High Number Of Animals Research Articles

Cruelty toward Dogs and Cats in the Republic of Serbia during a 10-Year Period.

The aim of the study was to point out the importance of recognizing non-accidental injuries (NAI) and to highlight the importance of reporting such cases, as well as prosecuting the perpetrators, in order to detect potentially existing violence or prevent future violence in society. A total of 338 dogs and 54 cats were submitted for necropsy. Out of 338 dogs examined, 175 (51.8%) died due to non-natural cause of death, 122 from natural causes (36.1%), and 35 (10.3%) due to accidental injuries, and in 6 cases (1.8%) the cause and manner of death were undetermined due to advanced post-mortal changes. Out of 54 examined cats, 21 died due to non-natural causes (38.9%) and the same number of cats died due to natural causes. The prevalence of accidental injuries resulting in death were 20.4% (n = 11) and in 1.8% (n = 1) the manner of death remained indeterminate. The high number of animals confirmed to have died from unnatural causes in this study highlights the need for greater involvement from the police, prosecution, and society as a whole to reduce the number of violent animal deaths in the future.

Impact of different stall layouts with robotic milking systems on the behavioral pattern of multiparous cows

The present study aimed to compare the efficiency of different pens and animal flow configuration layouts in freestall pens using a robotic milking system (RMS) with guided flow based on the behavioral patterns of multiparous lactating Holstein dairy cows in a commercial farm. The behavior of 24 cows in freestall pens was evaluated, divided into 4 different stall configurations: original (OR), conversion (CVS), toll-booth I (TBI), and toll-booth II (TBII), each featuring distinct circulation layouts with different configurations of location, position, and number of guided-flow RMS equipment, feed bunk, water trough, commitment pen, sand beds, sorting gates, and one-way gate. Six multiparous cows, parity 2 or 3, with an average (± SD) of 180 ± 20 DIM, were randomly selected from each freestall pen for focal assessment of behavioral patterns. The location, position, and behavior of each animal were recorded in a field ethogram, with individual sequences recorded at 15-min intervals using the focal method during 6 nonconsecutive 10-h periods in each pen, and the proportion of observed time for each behavior was assessed. The pens differed in the number of available milking robots (1, 2, or 3), the number of animals per robot, the quantity and orientation of smart doors, and the placement of feed bunks, water troughs, and sand beds. A completely randomized experimental design was used to compare the 4 stalls, with a nonparametric Kruskal-Wallis test, in which the medians of the treatments were then compared with the Dunn test at a significance level of 5%, using the Minitab software. The behavioral pattern of cows exhibited differences based on the stall configuration with RMS as a proportion of the observed time (60 h). The TBI stall configuration, where the animal needs to be milked to exit the milking robot, showed a higher percentage of observed time spent in the sand bed (68%) and lying position (64%) compared with other stalls, as a proportion of the observed time (60 h). Notably, the TBII stall exhibited a significant amount as a proportion of observed time (60 h) in the holding area (16%), possibly attributed to a layout with a higher number of animals per robot, emphasizing the importance of respecting the number of animals per robot when housing in a stall with RMS. Thus, spatial configuration and the density of robotic systems are factors that influence the behavioral pattern of dairy cows.

Abstract 4250: Adherent and spheroid cell models of patient-derived xenograft for drug development and translational research

Abstract Introduction: The development of new drugs in cancer therapy comprises toxicity and efficacy tests with increasing complexity. First and foremost, in vitro experiments are performed with well-established cancer cell lines, which are subsequently validated in animal experiments as prerequisite for clinical trials. Until a few years ago, there were gaps in the complexity chain between in vitro and in vivo experiments. Ethical considerations have led to use of systems like organ on a chip or mini-organ 3D in vitro models. In cancer research, cell cultures or organoids are generated from patient tumor material. However, these cultures only reflect the tumor of one patient, which is why panels of patient tumors should be used to evaluate the effectiveness of drugs on different patients. In vivo panel screens of patient derived xenografts (PDX) mouse models need high numbers of animals and takes several months. A pre-screen with in vitro models generated from in vivo PDX tissues allows large scale and faster pre-screens complementing in vivo systems for more focused in vivo analyses. Methods: Currently we have a pool of more than 600 established PDX models of 21 tumor entities. From this pool, cancer tissues of glioblastoma, mesothelioma, gastric, head/neck, lung and breast cancer were processed in single cell suspensions and cultured under defined conditions to obtain adherent cells or spheroids. The generated PDX in vitro cultures were analyzed for cellular impurities, cancer stem cell content and perpetuation of in vivo PDX characteristics. FACS analyses for tumor specific markers, chemo sensitivity assays and growth characteristics of the PDX derived cell lines (especially for glioblastoma) were analyzed. Results: From PDX tissues used, 90% grew as adherent and/or spheroid PDX derived in vitro cultures, in which mouse cells were entirely depleted. A high percentage of these cultures showed enriched cancer stem cell features and stem cell marker expression. Tumor marker expression and standard drug sensitivity data correlate to the in vivo PDX and derived in vitro cell culture models. RNAseq data were used to predict drug sensitivities in silico for untested drugs and drug combinations on our newly established PDX derived glioblastoma cell lines. Initial screens with predicted candidates were performed. Promising conditions were successfully repeated in corresponding animal PDX models. Conclusion: The newly developed technology for establishment if in vitro cell cultures from PDX efficiently generates stably growing cell lines possessing all key features of the original PDX. These cell lines can be used for initial pre-screens to optimize and improve selection of pharmacologically active drugs or drug combinations before initiating in vivo PDX studies. Citation Format: Lars Winkler, Joshua Alcaniz, Maria Stecklum, Wolfgang Walther, Jens Hoffmann. Adherent and spheroid cell models of patient-derived xenograft for drug development and translational research [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4250.

Impact of Thermal Pretreatment on the Physicochemical Characteristics and Biomethane Yield Potential of Solid Slaughter Waste from High-Throughput Red Meat Abattoirs Valorized as a Potential Feedstock for Biogas Production

Rapid urbanization worldwide results in high demand for meat products, which in turn result in high numbers of animals being slaughtered for human consumption to meet food security demands, especially in low-income countries such as South Africa. The waste produced during slaughtering can serve as feedstock for biogas production. This study aims to determine the impacts of pasteurization and sterilization pre-treatments on high-throughput red meat abattoir solid slaughter waste’s physicochemical properties and biomethane yield when used as a feedstock for biogas production. Abattoir solid slaughter waste was collected from 45 high-throughput red meat abattoirs across South Africa and the various physicochemical properties were determined using standard methods, along with the impact of sterilization and pasteurization on red meat abattoir waste. Biomethane yield analysis was performed using AMPTS II with a hydraulic retention time of 40 days. Pasteurization and sterilization pretreatment was seen to increase physicochemical parameters such as pH, volatile solids, total solids, carbon, and nitrogen analyzed in all samples. Pasteurization and sterilization were also seen to increase biomethane yield, where methane production ranged from 610.67 Nml to 1756.30 Nml, 1592.20 Nml to 3319.30 Nml, and 949.57 Nml to 3297.87 Nml for untreated, sterilized, and pasteurized samples, respectively. There was no significant difference (p < 0.05) observed in the effect pasteurized and sterilized samples had on physicochemical properties and biomethane yield. It can be concluded that pasteurization and sterilization enhance the bioavailability of the physicochemical properties and biomethane yield of red meat solid slaughter waste when valorized as feedstock for biogas production.

Determining the In Vivo Efficacy of Plant-Based and Probiotic-Based Antibiotic Alternatives against Mixed Infection with Salmonella enterica and Escherichia coli in Domestic Chickens.

Restrictions on the use of antimicrobial compounds have led to a surge of interest in alternative solutions, such as natural, plant-based compounds. In our study, we investigated the efficacy of three feed supplements containing different additives, namely, probiotics (Lactobacillus spp., "Test substance A"), turmeric (Curcuma longa L., "Test substance B"), and fenugreek (Trigonella foenum graecum, "Test substance C"). In the experiment, we tested 180 birds of the Bábolna Tetra-SL laying hybrid breed that were infected with Salmonella enteritidis strains. The birds were randomly divided into six groups: three groups treated with the different additives, a negative control group, a positive control group, and an antibiotic-treated group using enrofloxacin. We examined the maturation and the time course of shedding of Salmonella; at the end of rearing, pathological and histopathological examinations were performed. When Salmonella was isolated from the cloacal swab samples, the enrofloxacin-treated group had a high number of animals shedding Salmonella by day 9, which was like the group treated with test material C. The greatest reduction in Salmonella shedding was observed in the groups treated with test materials A and B. In terms of pathological parameters, villus length and crypt depth were significantly better in the group treated with test material C compared to the positive and negative controls, and when comparing the body weight of the tested animals, the group treated with test material B had a significantly larger absorption surface area compared to the positive control group. Overall, the supplement with test material C proved to be the most effective. In the future, it is worthwhile to investigate the combination of the tested active substances for their possible synergistic effects and to perform a dose-response study to select the optimal dosage.

Gastrointestinal Parasites Affecting Non-Human Primates That Are Kept Ex Situ and Their Handlers in Different Brazilian Institutions: Diagnosis and Analysis of Risk Factors.

Determining gastrointestinal parasites' frequency in non-human primates (NHPs) and handlers in different Brazilian institutions, and associate it with management information. Different institutions in São Paulo (A), Brasília (B), Rio de Janeiro (C), Pará (D) and Santa Catarina (E) were included in the study. Fecal samples were processed by using coproparasitological techniques; information about NHP handling and professionals' routine were collected through the use of questionnaires. In total, 33.1% of 511 NHP samples were positive for parasites; the Entamoebidae Group and Strongyloides sp.-compatible eggs were the most detected protozoa and helminths, respectively. The Entamoebidae Group was mainly diagnosed in Alouatta from Institutions E and D, and was also the only parasite detected in handlers. Strongyloides-compatible eggs were mostly evident in fecal samples collected from Cebidae from Institutions B and D. Some risk factors associated with parasite infection were a high number of animals in the same enclosure and their use for research protocol purposes, whereas quarantine, a post-infection vacant period in enclosures and antiparasitic supply were categorized as protective factors against these agents' infection. Parasites showing different transmission routes but concomitantly circulating in NHP institutions located in different Brazilian regions were identified in the current study, with an emphasis on those presenting zoonotic potential.

Impact of the Application of Gaseous Ozone on Selected Pathogens Found in Animal Shelters and Other Facilities.

Correctly selecting disinfection procedures is crucial in facilities housing a high number of animals as it directly affects their health. The aim of this study was to verify the virucidal effect of gaseous ozone delivered by commercially available generators under controlled experimental conditions on a selection of viral pathogens (feline coronavirus, canine coronavirus, feline calicivirus, feline parvovirus) commonly found in shelters and other facilities. Two ozone generators with outputs of 3.5 g/h and 20 g/h were used to produce ozone. Virus viability after the application of ozone was evaluated by examining for typical pathogen-specific cytopathic effects on the CRFK (Crandell-Rees Feline Kidney) cell line post-incubation. No cytopathic effect was observed in feline coronavirus after the 2-h application of ozone; in canine coronavirus, the absence of a cytopathic effect was observed after the 4-h application of ozone. The absence of a cytopathic effect in feline calicivirus was observed after the 6-h application of ozone; the viability of feline parvovirus was not impaired even by the 6-h application of ozone. The results of the study confirm lower resistance to the application of gaseous ozone in enveloped viruses.

New approach methodologies to facilitate and improve the hazard assessment of non-genotoxic carcinogens-a PARC project.

Carcinogenic chemicals, or their metabolites, can be classified as genotoxic or non-genotoxic carcinogens (NGTxCs). Genotoxic compounds induce DNA damage, which can be detected by an established in vitro and in vivo battery of genotoxicity assays. For NGTxCs, DNA is not the primary target, and the possible modes of action (MoA) of NGTxCs are much more diverse than those of genotoxic compounds, and there is no specific in vitro assay for detecting NGTxCs. Therefore, the evaluation of the carcinogenic potential is still dependent on long-term studies in rodents. This 2-year bioassay, mainly applied for testing agrochemicals and pharmaceuticals, is time-consuming, costly and requires very high numbers of animals. More importantly, its relevance for human risk assessment is questionable due to the limited predictivity for human cancer risk, especially with regard to NGTxCs. Thus, there is an urgent need for a transition to new approach methodologies (NAMs), integrating human-relevant in vitro assays and in silico tools that better exploit the current knowledge of the multiple processes involved in carcinogenesis into a modern safety assessment toolbox. Here, we describe an integrative project that aims to use a variety of novel approaches to detect the carcinogenic potential of NGTxCs based on different mechanisms and pathways involved in carcinogenesis. The aim of this project is to contribute suitable assays for the safety assessment toolbox for an efficient and improved, internationally recognized hazard assessment of NGTxCs, and ultimately to contribute to reliable mechanism-based next-generation risk assessment for chemical carcinogens.

An apex predator engineers wetland food-web heterogeneity through nutrient enrichment and habitat modification.

The potential for animals to modify spatial patterns of nutrient limitation for autotrophs and habitat availability for other members of their communities is increasingly recognized. However, net trophic effects of consumers acting as ecosystem engineers remain poorly known. The American Alligator Alligator mississippiensis is an abundant predator capable of dramatic modifications of physical habitat through the creation and maintenance of pond-like basins, but its role in influencing community structure and nutrient dynamics is less appreciated. We investigated if alligators engineer differences in nutrient availability and changes to community structure by their creation of 'alligator ponds' compared to the surrounding phosphorus (P)-limited oligotrophic marsh. We used a halo sampling design of three distinct habitats extending outward from 10 active alligator ponds across a hydrological gradient in the Everglades, USA. We performed nutrient analysis on basal food-web resources and quantitative community analyses, and stoichiometric analyses on plants and animals. Our findings demonstrate that alligators act as ecosystem engineers and enhance food-web heterogeneity by increasing nutrient availability, manipulating physical structure and altering algal, plant and animal communities. Flocculent detritus, an unconsolidated layer of particulate organic matter and soil, showed strong patterns of P enrichment in ponds. Higher P availability in alligator ponds also resulted in bottom-up trophic transfer of nutrients as evidenced by higher growth rates (lower N:P) for plants and aquatic consumers. Edge habitats surrounding alligator ponds contained the most diverse communities of invertebrates and plants, but low total abundance of fishes, likely driven by high densities of emergent macrophytes. Pond communities exhibited higher abundance of fish compared to edge habitat and were dominated by compositions of small invertebrates that track high nutrient availability in the water column. Marshes contained high numbers of animals that are closely tied to periphyton mats, which were absent from other habitats. Alligator-engineered habitats are ecologically important by providing nutrient-enriched 'hotspots' in an oligotrophic system, habitat heterogeneity to marshes, and refuges for other fauna during seasonal disturbances. This work adds to growing evidence that efforts to model community dynamics should routinely consider animal-mediated bottom-up processes like ecosystem engineering.

Captive wildlife management survey in Vietnam, 2015–2021

In Vietnam, breeding and raising a wide range of wildlife species in captive wildlife facilities (CWFs) are common practices but little information on the captive wildlife population is available. We conducted surveys and developed software to create a captive wildlife facilities management (CWFM) system. This database provides up-to-date information on the distribution of CWFs, the number of species, and individuals according to the level of protection outlined by the government and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) categories. CWFs were located in all provinces and regions, but differed in distribution, number of species and individual animals. The Mekong River Delta region recorded the highest number of CWFs (35.3%) and the highest number of animals (43.1%). In 2021, 95 species belong to the highest level of protection group were being raised at 1824 CWFs; 137 species in 4554 CWFs in CITES appendix II, appendix III, government list IIB; and 139 species in 1499 CWFs belong to the common wildlife. The overall number of CWFs in 50 provinces decreased by a negative compound annual growth rate of −7.2%. However, it is crucial to continue to monitor the changing dynamics to assess the risks of disease transmission from zoonoses originating from wildlife. We recommend periodic compulsory reporting of CWF activities using the CWFM system.

Epidemiologia da mastite e interações de fatores ambientais na saúde do úbere no sistema de Compost Barn

ABSTRACT This study aimed to describe the epidemiological indexes of mastitis, milk quality and udder hygiene in the Compost Barn system, as well as to search for associations between isolated pathogens from milk with compost characteristics. Three dairy herds participated in the study, and the samples were collected during different periods on each farm. Individual milk samples were collected in duplicate for SCC analysis and microbiological culture. Environmental pathogens caused most cases of clinical mastitis on farm 2, and contagious pathogens caused the most cases on farm 1. Bed moisture was not associated with the incidence of environmental pathogens. Most of the animals remained in good udder hygiene during the study. Poor udder hygiene contributed to the increased incidence of environmental pathogens in one of the farms. A higher number of animals with a hygiene score of ≥ 2 were observed during the warmer and rainfall periods. There was no association between hygiene scores and somatic cell counts. The results suggest that pathogens isolated from milk in animals confined in Compost Barn under tropical climate are like other confinement systems adopted elsewhere. The year period influenced the udder hygiene score, reinforcing the importance of bed management throughout the year.

Differences in Weight, Hierarchy, and Incidence of Lameness between Two Groups of Adult Pigs Derived from Assisted Reproductive Technologies.

The in vitro production (IVP) and subsequent transfer of embryos (ET) to recipient mothers is not yet an established reproductive technology in the pig industry, as it is in cattle. However, that the trade of IVP-cryopreserved pig embryos is expected to start in the next decades. Society and governments are increasingly aware of the repercussions that IVP could have for animal health, welfare, behavior, or food safety, but proven scientific information for this type of animal does not exist, since no colonies of pigs have been created to this end. We created a small one and studied the differences between 16 IVP-derived pigs and 14 pigs derived from artificial insemination (AI), at 3.5 years of age, conceived from the same boar, and housed and fed under the same conditions since they were born. Incidence of lameness, position in the herd hierarchy, weight, adenosine deaminase activity, and hematological and biochemical analytes were compared between the two groups of animals. The results showed that the IVP animals weighed more, occupied higher positions in the herd hierarchy, and had a lower incidence of lameness. Although genetic differences from the maternal line could explain some of these results, it is also possible that the IVP animals developed better adaptative abilities, but more studies with a higher number of animals are necessary to reach consistent conclusions.

Bienestar felino: Mantenimiento en espacios reducidos

Currently, the cat is one of the main companion animals, and in some countries, it already surpasses the dog in this condition, and due to this high number of animals, it is sometimes kept in situations that are not always adequate for a high degree of well-being. Understanding, identifying and correcting these maintenance situations in the three main maintenance situations identified in this manuscript will significantly increase this level of well-being. Meeting the needs of the individual, under specific conditions, will increase their well-being. This animal, when kept in inadequate conditions (particularly in high numbers of animals and/or with limitations in its movement) will present behaviors indicative of stress, and the identification of such situation, as early as possible, will allow its recovery and adequacy of conditions, raising your well-being to satisfactory levels.

The spatial organization of CAFOs and its relationship to water quality in the United States

• Applied Nearest Neighbor Index and Moran’s I to quantify the spatial pattern of AFOs. • Watersheds with higher AFO NNI were associated with elevated nutrient levels. • Clustering of smaller farms (less regulated) also corresponded to high nutrients. • Results help to inform management of AFOs and other pollutant sources. Large animal operations in the United States (US) have expanded in recent decades as a solution for meeting increasing food demand. These operations can release large amounts of organic matter and nutrients into the environment, potentially impacting water quality conditions of nearby waterbodies. Often referred to as animal feeding operations (AFOs) or CAFOs (concentrated AFOs) based on nomenclature in federal regulations, these operations are usually clustered in space, which may intensify the impacts observed. However, the influence of the known spatial aggregation of CAFOs on water quality conditions has not been evaluated. This study investigates the spatial organization of CAFOs and its relationship to water quality conditions. We hypothesized that watersheds with clustered CAFOs are likely to be associated with higher concentrations of Total Phosphorus (TP) and Total Nitrogen (TN) in the US. We gathered and digitized CAFO locations in 16 US states and used TP and TN concentration data to evaluate our hypothesis. We calculated the flow-weighted mean concentration of TN and TP from 2005 to 2014 and averaged those values per season. We used the nearest neighbor index (NNI) to determine the spatial pattern (i.e., clustering or dispersed) of CAFOs per watershed and its significance level. Additionally, for states with animal number information per farm, we performed a Local Moran’s I analysis to understand if the clustering of CAFOs with a low or high number of animals relates to the TP and TN concentrations of each nearest water quality station. Overall, we found that watersheds with significant clustering patterns were associated with higher TP and TN levels. Seasonally, this finding also held principally during spring and summer seasons, when manure tends to be land applied. Our Local Moran’s I analysis also revealed that the clustering of smaller and medium-sized farms, usually less regulated, is associated with elevated TP and TN concentrations. This reveals that the small, yet potentially unregulated farms could be highly impactful to the environment, which warrants further study. Given the lack of information on the influence of CAFO clustering (and other pollutant source clustering) on water quality and that most states do not regulate emitters based on this aspect, our outcomes advance the knowledge of how these entities may be driving changes to the environment. This study also brings insights into new water quality modeling approaches and supports future policy decisions.

Looking beyond the Shoal: Fish Welfare as an Individual Attribute.

Simple SummaryThe fish farming industry is characterized by settings where large numbers of fishes are raised together at high stocking densities, effectively obliterating the individual. Given that animal welfare is an individual attribute that refers to how an animal experiences her world, it follows that ensuring good welfare for the different individuals is difficult in fish farms. In this paper we review evidence supporting the notion that fishes are individuals and fish welfare should thus also be considered at the individual level, examine the ways that animal welfare is assessed in fish farms, evaluate these practices in light of individualized terrestrial animal welfare assessment methods, and make recommendations regarding research that could lead to a better understanding of how to provide each individual fish with good welfare in captivity.Welfare is an individual attribute. In general, providing captive nonhuman animals with conditions conducive to good welfare is an idea more easily applied when dealing with few individuals. However, this becomes much harder—if not impossible—under farming conditions that may imply high numbers of animals living in large group sizes. Although this is a problem inherent to intensive animal farming, it is possibly best exemplified in fish farming, for these practices often rely on extremely high numbers. In this paper we review evidence supporting the notion that fishes are individuals and fish welfare should thus also be considered at the individual level, examine the current state of welfare assessment in the aquaculture industry, evaluate these practices in light of individualized terrestrial animal welfare assessment methods, and make recommendations regarding research that could lead to a better understanding of how to provide each individual fish with good welfare in captivity.

A New Sampling Approach for the Detection of Swine Influenza a Virus on European Sow Farms.

Simple SummaryDue to concerns in public health and its negative impact on the pig industry the need for Influenza A virus (IAV) surveillance is rising. The gold standard procedure for detecting IAV is to sample acutely diseased pigs. Endemic infections with unspecific clinical signs and low disease prevalence need new approaches. Our study aimed to evaluate a standardized sampling procedure for the detection of IAV in epidemically and endemically infected farms. We performed a cross-sectional study in 131 farms investigating three different age groups per farm in 12 European countries. The results of our investigation indicate that 10 nasal swabs each in suckling piglets, weaners and middle of nursery is a valuable tool for influenza detection and identification of subtypes. However, for farms with a lower prevalence than 15% it is advisable to either increase the number of nasal swabs in each age group or to use group sampling methods. Interestingly, different subtypes were found in different age groups. Thus, our study underlines that sampling of different age groups is mandatory to obtain a comprehensive overview on all circulating variants on farm. In addition, our results highlight that sampling strategies should also consider piglets without obvious clinical signs for IAV infection.Swine influenza A virus (swIAV), which plays a major role in the porcine respiratory disease complex (PRDC), is eliminated from the respiratory tract within 7–9 days after infection. Therefore, diagnosis is complicated in endemically infected swine herds presenting no obvious clinical signs. This study aimed to investigate the right time point for sampling to detect swIAV. A cross-sectional study was performed in 131 farms from 12 European countries. The sampling protocol included suckling piglets, weaners, and nursery pigs. In each age group, 10 nasal swabs were collected and further examined in pools of 5 for swIAV by Matrix rRT-PCR, followed by a multiplex RT-PCR to determine the influenza subtype. SwIAV was detected in 284 (37.9%) of the samples and on 103 (78.6%) farms. Despite the highest number of animals with clinical signs being found in the nursery, the weaners were significantly more often virus-positive compared to nursery pigs (p = 0.048). Overall, the swIAV detection rate did not significantly differ between diseased or non-diseased suckling and nursery piglets, respectively; however, diseased weaners had significantly more positive pools than the non-diseased animals. Interestingly, in 9 farms, different subtypes were detected in different age groups. Our findings indicate that to detect all circulating swIAV subtypes on a farm, different age groups should be sampled. Additionally, the sampling strategy should also aim to include non-diseased animals, especially in the suckling period.

A Smart Camera Trap for Detection of Endotherms and Ectotherms

Current camera traps use passive infrared triggers; therefore, they only capture images when animals have a substantially different surface body temperature than the background. Endothermic animals, such as mammals and birds, provide adequate temperature contrast to trigger cameras, while ectothermic animals, such as amphibians, reptiles, and invertebrates, do not. Therefore, a camera trap that is capable of monitoring ectotherms can expand the capacity of ecological research on ectothermic animals. This study presents the design, development, and evaluation of a solar-powered and artificial-intelligence-assisted camera trap system with the ability to monitor both endothermic and ectothermic animals. The system is developed using a central processing unit, integrated graphics processing unit, camera, infrared light, flash drive, printed circuit board, solar panel, battery, microphone, GPS receiver, temperature/humidity sensor, light sensor, and other customized circuitry. It continuously monitors image frames using a motion detection algorithm and commences recording when a moving animal is detected during the day or night. Field trials demonstrate that this system successfully recorded a high number of animals. Lab testing using artificially generated motion demonstrated that the system successfully recorded within video frames at a high accuracy of 0.99, providing an optimized peak power consumption of 5.208 W. No water or dust entered the cases during field trials. A total of 27 cameras saved 85,870 video segments during field trials, of which 423 video segments successfully recorded ectothermic animals (reptiles, amphibians, and arthropods). This newly developed camera trap will benefit wildlife biologists, as it successfully monitors both endothermic and ectothermic animals.

Effect of Pre-partum Supplementation of Vitamin E and Selenium on Post-partum Reproductive and Productive Performance in Dairy Cows

Background: The study was planned to determine the effect of oral supplementation of vitamin E and Selenium on productive and reproductive performance in 40 Jersey cows and consequent effect on the growth of their progeny (calves). Methods: The experimental animals were divided into two homogenous groups (A and B). Animals in group A were given Vitamin E (200 mg) and Selenium (10 mg) daily orally; 250 days onwards prepartum for 21 days. The cows belonging to the group B were not provided these supplements and served as untreated control group. Result: Group A animals took significantly (P less than 0.01) less (2/3) time than those included in Group B for expulsion of the placenta. Additionally, lesser number of cows in Group A than those in Group B suffered from retention of placenta (ROP) indicating improvement of reproductive performance in the group with no significant effect on growth of calves and milk yield in the two groups. Therefore, from the experiment, it was concluded that supplementation of Vitamin E and Selenium to dairy cows during last month of pregnancy decreases time of placenta expulsion with no significant effect on the growth of their progeny (calves). The present study also concludes that higher number of animals may be taken for the experiment for a good dairy managemental programme.

Utility of the Intradermal Skin Test in a Test-and-Cull Approach to Control Bovine Tuberculosis: A Pilot Study in Ethiopia.

Bovine tuberculosis (bTB) is one of the top three, high-priority, livestock diseases in Ethiopia and hence, the need for evaluation of potential control strategies is critical. Here, we applied the test-and-segregate followed by cull strategy for the control of bTB in the intensive Alage dairy farm in Ethiopia. All cattle reared on this farm were repeatedly skin tested using the Comparative Cervical Tuberculin (CCT) test for a total of five times between 2015 and 2021. During the first (October 2015) and second (March 2017) rounds of testing, all reactor animals (>4 mm) were culled, while those that were deemed as inconclusive (1–4 mm) were segregated and retested. At retest, animals with CCT >2 mm were removed from the herd. In the third (December 2017) and fourth (June 2018) rounds of tuberculin testing, a more stringent approach was taken wherein all reactors per the severe mode of CCT test interpretation (>2 mm) were culled. A final herd status check was performed in May 2021. In summary, the number of CCT positives (>4 mm) in the farm dropped from 23.1% (31/134) in October 2015 to 0% in December 2017 and remained 0% until May 2021. In contrast, the number of Single Cervical Tuberculin (SCT) test positives (≥4 mm) increased from 1.8 to 9.5% (from 2017 to 2021), indicating that CCT test might not be sufficient to effectively clear the herd of bTB. However, a more stringent approach would result in a drastic increase in the number of false positives. The total cost of the bTB control effort in this farm holding 134–200 cattle at any given time was conservatively estimated to be ~US$48,000. This, together with the need for culling an unacceptably high number of animals based on skin test status, makes the test-and-cull strategy impractical for nationwide implementation in Ethiopia and other low- and middle-income countries (LMICs) where the infection is endemic. Hence, there is an increased emphasis on the need to explore alternate, affordable measures such as vaccination alongside accurate diagnostics to help control bTB in endemic settings.

Quantification of methane emissions from cattle farms, using the tracer gas dispersion method

In Denmark, agriculture is the largest source of anthropogenic methane emissions (81%), mainly from cattle (dairy and beef) farms. Whole-farm methane emissions were quantified at nine Danish cattle farms, using the tracer gas dispersion method. Five to six measurement campaigns were carried out at each farm, covering a full year. Of the nine cattle farms, seven were home to dairy cows and two to beef cattle. The farms represented typical breeds, housing and management systems used in Denmark. Whole-farm methane emission rates ranged from 0.7 to 28 kg h−1, with the highest measurements seen at locations with the highest number of animals. Emissions tended to be higher from August to October, due to elevated temperatures and high amounts of stored manure during this period of the year. The average emission factor (EF) for dairy cow farms was 26 ± 8.5 g Livestock Unit (LU)−1 h−1, whereas it was 16 ± 4.1 LU−1 h−1 for beef cattle farms, i.e. 38% lower for the latter. The use of deep litter house management explained some of the differences found in the EFs for dairy cows. Methane emission rates estimated using IPCC models and national guidelines tended, on average for all farms and measurements, to be underestimated by 35% in comparison with the measured methane emissions, for all models and farms. The results suggest that future improvements to inventory models should focus on enteric methane emissions from beef cattle and manure methane emissions for both dairy cows and beef cattle, especially from deep litter management.