Association between milk urea nitrogen and first service conception in smallholder dairy farms under heat and humidity stress

Research (Published online: 22-11-2018)

13. Association between milk urea nitrogen and first service conception in smallholder dairy farms under heat and humidity stress

Suppada Kananub, John A. VanLeeuwen and Pipat Arunvipas

Veterinary World, 11(11): 1604-1608

ABSTRACT

Aim: The study was to evaluate the relationship between the first service conception (FSC) and milk urea nitrogen (MUN) in smallholder dairy farms under heat and humidity stress.

Materials and Methods: Dairy cows from 43 dairy farms giving birth between November 2014 and April 2015 (n=295) contributed to the study. All cows were sampled monthly to measure milk compositions, and we collected additional farm data from farmers through a questionnaire. The first service during the first 120 days of lactation was the outcome of interest in this study. Multivariable logistic regression determined significant associations with FSC.

Results: The overall FSC was 22% and the mean MUN concentration was 11.55 mg/dl. The final FSC model included MUN concentration, the season of breeding, and protein energy ratio (PE ratio) in the diet. The odds of FSC were reduced by approximately 10% for each mg/dl higher MUN on the day of the milk sample that was nearest to the artificial insemination (AI) day. The odds of FSC were nearly 3 times higher when the first insemination occurred in winter compared to summer first services. Taking into account the nutritional factors, the odds of FSC were nearly 70% higher with an increase in PE ratio of 10 g of crude protein/Mcal from the mean of 35.90 g.

Conclusion: This study of smallholder dairy farmers in the hot and humid climate of Thailand confirmed that season, nutritional management, and MUN concentration were associated with FSC. MUN appears to be a useful indicator to monitor the effects of diet on reproductive performance from this study.

Keywords: first service conception, milk urea nitrogen, smallholder farm.

Validation of real-time reverse transcription polymerase chain reaction to detect virus titer and thermostability of Newcastle disease live virus vaccine

Research (Published online: 20-11-2018)

12. Validation of real-time reverse transcription polymerase chain reaction to detect virus titer and thermostability of Newcastle disease live virus vaccine

Pangkaj Kumar Dhar, Avijit Dutta, Avijit Das, Mohammad Shah Jalal, Himel Barua and Paritosh Kumar Biswas

Veterinary World, 11(11): 1597-1603

ABSTRACT

Background and Aim: Newcastle disease is one of the most common diseases affecting poultry in Bangladesh. The disease can cause up to 100% mortality but is preventable if birds are timely and properly vaccinated with a vaccine of standard virus titer. Different live vaccines are commercially available in the country - most, if not all, are produced using lentogenic strains of the virus with variable virulence. One of the disadvantages of these vaccines is that they are not stable at high environmental temperature, and therefore, a proper cold chain must be maintained during transportation and storage. Information on how long these vaccine viruses can withstand environmental temperature, which is near the vicinity of 37°C in the summer season in Bangladesh, is scanty. The aim of this research was to measure the effect of temperature on virus titer of live ND virus vaccines and to develop a real-time reverse transcription polymerase chain reaction (rRT-PCR) standard curve to indirectly determine hemagglutination (HA) titer of virus by this highly sensitive method.

Materials and Methods: In this study, thermostability of five commercial live vaccines containing LaSota, F, Clone 30, and B1 type LaSota strains was observed for up to 35 days keeping them at 37°C. From the most thermostability yielding sample, two rRT-PCR standard curves were developed: (1) By plotting the cycle threshold (CT) values as obtained from 10-fold serial dilutions up to 10-3 against their corresponding log (to the base 10) dilutions and (2) by plotting the CT values obtained from serial HA dilutions up to 2-4 against their corresponding HA titer dilutions. The PCR efficiencies based on which the graphs were fitted were also evaluated.

Results: The vaccine from the LaSota strain withstood 37°C for 35 days with a gradual declination of HA titer over time, and this vaccine also had the highest initial HA titer, which was 211. The vaccine made from F strain was inactivated quickly, and it had the lowest HA titer at the beginning of the study. The first standard curve developed can be used to assess the level of virus titer in a diluted sample compared with the titer in the original undiluted vaccine preparation by plotting the CT value obtained from the dilution by rRT-PCR. The second standard curve can be used to calculate the HA titer of a vaccine dilution by plotting the CT value as obtained from the dilution by rRT-PCR.

Conclusion: The regression equations for the first and second graphs were y=–3.535x+14.365 and y=–1.081x+13.703, respectively, suggesting that, for every 3.53 cycles, the PCR product would have increased 10 times and 2 times for every 1.08 cycles, respectively, indicating nearly (but not exactly) 100% PCR efficiency.

Keywords: LaSota strain, Newcastle disease, real-time reverse transcription polymerase chain reaction, thermostability, vaccine, validation.

Effect of feeding rice based distillers dried grains with solubles and gluten meal on nutrient transporter genes and immunity in broiler chickens

Research (Published online: 20-11-2018)

11. Effect of feeding rice based distillers dried grains with solubles and gluten meal on nutrient transporter genes and immunity in broiler chickens

Om Prakash Dinani, Pramod Kumar Tyagi, Asit Baran Mandal, Praveen Kumar Tyagi, Dukare Sagar Popat and Sita Prasad Tiwari

Veterinary World, 11(11): 1592-1596

Aim: The aim of this study was to investigate the effect of feeding rice based distillers dried grains with solubles (rDDGS) and gluten meal on nutrient transporter genes and immunity in broiler chickens.

Materials and Methods: A 2×3 factorial design resulted in six experimental diets, namely T1 (no rDDGS/rice gluten meal [RGM]/enzyme), T2 (no rDDGS/RGM, with multienzymes), T3 (12.5% rDDGS, 15% RGM, no enzyme), T4 (12.5% rDDGS, 15% RGM, with protease enzyme), T5 (10% rDDGS, 12.5% RGM, no enzyme), and T6 (10% rDDGS, 12.5% RGM, with protease enzyme). Each treatment was allocated five replicates of chicks, with eight birds in each. Nutrient transporter genes such as Mucin (MUC 2), excitatory amino acid transporter 3 (EAAT3), and peptide transporter (PepT1) and immunity were estimated using standard procedures.

Results: Feeding rDDGS and RGM combination improved humoral immunity, while cell-mediated immunity did not show any significant (p>0.05) effect on broiler chickens. MUC and PepT1 genes showed significantly (p<0.01) decreased relative fold expression in 12.5% rDDGS +15% RGM combination, while EAAT3 gene showed significantly (p<0.01) decreased relative fold expression in both rDDGS and RGM combination levels.

Conclusion: Thus, it may be concluded that feeding rDDGS and RGM combination improved humoral immunity but had an adverse effect on nutrient transporter gene in broiler chickens.

Keywords: broiler, immunity, nutrient transporter genes, protease, rice distillers dried grains with solubles, rice gluten meal.

Detection of gastrointestinal parasites in small-scale poultry layer farms in Leyte, Philippines

Research (Published online: 19-11-2018)

10. Detection of gastrointestinal parasites in small-scale poultry layer farms in Leyte, Philippines

Rochelle Haidee D. Ybañez, Kurt Jimwell G. Resuelo, Ara Patrice M. Kintanar and Adrian P. Ybañez

Veterinary World, 11(11): 1587-1591

ABSTRACT

Background: Gastrointestinal (GIT) parasites can affect poultry productivity by compromising its health. It is well studied in other countries, but the documented reports in the Philippines have been limited.

Aim: The aim of the present study was to evaluate the presence of GIT parasites in selected small-scale poultry layer farms in Leyte, Philippines.

Materials and Methods: A total of 243 stool samples from eight small-scale poultry layer farms in Leyte, Philippines, were examined for GIT parasites using floatation and sedimentation technique. Profile parameters were also obtained. Fecal samples were collected and analyzed using floatation and sedimentation techniques. Statistical significance between GIT parasite positivity and profile parameters was determined using Chi-square test.

Results: GIT parasites were detected in 92.2% of the samples (24.7% with single infection, 42.0% with 2-3 parasites, and 25.5% with three or more parasites). The common parasites detected were Ascaridia spp. (41.2%), Heterakis spp. (59.3%), Capillaria spp. (10.7%), Eimeria spp. (43.2%), and Strongyloides spp. (74.1%). Some profile parameters, including farm location, years in business, number of workers, nearby water system, the practice of fecal cleaning, and presence of other animals, were found to be significantly associated with GIT positivity.

Conclusion: GIT parasites were detected in the poultry of small-scale layer farms in selected areas in Leyte, Philippines. This finding calls for the importance of routine GIT parasite monitoring and the implied need for regular deworming or dewormer rotation in the area.

Keywords: gastrointestinal parasites, layer chickens, Leyte, Philippines, small-scale farms.

Molecular detection of genes encoding resistance to tetracycline and determination of plasmid-mediated resistance to quinolones in avian pathogenic Escherichia coli in Sukabumi, Indonesia

Research (Published online: 18-11-2018)

9. Molecular detection of genes encoding resistance to tetracycline and determination of plasmid-mediated resistance to quinolones in avian pathogenic Escherichia coli in Sukabumi, Indonesia

Ryan Septa Kurnia, Agustin Indrawati, Ni Luh Putu Ika Mayasari and Adin Priadi

Veterinary World, 11(11): 1581-1586

ABSTRACT

Aim: This study aimed to identify genes encoding resistance to tetracycline (TE) and plasmid-mediated resistance to quinolones in Escherichia coli isolates from clinical cases of avian colibacillosis in Sukabumi, Indonesia.

Materials and Methods: A total of 25 E. coli archive isolates were collected in 2013-2017 from clinical cases of avian colibacillosis in Sukabumi, Indonesia. All isolates were tested for TE and quinolone resistance using the disk diffusion method. TE -resistant E. coli isolates were screened for the presence of tet(A) and tet(B) genes by single polymerase chain reaction (PCR). The qnr(A), qnr(B), and qnr(S) genes were detected by multiplex PCR in quinolone-resistant E. coli isolates.

Results: Result of this study shows that 19 of 25 (76%) E. coli isolates are resistant to oxytetracycline and 64% are resistant to TE; among them, 63.2% and 31.5% were positive tet(A) and tet(B), respectively. 13 out of 25 (52%) are resistant to ciprofloxacin and 36% are resistant to enrofloxacin either norfloxacin; among them, 61.6% were positive qnr(A), 7.7% were positive qnr(B), 23% were positive qnr(S), and 7.7% were positive both of qnr(A) and qnr(S).

Conclusion: This study shows that a few pathogens of E. coli are resistant to TE and quinolone. The frequency of tet and qnr genes that are responsible for this resistance among avian pathogenic E. coli isolates in Sukabumi, Indonesia, was high.

Keywords: Antibiotic, colibacillosis, Escherichia coli, genes, resistance.

Corynebacterium pseudotuberculosis mastitis in Egyptian dairy goats

Research (Published online: 13-11-2018)

8. Corynebacterium pseudotuberculosis mastitis in Egyptian dairy goats

A. M. Nabih, Hany A. Hussein, Safaa A. El-Wakeel, Khaled A. Abd El-Razik and A. M. Gomaa

Veterinary World, 11(11): 1574-1580

ABSTRACT

Background and Aim: Mastitis is an important threat facing goat milk industry and is the most common cause of culling. Efficient control of mastitis, based on efficient diagnosis of diseased animals, would improve milk production and reproductive efficiency. In subclinical mastitis (SCM), infected goats demonstrate neither udder symptoms nor abnormal milk. Corynebacterium pseudotuberculosis is an infectious causative agent of mastitis, mostly results as an extension of infection from the supramammary lymph node, and causes financial losses in the goat industry. This study aimed to estimate the prevalence of SCM with emphasis on C. pseudotuberculosis mastitis in Egyptian dairy goats in the selected farms.

Materials and Methods: A total of 336 half milk samples were collected from 177 dairy goats of various crossbreeds, in mid-to-late lactation period, after clinical examination. All samples were examined bacteriologically, while somatic cell count (SCC) was determined only in 180 half milk samples of the clinically healthy milk samples. The isolated and identified C. pseudotuberculosis was examined for evidence of virulence genes (Phospholipase D [pld] and β-subunit of RNA polymerase [rpoB]) by polymerase chain reaction (PCR).

Results: The prevalence of clinical mastitis was 30.5%, while 69.5% of animals were apparently healthy and secreted milk was normal. Of those 180 clinically healthy half milk samples, 96 milk samples (53.33%) showed SCM as detected by SCC (SCC ≥1,000,000 cells/ml). Coagulase-negative staphylococci were the most prevalent bacteria (41.96%), then Staphylococcus aureus (37.5%) and C. pseudotuberculosis (7.14%). Molecular diagnosis of virulence genes revealed evidence of pld gene in 16 isolates (66.66%), and rpoB gene in 6 samples (25%) of the 24 bacteriologically isolated C. pseudotuberculosis. Here, we describe, for the 1st time, isolation and identification of C. pseudotuberculosis from milk of does suffering from SCM in Egypt.

Conclusion: C. pseudotuberculosis must be considered for routine bacteriological examination of milk from dairy goats, particularly herds with a history of caseous lymphadenitis. Pld gene-based PCR is more reliable than rpoB gene-based ones for the diagnosis of C. pseudotuberculosis.

Keywords: bacteriological investigation, caprine, Corynebacterium pseudotuberculosis, mastitis, phospholipase D, β-subunit of RNA polymerase.

Prevalence of coccidian infection in rabbit farms in North Algeria

Research (Published online: 12-11-2018)

7. Prevalence of coccidian infection in rabbit farms in North Algeria

Samia Maziz-Bettahar, Miriem Aissi, Hacina Ainbaziz, Mohamed Sadek Bachene, Safia Zenia and Fairouz Ghisani

Veterinary World, 11(11): 1569-1573

ABSTRACT

Aim: The aim of the present study was to determine the prevalence and intensity of rabbit coccidiosis (Oryctolagus cuniculus) in North Algeria.

Materials and Methods: During the study, 40 rabbit farms were investigated. The farms are located in the provinces of Tizi Ouzou, Medea, and Djelfa which distributed, respectively, into three regions: East Tell Atlas Mountains, Central Tell Atlas Mountains, and High Plateaus. The number of oocyst per gram of feces (OPG) was determined by McMaster technique, and the Eimeria species were identified using morphological criteria.

Results: In the farms investigated, the prevalence of coccidian infection was estimated to 90% (80.7-99.3%) in rabbits after weaning. The classification of the farms according to their parasite load allowed us to show that 37.5% of the prospective farms have an oocyst excretion between 104 and 5×104 oocysts per gram and 22.5% excrete >5×104 oocysts per gram. Excretion levels by region show that the region of East Tel Atlas Mountains ranks first with 79% of farms with a parasitic load >104 coccidians compared to the regions of Central Tel Atlas Mountains and High Plateaus. In total, eight species of Eimeria were identified from oocyst-positive samples. Mixed infections with four Eimeria species were common. E. magna is the dominant species in comparison with E. media and E. irresidua with respective frequencies of 42.5% and 17.6% and 14.9% (p<0.001). Our results showed that the farms using anticoccidial drugs for their rabbits were low (25%) and the percentage of farms with poor hygienic conditions was 65%. There was a significant association between increased oocysts excretion and control measures of coccidian infection.

Conclusion: The study revealed an overall prevalence of 90% in the three Algerian regions. A strong association was observed between Eimeria infection and hygienic status and preventional chemotherapy.

Keywords: Algeria, coccidiosis, Eimeria, oocysts, prevalence, rabbit.