Energy and exergy studies on the receiver models with materials and heat transfer fluids.

This work focuses on meeting the growing demand in solar energy conversion for small-scale applications. In this regard, experimental and CFD research has been done to examine the thermal performance (energy and exergy efficiencies) of a dish collector (reflector and receiver) system with different receiver models. In this work, receivers with uniform absorber cavity areas having cylindrical and hemispherical shapes were modeled for length-to-diameter ratios (L/D) of 1.5, 1, and 0.75. The modeled receivers having coil tube configurations concerning the geometrical shape of the models were tested with two different materials of aluminum and copper. The performance of the receiver models was compared by experimental and CFD methods for the average solar direct normal irradiations of 860 W/m2 by the dish reflector area of almost 12 m2. The supplied average heat flux by the dish reflector was 7 kW/m2 at the absorbing area of the cavity receivers. The energy and exergy efficiencies from the experimental and CFD analyses on the models were determined based on the cavity surface temperature distribution of receiver walls, and heat gain for different mass flow rates by the heat transfer fluid water. The receiver with copper material and L/D ratio of 0.75 has been found as the optimized one among all other models with the maximum obtained energy and exergy efficiencies of 73.64 and 7.31% when water is used as the heat transfer fluid. The performance of the optimized receiver model was also validated with a few other heat transfer fluids such as SiC + water nanofluid and therminol VP1.

Seasonal, physiological and bacteriological risk factors for subclinical mastitis in dairy cows maintained under different farming conditions.

Subclinical mastitis (SCM) is a major health problem of dairy animals in India and across the globe. An identification of potential risk factors of SCM can help for efficient udder health management in dairy animals. In this study, apparently healthy cows (HF crossbred: n = 45; Deoni: n = 43) were screened for SCM during different seasons through milk somatic cell count (SCC: reference test using 200 × 103 cells/ml as cut off value), California mastitis test (CMT) and differential electrical conductivity (DEC) test at an organized research farm. SCM positive milk samples (n = 34) were inoculated in selective media for Coliform sp., Streptococcus sp. and Staphylococcus sp. and DNA was isolated (n = 10) for species confirmation by 16s rRNA method. Both bivariate and multivariate models were used for risk assessment. We found the cumulative prevalence of 31 and 65% SCM in Deoni and crossbred cows, respectively. Screening of 328 crossbred cows under field conditions revealed point prevalence of 55% SCM. Multivariate analysis revealed stage of lactation (SOL), milk yield in previous lactation and test day milk yield in Deoni cows, as well as parity and mastitis treatment history in current lactation in HF crossbred cows as risk factors. SOL was a significant factor under field conditions. Receiver operated characteristic curve analysis revealed better accuracy of CMT than DEC. We found more mixed infections due to Staphylococcus sp. and Streptococcus sp. in culture, while 16s rRNA based molecular method revealed lesser-known pathogens associated with SCM. It is concluded that SCM prevalence rate is higher in crossbred than indigenous cows and these breeds have different risk factors for SCM. HF crossbred cows had similar SCM prevalence rate under different farming conditions, where CMT can be used for SCM diagnosis with excellent accuracy. The 16s rRNA method is useful for specific identification of lesser known and emerging mastitis pathogens.

Recent advancements in flat plate solar collector using phase change materials and nanofluid: a review.

Solar energy has emerged as one of the most promising sources of renewable energy to replace the current energy market. Flat plate solar collectors (FPSC) not only are one of the easiest collectors to produce and work with but also are cheap and economical. Due to this, extensive research has been done on FPSC to improve its efficiency and reliability. Some of the methods include using nanofluids to improve the heat transfer process, phase change materials to increase and maintain stable temperatures, or integrating the collector with additional components. This review article focuses on analyzing the recent improvements in FPSC, with a particular emphasis on the achieved efficiencies and temperatures in the studies. Additionally, it is aimed at updating the information in the current field, providing a comprehensive overview of the advancements in FPSC technology. Furthermore, the article explores the combined effects of nanofluids and phase change materials in photovoltaic/thermal (PVT) collectors, considering the resulting temperature enhancements. By critically evaluating the efficiency improvements and temperatures achieved through these approaches, this article is aimed at providing valuable insights into the state-of-the-art of FPSC and their potential for advancing solar energy utilization.

Relationship among seminal antigenicity, antioxidant status and metabolically active sperm from Holstein-Friesian (Bos taurus) bulls.

Sperm antigenicity has been implicated as a regulatory factor for acquiring fertilizing competence in the female reproductive tract. Overt immune response against the sperm proteins leads to idiopathic infertility. Hence, the aim of the study was to evaluate the influence of the auto-antigenic potential of sperm on the antioxidant status, metabolic activities and reactive oxygen species (ROS) in bovine. Semen from Holstein-Friesian bulls (n = 15) was collected and classified into higher (HA, n = 8) and lower (LA, n = 7) antigenic groups based on micro-titer agglutination assay. The neat semen was subjected to the evaluation of bacterial load, leukocyte count, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and lipid peroxidation (LPO) levels. Antioxidant activities in seminal plasma and intracellular ROS levels in the post-thawed sperm were estimated. The number of leukocytes was lower (p < .05) in the HA than the LA semen. The percentage of metabolically active sperm was higher (p < .05) in HA than the LA group. The activities of total non-enzymatic antioxidant, superoxide dismutase (SOD) and catalase (CAT) were higher (p < .05) while glutathione peroxidase activity was lower (p < .05) in the seminal plasma of LA group. The LPO levels of neat sperm and the percentage sperm positive for intracellular ROS in the cryopreserved sample were lower (p < .05) in the HA group. Auto-antigenic levels were positively correlated with the percentage of metabolically active sperm (r = 0.73, p < .01). However, the seminal auto-antigenicity was negatively (p < .05) correlated with the levels of SOD (r=-0.66), CAT (r=-0.72), LPO (r=-0.602) and intracellular ROS (r=-0.835). The findings were represented in graphical abstract. It is inferred that the higher auto-antigenic levels protect the quality of bovine semen by promoting sperm metabolism and lowering ROS and LPO levels.

Production and Evaluation of Encapsulated Zinc Oxide on Performance, Ileal Digestibility and Zinc Transporter Gene Expression in Broiler Chicken.

The present study was undertaken for the production of encapsulated zinc and its evaluation in broiler chicken diet. The process of microencapsulation involved the use of polymers, gum arabic and maltodextrin with a maximum encapsulation of efficiency of 66%. Encapsulated material contained about 20% zinc oxide (ZnO) as core material following the freeze-drying process. One hundred and ninety-two-day-old broiler chicks were distributed in four groups in six replications having eight birds in each. The four groups comprised control (inorganic source of zinc), En-Zn-100 (encapsulated zinc at 100% of control), En-Zn-50 (encapsulated zinc at 50% of control), and Org-Zn-50 (Zn-methionine at 50% of control). The experiment was carried out for 35 days following standard management practices. The live weight gain, feed intake and FCR were comparable among groups. Plasma and muscle zinc (ppm) content was unaffected by the level or source of zinc supplementation. The zinc apparent ileal digestibility coefficient was significantly (P < 0.05) higher in En-Zn-50 fed groups, while crude protein digestibility was not affected by the level or form of Zn supplementation. Bone weight, length, and zinc content were comparable, and bone ash content was significantly different among the groups. Relative expression of ZnT2 was significantly upregulated in encapsulated zinc-fed groups. From the study, it could be concluded that supplementation of zinc either as encapsulated or organic form at 50% of inorganic source (ZnO) could be sufficient to maintain the growth performance, serum, tissue and bone mineral content in broiler chicken.

Application of encapsulated nano materials as feed additive in livestock and poultry: a review.

Livestock plays a significant role in the socio-economic development of developing countries by providing livelihood and nutritional security, transport, contingency during crop failure and day-to-day earning to the farm family. The human population is projected to reach 9.9 billion by 2050, which along with increasing urbanization and growing income is expected to increase the demand for livestock products. Global livestock feed demand will be almost doubled, and 1.3 billion tons of grain will be required for feeding farm animals alone. To increase the livestock production efficiency, feed additives have been used to improve the production and growth of high-quality livestock products. Even though feed additives have a pertinent role in animal growth performance, disadvantages like endo toxin production and reduced absorption of nutrients by interaction of additives with naturally occurring nutrients limits the use of feed additives. A majority of the macronutrients in the rumen are metabolized or transformed by microbes, hence nutrients should be preserved and made available in the small intestine. Encapsulation technology, which has been employed in a broad range of applications in various fields of science, can address this challenge and rejuvenate livestock nutrition research. The present review explores the importance of encapsulated nano material in livestock and poultry production.

Antimicrobials use and their indications in dairy farm and individual farmer production conditions in southern India.

Antimicrobials use (AMU) is the key driver for development of antimicrobials resistant (AMR) pathogen in human and veterinary medicines. Therefore, understanding AMU pattern is prerequisite for focused intervention on AMR. The aim of this study was to understand the AMU pattern and their indications in dairy farm and individual farmer production conditions in southern India. Treatment registers of 6 years (2012 to 2017) containing 3178 cases from dairy farm and 12,057 cases during 2017-2019 under individual farmer production conditions were collected and analyzed by log-linear model. Seasons were classified as rainy (Jul-Oct), winter (Nov-Feb), and summer (Mar-June) as per climatic conditions in the study area. It is observed that mastitis, lameness, and reproductive problems were major health disorders among treated animals in farm and individual farmer production conditions. Season had significant influence on proportional rates of various health disorders in crossbred cows under both the production conditions. AMU pattern was different between the breeds and production conditions. Antibiotics were the most commonly used group of drugs (23-28%) than non-steroidal anti-inflammatory drugs (20%), antihistamine (17%), and nutrient supplements (14-16%). Antibiotics were mostly used for mastitis (47-67%) than other conditions like fever (18%), reproductive problems (15%), and lameness (16%). For treating mastitis, cephalosporins and gentamicin were most commonly used under individual farmer production condition, while penicillin group was frequently used in farm. It is concluded that mastitis is the most common indication for AMU in dairy animals and thus developing appropriate guidelines for mastitis treatment and control is necessary to reduce overall AMU.

Supraphysiological concentration of urea affects the functional competence of Holstein-Friesian (Bos taurus) sperm.

To understand the effects of urea on sperm functional attributes, fresh bull semen (n = 12) was subjected to four different concentrations (mg/mL) of urea to mimic the physiological (0.04 and 0.13), supraphysiological (0.43) concentrations and control (0 mg/mL). Sperm membrane integrity, kinematics, chromatin integrity, and mitochondrial membrane potential were assessed at different time points (before incubation, 0, 1, 2, and 4 h) of incubation. The concentration of urea in serum and seminal plasma was estimated and correlated with the ejaculate rejection rate and sperm functional attributes. The relative expression of urea transporter gene transcripts (UT-A and UT-B) was assessed in sperm and testis (control) using real-time PCR. The supraphysiological concentration of urea affected sperm kinematics, viability, functional membrane integrity, and acrosome integrity within 1 h of incubation (p < 0.05). Sperm head area decreased (p < 0.05) at 0 h and subsequently increased at 1 h of incubation in all media except supraphysiological (0.43 mg/dL) concentration of urea. Seminal plasma urea concentration showed a significant negative correlation with sperm motility, membrane integrity, and mitochondrial membrane potential (p < 0.05), but had a positive correlation with the ejaculate rejection rate (r = 0.69). Relative expression of the urea transporter genes revealed that UT-A was expressed only in the testis. In contrast, UT-B was expressed in both the testis and sperm, suggesting UT-B's role in regulating urea transport in sperm. At a supraphysiological level, urea adversely affected sperm functional attributes, osmoadaptation and may affect fertility.

Sperm phenotypic characteristics and oviduct binding ability are altered in breeding bulls with high sperm DNA fragmentation index.

In the present study, we standardized an in vitro oviduct explants model for cattle and assessed the oviduct explants binding ability and phenotypic characteristics of spermatozoa obtained from breeding bulls with high- and low-sperm DNA fragmentation index (DFI%). Cryopreserved spermatozoa from Holstein Friesian crossbred breeding bulls (n = 45) with known field fertility were assessed for DFI% and were classified into either high DFI% or low DFI% category. Flow cytometry was used to assess sperm membrane integrity, acrosome reaction status, mitochondrial membrane potential and intracellular calcium concentrations. It was found that spermatozoa from bulls with low DFI% had significantly higher (P < 0.05) membrane integrity, acrosome intactness, and mitochondrial membrane potential. To assess the sperm oviduct binding ability, oviduct explants were prepared by incubating the oviduct cells overnight in TCM-199 medium at 38.5 °C under 5% CO2. Different sperm concentrations and times of incubation were evaluated and found that 2 million spermatozoa and 1-h incubation yielded high binding index (BI). The BI was also significantly (P < 0.01) higher (>2 times) in the bulls with low-DFI% as compared to high DFI% bulls. The correlation between binding index and DFI% was negative and significant (r = -0.528; P < 0.05). Further, the binding index was positively correlated with conception rate (r = 0.703), intact sperm membrane (r = 0.631) and mitochondrial membrane potential (r = 0.609). It is inferred that sperm phenotypic characteristics and oviduct binding ability are impaired in breeding bulls with high sperm DFI%, which might be associated with low conception rates in these bulls.

Nano zinc supplementation in goat (Capra hircus) ration improves immunity, serum zinc profile and IGF-1 hormones without affecting thyroid hormones.

The trial was aimed at evaluating probable superiority, if any of nano zinc (NZn) over inorganic zinc (Zn) on immunity, serum minerals and T3 , T4 , and IGF-1 hormone profiles in goats. NZn was synthesized by using 0.45 M aqueous solution of Zn nitrate and 0.9 M aqueous solution of sodium hydroxide (average particle size 74 nm). Twenty-four male goats were grouped into four groups as per their body weight and were supplemented with either a basal diet with concentrate and straw at 50:50 ratio (Negative control, NC) alone or supplemented with 50 mg/kg Zn (Control) from inorganic Zn source, that is ZnO (IZn-50), 50 mg/kg Zn from NZn (NZn-50) or 25 mg/kg Zn from NZn (NZn-25). No change was observed in thyroid hormone status on zero and 90th day of experimental feeding, but NZn supplementation improved (p < 0.05) IGF-1 level on 90th day serum samples. Zn supplementation improved the humoral immunity in all the groups irrespective of the source. Similarly, cell-mediated immunity (CMI) measured by skinfold thickness after injecting Con-A, was also improved in Zn supplemented groups than control at 6, 12 and 48 h of incubation. NZn-50 animals showed highest HI (haemagglutination inhibition) titre as well as skin thickness. The CD 4 + (cluster of differentiation in %) was more (p < 0.05) in Zn supplemented groups. NZn-50 showed higher (p < 0.05) CD 8 + count than NC and similar (p > 0.05) to IZn-50 and NZn-25 groups without affecting (p > 0.05) the ratio of CD 4 + , CD 8 + among the treatment groups. Thus, NZn supplementation at 25 mg/kg had similar immunity and serum T3 , T4 and IGF-1 profiles compared with IZn at 50 mg/kg dose.

Effect of Supplementation of Nano Zinc Oxide on Nutrient Retention, Organ and Serum Minerals Profile, and Hepatic Metallothionein Gene Expression in Wister Albino Rats.

A study was conducted to validate the effects of nano form of zinc (NZn) on nutrient digestibility, zinc retention, organ and serum zinc profile, and hepatic metallothionein gene expression in Wistar albino rats (WAR). Nano zinc (NZn) was synthesized through chemical method, by using 0.45 M zinc nitrate [Zn(NO3)2.6H2O] and 0.9 M sodium hydroxide (NaOH). The NZn particle in its oxide form was characterized by TEM-EDAX and XRD, and found to be in nano range (below 100 nm. Zinc was supplemented to the Wistar albino rats (WAR) through synthetic semi-purified diet either without Zn, or as inorganic zinc (IZn; 25 mg/kg), or as synthesized NZn (25, 12.5, 6.25, 3.125 or 50 mg/kg DM) for 60 days. The zinc content was observed to be significantly (P < 0.05) higher in liver, bone, kidney, and serum due to NZn supplementation where NZn-50 had highest zinc content and control had the least, without affecting Fe, Mn, and Cu. NZn at 12.5 mg/kg group rats were either comparable or better than IZn at 25 mg/kg in terms of zinc retention, CP digestibility, zinc level in serum, liver, bone, and kidney suggesting its better bioavailability simultaneously also reduced fecal excretion of zinc to the environment. Metallothionein mRNA expression was upregulated in NZn at 25 mg/kg and NZn at 50 mg/kg than IZn at 50 mg/kg. Thus, in WAR, NZn at half of the ICAR recommendation (25 mg/kg DM) is as effective as inorganic zinc at 100% of recommended dose.

Nano zinc, an alternative to conventional zinc as animal feed supplement: A review.

The uniqueness of Zn is that, it is the second most abundant trace element in the animal body but can't be stored in the body, thus regular dietary intake is required. Zinc oxide (ZnO) nanoparticles (NP) particles are being extensively used in paints, skin lotions pigments, food, electronics appliances, biological and pharmaceutical applications and many more. Zinc oxide nanoparticles are the specially prepared mineral salt having particle size of 1 to 100 nm. It promotes growth can act as antibacterial agent, modulates the immunity and reproduction of the animals. Both in lower and higher doses of specifications it has exhibited a variety of effects on animal performances. Apart from being highly bio-available, reports have already pointed out the growth promoting, antibacterial, immuno-modulatory and many more effects of nano zinc (nZn). These can be used at lower doses and can provide better result than the conventional Zn sources and indirectly prevents environmental contamination also. The toxicological studies provide mixed results in animal models. Studies been undertaken in diversified animal species and encouraging effects have been reported with nZn supplementation. However, there is a need to optimize the dose and duration of ZnO NP supplementation for human and livestock, depending on its biological effects. Actual bioavailability of ZnO NP in livestock is still to be worked out. In this review we have attempted to summarize, conclude the beneficial effects of nZnO and its possible usage as mineral supplement to different categories of human and livestock.

Relationship between seminal plasma tuberoinfundibular peptide of 39 residues and sperm functional attributes in buffalo (Bubalus bubalis).

The buffalo seminal plasma protein profile and its relationship with sperm quality have not been studied in detail. Thus, the aim of the present study was to profile buffalo seminal plasma proteins and to assess the relationship between differentially expressed proteins and sperm characteristics. Semen samples (n = 44) were collected from 11 Murrah buffalo bulls (four ejaculates from each animal) and seminal plasma protein profiling was performed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Matrix-assisted laser desorption ionisation time-of-flight analysis of one of the differentially expressed proteins, namely the 11-12 kDa protein, identified it as tuberoinfundibular peptide of 39 residues (TIP39). Western blot analysis confirmed the presence of TIP39, with TIP39 expression in seminal plasma varying among bulls. Based on TIP39 levels, bulls were classified into two groups, those with high and low protein. The percentages of spermatozoa positive for mitochondrial membrane potential test, chromatin distribution test, synthetic media sperm penetrability test and acrosomal integrity test were significantly (P < 0.05) high in the high protein group. The present study is the first to demonstrate the presence of TIP39 in buffalo seminal plasma and the positive effect of TIP39 on the functional parameters and fertilising ability of spermatozoa.