Bacterial isolation of milk samples submitted from clinical mastitis buffaloes during 2007 to 2016.

The present study determined trends in the isolation of bacterial pathogens in milk samples submitted from clinical mastitis buffaloes at the University mastitis laboratory during 2007 to 2016. Culture results (n = 3945) were classified into six categories (Staphylococcus spp., 28.7%; Streptococcus spp., 1%; Corynebacterium spp., 1.1%; gram-negative organisms, 3.2%; others including mixed growths, 3.3%; and no growth, 62.7%). Overall, culture results were significantly associated with year (χ2 = 112.28; df = 10; P < 0.001) and season (χ2 = 136.03; df = 20; P < 0.001). From 2007-2009 to 2013-2016, the isolation of Staphylococcus spp. increased from 28.2 to 48.4%, while isolation of Streptococcus spp. (50 to 20%) and Corynebacterium spp. (65.1 to 16.3%) decreased. The proportion of samples characterized as no growth increased from 26.4% (2007-2009) to 46.3% (2013-2016). Further, the proportion of clinical mastitis cases increased over the study years (goodness-of-fit χ2 = 59; df = 2; P < 0.001). With respect to season, the proportion of Staphylococcus spp. (30.6%; 346/1132), Corynebacterium spp. (48.8%; 21/43), and gram-negative bacteria (55.9%; 71/127) were more associated with the monsoon, and that of Streptococcus spp. (47.5%; 19/40) with the winter. Seasonal effects were also observed on the occurrence of clinical mastitis cases; comparatively, more clinical mastitis cases (35.6%; 523/1473) were observed during the monsoon season (goodness-of-fit χ2 = 276.7; df = 4; P < 0.001) as compared with other seasons. The present study concludes that Staphylococcus spp. are the major cause of intramammary infections in buffaloes with clinical mastitis, demanding more studies regarding its epidemiology and pathogenicity. Also, more efforts are needed in the prevention and control of clinical mastitis in buffaloes, especially, during the monsoon season.

Relationship between teat morphological traits and subclinical mastitis in Frieswal dairy cows.

The present study was aimed to investigate the relationship between selected morphological traits of teat and subclinical mastitis (SCM) in Frieswal crossbred dairy cows. A total of 1040 quarters from 261 lactating cows were evaluated for teat shape (bottle/fleshy/collapsed/conical/normal/pencil and short), teat-end shape (dished/flat/funnel/pocketed/pointed and rounded), teat orientation (aligned/misaligned) and teat position (front and rear; left-sided and right-sided). Each udder quarter was screened with California Mastitis Test (CMT) for the purpose of defining quarter health status. Data were analysed using Chi-square test and multivariable logistic regression procedure. An overall prevalence of SCM (CMT positive) at quarter level was 30.6%. Most of the teats had normal or cylindrical shapes (48%), dished teat-ends (40.7%), and aligned (central or squared) in orientation (65%). At bivariable level, significant association of SCM with teat shape, teat position, teat orientation, parity, and stage of lactation was observed (P < 0.05 to P < 0.001). Teat-end shapes showed some association with SCM (P = 0.07). Results of multivariable analysis showed that pencil-shaped teats were least associated with SCM (P < 0.05) as compared to other teat shapes. Prevalence of SCM was also higher in rear teats (P = 0.015), misaligned teats (P = 0.01), and cows in second or higher parities (P < 0.01) and late stage of lactation (P < 0.001). The results of the present study indicate that selected morphological traits of teat are associated with SCM in Frieswal crossbred cows; therefore, selection towards desirable morphological traits could help reduce mastitis in this breed.

Characterization of fertility associated sperm proteins in Aseel and Rhode Island Red chicken breeds.

This study focused on characterization of fertility associated proteins in Aseel and RIR roosters and was conducted on two generations of birds. Roosters were divided into high (>50%) and low fertility groups (<50%) based on sperm function tests and fertility rate in both the generations. Polyclonal antibodies were raised in rabbits against sperm proteins of first generation highly fertile roosters and tested for characterization of fertility associated sperm proteins in the second generation of same roosters. IgG-fraction against proteins (Anti-SP-IgG) was reacted with sperm proteins of both high and low fertile roosters of second generation on immunoblots. Sperm proteins present in highly fertile roosters were further characterized by Mass Spectrometry (MS). Use of SDS-PAGE for evaluation of sperm extracts of Aseel and RIR breeds resulted in resolution of 16 and 10 proteins on 12% acrylamide gels. Anti-SP-IgG reacted with eight and ten sperm proteins of Aseel and RIR roosters on immunoblots. The SDS-PAGE and immunoblotting analysis also indicated a variation in sperm proteins among two breeds and high/low fertile roosters. The MS analysis indicated matching of 20, 30, and 20, 25 kDa proteins (associated with high fertility rate) of Aseel and RIR roosters with immunoglobulin kappa chain variable, phospholipase A2 (PLA2), hypothetical N332-08551 partial and cystatin like partial proteins with a top score of 41, 46, 52 and 43, respectively. Considering the function and importance of matching proteins in male reproduction, these proteins may be further explored as potential markers for fertility evaluation of Aseel and RIR roosters.

Pharmacokinetic profile of erythromycin after intramammary administration in lactating dairy cows with specific mastitis.

The pharmacokinetics of erythromycin was studied in five lactating dairy cows following single intramammary infusion of 300 mg erythromycin in each of two quarters per cow with specific mastitis. Levels of erythromycin in plasma and quarter milk samples were measured by agar plate diffusion assay using Micrococcus luteus (ATCC 9341) as the test organism. Erythromycin level in plasma reached a peak concentration value (C(max)) of 0.07 +/- 0.01 microg/ml at 30 min; thereafter, levels declined gradually to reach 0.05 +/- 0.00 microg/ml 12 h post drug administration. The pharmacokinetic profile of the drug revealed mean absorption half life (t(1/2 ka)) as 0.26 +/- 0.05 h. The drug was eliminated slowly with elimination half-life (t(1/2 beta)) of 13.75 +/- 0.35 h and elimination rate constant (k(el)) of 0.04 +/- 0.00 h(-1). The volume of distribution based on the zero-time plasma concentration intercept of the least-squares regression line of the elimination phase (V(d(B))) was 0.032 L/kg. The drug crossed to untreated quarters also; mean drug levels of 0.20 +/- 0.07, 0.23 +/- 0.07, 0.17 +/- 0.04, and 0.17 +/- 0.04 microg/ml were found at 3, 6, 8 and 12 h, respectively. The mean drug concentration for treated quarters was measured as 22.97 +/- 2.31 microg/ml milk at first milking (12 h) following drug infusion. No apparent adverse reaction was seen in cows administered erythromycin. It is concluded that following intramammary infusion erythromycin diffuses readily and extensively in various body fluids and tissues and adequate concentration is maintained in udder tissues for at least 12 h post intramammary administration. Thus, erythromycin may be recommended for local therapy of acute mastitis caused by Gram-positive bacteria in lactating dairy cows.

Acute phase response in lame crossbred dairy cattle.

AIM: The study was undertaken to study acute phase response based on acute phase proteins (APPs) such as C-reactive protein (CRP), haptoglobin (Hp), serum amyloid A (SAA), and fibrinogen in lame crossbred dairy cattle. MATERIALS AND METHODS: Lame animals (n=30) were selected within 3-7 days of being noticed as lame by the farm veterinarian, from a local dairy farm in southeast Ludhiana over a period of 6 months, stratified proportionately with respect to stage of lactation with non-lame healthy cows (n=10). All the cows were otherwise healthy and did not have any other inflammatory problems such as pneumonia, enteritis, mastitis, or any kind of acute uterine inflammation. Blood samples were collected from all the animals; serum and plasma samples were separated and stored at -20°C. The levels of CRP, Hp, and SAA were estimated using Sandwich ELISA, whereas fibrinogen was estimated by heat precipitation method. RESULTS: SAA levels in lame cows were significantly higher (22.19±0.85 µg/ml), approximately 3 times as compared to non-lame cows (8.89±0.72 µg/ml), whereas serum Hp concentration was approximately 20 times higher in the lame cattle (21.71±3.32 mg/dl) as compared to non-lame cows (1.17±0.07 mg/dl). Fibrinogen also increased in the lame cattle (3.97±0.22 g/L) as compared to non-lame group (1.40±0.17 g/L). Serum CRP levels analyzed in the lame cattle for the first time in the present study, and significant high concentration was appreciated in lame cattle (4.41±0.33 mg/L) as compared to non-lame cattle (0.61±0.14 mg/L). Lame cattle were having more of sole hemorrhages, sole ulcers, and white line lesions as compared to non-lame cattle. CONCLUSION: It can be concluded that lame cattle exhibit high levels of APPs including CRP, Hp, SAA, and fibrinogen as compared to non-lame cattle.

Comparative antibiogram of coagulase-negative Staphylococci (CNS) associated with subclinical and clinical mastitis in dairy cows.

AIM: The present study was planned to determine the in vitro antibiotic susceptibility of coagulase-negative Staphylococci (CNS) strains isolated from clinical and subclinical cases of mastitis in dairy cows. Antibiotic sensitivity profile will be helpful to recommend early therapy at the field level prior to availability of CST results. MATERIALS AND METHODS: The milk samples from cases of clinical mastitis received in Mastitis Laboratory, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana and those of subclinical mastitis collected during routine screening of state dairy farms, were subjected to microbial culture. Identification of CNS organisms was done by standard biochemical tests. Antibiotic sensitivity testing, based on 30 antibiotics belonging to 12 groups, was done on 58 randomly selected CNS isolates (clinical isolates: 41, subclinical isolates: 17). RESULTS: Isolates were highly susceptible to chloramphenicol (98.3%), gentamicin (93.1%), streptomycin (91.4%), linezolid (91.4%), ceftixozime (87.9%), cloxacillin (86.2%), clotrimazole (86.2%), bacitracin (86.2%), enrofloxacin (84.5%) and ceftrioxone + tazobactum (70.7%), while resistance was observed against amoxicillin (77.6%), penicillin (75.9%), ampicillin (74.1%) and cefoperazone (51.7%). Overall, isolates from clinical cases of mastitis had a higher resistance than subclinical isolates. CONCLUSION: CNS isolates were susceptible to chloramphenicol, gentamicin and streptomycin, while higher resistance was recorded against routinely used penicillin group.

Para-clinico-pathological observations of insidious incidence of canine hepatozoonosis from a mongrel dog: a case report.

A rare case of canine hepatozoonosis in a mongrel dog with para-clinico-pathological observations has been reported. The study included detailed haemato-biochemical changes at two stages, i.e. before treatment and after treatment with adopted therapy. Before therapy, blood picture revealed normocytic hypochromic anaemia and neutrophilic leucocytosis with variable counts of platelets. Thirty-seven percent of neutrophils were found infected with gametocytes of Hepatozoon canis. Following treatment, further decrease in haemoglobin value with a relative increase in lymphocyte count was seen. Biochemically, increase in alkaline phosphatase, blood urea nitrogen and creatinine levels along with hyperproteinemia was seen. The 14 days chemotherapy did not bring a respite for the dog and the level of parasitaemia was 33% after the treatment. The alkaline phosphatase and creatinine level further rose up following therapy with sulphadiazine and clindamycin. Continual study is required to explain the best possible therapeutic combination to deal H. canis.

Mucormycosis of the bovine udder.

Nine cross-bred cows suffering from mucormycosis of the udder were observed. Histopathological and cultural examination of the lesions revealed the presence of Mucor spec.