Pravinkumar Chaudhari | Junagadh Agricultural University, Junagadh (original) (raw)

Papers by Pravinkumar Chaudhari

International Journal of Livestock Research, 2022

Lactation milk yield in dairy bovines is closely related with, and therefore a function of, peak ... more Lactation milk yield in dairy bovines is closely related with, and therefore a function of, peak yield, persistency and lactation length. Therefore, characteristics, curve, and persistency of lactation were studied in Jaffarabadi (Bubalus bubalis) buffaloes. A total of 1,15,339 daily morning and evening milk production performance records in 176 lactations of 1 st to 6 th parity of 30 Jaffarabadi buffaloes lactating at the Cattle Breeding Farm, JAU, Junagadh, Gujarat over a period of 28 years (1991-2018) were used for the study. Overall lactation length (LL), total lactation milk yield (TLMY), and standard lactation milk yield (SLMY) of the Jaffarabadi buffalo averaged 325.90 ± 5.53 days, 2009.31 ± 42.13 lit and 1872.61 ± 32.88 lit, respectively. Overall daily peak yield (DPY) was 11.27 ± 0.20 lit/day, attained at 102.00 ± 4.68 days postpartum. Overall weekly peak yield (WPY) and weeks to attain WPY averaged 64.79 ± 1.09 lit/week and 13.72 ± 0.64 weeks, respectively. Weekly milk yield could be predicted using linear function [(ŷ = 59.149 + (-0.6634) × X)] and logarithmic function [(ŷ = 1.80 × (-0.0008)^X)] with an accuracy of 66 to 73%. In contrast, monthly milk yield could be predicted using linear function [(ŷ = 261.64 + (-13.229) × X)] and logarithmic function [(ŷ = 2.45 × (-0.035)^X)] with comparatively more precision, R 2 value being 79.7 to 81.2 %. Overall persistency in terms of weekly and monthly milk yield was estimated to be 98.03±0.24% and 91.24±0.59%, respectively.

The Pharma Innovation Journal, 2022

The present study was carried out using data of first lactation records of 513 Gir cows sired by ... more The present study was carried out using data of first lactation records of 513 Gir cows sired by 75 bulls spread over a period of 34 years (1981 to 2014), maintained at Cattle Breeding Farm, Junagadh Agricultural University, Junagadh. Analysis was carried out by least squares analysis method described by Harvey (1966). The overall least squares means for first lactation monthly test day milk yield (FLMTMY) varied from 3.39 + 0.17 kg (FLMTMY10) to 6.40 + 0.15 kg (FLMTMY3). Only FLMTMY3 (peak yield phase) was influenced significantly (P<0.05) due to variation of season of calving. The period of calving had highly significant (P<0.01) effect on all MTDMY. The AFC had significant (P<0.05) effect on FLMTMY1, FLMTMY2 and MTMDY5. However, calf birth weight had highly significant (P<0.01) effect on FLMTMY1 and FLMTMY2 while its effect was significant (P<0.05) on FLMTMY4.

International Journal of Livestock Research, 2022

Lactation milk yield in dairy bovines is closely related with peak yield, persistency and lactati... more Lactation milk yield in dairy bovines is closely related with peak yield, persistency and lactation length. Therefore, characteristics, curve and persistency of lactation were studied in Gir cows. A total of 2,24,748 morning and evening milk production records of 300 lactations of 1-6 parity Gir cows present at Cattle Breeding Farm, JAU, Junagadh, Gujarat over a period of 31 years (1986-2016) were used for this study. Overall lactation length (LL), total lactation milk yield (TLMY) and standard lactation milk yield (SLMY) of the Gir cows averaged 371.59±5.42 days, 2674.21±48.79 lit and 2380.79±37.68 lit, respectively. Overall daily peak yield (DPY) was 13.25±0.17 lit/day, attained at 48.47±2.40 days postpartum. Overall weekly peak yield (WPY) and weeks to attain WPY averaged 82.08±1.11 lit/week and 6.54±0.31 weeks, respectively. Weekly milk yield could be predicted using linear function [(y =79.5139+(-1.1002×X)] and logarithmic function [(y =1.9378× (-0.00965) ^X)] with an accuracy of 86 to 95%, while monthly milk yield could be predicted using linear function [(y =348.52+(-20.26×X)] and logarithmic function [(y =2.588× (-0.042) ^X)] with comparatively higher R2 value of 94.01 to 98.05%. Overall persistency, in terms of weekly and monthly milk yield was estimated to be 96.82±0.13% and 88.77±0.37%, respectively.

Indian Journal of Veterinary Science and Biotechnology, Apr 10, 2022

Lactation milk yield in dairy bovines is closely related with, and therefore a function of, peak ... more Lactation milk yield in dairy bovines is closely related with, and therefore a function of, peak yield, persistency and lactation length. Therefore, characteristics, curve, and persistency of lactation were studied in Jaffarabadi (Bubalus bubalis) buffaloes. A total of 1,15,339 daily morning and evening milk production performance records in 176 lactations of 1 st to 6 th parity of 30 Jaffarabadi buffaloes lactating at the Cattle Breeding Farm, JAU, Junagadh, Gujarat over a period of 28 years (1991-2018) were used for the study. Overall lactation length (LL), total lactation milk yield (TLMY), and standard lactation milk yield (SLMY) of the Jaffarabadi buffalo averaged 325.90 ± 5.53 days, 2009.31 ± 42.13 lit and 1872.61 ± 32.88 lit, respectively. Overall daily peak yield (DPY) was 11.27 ± 0.20 lit/day, attained at 102.00 ± 4.68 days postpartum. Overall weekly peak yield (WPY) and weeks to attain WPY averaged 64.79 ± 1.09 lit/week and 13.72 ± 0.64 weeks, respectively. Weekly milk yield could be predicted using linear function [(ŷ = 59.149 + (-0.6634) × X)] and logarithmic function [(ŷ = 1.80 × (-0.0008)^X)] with an accuracy of 66 to 73%. In contrast, monthly milk yield could be predicted using linear function [(ŷ = 261.64 + (-13.229) × X)] and logarithmic function [(ŷ = 2.45 × (-0.035)^X)] with comparatively more precision, R 2 value being 79.7 to 81.2 %. Overall persistency in terms of weekly and monthly milk yield was estimated to be 98.03±0.24% and 91.24±0.59%, respectively.

Indian Journal of Veterinary Science and Biotechnology, 2022

In the field condition, various milk recording options or test-day recording can be a useful tool... more In the field condition, various milk recording options or test-day recording can be a useful tool to approximate/predict the production potential of field bovines. Therefore, a study was carried out to approximate/predict standard lactation milk yield in Gir (Bos indicus) cows from different milk recording options and test-day milk yield. A total of 2,24,748 daily morning and evening milk production performance records in 300 lactations of 50 Gir cows lactating at the Cattle Breeding Farm, JAU, Junagadh (Gujarat) over a period of 31 years (1986-2016) were used for the study. Test day records, 125, 155 , and 185 th at mid-and late lactations, i.e., 4, 5, and 6 th month, alone or combining consecutive two or three variables and even test day records 155 th to 275 th , i.e., from 5 th to 9 th month along with daily peak yield were found important in determining the SLMY. Sum-up of morning and evening milk yield at weekly intervals till the cow dries could be used to estimate lactation milk yield by the equation 0.59+6.97×Sum or sum-up of morning and evening milk yield records at the fortnightly interval by the equation 21.23+14.73×Sum, with a precision of 99%.

Indian Journal of Dairy Science, 2015

First lactation monthly test day records of 2329 buffaloes sired by 79 sires distributed in 47 vi... more First lactation monthly test day records of 2329 buffaloes sired by 79 sires distributed in 47 villages under field progeny testing programme in anand milk shed were used to evaluate sires for age at first calving (AFC), first lactation predicted milk yield (FLY305) and milk fat percent (fat%) traits. The objective of the study was to estimate the sire breeding value and to compare various methods of sire evaluation viz.simple daughter's average (D) , contemporary comparison (CC), least squares (LS), best linear unbiased prediction (BLUP) and average information restricted maximum likelihood (AIREML) in terms of accuracy and efficiency. Heritability estimates by Least Square-Analysis of Variance (LS-ANOVA) method were 0.252 ± 0.044, 0.065 ± 0.032 and 0.073 ± 0.035, respectively for AFC, FMY305 and Fat%. The genetic correlation of AFC with FLY305 and Fat% were-0.782 ± 0.192 and-0.451, respectively while the same between FLY305 and fat percent was 1.044 ± 0.39. The phenotypic correlations of FLY305 with Fat % and AFC were-0.042 and 0.109, respectively while same between Fat % and AFC was-0.099. For AFC, the AIREML had the lowest error variance than LS and BLUP, thus was the most efficient method. For FMY305 and Fat%, the BLUP was found to have lowest error variance and therefore, was the most efficient method. The relative accuracies in terms of rank correlations of D, CC, LS and BLUP methods with most efficient AIREML method were 0.35, 0.90, 0.37 and 0.97, respectively for AFC. For FLY305, the value of rank correlations of D, CC, LS and AIREML with most efficient BLUP method were 0.71, 0.71, 0.72 and 0.98, respectively. The value of rank correlations of D, CC, LS and AIREML with most efficient BLUP method were 0.89, 0.89, 0.95 and 0.99, respectively.

International Journal of Livestock Research, 2022

Lactation milk yield in dairy bovines is closely related with, and therefore a function of, peak ... more Lactation milk yield in dairy bovines is closely related with, and therefore a function of, peak yield, persistency and lactation length. Therefore, characteristics, curve, and persistency of lactation were studied in Jaffarabadi (Bubalus bubalis) buffaloes. A total of 1,15,339 daily morning and evening milk production performance records in 176 lactations of 1 st to 6 th parity of 30 Jaffarabadi buffaloes lactating at the Cattle Breeding Farm, JAU, Junagadh, Gujarat over a period of 28 years (1991-2018) were used for the study. Overall lactation length (LL), total lactation milk yield (TLMY), and standard lactation milk yield (SLMY) of the Jaffarabadi buffalo averaged 325.90 ± 5.53 days, 2009.31 ± 42.13 lit and 1872.61 ± 32.88 lit, respectively. Overall daily peak yield (DPY) was 11.27 ± 0.20 lit/day, attained at 102.00 ± 4.68 days postpartum. Overall weekly peak yield (WPY) and weeks to attain WPY averaged 64.79 ± 1.09 lit/week and 13.72 ± 0.64 weeks, respectively. Weekly milk yield could be predicted using linear function [(ŷ = 59.149 + (-0.6634) × X)] and logarithmic function [(ŷ = 1.80 × (-0.0008)^X)] with an accuracy of 66 to 73%. In contrast, monthly milk yield could be predicted using linear function [(ŷ = 261.64 + (-13.229) × X)] and logarithmic function [(ŷ = 2.45 × (-0.035)^X)] with comparatively more precision, R 2 value being 79.7 to 81.2 %. Overall persistency in terms of weekly and monthly milk yield was estimated to be 98.03±0.24% and 91.24±0.59%, respectively.

The Pharma Innovation Journal, 2022

The present study was carried out using data of first lactation records of 513 Gir cows sired by ... more The present study was carried out using data of first lactation records of 513 Gir cows sired by 75 bulls spread over a period of 34 years (1981 to 2014), maintained at Cattle Breeding Farm, Junagadh Agricultural University, Junagadh. Analysis was carried out by least squares analysis method described by Harvey (1966). The overall least squares means for first lactation monthly test day milk yield (FLMTMY) varied from 3.39 + 0.17 kg (FLMTMY10) to 6.40 + 0.15 kg (FLMTMY3). Only FLMTMY3 (peak yield phase) was influenced significantly (P<0.05) due to variation of season of calving. The period of calving had highly significant (P<0.01) effect on all MTDMY. The AFC had significant (P<0.05) effect on FLMTMY1, FLMTMY2 and MTMDY5. However, calf birth weight had highly significant (P<0.01) effect on FLMTMY1 and FLMTMY2 while its effect was significant (P<0.05) on FLMTMY4.

International Journal of Livestock Research, 2022

Lactation milk yield in dairy bovines is closely related with peak yield, persistency and lactati... more Lactation milk yield in dairy bovines is closely related with peak yield, persistency and lactation length. Therefore, characteristics, curve and persistency of lactation were studied in Gir cows. A total of 2,24,748 morning and evening milk production records of 300 lactations of 1-6 parity Gir cows present at Cattle Breeding Farm, JAU, Junagadh, Gujarat over a period of 31 years (1986-2016) were used for this study. Overall lactation length (LL), total lactation milk yield (TLMY) and standard lactation milk yield (SLMY) of the Gir cows averaged 371.59±5.42 days, 2674.21±48.79 lit and 2380.79±37.68 lit, respectively. Overall daily peak yield (DPY) was 13.25±0.17 lit/day, attained at 48.47±2.40 days postpartum. Overall weekly peak yield (WPY) and weeks to attain WPY averaged 82.08±1.11 lit/week and 6.54±0.31 weeks, respectively. Weekly milk yield could be predicted using linear function [(y =79.5139+(-1.1002×X)] and logarithmic function [(y =1.9378× (-0.00965) ^X)] with an accuracy of 86 to 95%, while monthly milk yield could be predicted using linear function [(y =348.52+(-20.26×X)] and logarithmic function [(y =2.588× (-0.042) ^X)] with comparatively higher R2 value of 94.01 to 98.05%. Overall persistency, in terms of weekly and monthly milk yield was estimated to be 96.82±0.13% and 88.77±0.37%, respectively.

Indian Journal of Veterinary Science and Biotechnology, Apr 10, 2022

Lactation milk yield in dairy bovines is closely related with, and therefore a function of, peak ... more Lactation milk yield in dairy bovines is closely related with, and therefore a function of, peak yield, persistency and lactation length. Therefore, characteristics, curve, and persistency of lactation were studied in Jaffarabadi (Bubalus bubalis) buffaloes. A total of 1,15,339 daily morning and evening milk production performance records in 176 lactations of 1 st to 6 th parity of 30 Jaffarabadi buffaloes lactating at the Cattle Breeding Farm, JAU, Junagadh, Gujarat over a period of 28 years (1991-2018) were used for the study. Overall lactation length (LL), total lactation milk yield (TLMY), and standard lactation milk yield (SLMY) of the Jaffarabadi buffalo averaged 325.90 ± 5.53 days, 2009.31 ± 42.13 lit and 1872.61 ± 32.88 lit, respectively. Overall daily peak yield (DPY) was 11.27 ± 0.20 lit/day, attained at 102.00 ± 4.68 days postpartum. Overall weekly peak yield (WPY) and weeks to attain WPY averaged 64.79 ± 1.09 lit/week and 13.72 ± 0.64 weeks, respectively. Weekly milk yield could be predicted using linear function [(ŷ = 59.149 + (-0.6634) × X)] and logarithmic function [(ŷ = 1.80 × (-0.0008)^X)] with an accuracy of 66 to 73%. In contrast, monthly milk yield could be predicted using linear function [(ŷ = 261.64 + (-13.229) × X)] and logarithmic function [(ŷ = 2.45 × (-0.035)^X)] with comparatively more precision, R 2 value being 79.7 to 81.2 %. Overall persistency in terms of weekly and monthly milk yield was estimated to be 98.03±0.24% and 91.24±0.59%, respectively.

Indian Journal of Veterinary Science and Biotechnology, 2022

In the field condition, various milk recording options or test-day recording can be a useful tool... more In the field condition, various milk recording options or test-day recording can be a useful tool to approximate/predict the production potential of field bovines. Therefore, a study was carried out to approximate/predict standard lactation milk yield in Gir (Bos indicus) cows from different milk recording options and test-day milk yield. A total of 2,24,748 daily morning and evening milk production performance records in 300 lactations of 50 Gir cows lactating at the Cattle Breeding Farm, JAU, Junagadh (Gujarat) over a period of 31 years (1986-2016) were used for the study. Test day records, 125, 155 , and 185 th at mid-and late lactations, i.e., 4, 5, and 6 th month, alone or combining consecutive two or three variables and even test day records 155 th to 275 th , i.e., from 5 th to 9 th month along with daily peak yield were found important in determining the SLMY. Sum-up of morning and evening milk yield at weekly intervals till the cow dries could be used to estimate lactation milk yield by the equation 0.59+6.97×Sum or sum-up of morning and evening milk yield records at the fortnightly interval by the equation 21.23+14.73×Sum, with a precision of 99%.

Indian Journal of Dairy Science, 2015

First lactation monthly test day records of 2329 buffaloes sired by 79 sires distributed in 47 vi... more First lactation monthly test day records of 2329 buffaloes sired by 79 sires distributed in 47 villages under field progeny testing programme in anand milk shed were used to evaluate sires for age at first calving (AFC), first lactation predicted milk yield (FLY305) and milk fat percent (fat%) traits. The objective of the study was to estimate the sire breeding value and to compare various methods of sire evaluation viz.simple daughter's average (D) , contemporary comparison (CC), least squares (LS), best linear unbiased prediction (BLUP) and average information restricted maximum likelihood (AIREML) in terms of accuracy and efficiency. Heritability estimates by Least Square-Analysis of Variance (LS-ANOVA) method were 0.252 ± 0.044, 0.065 ± 0.032 and 0.073 ± 0.035, respectively for AFC, FMY305 and Fat%. The genetic correlation of AFC with FLY305 and Fat% were-0.782 ± 0.192 and-0.451, respectively while the same between FLY305 and fat percent was 1.044 ± 0.39. The phenotypic correlations of FLY305 with Fat % and AFC were-0.042 and 0.109, respectively while same between Fat % and AFC was-0.099. For AFC, the AIREML had the lowest error variance than LS and BLUP, thus was the most efficient method. For FMY305 and Fat%, the BLUP was found to have lowest error variance and therefore, was the most efficient method. The relative accuracies in terms of rank correlations of D, CC, LS and BLUP methods with most efficient AIREML method were 0.35, 0.90, 0.37 and 0.97, respectively for AFC. For FLY305, the value of rank correlations of D, CC, LS and AIREML with most efficient BLUP method were 0.71, 0.71, 0.72 and 0.98, respectively. The value of rank correlations of D, CC, LS and AIREML with most efficient BLUP method were 0.89, 0.89, 0.95 and 0.99, respectively.