Sina Azad; hamid Amanlou; Najme Eslamian Farsuni; Tahere Amirabadi Farahani; Mohammad hadi Khabbazan
Volume 25, Issue 1 , April 2023, , Pages 37-50
Abstract
In the current study, the effect of source and level of copper in the diet on production and health of dairy cows using 105 multiparous pregnant Holstein cows from -21 until +15 days relative to calving in randomized complete block design with 3 treatments and 35 replications were investigated. The experimental ...
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In the current study, the effect of source and level of copper in the diet on production and health of dairy cows using 105 multiparous pregnant Holstein cows from -21 until +15 days relative to calving in randomized complete block design with 3 treatments and 35 replications were investigated. The experimental treatments include: 1) diet containing copper at the NRC recommended levels from copper sulfate source (NRC-S), 2) diet containing copper at twice the NRC recommended levels from copper glycinate source (2NRC-Gly) and 3) diet containing copper at twice the NRC recommended levels from copper sulfate source (2NRC-S). Milk yield and composition were not affected by experimental treatments, but treatment by time interaction showed that cows fed by 2NRC-Gly had more milk than NRC-S group (P<0.05) at 60, 90,120 DIM and cow in 2NRC-Gly produced more milk at 90 and 120 days in milk compared to NRC-S (P<0.05). The somatic cells count for 2NRC-Gly cows was lower compared to NRC-S cows (P 0.05). The incidence of subclinical mastitis at 15 DIM in 2NRC-Gly was lower compared to the other two treatments (P = 0.05). No difference in body weight and body condition score changes were observed across treatments. Blood metabolites and liver enzymes were not affected by adding different Cu sources, but serum albumin postpartum was increased in 2NRC-Gly group relative to the other two groups (P 0.05). Based on the results, adding copper especially by copper glycinate source at twice the NRC recommended levels led to an increase in the serum albumin concentration, a decrease in milk somatic cells count and lower incidence of subclinical mastitis, which could indicate an improvement in health of cows during transition period.
Fateme Ahmadi; hamid Amanlou; Tahere Amirabadi Farahani; Najme Eslamian Farsuni
Volume 24, Issue 4 , December 2022, , Pages 415-425
Abstract
The aim of the present study was to evaluate the effect of supplementing close-up diets of Holstein dairy cows with rumen undegradable protein (RUP) on milk yield, calf birth weight and colostrum composition during the hot season. Eighty-eight multiparous Holstein dairy cows were enrolled in the study ...
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The aim of the present study was to evaluate the effect of supplementing close-up diets of Holstein dairy cows with rumen undegradable protein (RUP) on milk yield, calf birth weight and colostrum composition during the hot season. Eighty-eight multiparous Holstein dairy cows were enrolled in the study 30 d before expected calving and assigned to 1 of 2 treatments groups: low crude protein (14.3% CP with 4.0% RUP based on DM) and high crude protein (17.1% CP with 6.0% RUP based on DM). Diets were fed for ad libitum intake during the close-up and fresh period. After calving, all cows received the same diet from calving to 21 days of milk. Milk production of all cows was recorded daily from the day of calving to 21 days after calving. The milk samples of each cow were collected twice a week to measure milk composition. The evaluation of body condition score (BCS) was performed at -30, -3, 0, and 21 d relative to calving. The production of milk and the amount of milk protein and lactose were greater and milk fat content was lower in cows fed high protein diet than cows fed low protein diet (P<0.05). The BCS changes were not different between cows of two treatments in pre- and post-partum periods. According to the results, feeding a diet containing high RUP content to close-up cows during the hot season increases milk yield and decreases milk fat percentage in fresh cows.
Fateme Ahamadi; hamid Amanlou; Najme Eslamian Farsuni; Tahere Amirabadi Farahani
Volume 23, Issue 3 , September 2021, , Pages 363-374
Abstract
The objective of this study was to investigate the effect of decreasing dietary protein content with supplementing protected methionine (pMet) and lysine (pLys) on intake, milk yield, metabolic status, and apparent digestibility of nutrients in Holstein fresh cows. Immediately after calving, 16 cows ...
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The objective of this study was to investigate the effect of decreasing dietary protein content with supplementing protected methionine (pMet) and lysine (pLys) on intake, milk yield, metabolic status, and apparent digestibility of nutrients in Holstein fresh cows. Immediately after calving, 16 cows with the similar BCS and parity were randomly assigned to two treatments. Experimental diets provided equal amounts of lysine (132 to 133 g/d) and methionine (40 to 43 g/d). The treatments were: a diet containing 18.35 % CP without supplementing pMet and pLys (HP); and a diet containing 16.45 % CP with supplementing rumen-protected amino acids (LPML). Individual dry matter intake and milk yield were recorded daily during fresh period. Blood samples were collected at 0, 3, 7, 14 and 21 d after calving to determine the serum concentrations of mineral and metabolites. Feed intake was not affected by experimental diets but milk yield was higher for HP cows than cows in LPML (P < 0.01). The yield of milk protein, lactose, fat and concentration of milk urea nitrogen (MUN) were higher in HP cows compared to LPML (P < 0.05). Compared to HP cows, cows in LPML had lower blood urea nitrogen (BUN) and higher serum concentrations of total protein and globulin (P < 0.01). Based on the results of the present study, reducing dietary protein content while maintaining the supply of limiting amino acids decreased lactational performance and feed efficiency of Holstein fresh cows.
Mehrdad Shahizad; hamid Amanlou; Najme Eslamian Farsuni; Tahere Amirabadi Farahani; Hadi Khabazan
Volume 22, Issue 3 , September 2020, , Pages 349-356
Abstract
The objective of present study was to investigate the effect of different levels of sesame meal in early lactation cow's ration on dry matter intake, milkyield and composition, apparent digestibility of nutrients and blood metabolites. Six dairy lactating Holstein cows with average DIM 26± 3 (n=3primiparous ...
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The objective of present study was to investigate the effect of different levels of sesame meal in early lactation cow's ration on dry matter intake, milkyield and composition, apparent digestibility of nutrients and blood metabolites. Six dairy lactating Holstein cows with average DIM 26± 3 (n=3primiparous and n=3 multiparous cows) were randomly assigned to 1 of 3 experimental treatments (different levels of sesame meal) in repeated 3×3Latin square design. Experimental treatments were control (without sesame meal), 4.33% sesame meal and 8.66% sesame meal (DM basis). Theexperimental periods consisted of 21 d with the first 14 days as adaptation and the last 7 days as sampling days. Increasing level of sesame meal inearly lactation rations did not affect dry matter intake, milk yield and composition (fat, protein and lactose), feed utilization efficiency, apparentdigestibility of nutrients and blood metabolites (P 0.05), while milk urea nitrogen decreased with increasing the level of sesame meal (p < 0.05).Blood urea nitrogen concentrations also tended (P = 0.1) to decrease with increasing levels of sesame oil. In general, the lack of response in feedintake and milk yield with increasing the levels of sesame meal in early lactation cow's ration showed that sesame meal could be a proper proteinsource in early lactation cow's ration.