Bangladesh Agricultural University Dairy Farm Research Articles

Casein, whey protein and non-protein nitrogen content of milk to identify water, sugar and flour adulterated milk

This study was aimed to assess the potential of using milk's nitrogen distribution pattern, specifically casein, whey protein, and non-protein nitrogen content, as a method for detecting milk adulteration with water, sugar, and flour. Whole milk samples were collected from the Bangladesh Agricultural University Dairy Farm, BAU, Mymensingh, and subjected to adulterations, including 15%, 20%, and 25% water additions and subsequent sugar or flour adjustments to match the fresh milk's specific gravity. The samples were analyzed for specific gravity, fat content, and nitrogen distribution. Results indicated that while specific gravity remained consistent across samples adulterated with sugar or flour, it varied significantly (P<0.05) in those diluted with water. Fat content was significantly (P<0.05) reduced in samples adulterated with water and sugar, particularly at the 25% water addition level. Though total protein, true protein, and casein contents were significantly lower (P<0.05) in the 25% water-added milk compared to fresh milk, they were not significantly different (P>0.05) across the other adulterated samples when compared to fresh milk. Whey protein and non-protein nitrogen levels were statistically consistent (P>0.05) across all the samples. The results indicate that the nitrogen distribution pattern, in its current state, cannot be used to detect milk adulteration effectively. Further research with a larger dataset considering various factors affecting nitrogen distribution in milk is recommended for conclusive results. Bangladesh Journal of Animal Science 53 (1): 23-30, 2024

Effect of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) on shelf life and bacterial population of raw milk

The present study was conducted to assess the feasibility of hydrogen peroxide (H2O2) for milk preservation and also to investigate the effects of H2O2 on growth of bacteria population in milk. Milk samples were collected from Bangladesh Agricultural University dairy farm and preserved with 0.12% H2O2 of 10% concentration on the basis of volume of milk and milk without H2O2 addition treated as control sample. Parameters used to monitor the shelf life of milk were organoleptic and chemical tests. All milk samples were kept in glass container at room temperature (28-31°C) in the laboratory. Organoleptic parameters (color, flavor, texture, taste) and chemical tests (acidity %, COB test and pH) were done every one hour interval until spoilage. Standard Plate Count (SPC) of the samples was done two times, initially and after spoilage of milk. Acidity% increased gradually in all sample but this increase was rapid in control sample than H2O2 treated sample. From COB test it was found that raw milk sample gave positive result at 10th hour but 0.12% H2O2 treated sample (after 20 min of milking ) and 0.12% H2O2 treated sample (after 3 hrs. of milking ) gave positive result 14 and 15th hour respectively. From the result it was observed that shelf life of milk with H2O2 increased. From the SPC result it was found that the bacterial growth rate is very high in control milk sample compare to H2O2 treated milk sample. Significant difference (p<0.01 was found in case of bacterial growth rate of the milk samples. The results of this experiment indicated that H2O2 be used as an effective preservative for prolonging milk preservation. So H2O2 can be used as an effective milk preservative for prolonging milk storage in environmental condition.
 Asian Australas. J. Biosci. Biotechnol. 2021, 6 (1), 19-25

Compositional Changes in Colostrum of Crossbred Dairy Cow

The research was conducted to examine the day-to-day variation in colostrum composition at the udder quarter level. For this purpose, a total of 3 Holstein Frisian crossbred cows were selected from Bangladesh Agricultural University Dairy Farm. Colostrum samples were collected both as mixed and separately from different teats. The concentration of major colostrum constituents (fat, protein, lactose, total solids, solids-not-fat, ash, pH, specific gravity) changed significantly (p≤0.05), the levels on day 4 were found similar to those of normal milk. The highest mean value of fat, protein, total solid, SNF, ash and specific gravity in colostrum was observed on 1st post-partum day as 6.02±0.70, 14.20±0.18, 23.88±1.25, 17.94±0.42, 1.03±0.05% and 1.05±0.00, respectively and later on, decreased as postpartum days advanced. Minimum average fat, protein, total solid, SNF, and ash content in colostrum was observed on 5th postpartum days as 3.75±0.11, 3.24±0.08, 12.00±0.20, 8.27±0.16% and 0.695±0.01, respectively. But lactose percent and pH showed an increasing trend from 1 to 5 postpartum days. Minimum average lactose and pH was observed on 1st and 5th postpartum days as 2.42±0.06%; 6.03±0.04% and 4.26±0.15; 6.30±0.04, respectively. The quality of colostrum produced by udder quarters was found significantly different (p<0.05). The rear quarters produced colostrum, which was significantly richer in fat, proteins, TS, pH compared to forequarters colostrum. The forequarters produced colostrum which was significantly richer in lactose, ash, SNF compared to forequarters colostrum. In conclusion, the results showed that colostrum composition was significantly changed up to 5 days post-partum.

Blood profile of lactating crossbred cows rearing at Bangladesh Agricultural University Dairy Farm

This study aimed to analyze the hemato profile of crossbred lactating cows reared at Bangladesh Agricultural University (BAU) Dairy Farm. Thirty-two (32) healthy crossbred lactating cows of Holstein-Frisian (HF), Jersey (J), Sindhi Sahiwal (SS) and Red Chittagong (RCC) were selected for the study and divided into four (04) groups. The cows were allowed to feed and manage according to dairy farm own scheduled-ration. The collected blood samples were analyzed for hematological and biochemical parameters viz. Hemoglobin (Hb), Packed cell volume (PCV), Total leukocyte count (TLC), and Total erythrocyte count (TEC) and Serum urea, Glucose, Albumin, Calcium, and Phosphorus, respectively by using an automated chemistry analyzer. The results revealed that the hematological and biochemical parameters non-significantly (p>0.05) differed between the crossbred groups. From the experiment, the higher amount of Hb (11 g/dL) and PCV (40%) was found in HF and RCC cows, respectively. The TLC was higher in SS and RCC but the TEC was recorded stable along with a slight increment in RCC. As far as the biochemical parameters are concerned, the blood urea concentration was found higher (28 mg/dL) in HF and RCC lactating cows. The same pattern was observed in the case of albumin concentration. On the contrary, the lowest value of Calcium was found in RCC but the Phosphorus concentration showed a little higher in RCC. It can be concluded that the overall herd health was satisfactory based on the blood profile parameters.
 Bang. J. Anim. Sci. 2019. 48 (2): 139-144

Isolation, molecular identification and antimicrobial resistance patterns of Campylobacter species of dairy origin: first report from Bangladesh

This study was aimed for isolation, identification and characterization of Campylobacter species from Bangladesh Agricultural University (BAU) dairy farm during the period of January to May, 2016. A total of 80 samples (faecal samples of calves, heifers and cows; milk samples of cows) were collected from Bangladesh Agricultural University dairy farm for isolation and identification of Campylobacter species by using cultural, biochemical and molecular methods. Moreover, the isolated Campylobacter species were subjected for antimicrobial susceptibility test. Campylobacter like organisms were presumptively identified in 20 samples. Isolates were biochemically positive to catalase and oxidase tests and in hippurate hydrolysis test some of the isolates (n=6) shown negative that indicated the isolates were C. coli and some of the test isolates (n=14) shown positive that indicated the isolates were C. jejuni. Campylobacter specific 16S rRNA genes were amplified from the isolates. Out of 20 isolated Campylobacter 14 (17.5%) were detected as C. jejuni and the rest 6 (7.5%) were detected as C. coli by cdtC gene based multiplex PCR assay. C. jejuni were resistant to amoxicillin, erythromycin, azithromycin and susceptible to gentamicin, ciprofloxacin, norfloxacin and streptomycin. Furthermore, C. coli were resistant to amoxicillin and erythromycin and susceptible to gentamycin, ciproflaxacin. Out of 20 Campylobacter isolates, 57.14% C. jejuni and 33.33% C. coli were identified as multidrug resistant. To the best of our knowledge, this study has brought the first report on the occurrence of Campylobacter species with their antibiogram profiles in any dairy farm of Bangladesh.

Multi–drug resistant Staphylococcus aureus isolated from milk, chicken meat, beef and egg in Bangladesh

Staphylococcal infection is one of the most common food-borne diseases in the world. Moreover, antimicrobial resistance of pathogenic bacteria, including Staphylococcus (S.) aureus is an emerging problem of food safety. This study was conducted to investigate the prevalence of S. aureus in milk, chicken meat, egg and beef; and to determine the multi-drug resistance (MDR) profile of S. aureus in Mymensingh and Gazipur districts, Bangladesh. A total of 189 samples of milk (n=108), chicken meat (n=51), egg (n=20) and beef (n=10) were collected from Bangladesh Agricultural University dairy farm, American dairy farm, Gazipur and different dairy farms of municipal area and retail shops during July 2016 to June 2018. S. aureus were isolated and identified by conventional methods and polymerase chain reaction (PCR). Antimicrobial susceptibility tests were done through disc diffusion test using 10 commonly used antibiotics. The overall prevalence of S. aureus in all food samples was 43.39%. A total of 39 (76.47%) chicken meat, 25 (23.15%) milk, 11(55%) egg and 07 (70%) beef samples were S. aureus positive through conventional method. Among 82 culture positive samples only 39 samples (47.56%) were confirmed by PCR. Antibiogram study showed that S. aureus isolated from chicken meat were mostly resistant to oxytetracycline (71.79%); and highly sensitive to amikacin (100%) and neomycin (100%). S. aureus isolated from milk samples were highly sensitive to neomycin (100%), and resistant to amikacin (56%). Only 28.57% isolates of S. aureus originated from beef samples were resistant to oxytetracycline and 100 % isolates were sensitive to ciprofloxacin, gentamicin, erythromycin, azithromycin, doxycycline. Similarly, S. aureus isolated from egg samples were resistant to erythromycin (81.82%) and 100% sensitive to amikacin. Out of 41.46% MDR isolates 12%, 53.85%, 90.91% and 0% of the S. aureus originated from milk, chicken meat, egg and beef respectively. The higher prevalence of S. aureus in chicken meat, beef, egg and milk indicates unhygienic production, marketing and processing of these foods. Presence of MDR S. aureus in these foods might pose serious public health threats. Rational use of antibiotics with higher sensitivity should be prescribed in managing poultry diseases to reduce re-emerging MDR in Bangladesh.Res. Agric., Livest. Fish.5(2): 175-183, August 2018

Prevalence of foot diseases in cattle in two dairy farms

The prevalence of claw affections was investigated in 602 cattle in two organized dairy farms during June 2010 to May 2011. Of these cattle 176 were from Bangladesh Agricultural University Dairy Farm (BAUDF) and 426 were from Central Cattle Breeding Station and Dairy Farm (CCBSDF). These animals were studied under 6 groups: calf, heifer, pregnant cow, lactating cow, dry cow and breeding bull. Out of 426 cattle in CCBSDF, 85 animals were affected with various claw affections, the prevalence being 19.95%. The prevalence in BAUDF was 22.72%. Claw affections causing lameness comprised sole ulcer (3.82%), heel erosion (2.49%), interdigital necrobacillosis (2.15%), sand crack (1.82%), hoof overgrowth (3.32%) and white line disease (2.32%). The prevalence of lameness in BAUDF was 13.06% and that in CCBSDF was 11.50%. Sole ulcer (3.82%) was predominantly associated with lameness in both farms while the lowest prevalence of lameness was encountered with interdigital dermatitis (1.39%). The lowest prevalence of lameness was observed in calves in both BAUDF (0.56%) and CCBSDF (0.93%). Pregnant cows were the most vulnerable to claw diseases and manifested lameness of varying degrees. Hind limbs were more frequently affected with claw affections than fore limbs. Animals of over 5 years were mostly affected with foot diseases. Breeding bulls showed 2.27% prevalence of lameness in BAUDF and 1.87% CCBSDF. Among various affections sole ulcer ranked the highest in both the farms. Sand crack and interdigital necrobacillosis registered the lowest prevalence in BAUDF and interdigital dermatitis was the lowest in CCBSDF. Sole ulcer ranked the highest among all claw affections. Pregnant cow were more vulnerable to lameness. Hind limbs were frequently affected with various lesions than the forelimbs.Res. Agric. Livest. Fish.4(3): 193-199, December 2017

Evaluation of morning and evening milk of Holstein Friesian crossbred cows collected from Bangladesh Agricultural University Dairy Farm

The present study was undertaken to evaluate the organoleptic, specific gravity, chemical and microbiological qualities of morning and evening milk which collected from Bangladesh Agricultural University Dairy Farm, Mymensingh. In this purposes, six Holstein Friesian crossbred cows were selected for this study. Milk samples were collected every morning and evening immediately after milking and then subjected to test all mentioning parameters. Morning milk showed less yellowish than evening milk whereas flavor, body and texture were found normal in both intervals of milk. Specific gravity was found higher (1.030 ±0.000) in morning milk than evening and significantly (p<0.01) higher fat content observed in evening milk sample due to the more exercise the whole day. Again, total solids, solids-not-fat, protein and lactose content of milk showed significant difference at p<0.05. Other parameters like acidity percent and ash did not show any significant difference. Significantly (p<0.05) higher coliform count was noticed in morning milk than evening milk and non-significant (p>0.05) difference found in total viable count of both intervals milk. Considering the research findings, it might be said that evening milk was better than morning milk. Asian Australas. J. Biosci. Biotechnol. 2016, 1 (2), 255-260

Evaluate comparative efficacy of tuberculin test, gross and histopathology, Ziehl-Neelsen staining and polymerase chain reaction technique for the detection of tuberculosis in dairy cattle

Tuberculosis (TB) is an archaic infectious disease of human and animals caused by Mycobacterium spp and responsible for considerable morbidity and mortality. TB in man and animals is mostly caused by Mycobacterium bovis (M. bovis, bovine TB) and Mycobacterium tuberculosis (M. tuberculosis, human TB). This study, was, aimed at rapid and specific identification of bovine TB and human TB in dairy cattle by using intradermal tuberculin test, gross and microscopic pathology, Ziehl-Neelson staining of tissue sections and PCR detection of the specific causes of TB. Out of 100 dairy cattle tested using intradermal tuberculin test in the Bangladesh Agricultural University dairy farm during the period between 2013 and 2014, 05 yielded hypersensitivity reactions to intradermal tuberculin test. The tuberculin test positive cattle (N=5) were sacrificed and investigated systematically. Gross lesions observed were recorded during necropsy and lungs, liver, spleen, kidney and lymphnodes were collected in 10% buffered neutral formalin for histopathological examination. A small portion of lungs were snap frozen and preserved at -20 0 C for the extraction of genomic DNA and PCR detection of TB. Grossly nodular masses in lungs and enlarged mesenteric lymphnodes were observed in four cases. Accumulation of macrophages, lymphocytes and fibrous connective tissue was seen in microscopic section of lungs, spleen and lymphnodes. Tissue sections stained with Ziehl Neelsen staining, showed rod shaped bright red color acid fast bacilli in three cattle. The multiplex PCR used successfully amplified fragment of 16srRNA gene specific for Mycobacterial infections (1030bp) and infection due to Mycobacterium tuberculosis complex (372bp) in four cases. Results of uniplex PCR showed that three cattle were infected with M. bovis (MPB83 gene specific 600bp amplicon) and one cattle with M. tuberculosis (H37Rv Rv3479HP gene specific 667bp amplicon). Out of five tuberculin test positive cattle sacrificed in this study, four were found to infect with TB; one cattle could have reacted due to infection with saprophytic mycobacterium or other infections that cross reacted to tuberculin test. The multiplex and uniplex PCR adapted and designed in this study found sensitive, accurate and conclusive. Dairy cattle in this farm were infected with M. bovis and M. tuberculosis. M. bovis and M. tuberculosis are extremely zoonotic pathogens. It needs to examine all of the dairy cattle with tuberculin test and PCR test twice in a year, sacrifice the test positive cattle at early onset to prevent dissemination in farm animals and human. People working in the farms also need to sit for tuberculin test, Ziehl Neelsen staining and PCR test of cough to detect infected and carrier state of infection.

Evaluation of reproductive health status in government and commercial dairy herds of Bangladesh

To evaluate the reproductive herd health status, the data were collected from Talbag Dairy Farm, Savar; Bangladesh Agricultural University Dairy Farm, Mymensingh and Central Cattle Breeding and Dairy Farm, Savar for a period of two years. A total of 122 lactating cows were selected to collect data on productive and reproductive performance from the farms record book maintained by three farms. The mean value ± SD of breeding age, calving age, age at first conception, calving to first estrus, calving to first service, days open, calving interval, first service conception rate, number of service per conception, calf per year of Talbag Dairy Farm, BAU Dairy Farm, Central Cattle Breeding and Dairy Farm were 25.10 ± 2.68, 219.23 ± 12.23 and 27.40 ± 7.56 months; 34.30 ± 8.54, 55.88 ± 11.60 and 38.93 ± 8.58 months; 26.20 ± 4.05, 52.71 ± 12.55 and 29.83 ± 8.72 months; 165.00 ±73.82, 219.23 ± 121.83 and 190.50 ± 104.19 days; 165.00 ±73.82, 240.77 ± 128.59 and 190.50 ± 104.19 days; 201.00 ± 72.48, 250.38 ± 72.82 and 335.08 ± 118.61 days; 383.30 ± 57.87, 526.44 ± 196.80 and 523.17 ± 216.37 days; 73.50 ± 29.25, 64.75 ± 30.53 and 61.85 ± 31.87 %; 1.95 ± 0.44, 1.99 ± 0.72 and 2.30 ± 1.02; 383.30 ±57.87, 526.44 ± 196.80 and 523.17 ± 216.37 days, respectively. The overall calf mortality (%) in Talbag Dairy Farm, BAU Dairy Farm, Central Cattle Breeding and Dairy Farm were 4%, 0.70% and 4.06%, respectively. The calf mortality (%) at birth and birth to 30 days in Talbag Dairy Farm, BAU Dairy Farm, Central Cattle Breeding and Dairy Farm were 3%, 1% and 1.85%; 3.5%, 5% and 6.39%; respectively. It is concluded that commercial farms reasonably better due to optimum level of breeding age, first service conception rate, less calving interval and less service per conception.Asian J. Med. Biol. Res. June 2015, 1(1): 31-38

Isolation and characterization of Staphylococcus aureus from raw cow milk in Bangladesh

The study was intended for identification and characterization of Staphylococcus aureus isolated from raw cow milk. A total of 47 milk samples were collected from Sheshmore, Shutiakhali and Bangladesh Agricultural University Dairy Farm, Mymensingh. Using bacteriological, biochemical and PCR-based identification schemes, 12 (25.53%) isolates were confirmed as S. aureus. All the isolates showed β-hemolysis on 5% sheep blood agar. S. aureus specific nuc gene (target size 279-bp) was amplified in the cases of all isolates. The isolates were found as resistant to Penicillin (100%), Erythromycin (75%) and Amoxicillin (100%). On the other hand, the isolates were sensitive to Ciprofloxacin (83.33%), Oxacillin (100%), Cloxacillin (100%) and Neomycin (100%). The isolated S. aureus showed increased resistance to broad spectrum antibiotic (e.g., Ciprofloxacin). As many people have a tendency to drink raw milk and raw milk products, there is high risk of S. aureus infection in human.

Prevalence of sub-clinical mastitis in dairy farms

A total of 560 lactating cows belonging to Bangladesh Agricultural University dairy farm (n = 59): Local Zebu (L), Local × Friesian (L × F), Local × Jersey (L × J), Local × Red Chittagong Cattle (L × RCC), Local × Sahiwal (L × SL), Red Chittagong Cattle (RCC); and Central Cattle Breeding Station and Dairy Farm (n = 501): Local Zebu, L × F, SL × F, Sahiwal and Australian Friesian Sahiwal (AFS) were selected to measure prevalence of subclinical mastitis (SM). The California Mastitis Test was done and the prevalence of SM was 68% on cow basis and 57% on quarter basis. The prevalence rate was significantly higher in L × F (87%, P < 0.05), SL × F (88%, P < 0.05), L × J (100%, P < 0.01), AFS (89%, P< 0.05) and SL (100%, P < 0.01). The local Zebu (31%) and RCC (28%) were least susceptible to SM. SM was significantly higher in multiparous (P < 0.05) and older cows (P < 0.05). The front quarters were more prone to SM than the rear. Factors such as breed, age, parity and management may have been responsible for high prevalence of SM in both farms. DOI: http://dx.doi.org/10.3329/bvet.v30i2.18257 Bangl. vet. 2013. Vol. 30, No. 2, 70-77

Estimation of effect of breeding bulls and genetic parameters on early growth performance of calves at farm and field levels

The present study was conducted using records on four breeding bulls maintained at the Artificial Insemination (AI) Center of Bangladesh Agricultural University (BAU), Mymensingh and on 154 of their progeny maintained at BAU Dairy Farm (112) and some villages (42 progeny) adjacent to BAU for estimating the effect of breeding bulls and genetic parameters on early growth performance of the progeny at farm and field levels. Genetic correlations between traits of bulls and their progeny were also estimated. Bull traits were metabolic body weight (MWT), feed intake (FI) and residual feed intake (RFI) where progeny traits were birth weight (BWT), final body weight (FWT) at 90 days of age and average daily gain (ADG). Mean BWT of progeny at farm and field level was 16.34±1.85 to 17.62±1.97 kg and 13.89±2.78 to 16.11±2.98 kg, respectively. The FWT at farm progeny was 48.9±2.87 to 55.67±2.14 kg whereas 43.43±2.50 to 52.22±3.34 kg for field progeny. The ADG at farm and field progeny was 0.36±0.03 to 0.43±0.01 and 0.32±0.03 to 0.42±0.03 kg, respectively. The BWT and FWT of farm progeny were significantly (p>0.05) higher than the progeny of field level. Breeding bulls had significant (p<0.05) effect on FWT and ADG for both of the farm and field progeny. Estimated heritability was found to be moderate in case of BWT (0.32±0.19), but low for FWT (0.26±0.18) and ADG (0.29±0.20) for pooled average. The genetic correlation between bulls’ MWT and BWT was high (rg=0.54±0.17), but low with FWT(rg=0.26±0.18) and ADG (rg=0.28±0.23). Moderate in daily FI of bulls was genetically correlated with BWT (0.45±0.22), FWT (0.38±0.24) and ADG (0.35±0.25) for their progeny, while low but favorable negative genetic correlation (rg=-0.13±0.17) was observed between ADG of progeny and RFI of bulls. The negative correlation for RFI with ADG suggested that selection might result in better success in improving herd production efficiency without compromising progeny growth performance. DOI: http://dx.doi.org/10.3329/bjas.v42i2.18484 Bang. J. Anim. Sci. 2013. 42 (2): 81-88

Effect of supplementation of fish meal on growth and reproductive performance of crossbred heifers

The experiment was conducted at Bangladesh Agricultural University Dairy Farm to study the effect of fish meal (FM) on growth and reproductive performances of crossbred heifers. The experiment was designed into four treatment (T0=0% FM; T1=5% FM; T2=7.5% FM and T3 =10% FM) groups having initial weight 231.33 ± 32.39, 241.00 ± 46.29, 198.66 ±58.53 and 236.66 ± 31.64 kg, respectively. The average age of the animal is 2 years 9 month. Results of the experiment revealed that there was a significant difference of FM on daily DMI (kg/d). In 90 days period, FM with rice straw based diet had significant effect on daily weight gain (kg/d) of crossbred heifers. DM, CP and CF digestibility (%) differ significantly (p<0.05) among the group. But, the EE, Ash and NFE do not differ significantly. However, there is a tendency to increase digestibility when increase the FM among the Treatment group. Among this group T3 and T1 treatment showed 100% and T0 treatment 66% estrus and T1 did not showed estrus. Based on above findings, it may be concluded that supplementation of FM with Rice straw based diet can be the best options for feeding crossbred heifers to obtain better performances in terms of dry matter intake, digestibility, daily weight gain and reproductive performance especially estrus.DOI: http://dx.doi.org/10.3329/jbau.v10i2.14917 J. Bangladesh Agril. Univ. 10(2): 261-266, 2012

PREVALENCE OF SUBCLINICAL MASTITIS IN DAIRY COWS IN SELECTED AREAS OF BANGLADESH

This research was carried out to determine the prevalence of subclinical mastitis in lactating Dairy Cow of Bangladesh Agricultural University dairy farm (BAUDF) and rural areas of Tangail sadar upazila of Bangladesh during the period of July 2009 to April 2010. A total of 200 milk samples (40 from BAUDF and 160 from Tangail sadar upazila) were collected for this study which were subjected to physical examination and subsequently screened for subclinical mastitis using three indirect tests viz. White Side Test (WST), California Mastitis Test (CMT), and Surf Field Mastitis Test (SFMT). Overall prevalence of subclinical mastitis (SCM) in lactating dairy cows found in this study was 29%. Cows were infected with SCM 29.5%, 27.5% and 25.5% detection by CMT, WST and SFMT respectively. Higher prevalence of SCM was detected in milch crossbred cows (36.36%) in comparison to local bred cows (24.61%) maintained under extensive management system in Rural area of Tangail sadar upazila. The prevalence of SCM was recorded in 31.58%, 30.76% and 68.75% in cows of local area of Tangail sadar upazila, and 25.0%, 40.0% and 71.42% in cows of BAU,DF during the early, mid and late stages of lactation respectively. The highest prevalence of SCM was recorded during the early lactation stage in both the local breed cows (30.0%) and cows of BAUDF (45.83%) in comparison to their respective mid and late stages of lactation. The prevalence of SCM was highest in lactating cows having third lactation and high yielding (cows produced >10 liter milk per day) both in local breed and crossbred cows.DOI = http://dx.doi.org/10.3329/bjvm.v9i1.11216 Bangl. J. Vet. Med. (2011). 9(1): 73-78

Reproductive Problems of Cows at Bangladesh Agricultural University Dairy Farm and Possible Remedies

Reproductive Problems of Cows at Bangladesh Agricultural University Dairy Farm and Possible Remedies

Comparative Study on the Productive and Reproductive Performance of Different Dairy Genotypes Reared in Bangladesh Agricultural University Dairy Farm

The study was conducted at Bangladesh Agricultural University Dairy Farm for a period of six months. A total of 164 dairy cows belongs to different breeds, such as Jersey cross, Sahiwal cross, Sindhi cross, Holstein cross and Red Chittagong cows were selected and their information regarding milk production and other reproductive parameters were collected from farm records for a period of last five years (1993-1997). The number of animals of each of the genotypic classes were 48 for Jersey cross, 46 for Sahiwal cross, 35 for Sindhi cross, 20 for Holstein cross and 15 for Red-Chittagong. Significant difference was found within the milk yield (p 0.05). Highest milk yield (3.20 lit/day), highest birth weight of calves (15.2 kg) and lowest calving interval (414 days) were observed for Holstein cross. The lowest milk yield (2.46 lit/day) and lowest birth weight of calves were found in Red-Chittagong cows. Production performance of Holstein crossbred were superior to other dairy crossbreds. Jersey crossbred ranked second and performances of other genotypes were nearly similar.

Prevalence of Brucella antibodies in sera of cows in Bangladesh

The study was carried out to investigate the prevalence of Brucella antibodies in sera of 120 cows in Bangladesh Agricultural University Dairy Farm and adjacent villages, Bangladesh. The epidemiological history and blood was collected from the cows. The serum samples were subjected to Rose Bengal Test (RBT) and plate agglutination test (PAT) for initial screening of Brucella antibodies and the positive sera samples were then subjected to tube agglutination test (TAT) for further confirmation. The higher rate of Brucella antibody was recorded in rural farm (5.0%) than organized farm (2.5%) and in pregnant cows (5.9%) than non-pregnant cows (4.7%). A total of 3(4%) Brucella positive antibody cases were recorded in cows of above four years of age whereas, 1(2.3%) positive case was found in cows of less than 4 years of age. The study revealed that number of Red Shindi was the highest and the prevalence of brucellosis in Bangladesh cow population is not negligible and it is worthwhile to consider adoption of preventive measures.

Physical and microbial qualities of raw milk collected from Bangladesh Agricultural University dairy farm and the surrounding villages

The present study was undertaken with the aim of investigating the physical parameters (e.g. organoleptic and specific gravity of raw milk) and also to study the microbiological quality of raw milk (total viable count, Coliform count and Staphylococcal count) from different villages and Bangladesh Agricultural University (BAU) Dairy Farm of Mymensingh District of Bangladesh, during the period from July to November 2007. A total number of 100 raw milk samples were collected at morning and evening from BAU dairy farm and surrounding four villages of BAU campus. The organoleptic and bacteriological qualities of each sample were analyzed. The organoleptic examination included taste panel score to assess consumer's acceptance and the bacteriological analysis comprised enumeration of total viable count (TVC), total colifrom count (TCC) and total staphylococcal count (TSC) for the determination of sanitary quality. The organoleptic quality of the milk samples is more or less same except the Churkhai milk samples which had flat taste (in 16% milk sample). The average values of TVC/ml were log 5.920, 5.934, 6.007, 6.075 and 6.127 for BAU Dairy Farm, Boira, Shutiakhali, Churkahai and Paglabazar respectively; coliform count were log 2.501, 2.522, 2.550, 2.620 and 2.619 respectively; staphylococcal count were log 2.832, 2.812, 2.866, 2.931 and 2.988 respectively. So, it may be concluded that the raw milk samples of BAU Dairy Farm were superior to others collected from the selected villages which may be due to maintaining better hygienic condition. Key words: Raw milk, physical and microbial quality  doi: 10.3329/bjvm.v6i2.2339 Bangl. J. Vet. Med. (2008). 6 (2): 217-221

HOST DETERMINANTS BASED COMPARATIVE PREVALENCE OF SUBCLINICAL MASTITIS IN LACTATING HOLSTEIN-FRIESIAN CROSS COWS AND RED CHITTAGONG COWS IN BANGLADESH

A comparative prevalence of sub-clinical mastitis (SCM) based on host risk factors was studied by using California Mastitis Test (CMT) in 96 Holstein-Friesian cross cows (HFCC) of Abu Baker Dairy Farm at Pansha Upazilla in Rajbari district and 20 Red Chittagong cows (RCC) of Bangladesh Agricultural University Dairy Farm (BAUDF), Mymensingh during the period from January to June 2008. Out of the 116 lactating cows examined, 51 (43.97%) showed positive reactivity to CMT. Similar prevalence rate of SCM was recorded in both the HFCC (43.75%) and RCC (45.0%). The overall prevalence of SCM on the basis of lactation stages showed that all the three lactation stages had SCM but there was a tendency to increase its prevalence rates from early (30.43%), mid (32.26%) to late (69.23%) stages. The highest prevalence of SCM was recorded at late lactation stage in both the HFCC (68.75%) and RCC (71.43%) in comparison to their respective mid and early lactation stages. The parity-wise prevalence of SCM was recorded as 18.42%, 55.0%, 66.67%, 75.0% and 75.0% in HFCC whereas, it was 20.0%, 20.0%, 66.67%, 75.0% and 66.67% in RCC at their 1st, 2nd, 3rd, 4th and 5th parity, respectively. This study recorded a relationship between the increased prevalence of SCM with decreased of milk production in both the groups of lactating cows. The respective prevalence of SCM at high, medium and low level of milk production in HFC (14.29%, 33.33% and 70.59%) and RCC (14.29%, 50.00% and 71.42%) were found significantly (p < 0.01) correlated with milk production. An overall 19.18% quarters was affected with SCM, of which 4.31%, 7.33% and 7.38% showed mild, moderate and severe reaction to CMT. However, comparatively, higher percentage of quarter infection was recorded in HFCC (20.31%) than RCC (13.75%). It may be concluded from these observations that both the HFCC and RCC should be monitored by using CMT for the detection of SCM in order to provide rational treatment and control it to make the dairy farming profitable. DOI = 10.3329/bjvm.v8i1.7397 Bangl. J. Vet. Med. (2010). 8(1): 17-21