R. K. Mehla

Performance of crossbred calves with dietary supplementation of garlic extract.

Twelve crossbred calves (Holstein cross) in their pre-ruminant stage were used to study the effect of garlic extract feeding on their performance and they were randomly allotted into treatment and control groups in equal number. Performance was evaluated by measuring average body weight (BW) gain, feed intake [dry matter (DM); total digestible nutrient (TDN) and crude protein (CP)], feed conversion efficiency (DM, TDN and CP), fecal score and fecal coliform count. Diets were same for both groups. In addition, treatment group received garlic extract supplementation at 250 mg/kg BW/day/calf. BW measured weekly, feed intake measured twice daily, proximate analysis of feeds and fodders analysed weekly, fecal scores monitored daily and fecal coliform count done weekly. There was a significant (p < 0.01) increase in mean BW gain and feed intake and a significant (p < 0.01) decrease in severity of scours as measured by fecal score in the treatment group compared to the control group. The results suggest that garlic extract can be supplemented to the calves for better performance.

Effect of urea supplemented and urea treated straw based diet on milk urea concentration in crossbred Karan-Fries cows

Abstract The study was undertaken to evaluate the effect of urea supplemented and urea treated straw based diet on milk urea concentration. Six multiparous crossbred Karan-Fries (Holstein Friesian × Tharparkar) cows were blocked into three groups of nearly equal body weight, DIM, milk yield and milk fat content and were randomized into a 3 × 3 Latin square design with 3-week period. Three experimental diets were fed to the animals. Composition of these diets were: Diet 1) green maize, wheat straw and concentrate mixture; Diet 2) green maize, wheat straw, concentrate mixture (urea supplemented) and molasses; Diet 3) green maize (4 % of total DM), 4 % urea treated wheat straw and concentrate mixture. Intake of DM and CP did not vary across the diets. Intake of digestible crude protein (DCP) was found significantly higher in diet 2, while ME and NEl intakes were found significantly lower in diet 3 but did not differ between diets 1 and 2. Average milk and plasma urea concentrations (mg dl-1) were found 29.2 ± 2.6, 45.3 ± 0.9, 34.5 ± 2.3 and 28.9 ± 2.4, 36.6 ± 1.4, 33.9 ± 2.2, respectively in diet 1, diet 2 and diet 3. Urea concentrations in morning milk samples were found significantly lower than noon or evening samples in all the three diets. Concentrations of urea in milk and plasma were found closely correlated (r = 0.94) and the regression equation developed was, plasma urea = 8.90 (.89) + .79 (.02) milk urea. Intake (g) of DCP than CP, per unit (MCal) of ME was found more closely associated with milk urea concentration. The study revealed that urea supplementation and urea treated straw based diet increased urea concentration significantly in milk and plasma. Morning milk urea values that estimated at a time gap of 15 hr since last major feeding may be considered as the lowest level and can be used for interpretation to monitor feeding adequacy or reproductive performances in dairy cows.

Lactation Curve Pattern and Prediction of Milk Production Performance in Crossbred Cows

Data pertaining to 11728 test-day daily milk yields of normal and mastitis Karan Fries cows were collected from the institute herd and divided as mastitis and nonmastitis and parity-wise. The data of lactation curves of the normal and mastitis crossbred cows was analyzed using gamma type function. FTDMY in normal and mastitis cows showed an increasing trend from TD-1 to TD-4 and a gradual decrease (P < 0.01) thereafter until the end of lactation (TD-21) in different parities. The FTDMY was maximum (peak yield) in the fourth parity. Parity-wise lactation curve revealed a decrease in persistency, steeper decline in descending slope (c), and steeper increase in ascending slope (b) from 1st to 5th and above parity. The higher coefficient of determination (R 2) and lower root mean square error (RMSE) indicated goodness and accuracy of the model for the prediction of milk prediction performance under field conditions. Clinical mastitis resulted in a significantly higher loss of milk yield (P < 0.05). The FTDMY was maximum (P < 0.05) in the fourth parity in comparison to the rest of parity. It is demonstrated that gamma type function can give the best fit lactation curve in normal and mastitis infected crossbred cows.

Climatic effects on occurrence of clinical mastitis in different breeds of cows and buffaloes

The study was conducted to find out the effect of different seasons on incidence of mastitis throughout the year in Indigenous cows, crossbred cows and Murrah buffaloes. Lactation records pertaining to the 12 year period were collected and incidence of mastitis was plotted against the climograph of the Karnal zone, Haryana, India. The hot humid climate was found to adversely affect the incidence of mastitis in all the breeds of cows and Murrah buffaloes. The incidence was significantly affected by the season (p<0.01) in all the breeds, however incidence was lowest in Murrah buffaloes in comparison to cows. Further incidence was more in Sahiwal and Tharparkar cows (p<0.01) than the crossbred Karan Swiss and Karan Fries cows. The increase in temperature humidity index resulted in increased incidence of mastitis in cows (p<0.01) but Murrah buffaloes were less affected.

Optimization of Service Period in Karan Fries Cattle Under Sub-tropical Climatic Condition

The primary objective of the study was to determine the optimum length of service period that can maximize the production across the adjacent lactations and life time yield. Performance records of Karan Fries (KF) cow which were maintained at Livestock Research Centre (NDRI), with respect to service period spread over a period of 15 years (1998-2012) were collected for the study. Data of 681 KF cows were analysed by Least Square Technique to examine the effect of non-genetic factors on service period. Season of calving was classified into fourth seasons (i.e. winter, summer, rainy and autumn), period of birth into five periods (i.e. I-V) and parity into six (i.e. I-VI) respectively. For optimization of service period with regard to milk productivity, analysis was carried out by class interval method. Service period was classified into ninth (1-9) classes, ranging from ˂ 51 to >185 days. The overall least square mean of service period was 133.66 ± 3.89 days. Effect of period of birth and parity was significant (P˂0.05) on service period, while season of calving was not significant on service period. The optimum level of service period was obtained at 52-70 days. From the study, it can be concluded that this service period length is suitable for maximising the production in the subsequent lactation.

Optimization of dry period in Karan Fries cow.

Aim: The objective of this study was to optimize dry period (DP) length that can maximize the production across adjacent lactations and overall lifetime yield. Materials and Methods: Performance records with respect to DP spread over a period of 15-year in Karan Fries (KF) cattle maintained at Livestock Research Centre (National Dairy Research Institute), were collected for the study. Data of 681 KF cows were analyzed by least square technique to examine the effect of non-genetic factors on DP. Season of calving was classified into four seasons: Winter season (December-March), summer season (April-June), rainy season (July-September), and autumn season (October-November); period of calving into five periods: 1998-2000 (1-period), 2001-2003 (II-period), 2004-2006 (III-period), 2007-2009 (IV-period), and 2010-2012 (V-period), and parity into six parities, i.e., 1st, 2nd, 3rd, 4th, 5th, and >6th parities to see the effect of non-genetic factors on DP. Results: Period of calving, season of calving, and parity did not affect the DP significantly (p<0.05). The overall least square mean of DP was 67.93±2.12 days. For the optimization of DP with regard to milk productivity, analysis was carried out by class interval method. DP was classified into eight classes (<22, 23-45, 46-67, 68-89, 90-111, 112-133, 134-155, and >156 days), and optimum level was obtained at 46-67 days (3rd class) with the following respective milk yield (MY) of 305 daily MY (4016.44±43.68 kg), total MY (4704.21±61.51 kg), MY per day of lactation length (13.03±0.13 kg), and MY per day of calving interval (11.68±0.41 kg). Conclusion: From the study, it was concluded that this optimal DP length (46-67 days) is suitable for maximizing the production. Hence, one should aim to dry off pregnant cows to achieve a DP of appropriate length to enhance productivity in the next lactation, as very short and very long DP reduces the economic profitability in dairy animals.