Genetic and non-genetic factors affecting semen production and quality characteristics of Gir cattle breed under semi-arid climate

Research (Published online: 27-08-2020)

32. Genetic and non-genetic factors affecting semen production and quality characteristics of Gir cattle breed under semi-arid climate

K. G. Bhave, K. Thilak Pon Jawahar, P. Kumarasamy, T. Sivakumar, C. Joseph, T. Shirsath, P. Deshmukh and R. Venkataramanan

Veterinary World, 13(8): 1714-1718

ABSTRACT

Aim: This study aims to evaluate genetic and non-genetic factors influencing semen production potential of Gir bulls.

Materials and Methods: Data on semen quantity (n=6911) and quality (n=466) available from January 2011 to December 2018 at BAIF's frozen semen station, Jind, Haryana, India, were utilized for the study. Factors, namely, season of collection, age at collection, and bull (random effect) were studied for their effect on quantitative and qualitative semen traits. Least square means for the traits were obtained using a general linear model. The effect of age within bull for repeatable traits was analyzed using a longitudinal model with age as the control variable. Multivariate analysis using mixed repeatability model equation was utilized to estimate bull effect correlation (genetic + permanent environmental correlation), phenotypic correlations, and repeatability.

Results: The overall least square means of ejaculate volume, sperm concentration, total sperms, initial and post-thaw motility, hypo-osmotic swelling test, and acrosome integrity of frozen semen were 6.62±0.03 ml, 1.22±0.01 109/ml, 8.09±0.05 109/ml ejaculate, 75.78±0.001%, 55.92±0.0001%, 55.13±0.005%, and 71.08±0.001%, respectively. The season of the collection showed a significant effect on volume, concentration, total sperm, and initial motility. The performance of bulls was superior in summer season, followed by winter and monsoon. Increase in semen attributes during summer season was due to the effect of lower temperature on sensitive stages of spermatogenesis. Age at collection had a significant effect on all semen traits. Volume and total sperm count showed increasing trend while concentration showed a decreasing trend with an increase in age. Motility and quality traits did not show any particular pattern. Individual bulls showed differences in all the semen performance traits with age. The repeatability of the traits ranged from 0.04 (HOST) to 0.58 (acrosome integrity). Bull effect correlation ranged from –0.73 (initial motility and acrosome integrity) to 0.93 (HOST and acrosome integrity).

Conclusion: Individual bulls showed variation in traits measured over age. The result of the study could be utilized in suggesting suitable management plans to achieve the desired profit by improving semen quality in Gir bulls.

Keywords: Gir, longitudinal analysis, repeatability, bull effect, and semen production.

Relationship between somatic cell counts and subclinical mastitis in lactating dairy cows

Research (Published online: 27-08-2020)

31. Relationship between somatic cell counts and subclinical mastitis in lactating dairy cows

S. M. Mostafizur Rahaman Sumon, Mst. Sonia Parvin, Md. Amimul Ehsan and Md. Taohidul Islam

Veterinary World, 13(8): 1709-1713

ABSTRACT

Background and Aim: Subclinical mastitis (SCM) is one of the most prevalent diseases of dairy cows, and somatic cell count (SCC) is widely used to determine SCM and milk quality. However, setting the threshold of SCC is very important. This study aimed to determine the cow-level threshold of SCC to differentiate milk of SCM affected cows from normal milk in Bangladesh.

Materials and Methods: Sensitivity (Se) and specificity (Sp) along with other characteristics of different thresholds of SCC were determined considering the bacterial culture as the gold standard test. Three definitions of intramammary infection (IMI) were set based on the group of pathogens involved. Five categories of SCC thresholds were considered for analysis.

Results: Se and Sp of thresholds of SCC greatly varied as definitions of IMI changed. Irrespective of SCC thresholds, Se increased when isolation of major pathogens included in IMI definitions. Se decreased when SCC thresholds increased (from 100 to 300 × 103 cells/mL) for all IMI definitions and ranged from 60.6% to 20.3%. The highest Se was found at low SCC threshold (100 × 103 cells/mL), which resulted in less false-negative outcome. On the other hand, Sp increased with the increment of SCC thresholds giving rise to a less false-positive outcome.

Conclusion: The cow-level SCC threshold of 100 × 103 cells/mL was found appropriate to identify subclinical IMI of dairy cows.

Keywords: Bangladesh, bovine mastitis, intramammary infection, somatic cell count threshold, sensitivity, specificity.

Unique patterns of cardiogenic and fibrotic gene expression in rat cardiac fibroblasts

Research (Published online: 26-08-2020)

30. Unique patterns of cardiogenic and fibrotic gene expression in rat cardiac fibroblasts

Kittipong Tachampa and Tuempong Wongtawan

Veterinary World, 13(8): 1697-1708

ABSTRACT

Background and Aim: Cardiac fibroblasts are important for both normal and pathological states of the heart, but the knowledge in cell physiology and genomics is still poorly understood. The aims of the present study were; first, to investigate the expression of cardiac and fibrotic genes in rat cardiac fibroblasts compared to cardiomyocytes and other fibroblasts (skin and muscle fibroblasts), second, to examine the in vitro effect of serum concentration on fibroblast gene expression. The findings can potentially be applied in ischemia/reperfusion models.

Materials and Methods: Rat cardiac fibroblasts were collected and cultured in different conditions, and their gene expression (21 cardiogenic genes and 16 fibrotic genes) was compared with cardiomyocytes and other fibroblasts using comparative quantitative polymerase chain reaction. We also mimicked myocardial ischemia/reperfusion by depleting and then adding a serum into the culture in conventional culture (10% serum).

Results: Cardiac fibroblasts expressed most of the cardiogenic genes, but their expression levels were significantly lower than in cardiomyocytes, while almost all fibrotic genes in the cardiac fibroblasts were significantly more highly expressed than in cardiomyocytes, except matrix metallopeptidase 9 (Mmp9) which also had greater expression in other fibroblasts. After mimicking cardiac ischemia and reperfusion in vitro by starving and then adding a serum into the cardiac fibroblast culture, the results revealed that Mmp9 expression was significantly increased (>30 times) after increasing but not reducing the serum in the culture. The expression of most cardiogenic and fibrotic genes in cardiac fibroblasts tended to decrease after increasing the serum in the culture. These changes were specific to cardiac fibroblasts but no other fibroblasts.

Conclusion: Cardiac fibroblasts have a distinct pattern of gene expression from other fibroblasts and cardiomyocytes. They are also sensitive to high serum concentration but not affected by serum depletion, suggesting that the process of developing cardiac fibrosis might be stimulated by reperfusion or overcirculation rather than ischemia. The cell starvation followed the adding of serum may serve as a useful model to study cardiac fibrosis cause by the change of blood flow.

Keywords: cardiac fibroblasts, cardiomyocytes, gene expression, in vitro model, ischemia, reperfusion.

Applications, challenges, and strategies in the use of nanoparticles as feed additives in equine nutrition

Review (Published online: 26-08-2020)

29. Applications, challenges, and strategies in the use of nanoparticles as feed additives in equine nutrition

P. Ravi Kanth Reddy, Duvvuru Yasaswini, P. Pandu Ranga Reddy, Mohamed Zeineldin, M. J. Adegbeye and Iqbal Hyder

Veterinary World, 13(8): 1685-1696

ABSTRACT

The rapid expansion of nanotechnology has been transforming the food industry by increasing market share and expenditure. Although nanotechnology offers promising benefits as feed additives, their usage in equines is primarily geared toward immunotherapy, hyper-immunization techniques, drug delivery systems, grooming activities, and therapeutic purposes. Nanoparticles could be engaged as alternatives for antibiotic feed additives to prevent foal diarrhea. Gold nanoparticles are proved to provide beneficial effects for racehorses by healing joint and tendon injuries. Because of the poor bioavailability of micro-sized mineral salts, the usage of nano-minerals is highly encourageable to improve the performance of racehorses. Nano-Vitamin E and enzyme CoQ10 for equines are no longer a simple research topic because of the increased commercial availability. Employing nanotechnology-based preservatives may offer a promising alternative to other conventional preservatives in preserving the quality of equine feed items, even during an extended storage period. While nanoparticles as feed additives may provide multitudinous benefits on equines, they could elicit allergic or toxic responses in case of improper synthesis aids or inappropriate dosages. The safety of nano-feed additives remains uninvestigated and necessitates the additional risk assessment, especially during their usage for a prolonged period. To adopt nano-feed additives in horses, there is an extreme paucity of information regarding the validity of various levels or forms of nanoparticles. Further, the currently available toxicological database on the topic of nano-feed additives is not at all related to equines and even inadequate for other livestock species. This review aims to provide new insights into possible future research pertaining to the usage of nano-feed additives in equines.

Keywords: antimicrobial, drug delivery, equine nutrition, feed additives, nano-minerals, nanoparticles.

Isolation and characterization of Clostridium perfringens strains isolated from ostriches (Struthio camelus) in Vietnam

Research (Published online: 25-08-2020)

28. Isolation and characterization of Clostridium perfringens strains isolated from ostriches (Struthio camelus) in Vietnam

Tham Thi Nguyen, Hung Vu-Khac and Tan Duc Nguyen

Veterinary World, 13(8): 1679-1684

ABSTRACT

Background and Aim: Clostridium perfringens can cause enteritis in ostriches. The toxin release is believed to play a major role in determining pathogenesis properties of these pathogenic bacteria. This study was conducted to isolate and characterize C. perfringens strains from ostriches in Vietnam for identifying if particular virulence factors of these pathogenic bacteria are associated with enteritis progress in ostriches.

Materials and Methods: The prevalence of cpa, cpb, iA, etx, cpe, and cpb2 genes among C. perfringens isolates was determined by a multiplex polymerase chain reaction (PCR) method. The NetB toxin-encoding gene was detected by PCR and then sequenced to observe their variation. The expression of NetB toxin was checked by SDS-PAGE.

Results: A total of 116 C. perfringens isolates were obtained from 318 fecal samples and 105 intestinal organs. Of 80 isolates from fecal samples, 33 isolates were from healthy and 47 isolates were from diseased ostriches. The results of multiplex PCR showed that all 116 C. perfringens strains from healthy and enteric disordered ostriches were positive for the alpha toxin-encoding gene (cpa). The cpe and cpb2 genes were found in only one and five diseased ostriches, respectively. The netB gene was detected in 1/33 (3.03%) C. perfringens isolates from healthy ostriches, in 8/47 (17.05%) isolates from feces, and in 7/36 (19.44%) intestinal contents of diseased ostriches. The full-length sequences of 5 out of 15 netB-positive isolates from diseased ostriches showed 100% identity to each other as well as to the netB sequences available in GenBank. All of these five isolates produced NetB toxin in vitro.

Conclusion: Type A is the most prevalent among C. perfringens isolates from ostriches in Vietnam. Especially, the study provides data emphasizing the role of NetB toxin in causing necrotic enteritis by C. perfringens in ostriches.

Keywords: Clostridium perfringens, multiplex polymerase chain reaction, ostriches, toxin genes.

Lassa fever: History, causes, effects, and reduction strategies

Review (Published online: 25-08-2020)

1. Lassa fever: History, causes, effects, and reduction strategies

Promise Tewogbola and Norah Aung

International Journal of One Health, 6(2): 95-98

ABSTRACT

Lassa fever is a disease that is not well-known worldwide, particularly due to the inability of the multimammate rat, the primary vector of the Lassa virus, to breed in temperate regions. The aim of this review is to provide an overview of the disease and its modus operandi while also providing information about trends in the past decade, as well as proven strategies that have been used to manage its spread.

Keywords: Arenavirus, epidemic, epidemiology, Lassa fever, Lassa virus, virus.

Investigation of Trypanosoma evansi infection in bullfighting cattle in Southern Thailand

Research (Published online: 22-08-2020)

27. Investigation of Trypanosoma evansi infection in bullfighting cattle in Southern Thailand

Ketsarin Kamyingkird, Piangjai Chalermwong, Vannarat Saechan, Domechai Kaewnoi, Marc Desquesnes and Ruttayaporn Ngasaman

Veterinary World, 13(8): 1674-1678

ABSTRACT

Background and Aim: Trypanosoma evansi infection has been reported in Thai livestock such as beef and dairy cattle. However, there is little information on T. evansi infection in bullfighting cattle in Southern Thailand. The aim of this study was to investigate the infection of T. evansi in bullfighting cattle presented for health checks at the Animal Hospital, Faculty of Veterinary Science, Prince of Songkla University, Thailand.

Materials and Methods: Blood and serum samples were collected from 177 bullfighting cattle from April 2016 to February 2017 after bullfighting matches. Animal inspected showed signs of fever, weight loss, or exercise intolerance. Investigation of T. evansi infection was tested using polymerase chain reaction (PCR) with TBR primers and using indirect enzyme-linked immunosorbent assay with T. evansi crude antigen.

Results: The seroprevalence of T. evansi in bullfighting cattle was 22.60% (40/177). The PCR results detected no parasite DNA in this study. However, bullfighting cattle may serve as T. evansi reservoirs.

Conclusion: Health checking procedures for T. evansi should be promoted for bullfighting events so that infected animals can be quarantined in the preparatory stages of such events.

Keywords: bullfighting cattle, seroprevalence, Thailand, Trypanosoma evansi.