and 28 relative to timed AI, and plasma progesterone concentrations were determined by RIA. Cows were observed daily for signs of estrus based on removal of tail paint. Pregnancy was diagnosed by ultrasonography on d 34 and 62 after AI. Plasma progesterone concentrations across all time points were greater for hP4 (3.13 ± 0.20 ng/mL) followed by iP4 (1.12 ± 0.27 ng/mL) and lP4 (0.38 ± 0.23 ng/mL). Cows in lP4 on d -3 had lesser pregnancy per AI (P/AI) compared with iP4 and hP4 (17.4, 38.3, and 37.2%, respectively). For measurements performed on the day of AI (d 0), lP4 cows had greater P/AI compared with hP4 and iP4 (34.8, 0.0, and 15.6%, respectively), and the risk of pregnancy loss tended to be greater for iP4 compared with lP4. Cows in lP4 on d 7 after AI had lesser P/AI than those in iP4 and hP4 (12.0, 34.0, and 37.7%, respectively). Cows classified as lP4 on d 28 had the least P/AI on d 62 followed by iP4 and then hP4 (0.8, 9.2, and 59.4%, respectively) and were at the greatest risk for pregnancy loss (lP4 = 74.6%, iP4 = 8.4%, hP4 = 7.1%). Sensitivity and specificity to predict non-pregnancy on d 62 were 0.86 and 0.32 (d -3), 0.95 and 0.15 (d 0), 0.93 and 0.23 (d 7), and 0.99 and 0.53 (d 28), respectively. On-farm milk progesterone profiling using a lateral flow immunochromatographic test was able to identify cows without functional corpus luteum and to predict fertility outcomes following timed AI.

Fabrication of penicillin G portable microbiological test plate for on-farm antibiotic residues in milk

Antibiotic residues in animal-derived food products such as milk pose a potential health risk to consumers. A portable antimicrobial screening test plate was fabricated particularly for on-farm testing of milk. A cold-water soluble compound gelling agent composed of guar gum (GG) and konjac glucomannan (KG) was prepared and its properties were optimized for enhancing performance of the test plate. A ratio of 4:6 (GG:KG) showed improved gel strength, cohesiveness, transmittance, and water diffusion of the compound gel. Microbial colony number and size were also increased. The test plate displayed a minimum inhibition concentration of 4 µg/L penicillin G and clearer zone of inhibition. Detection time was also significantly reduced to approximately 9–15 h compared to the conventional agar plate method. The plastic film test plate with optimized compound gel demonstrated tremendous potential for detection of antibiotics in milk.

Crowdsourcing Knowledge: An Extension Approach for Remunerative and Sustainable Home Garden Farming Systems in Kerala

Kerala has pioneered development models through farmer participatory approaches. Involving the grassroots in scientific studies can help improve crop variety adoption and refined technology recommendations. Participatory tools like Participatory Rural Appraisal (PRA), Participatory Technology Development (PTD), On Farm Testing (OFT), Front Line Demonstrations (FLD) and Participatory Breeding Programmes (PBP) are all time-tested examples of its successful use in researches. Crowdsourced citizen science approach called tricot – ‘triadic comparisons of technologies’ is popular today, where farmers are made to adopt three crop varieties or technologies randomly assigned to them from a broader set of varieties/technologies for final choice aimed at continuous adoption. The results of this study conducted during 2019-2020 revealed that more than 80% of the farmers fully adopted the technology prescribed in the checklist as a result of crowdsourcing knowledge. The results on attitude of farmers towards crowdsourcing revealed that majority of the farmers posessed favourable attitude towards crowdsourcing approach.