• Title/Summary/Keyword: lactation

Search Result 946, Processing Time 0.033 seconds

Effects of Long Term Exogenous Bovine Somatotropin on Nutrients Uptake by the Mammary Gland of Crossbred Holstein Cattle in the Tropics

  • Chaiyabutr, Narongsak;Thammacharoen, S.;Komolvanich, S.;Chanpongsang, S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.20 no.9
    • /
    • pp.1407-1416
    • /
    • 2007
  • Ten, first lactation, 87.5%HF dairy cattle were used to investigate effects of long-term administration of recombinant bovine somatotropin (rbST) on nutrient uptake by the mammary gland at different stages of lactation. Measurements of arterial plasma concentrations and arterial-venous differences of metabolites across the mammary gland were performed in combination with measurment of mammary blood flow to estimate the mammary uptake. Animals in experimental groups were injected subcutaneously every 14 days from day 60 of lactation with a prolonged-release formulation of 500 mg of rbST (POSILAC, Monsanto, USA) or with sterile sesame oil without rbST in the control group. During early lactation, the milk yield of rbST-treated animals was higher than that of the control animals (p<0.05). The peak milk yield in both groups of animals declined from the early period of lactation with progression to mid- and late-lactation. No significant changes were observed in the concentration of milk lactose, while the concentrations of milk protein significantly increased as lactation advanced to mid- and late-lactation in both groups. Milk fat concentrations were significantly higher in rbST-treated animals than in control animals, particularly in early lactation (p<0.05). Mammary blood flow (MBF) markedly increased during rbST administration and was maintained at a high level throughout lactation. The mean arterial plasma concentrations for glucose and acetate of rbST-treated animals were unchanged. The net mammary glucose uptake of rbST-treated animals increased approximately 20% during early lactation, while it significantly decreased (p<0.05), including the arteriovenous differences (A-V differences) and extraction ratio across the mammary gland, as lactation advanced to mid- and late-lactation. A-V differences, mammary extraction and mammary uptake for acetate increased during rbST administration and were significantly higher (p<0.05) than in the control animals in early and mid-lactation. Mean arterial plasma concentrations for ${\beta}$-hydroxybutyrate and free glycerol were unchanged throughout the experimental periods in both groups. A-V differences and extraction ratio of ${\beta}$-hydroxybutyrate across the mammary gland did not alter during rbST administration. Mean arterial plasma concentrations for free fatty acids ($C_{16}$ to $C_{18}$), but not for triacylglycerol, increased in rbST-treated animals and were significantly higher than in control animals during early lactation (p<0.01). These findings suggest that an increase in MBF during rbST administration would not be a major determinant in the mediation of nutrient delivery and uptake by the mammary gland for increased milk production. Local changes in biosynthetic capacity within the mammary gland would be a factor in the utilization of substrates resulting in the rate of decline in milk yield with advancing lactation.

Production Characteristics of Nili-Ravi Buffaloes

  • Khan, R.N.;Akhtar, S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.12 no.1
    • /
    • pp.56-60
    • /
    • 1999
  • Production and reproduction data of 47 Nili-Ravi buffaloes (162 records) were analyzed with regression techniques. Average lactation milk yield was $2,020.04{\pm}44.59$ liters, lactation length $277.42{\pm}5.70$ d and calving interval $467.10{\pm}11.58$ d. The ranges for these parameters respectively were : 609-3591 lit, 122-614 d and 228-982 d. Year of calving and lactation length had significant effect on total milk yield (p < 0.01), whereas other factors such as month of calving, lactation number and calving interval had no effect on total lactation milk yield. Year of calving had influenced significantly other traits (p < .01) such as calving interval and lactations completed. This indicated considerable environment role in buffalo productivity. Effect of month of calving on total lactation milk yield and other traits was however, found to be non-significant. Nili-Ravi buffaloes produced maximum milk during their first three lactations as compared to subsequent lactations. Regression model explained 40 percent variation in total lactation milk yield due to factors analyzed : animal (dam), year and month of calving lactation length and calving interval.

Dairy Potential of Pabna Cows and Crossbreds with Sahiwal and Friesian and Within- and Between-Breed Sire Effects

  • Hoque, M.A.;Amin, M.R.;Hussen, M.S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.12 no.2
    • /
    • pp.161-164
    • /
    • 1999
  • Dairy performances of Pabna cows and its crossbreds with Sahiwal (SL) and Friesian (F) in the Baghabarighat dairying area of Bangladesh were evaluated. Four SL and three F sires were used for the crossbreeding. The exotic sire effect of individuals on their daughters were also evaluated in this study. It showed that the genetic group had a significant (p<0.05) effect on birth weight, age at first heat, calving interval, lactation length and lactation yield. The lowest birth weight (17.9 kg), longest age at first heat (39.2 m) and calving interval (16.3 m) shortest lactation length (199 d) and lowest lactation yield (728 L) were found in Pabna cows. The highest birth weight (22.5 kg). shortest age at first heat (25.5 m) and calving interval (13.7 m), longest lactation length (253 d) and highest lactation yield (1936 L) were found in the F crossbreds. Within the same breed, the effect of individual sire was significant (p<0.05) on age at first heat, lactation length and lactation yield. Individual sire effects of SL bulls differed significantly (p<0.05) but F sires had a non-significant (p>0.05) effect on calving interval in their progeny. The fat % and SNF % in milk and number of services required for conception did not differ (p>0.05) among inter-and intra- breed sire groups.

Lactation and Function of Curve Parameters in Yankasa Sheep

  • Afolayan, R.A.;Abubakar, B.Y.;Osinowo, O.A.;Dim, N.I.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.6
    • /
    • pp.890-894
    • /
    • 2002
  • The accuracy of the gamma function to describe lactation curve of Yankasa ewes was investigated using milk production data obtained from 168 ewes with either complete or incomplete 84 day lactation records. Ewes were daily hand milked after over-night separation from lamb and thorough disinfection of the udder. The daily milk yield on the average was estimated from the weekly total yield. The effect of type of birth, parity, season of birth and lactation length on the components of lactation curve (a, b, c and s) were analysed by least-square procedures. All factors except parity significantly (p<0.01) influenced the curve parameters. The goodness of fit of the function did not differ between the two classes of varying duration of lactation; incomplete lactation however, showed a lower persistency and as expected lower level of production. Correlations ($r_p$) between lamb weight gain and milk yield using the weight records from lamb weighed at weekly intervals indicated a high and positive relationship in the early lactation that decreased in intensity as the lactation advanced.

Selection of Sahiwal Cattle Bulls on Pedigree and Progeny

  • Bhatti, A.A.;Khan, M.S.;Rehman, Z.;Hyder, A.U.;Hassan, F.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.20 no.1
    • /
    • pp.12-18
    • /
    • 2007
  • The objective of the study was to compare ranking of Sahiwal bulls selected on the basis of highest lactation milk yield of their dams with their estimated breeding values (EBVs) using an animal model. Data on 23,761 lactation milk yield records of 5,936 cows from five main Livestock Experiment Stations in Punjab province of Pakistan (1964-2004) were used for the study. At present the young A.I bulls are required to be from A-category bull-dams. Dams were categorized as A, B, C and D if they had highest lactation milk yield of ${\geq}$2,700, 2,250-2,699, 1,800-2,249 and <1,800 litres, respectively. The EBVs for lactation milk yield were estimated for all the animals using an individual animal model having fixed effect of herd-year and season of calving and random effect of animal. Fixed effect of parity and random effect of permanent environment were incorporated when multiple lactation were used. There were 396 young bulls used for semen collection and A.I during 1973-2004. However, progeny with lactation yields recorded, were available only for 91 bulls and dams could be traced for only 63 bulls. Overall lactation milk yield averaged 1,440.8 kg. Milk yield was 10% heritable with repeatability of 39%. Ranking bulls on highest lactation milk yield of their dams, the in-vogue criteria of selecting bulls, had a rank correlation of 0.167 (p<0.190) with ranking based on EBVs from animal model analysis. Bulls' EBVs for all lactations had rank correlation of 0.716 (p<0.001) with EBVs based on first lactation milk yield and 0.766 (p<0.001) with average EBVs of dam and sire (pedigree index). Ranking of bulls on highest lactation yield of their dams has no association with their ranking based on animal model evaluation. Young Sahiwal bulls should be selected on the basis of pedigree index instead of highest lactation yield of dams. This can help improve the genetic potential of the breed accruing to conservation and development efforts.

Effects of Energy Intake on Performance, Mobilization and Retention of Body Tissue, and Metabolic Parameters in Dairy Cows with Special Regard to Effects of Pre-partum Nutrition on Lactation - A Review -

  • Remppis, S.;Steingass, H.;Gruber, L.;Schenkel, H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.24 no.4
    • /
    • pp.540-572
    • /
    • 2011
  • The present review focuses on the effects of energy intake on performance, changes in body tissue during lactation, and metabolic parameters in dairy cows. Especially, pre-partum nutrition and its influence on lactation are emphasized. In recent decades the increase in genetic potential of dairy cows has increased milk yield. This fact sharpens the problem of a negative energy balance in early lactation because the amount of energy required for maintenance and milk production exceeds the amount of energy cows can consume. Around parturition, reduced feed intake reinforces the situation. Continuing negative energy balance causes decreasing milk yield, fertility problems, and incidence of metabolic diseases. Hence, the cow has to rely on body reserves that were stored in late lactation and the dry period. It is evident that the nutritional status pre-partum acts as the key factor for milk yield and fertility parameters in the following lactation. Cows overfed during the foregoing gestation and which have gained large quantities of body fat have lower dry matter intake along with the need to mobilize larger quantities of body reserves in lactation. The milk yield in the following lactation is lower than in cows fed according to their requirements. Cows restrictively fed in late gestation have a higher feed intake in lactation and a lower mobilization of body reserves. The effect of energy intake post-partum plays only a minor role for performance parameters in lactation. Lipid mobilized from body reserves makes a substantial contribution to the energetic cost of milk production in early lactation and adipose tissue undergoes specific metabolic alterations. Adipose tissue is degraded to free fatty acids, which are used in liver for energy purposes. High lipid mobilisation promotes the development of a fatty liver and therefore a reduced gluconeogenesis.

Metabolic profile according to the parity and stage of lactation of high-performance Holstein-Friesian cows

  • Kuczynska, Beata;Puppel, Kamila;Golebiewski, Marcin;Wisniewski, Konrad;Przysucha, Tomasz
    • Animal Bioscience
    • /
    • v.34 no.4
    • /
    • pp.575-583
    • /
    • 2021
  • Objective: The aim of the study was to determine the effect of parity and the stage of lactation on the metabolic profile of cows based on the basic chemical milk components and the blood parameters. Methods: The study material consisted of high-yielding Holstein-Friesian cows. In total, 473 cows were examined. According to the parity, cows were divided into four groups: primiparous (P), and multiparous in the second (M2), in the third (M3), and in subsequent lactations (M4). The feeding of cows was based on total mixed ration (TMR) ad libitum. Milk and blood samples were collected individually from each cow three times per standard lactation period. Results: Greater exacerbation of changes in the dynamics of the blood plasma parameters examined was proved for multiparous cows. The highest value of β-hydroxybutyrate acid (0.946 mmol/L) was found for multiparous cows from group M3 at the beginning of lactation. However, it was still in the normal range. The results showed aspartate aminotransferase, and gamma-glutamyl transferase (GGT) activities in dairy cows during lactation had significant variations taking in to account stage of lactation. The highest activity of GGT was found in the group of the oldest cows and measured from 26.36 U/L at the beginning of lactation to 48.75 U/L at the end of the lactation period. Conclusion: The time-related changes in the concentrations of the biochemical parameters described differ markedly among lactating cows, though the housing conditions on the research dairy farm are highly standardised. This indicates that the ability to cope with metabolic stress is mainly affected by the individual predispositions of cows and feed nutrient supply in different stage of lactation. Especially, the feed nutrient supply (in net energy for lactation), which was the best in TMR 1 in comparison TMR 3.

Response to Selection for Milk Yield and Lactation Length in Buffaloes

  • Khan, M.S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.10 no.6
    • /
    • pp.567-570
    • /
    • 1997
  • A multiple trait animal model having milk yield and lactation length was used to estimate genetic parameters using data from four institutional herds and four field recording centers. Response to selection for milk yield alone and in combination with lactation length was estimated by using principles of genetic theory. Lactation records (n = 2,353) adjusted for age at calving to 60 months were utilized. Milk yield was 17% heritable with repeatability of 0.44. Lactation length had a low heritability of 0.06 with repeatability of 0.16. Genetic correlation between the two traits was 0.70. Selection response in milk yield can be improved slightly (103.8 vs 102.8 kg) when information on covariance with lactation length is used together with the information on milk yield.

Plasma Levels of Hormones and Metabolites as Affected by the Forages Type in Two Different Types of Crossbred Holstein Cattle

  • Chaiyabutr, N.;Preuksagorn, S.;Komolvanich, S.;Chanpongsang, S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.13 no.10
    • /
    • pp.1359-1366
    • /
    • 2000
  • An experiment was carried out to study plasma levels of hormones and metabolites of crossbred Holstein cattle during late pregnancy (28 days pre partum), early lactation (30 days post partum), mid-lactation (120 days post partum) and late lactation (210 days post partum). Two breed types of Holstein $Friesian{\times}Red$ Sindhi (50:50 = 50%HF) and Holstein $Friesian{\times}Red$ Sindhi (87.5:12.5 = 87.5%HF) were divided into four groups of four animals each. Two groups of each breed were fed with either rice straw treated with 5% urea or pangola hay (Digitaria decumbens) as the source of roughage throughout the experiments. There were a substantial increases in the mean levels of total triiodothyronine ($T_3$), insulin and glucagon at the onset of lactation, and maintained in a high levels during lactation advance for all groups of experiments. The mean levels of prolactin and thyroxine ($T_4$) were not significantly different among groups of animals, but the plasma cortisol concentration was slightly higher in both groups of 50%HF in comparison with those of 87.5%HF animals. The mean levels of plasma growth hormone (GH) of both groups of 87.5%HF animals feeding on either hay or urea treated rice straw markedly rose in the early period of lactation and markedly reduced in mid- and late lactation. These changes were accompanied with changes of milk yield. In contrast to 50%HF animals, plasma GH levels were considerably higher in the late pregnant period than in the early period of lactation and it remained constant as its value at the early lactation throughout the experimental period. The high levels of both plasma progesterone and estradiol concentration significantly declined after parturition and remained low through lactating period. The plasma glucose level in the 50%HF animals feeding on either hay or urea treated rice straw was higher than the 87.5%HF animals in all periods of experiments. Changes in plasma FFA levels of both types of crossbred animals were depended on the endocrine status during late pregnancy and lactation. The levels of plasma FFA of 50%HF animals were significantly higher (p<0.05) than those of 87.5%HF animals during late pregnancy. Both plasma ${\beta}$-hydroxybutyrate and lactate concentrations were not affected by feeding on either hay or urea treated rice straw during late pregnancy and lactation. These data demonstrate that there were no differences in the physiological performances in the same crossbred animals fed either hay or urea treated rice straw. The 87.5%HF animal has the genetic potential for a high milk yield and homeorhetic adaptation for mammary function differed from 50%HF animals during periods of lactation. Altering lactation persistency in 87.5%HF is regulated mainly by chronically acting growth hormones through the period of lactation.

The Plasma Level of Insulin-like Growth Factor-I (IGF-I) in Relation to Mammary Circulation and Milk Yield in Two Different Types of Crossbred Holstein Cattle

  • Chaiyabutr, N.;Komolvanich, S.;Thammacharoen, S.;Chanpongsang, S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.17 no.3
    • /
    • pp.343-348
    • /
    • 2004
  • The objective of the present study was to determine the plasma level of insulin-like growth factor-I (IGF-I) in relation to mammary blood flow and milk yield including biological variables of relevance to milk synthesis in two different types of crossbred Holstein cattle at 3 different stages of lactation. Eight heifers were 87.5% HF and eight 50% HF animals were selected for the experiments. The three stages of lactation tested were: early lactation (30 days postpartum), mid-lactation (120 days postpartum) and late lactation (210 days postpartum). Animals in each group were fed a concentrate and rice straw treated with 5% urea as the source of roughage throughout the experiments. In early lactation, mammary blood flow and milk yield of 87.5% HF animals were significantly higher than those of 50% HF animals. In mid- and late lactation, both mammary blood flow and milk yield showed a proportional decrease from the early lactating period of 87.5% HF animals. The trends for persistency were observed in 50% HF animals as for udder blood flow and milk yield throughout the experimental periods. The plasma glucose level of the 50% HF animals was significantly higher than those of 87.5% HF animals in both early and mid-lactation. The concentrations of arterial plasma free fatty acids ($C_{16}\;to\;C_{18}$) were higher in 50% HF animals as compared with 87.5% HF animals in all periods of study. In early lactation, the concentration of plasma growth hormone (GH) of 87.5% HF animals was higher than those of the 50% HF animals, thereafter the mean level of plasma growth hormone declined in both mid- and late lactation. The concentration of plasma IGF-I of 50% HF animals was significantly higher than those of 87.5% HF animals in all stages of lactation. There were no differences among stages of lactation for the levels of plasma IGF-I, insulin and growth hormone in 50% HF animals. In 87.5% HF animals, the plasma levels of both IGF-I and insulin were lower in early lactating period while it showed an increase during mid- and late lactation. The present results indicated that the regulatory role for the higher mammary blood flow and milk yield during lactation in 87.5% HF are not mediated via the higher level of circulating IGF-I. Differences in mammary blood flow and milk yield between 50% HF and 87.5% HF animals are in part due to a higher concentration of circulating growth hormone. The lower level of circulating growth hormone in 50% HF animals would be regulated by higher levels of IGF-I, free fatty acid and glucose in plasma.