Evaluation of brucellosis RB51 vaccine for domestic water buffalo (Bubalus bubalis) in Trinidad

Thirty-two young domestic water buffalo (Bubalus bubalis) were obtained from a brucellosis-free farm to determine effectiveness of RB51 vaccination for prevention of Brucella infection under natural-exposure conditions in Trinidad. Study animals (20 males and 12 females 5–20 months old) were assigned to vaccination or control groups, using a block randomization design ensuring equal sex distributions between groups. The vaccination group received commercially available RB51 at the recommended calfhood dose of (1.0–3.4)×10¹⁰ colony-forming units (CFU) and controls received 2 ml sterile saline. Vaccination did not result in positive serologic results as measured by four traditional agglutination tests: standard tube agglutination test (STAT), standard plate agglutination test (SPAT), buffered plate agglutination test (BPAT), and card agglutination. Study animals were maintained in a brucellosis-positive herd in southern Trinidad with an estimated 56% prevalence to allow for natural exposure to B. abortus, which was evaluated using STAT, SPAT, BPAT, and card tests. Animals were sampled seven times over 2 years and were classified as positive if they had persistent agglutination titers or had Brucella isolated from specimens collected at completion of the study. Five of the original 32 study animals were lost to follow-up during the field trial. Six of the 14 (43%) vaccinated animals completing the study were classified as positive for Brucella infection—as were two of the 13 (15%) control animals (P=0.21). Isolates from four vaccinates and one control were confirmed as B. abortus biovar 1.     

Prenatal development of retina in buffalo (Bubalus bubalis)

The development of retina in Indian buffalo (Bubalus bubalis) has not been reported previously. The aim of the present study was therefore to report the major landmarks and the time course in the development of retina. Serial histological sections of Indian buffalo embryos and foetuses were used as group1 (<20.0 cm CVRL), group2 (>20.0 but <40.0 cm CVRL) and group3 (>40.0 cm CVRL). Age estimation was made on the basis of crown vertebral‐rump length (CVRL), which ranged between 36 and 286 days (1.6–94.0 cm). The retina in Indian buffalo was developed in a similar manner to that of the other mammals with the principal differences in the time of occurrence of various layers of this nervous tunic. In 36 days (1.6 cm stage), the foetal retina was composed of pigmented layer and the layer of neuroblasts. Differentiation of layers was first observed in 47 days (4.0 cm CVRL) which became prominent in 52 days (5.1 cm stage). At 120 days (20.5 cm stage), the differentiation of inner plexiform layer and inner nuclear layer was evident. At 143 days (31.0 cm) foetal age, the faint line in neuroblastic layer was the first evidence of the future outer plexiform layer. In foetuses of group III, the retina was comprised of all 10 layers (eight cell layers and two membranes) viz. pigmented epithelium, layer of rods and cones, outer limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer, ganglion cell layer, layer of nerve fibres and the inner limiting membrane.     

Comparison of carcass and meat characteristics of Brahman grade cattle (Bos indicus) and crossbred water buffalo (Bubalus bubalis)

This study was conducted to determine and compare the live traits, carcass yield and the physical, chemical, processing and sensory properties of meat from 20 Brahman grade cattle (crossbred cattle) and crossbred water buffalo (Philippine carabao × Murrah, Bulgarian or Indian) with an average age and weight of 29 months and 434 kg, respectively. The animals were fed a similar diet for 180 days before slaughter. A survey was performed to establish consumer meat preference between the two species. Live weights before slaughter of the two species were found to be different (P < 0.05) with the crossbred water buffalo showing higher bodyweight. However, the crossbred water buffalo had a lower (P < 0.05) dressing yield based on hot carcass weight and chilled carcass weight. The lower dressing yield of crossbred water buffalo can be attributed to its higher (P < 0.05) weights of edible and non‐edible slaughter by‐products. The chilled carcass yield of the forequarters and hindquarters from crossbred cattle and crossbred water buffalo were comparable when expressed as percent of live weight and chilled carcass weight. The estimated lean yield was higher in crossbred cattle than crossbred water buffalo. Crude protein, ash, fat, cholesterol, myofibrillar, sarcoplasmic and insoluble protein contents of the beef and carabao meat were all similar. Water holding capacity, pH, muscle fiber diameter, tenderness, firmness and marbling score in carabeef were all comparable to the beef. Redness was found to be higher (P < 0.05) in carabeef than the beef as measured with a color meter. The consumer meat preference survey showed that 55.9% selected the beef while 44.1% preferred carabeef. The color and amount of fat on the outside of the beef sample were primary in buyer selection.     

Subcutaneous pharmacokinetics and dosage regimen of cefotaxime in buffalo calves (Bubalus bubalis)

The pharmacokinetics and dosage regimen of cefotaxime following its single subcutaneous administration (10 mg/kg) were investigated in buffalo calves. Plasma and urine samples were collected over 10 and 24 h post administration, respectively. Cefotaxime in plasma and urine was estimated by microbiological assay technique using E. coli as test organism. The pharmacokinetic profiles fitted one-compartment open model. The peak plasma levels of cefotaxime were 6.48 ± 0.52 µg/ml at 30 min and the drug was detected upto 10 h. The absorption half-life and elimination half-life were 0.173 ± 0.033 h and 1.77 ± 0.02 h, respectively. The apparent volume of distribution and total body clearance were 1.17 ± 0.10 l/kg and 0.45 ± 0.03 l/kg/h, respectively. The urinary excretion of cefotaxime in 24 h, was 5.36 ± 1.19 percent of total administrated dose. A satisfactory subcutaneous dosage regimen for cefotaxime in buffalo calves would be 13 mg/kg repeated at 12 h intervals.     

Disposition kinetics and urinary excretion of gentamicin in buffalo bulls (Bubalus bubalis)

The disposition kinetics and urinary excretion of gentamicin sulphate were studied in young buffalo bulls following a single intramuscular administration of the drug at 5 mg kg^-1 body weight. The time course of the serum gentamicin concentration was adequately described by the one-compartment open model. The values of the absorption and elimination halflives were 12.2±2.2 and 167.0±29.7 min respectively. The apparent volume of distribution was 0.29±0.01 L kg^-1. During the first 12 h, 63% of the total administered dose was excreted in urine. On the basis of the kinetic data, a satisfactory intramuscular dosage regimen for gentamicin sulphate would be at least 6 mg kg^-1 body weight repeated at 8 h intervals.     

Toxocara vitulorum in the milk of buffalo (Bubalus bubalis) cows

The duration of excretion of Toxocara vitulorum larvae in the milk of buffalo cows determines the optimum time for treating calves. Studies on 10 cows showed that a few larvae occur in the colostrum of some cows before the calf has suckled, but most are present from the day after calving and for a further five days. From day 9 onwards, very few larvae were found in the milk. The total number of larvae found was comparable with the number of adult parasites collected from the calves of cows with similar histories. The larvae were 1254 +/- 60 microns long and 36 +/- 6.7 microns in diameter at the ventriculus, figures which are substantially different from some published results.     

Comparison of fattening performance in Brahman grade cattle (Bos indicus) and crossbred water buffalo (Bubalus bubalis) fed on high roughage diet

The objective of this study was to compare the fattening performance in Brahman grade cattle (crossbred cattle) and crossbred water buffalo at the same young age and fed with high roughage based fattening rations in the Philippines. Ten crossbred cattle and 10 crossbred water buffalo, aged between 18 and 24 months old were used in this experiment. The animals were fed diets consisting of 85% Napier or Para grass and 15% concentrate mixture (CM) on a dry matter (DM) basis. The grass, total DM intake and bodyweight gain were significantly (P < 0.01) higher for the crossbred water buffalo than for the cattle. There was no species significant difference in the digestion coefficient and feed conversion rate between the crossbred cattle and water buffalo. The return over feed cost for fattening was significantly (P < 0.05) higher in the crossbred water buffalo than in the cattle. These results clearly indicate that under high roughage‐based fattening rations, young crossbred water buffalo are better able to utilize the roughage and they perform better in terms of feed intake and live weight gains than the crossbred cattle in the Philippines.     

Comparison of feed intake, digestibility and fattening performance of Brahman grade cattle (Bos indicus) and crossbred water buffalo (Bubalus bubalis)

Twenty growing crossbred cattle and crossbred water buffalo (carabao) with an average age of 22 (18–24 months) months were equally distributed into two treatment groups according to species. The animals were fed with the same ration made up of corn silage (50%) + wet brewer's spent grain (30%) + concentrate mixture (20%), and their fattening performance was monitored. The digestibilities of the different nutrients were likewise determined. The economics of raising the animals under intensive production system was calculated. Species differences did not influence total dry matter intake of the animals, when expressed as percentage of the bodyweight and per metabolic body size. There were no significant differences in digestion coefficients of the different nutrients, except for crude protein in crossbred water buffalo and crossbred cattle, although the digestibility of dry matter, organic matter and nitrogen free extract tended to be high in the former than in the latter. Likewise, average daily gain (ADG) was similar, although crossbred water buffalo had numerically higher ADG (828.6 vs 785.5 g) than crossbred cattle during the 6 months feeding. During the first 3 months of feeding (1–90 days), the ADG of crossbred water buffalo was 1066.1 g compared to 940.1 g for crossbred cattle. From 91 to 180 days, the crossbred cattle had slightly higher ADG (630.1 vs 591.1 g) but also the difference was not significant. The return above feed cost was comparable for crossbred cattle and crossbred water buffalo during the first 90 days of feeding. However, extending the feeding period from 91 to 180 days , income over feed cost was higher (P < 0.05) for crossbred cattle by PhP 5.3/kg gain than crossbred water buffalo. Results showed that crossbred water buffalo could attain similar growth rate with that of crossbred cattle under intensive system, when fed with high quality feed materials.     

Theca cell-conditioned medium enhances steroidogenesis competence of buffalo (Bubalus bubalis) granulosa cells

Theca cells (TCs) play a crucial role in follicular development and atresia. TCs synthesize androgens that act as substrate for granulosa cells (GCs) aromatization to oestrogens needed for follicular growth. However, the effects of TCs in the form of conditioned medium on steroidogenesis in buffalo GCs remain unclear. In the present study, the impacts of TC-conditioned medium (TCCM) on oestrogen synthesis in buffalo GCs were examined. The results showed that TCs secreted principally testosterone, but almost no androstenedione or oestradiol into TCCM. TCs at passage 3 had a stronger secretion capacity of testosterone in TCCM. Furthermore, TCCM collected at 72 hr improved both the expression levels of oestrogen synthesis-related genes (CYP11A1, CYP19A1, 3β-HSD and 17β-HSD) and the secretion levels of estradiol in GCs. The treatment of 72 hr in TCCM promoted both the expression levels of oestrogen synthesis-related genes (CYP11A1, CYP19A1 and 3β-HSD) and the secretion levels of estradiol in GCs. Besides, TCCM that was collected at 72 hr and applied to GCs for 72 hr (72 & 72 hr) improved the sensitivity of buffalo GCs to FSH. This study indicates that TCCM (72 & 72 hr) enhances the steroidogenesis competence of GCs mainly through facilitating the responsiveness of GCs to FSH in buffalo.     

Prevalence of antibodies against Bubaline herpesvirus (BuHV-1) among Mediterranean water buffalo (Bubalus bubalis) with implications in buffalo trade

Background: Both Bovine herpesvirus (BoHV-1) and Bubaline herpesvirus (BuHV-1) have been reported to cross the species barrier. Antibody seroconversion in glycoprotein E (gE) blocking ELISA during BuHV-1 infection has been documented. Recent diagnostic efforts have focused on the development and application of discriminatory tests to distinguish between infections with BoHV-1 and BuHV-1.

Objective: To evaluate the impact and distribution of these two infections in water buffalo farms in two regions (Piedmont (n = 3) and Campania (n = 10), Italy) where infectious bovine rhinotracheitis control programs have been implemented.

Animals and methods: Sampling was carried out on 13 buffalo farms comprising 1089 animals using specific gE-indirect ELISA's test able to discriminate among BoHV-1 and BuHV-1 infections.

Results: 59.0% of animals reacted positive to ELISA (irrespective of whether BoHV-1 or BuHV-1 antigen was used) and 86.4% of these were reactive to BuHV-1 only, whereas 11.8% showed absorbance values for both antigens and were classified as inconclusive. There was a statistically significant age-related difference in BuHV-1 infection rates but not in overall individual (47% vs. 58%) or herd prevalence (100% vs. 90%) of infection between the two regions.

Conclusion: The low percentage of sera reactive to BoHV-1 (1.8%, 12/643) indicates that BuHV-1 may be the main circulating alphaherpesvirus infection in Mediterranean water buffalo in the two study areas. Since Bubalus bubalis is included in Directive 64/432/EEC on animal health problems affecting intra-community trade in bovine animals, diagnostic testing with nonspecific ELISA for BoHV-1 infection in buffalo may yield false-positive reactions. This scenario could lead to economic losses and hamper buffalo trade and movement, particularly for reproduction purposes.     

Comparison of carcass and meat characteristics of Brahman grade cattle (Bos indicus) and crossbred water buffalo (Bubalus bubalis) fed on high roughage diet

The objective of this study was to compare the carcass and meat quality in crossbred cattle and crossbred water buffalo at the same younger age and fed with high roughage in the Philippines. Ten crossbred cattle and 10 crossbred water buffalo, with an average age of 22 months (18–24 months) were used in this experiment. The animals were fed a similar diet, which consisted of 85% Napier or Para grass and 15% concentrate mixture on a dry matter basis, for 180 days before slaughter. Slaughter weight of the crossbred water buffalo was higher (P < 0.05) than that of the cattle, although the dressing percentage was significantly (P < 0.01) lower for the former than for the latter. The estimated lean yield was higher (P < 0.05) in crossbred cattle than crossbred water buffalo. The muscle fiber diameter of loin in buffalo meat was smaller (P < 0.05) than that in cattle. In regard to carcass and meat quality, the crossbred water buffalo was comparable or slightly superior to the crossbred cattle in tenderness, sensory score of color (P < 0.01) and flavor (P < 0.05). These results clearly indicate that at a younger age and even under high roughage‐based fattening rations, crossbred water buffalo are able to produce good quality meat, which will be by no means inferior to that of crossbred cattle in the Philippines.     

Detection of prion gene promoter and intron1 indel polymorphisms in Anatolian water buffalo (Bubalus bubalis)

Bovine spongiform encephalopathy (BSE) is a fatal disease caused by miss folded prion protein. Studies in the cattle, comparing genetic data from BSE diseased and healthy animals have shown that indel polymorphisms in the promoter and intron 1 of PRNP gene were associated with disease susceptibility. Several studies were conducted to find out allele and genotypic frequencies of indel polymorphisms in promoter and intron 1 of the cattle PRNP gene. Unlike domestic cattle and bison, no indel polymorphisms of the PRNP promoter and intron 1 were examined in any population of the water buffalo (Bubalus bubalis). Aim of this study was to analyse frequencies of allele, genotype, and haplotype of the indel polymorphisms (23 bp indel in promoter and 12 bp indel in intron 1) in prion protein coding gene (PRNP) of water buffalo. Therefore a PCR based procedure, previously used in cattle to detect indel polymorphisms of PRNP promoter and intron 1 locus, was applied to 106 Anatolian water buffalo DNAs. Our results have revealed high frequency of in variants and in23/in12 haplotype for PRNP promoter and intron 1 indel polymorphisms in water buffalo. The results of the study have demonstrated that frequencies of allele, genotype, and haplotype of the indel polymorphisms in PRNP gene of the Anatolian water buffalo are significantly different those from cattle and bison PRNP indel polymorphisms.     

Histology,histochemistry and ultrastructure of the nasopharyngeal tonsil of the buffalo (Bubalus bubalis)

The light microscopic appearance and ultrastructure of the nasopharyngeal tonsil (tonsilla pharyngea), collected from 12 adult buffaloes of local mixed breed, were explored for the distribution of different types of epithelia, lymphoid tissue and high endothelial venules. The tonsillar mucosa was lined by pseudostratified columnar ciliated epithelium having goblet cells. The respiratory epithelium associated with the underlying lymphoid tissue formed the lymphoepithelium. The epithelium was further modified into follicle‐associated epithelium (FAE) characterized by reduced epithelial height, presence of a few dome‐shaped cuboidal cells equivalent of the M‐cells and absence of goblet and ciliated cells. The lymphoid tissue was distributed in the form of isolated lymphoid cells, diffuse lymphoid tissue and lymphoid follicles, mainly distributed within the propria‐submucosa along with the sero‐mucous glandular tissue. The goblet cells of the respiratory epithelium and the acinar cells contained different mucopolysaccharides. Scanning electron microscopy of the surface mucosa demonstrated a dense mat of cilia, island‐like arrangement of microvillus cells, M‐cells and a few brush‐like cells. The transmission electron microscopy revealed the different cell organelles of the respiratory epithelium and the FAE. Lymphocyte migration via the high endothelial venules in the propria‐submucosa was also observed.     

Comparison of two methods of seminal plasma removal on buffalo (Bubalus bubalis) sperm cryopreservation

Cryopreservation causes damage to spermatozoa, and methods minimizing this damage are therefore needed. Although much discussed, seminal plasma removal has become an alternative to improve sperm quality and viability after freezing and has been applied to different species in attempt to obtain good results. The objective of this study was to evaluate semen quality in buffaloes submitted to two methods for seminal plasma removal (filtration and centrifugation). Semen samples were collected from seven Murrah buffalo bulls (Bubalus bubalis) once a week for 8 weeks. Each ejaculate was divided into three groups: control (presence of seminal plasma), centrifugation and filtration. Sperm kinetics was evaluated with the computer‐assisted sperm analysis (CASA) system. Plasmalemma and acrosomal membrane integrity, mitochondrial membrane potential and reactive oxygen species (ROS) were measured by flow cytometry, and lipid peroxidation was evaluated by the thiobarbituric acid reactive substances (TBARS) assay. Seminal plasma removal did not improve sperm kinetics compared to the control group. Centrifugation increased the number of cells with damaged acrosomal membranes (0.77 ± 0.05) and filtration caused greater plasmalemma and acrosomal membrane damage (22.18 ± 1.07). No difference in the mitochondrial membrane potential was observed between groups. In contrast, ROS production was higher in the centrifugation group compared to the control and filtration groups, although no differences in TBARS formation were detected. In conclusion, seminal plasma removal did not improve the quality of thawed buffalo semen compared to control in terms of sperm kinetics, membrane integrity, mitochondrial membrane potential or lipid peroxidation.     

Ultrastructure changes in buffalo (Bubalus bubalis) oocytes before and after maturation in vitro with sericin

The aim of this research was to identify the changes in the cytoplasmic ultrastructure of immature and matured oocytes in buffalo (Bubalus bubalis ). Oocytes were matured in vitro in tissue culture medium?199 with and without sericin, and then analyzed by light and transmission electron microscopy. The experiment result showed that the nuclear maturation rate of buffalo oocytes was significantly higher in the presence of sericin (80.6%) than without sericin (68.1%) (P  < 0.05). The immature oocytes were characterized by cortical granule clusters in the ooplasm and the absence of perivitelline space (PVS ). In contrast, the oocytes matured either with or without sericin showed the formation of PVS , erected microvilli, the migration of cortical granules to the cytoplasmic periphery, and the clear appearance of the mitochondria and vesicle in the oolemma. Interestingly, matured oocytes with sericin have smaller cortical granules than do immature oocytes (P  < 0.05). In conclusion, supplementation of 0.05% sericin in the maturation medium can enhance the maturation rate of buffalo oocytes. Several cytoplasmic ultrastructures were relocated and modulated during the in vitro maturation process of buffalo oocytes: PVS development, cortical granules migration to periphery, and mitochondria and vesicles in the cortical region. The ultrastructure was similar between the groups with and without sericin.     

Seroprevalence and risk factors associated with exposure of water buffalo (Bubalus bubalis) to Neospora caninum in northeast Thailand

Water buffalo are important draft animals for agriculture in resource-restricted areas worldwide. Water buffalo were shown to be experimentally susceptible to infection with Neospora caninum, potentially affected by neosporosis, and naturally exposed to the parasite in Asia. Although enzootic to Thailand, the distribution of N. caninum among Thai water buffalo is unclear. The objectives of this study were to determine the seroprevalence of N. caninum among water buffalo of northeast Thailand and to identify risk factors associated with their exposure to N. caninum. Sera from 628 water buffalo from 288 farms were tested with an indirect fluorescent antibody test (IFAT). A total of 57 samples from 48 herds contained antibodies to N. caninum, indicating overall seroprevalence of 9.1% and 16.7% among individual animals and herds, respectively. The overall seroprevalence was highest in provinces located in the Khorat Basin in the southern part of the region tested. Host age was also associated with seroprevalence, with the greatest seroprevalence (16.1%) among buffalo over 10 years of age, followed by 5–10 years of age (13.4%), 3–5 years (9.2%), and less than 3 years (1.2%). These results collectively suggested that horizontal transmission from canine definitive hosts was an important route of water buffalo exposure to N. caninum. These results also verified the importance of risk factor analysis for effective bovine neosporosis control strategies at the local level.