First Month Of Lactation Research Articles

Genetic and environmental relationships between body condition score and milk production traits in Canadian Holsteins

The objective of this research was to estimate genetic parameters of first-lactation body condition score (BCS), milk yield, fat percentage (Fat%), protein percentage (Prot%), somatic cell score (SCS), milk urea nitrogen (MUN), lactose percentage (Lact%), and fat to protein ratio (F:P) using multiple-trait random regression animal models. Changes in covariances between BCS and milk production traits on a daily basis have not been investigated before and could be useful for determining which BCS estimated breeding values (EBV) might be practical for selection in the future. Field staff from Valacta milk recording agency (Sainte-Anne-de-Bellevue, QC, Canada) collected BCS from Québec herds several times per cow throughout the lactation. Average daily heritabilities and genetic correlations among the various traits were similar to literature values. On an average daily basis, BCS was genetically unfavorably correlated with milk yield (i.e., increased milk yield was associated with lower body condition). The unfavorable genetic correlation between BCS and milk yield became stronger as lactation progressed, but was equivalent to zero for the first month of lactation. Favorable genetic correlations were found between BCS with Prot%, SCS, and Lact% (i.e., greater BCS was associated with greater Prot%, lower SCS, and greater Lact%). These correlations were strongest in early lactation. On an average daily basis, BCS was not genetically correlated with Fat% or MUN, but was negatively correlated with F:P. Furthermore, BCS at 5 and 50 d in milk (DIM) had the most favorable genetic correlations with milk production traits over the lactation (at 5, 50, 150, and 250 DIM). Thus, early lactation BCS EBV shows potential for selection. Regardless, this study showed that the level of association BCS has with milk production traits is not constant over the lactation. Simultaneous selection for both BCS and milk production traits should be considered, mainly due to the unfavorable genetic correlation between BCS with milk yield.

NMR Metabolomic Analysis of Dairy Cows Reveals Milk Glycerophosphocholine to Phosphocholine Ratio as Prognostic Biomarker for Risk of Ketosis

Ketosis is a common metabolic disease in dairy cows. Diagnostic markers for ketosis such as acetone and beta-hydroxybutyric acid (BHBA) are known, but disease prediction remains an unsolved challenge. Milk is a steadily available biofluid and routinely collected on a daily basis. This high availability makes milk superior to blood or urine samples for diagnostic purposes. In this contribution, we show that high milk glycerophosphocholine (GPC) levels and high ratios of GPC to phosphocholine (PC) allow for the reliable selection of healthy and metabolically stable cows for breeding purposes. Throughout lactation, high GPC values are connected with a low ketosis incidence. During the first month of lactation, molar GPC/PC ratios equal or greater than 2.5 indicate a very low risk for developing ketosis. This threshold was validated for different breeds (Holstein-Friesian, Brown Swiss, and Simmental Fleckvieh) and for animals in different lactations, with observed odds ratios between 1.5 and 2.38. In contrast to acetone and BHBA, these measures are independent of the acute disease status. A possible explanation for the predictive effect is that GPC and PC are measures for the ability to break down phospholipids as a fatty acid source to meet the enhanced energy requirements of early lactation.

Preterm Milk Oligosaccharides During the First Month of Lactation

Oligosaccharides represent one of the main components of human milk, and they have been assigned important biological functions for newborns. Qualitatively and quantitatively, their presence in milk is strictly related to the expression of the mother's Se and/or Le genes, on the basis of which 4 different milk groups have been described. The aim of the study was to provide new data on the oligosaccharide composition of preterm milk in relation to the 4 groups. High-pH anion-exchange chromatography was used to quantify levels of 23 oligosaccharides and lactose in 252 milk samples collected from 63 mothers during the first month of lactation and to identify the 4 milk groups. Substantial differences in oligosaccharide contents were found within the groups and were strictly related to the presence or absence of specific fucosyl-oligosaccharides. The highest concentration was found in group 1 (>20 g/L), the lowest level was found in group 4 (∼10 g/L), and intermediate values were observed in groups 2 and 3. No statistically significant differences in lactose concentrations were observed among the groups. Our data confirm lower lactose concentrations in preterm milk, compared with term milk, and they provide the first detailed characterization of oligosaccharides in preterm milk, demonstrating important differences in oligosaccharide contents in the 4 groups. These differences might exert an influence on several biological functions that are particularly important for preterm infants and currently are attributed to milk oligosaccharides.

Preterm Milk Oligosaccharides During the First Month of Lactation

Preterm Milk Oligosaccharides During the First Month of Lactation

Cow-specific risk factors for retained placenta, metritis and clinical mastitis in Holstein cows

The objective of this study was to evaluate the association between cow-specific risk factors and the lactational incidence risks of retained placenta (RP), metritis (MET) and clinical mastitis (CM) in 57,301 dairy cows on 20 large dairy herds in Iran between January 2005 and June 2009. A multivariable logistic regression model was used to identify risk factors for MET, RP and CM and quantify their odds ratio (OR). The lactational incidences of MET, RP and CM were 8%, 5.2% and 18.9%, respectively, and significant risk factors for MET were dystocia (OR = 4.32), stillbirth (OR = 6.26), RP (OR = 27.74), twin births (OR = 6.57), primiparity (OR = 1.68), calving during winter season (OR = 2.45) and male calves (OR = 2.41). Significant risk factors for RP were dystocia (OR = 3.17), stillbirth (OR = 3.18), abortion (OR = 8.46), milk fever (OR = 3.66), twin births (OR = 2.76), pluriparity (OR = 2.69), calving during winter season (OR = 1.86) and shorter gestation length of dairy cows (OR = 3.82). Also, significant risk factors for CM were RP (OR = 9.45), milk fever (OR = 12.36), pluriparity (OR = 2.83), calving during winter season (OR = 1.68) and the first months of lactation (P < 0.001)) and SCC concentrations at previous lactation (OR = 1.82). The current study indicates that differentiation can be made among cows in the risk of having MET, RP and CM based on a combination of cow factors. These differences among cows could be useful to aid the better detection of these diseases in the dairy herds.

Maternal Nutrient Restriction During Late Gestation and Early Postnatal Growth in Sheep Differentially Reset the Control of Energy Metabolism in the Gastric Mucosa

Fetal growth restriction followed by accelerated postnatal growth contributes to impaired metabolic function in adulthood. The extent to which these outcomes may be mediated centrally within the hypothalamus, as opposed to in the periphery within the digestive tract, remains unknown. In a sheep model, we achieved intrauterine growth restriction experimentally by maternal nutrient restriction (R) that involved a 40% reduction in food intake through late gestation. R offspring were then either reared singly to accelerate postnatal growth (RA) or as twins and compared with controls also reared singly. From weaning, all offspring were maintained indoors until adulthood. A reduced litter size accelerated postnatal growth for only the first month of lactation. Independently from postnatal weight gain and later fat mass, R animals developed insulin resistance as adults. However, restricted accelerated offspring compared with both the control accelerated and restricted restricted offspring ate less and had higher fasting plasma leptin as adults, an adaptation which was accompanied by changes in energy sensing and cell proliferation within the abomasum. Additionally, although fetal restriction down-regulated gene expression of mammalian target of rapamycin and carnitine palmitoyltransferase 1-dependent pathways in the abomasum, RA offspring compensated for this by exhibiting greater activity of AMP-activated kinase-dependent pathways. This study demonstrates a role for perinatal nutrition in the peripheral control of food intake and in energy sensing in the gastric mucosal and emphasizes the importance of diet in early life in regulating energy metabolism during adulthood.

Detection of endoplasmic reticulum stress markers and production enhancement treatments in transgenic goats expressing recombinant human butyrylcholinesterase

Compromised lactation physiology has been observed in transgenic animals, possibly due to the excessive demand placed by the expression of complex recombinant glycoproteins in the mammary gland. In previous studies we described lactation parameters and milk composition characteristics of transgenic goats expressing recombinant human butyrylcholinesterase in milk, and we showed evidence suggesting that lactation cessation could be associated with endoplasmic reticulum stress. We now report data from immunohistochemistry studies targeting activation transcription factor 6 and caspase 12, two signal transducers associated with endoplasmic reticulum stress, designed to further elucidate potential mechanisms responsible for the disruption in mammary epithelium function previously described. We found strong evidence of endoplasmic reticulum stress associated with the premature cessation of lactation. In addition, we utilized previously generated knowledge to design and test two treatments for enhanced productivity in transgenic goats. Pre-partum treatment with reserpine and dexamethasone to stimulate mammary priming for lactation resulted in a significant increase in milk production on day 1 (573±350 vs. 93±92mL; P<0.01), first week (8,832±2,286 vs. 5,946±2,039; P<0.01) and the first month of lactation (42.5±10 vs. 34.9±6kg; P<0.05) compared to untreated controls. Mammary infusions with inosine during the early stages of lactation to promote mammary stem-cell proliferation also resulted in significantly increased milk production volumes, ranging from 26 to 200% more milk, in the treated glands compared to placebo.

Rumen-protected choline supplementation in periparturient dairy goats: effects on liver and mammary gland

SUMMARYThe current study investigated the effects of supplementing rumen-protected choline (RPC) on metabolic profile, selected liver constituents and transcript levels of selected enzymes, transcription factors and nuclear receptors involved in mammary lipid metabolism in dairy goats. Eight healthy lactating goats were studied: four received no choline supplementation (CTR group) and four received 4 g RPC chloride/day (RPC group). The treatment was administered individually starting 4 weeks before expected kidding and continuing for 4 weeks after parturition. In the first month of lactation, milk yield and composition were measured weekly. On days 7, 14, 21 and 27 of lactation, blood samples were collected and analysed for glucose,β-hydroxybutyrate, non-esterified fatty acids and cholesterol. On day 28 of lactation, samples of liver and mammary gland tissue were obtained. Liver tissue was analysed for total lipid and DNA content; mammary tissue was analysed for transcripts of lipoprotein lipase (LPL), fatty acid synthase (FAS), sterol regulatory binding proteins 1 and 2, peroxisome proliferator-activated receptorγand liver X receptorα. Milk yield was very similar in the two groups, but RPC goats had lower (P&lt;0·05) plasmaβ-hydroxybutyrate. The total lipid content of liver was unaffected (P=0·890), but the total lipid/DNA ratio was lower (bothP&lt;0·05) in RPC than CTR animals. Choline had no effect on the expression of the mammary gland transcripts involved in lipid metabolism. The current plasma and liver data indicate that choline has a positive effect on liver lipid metabolism, whereas it appears to have little effect on transcript levels in mammary gland of various proteins involved in lipid metabolism. Nevertheless, the current results were obtained from a limited number of animals, and choline requirement and function in lactating dairy ruminants deserve further investigation.

Productive level and energy balance in buffalo cow

Buffalo cow, at the beginning of lactation, shows a decrease in DM intake which determines a condition of physiologic hyponutrition (Campanile et al., 1997). In order to ensure physiologic haematic levels of glucose, the organism mobilizes the fat deposits and muscle proteins. Aim of present study was to evaluate the loss of body weight during the first months of lactation and the energy required for standard milk production in buffalo cow........

Relationship between body condition score, body weight, some nutritional metabolites changes in blood and reproduction in Algerian Montbeliad cows

The objective of this study was to investigate through a nutritional and biochemical approach the variability of reproductive performance in dairy cows of semi arid area herds. Seventy four multiparous females reared in four farms were tracked from one month before calving to the third month postpartum. Information about reproductive events were taken once a month, and the body condition score evaluated on a 1 to 5 scale according to the EDMONSON method (1989). Blood samples were taken on a sample of 23 cows chosen according to body condition score before calving for biochemical analysis of energy, nitrogen and minerals parameters. Maximum concentrations depended to physiological stage. Blood glucose and calcium are stable at around 0.60g / l and 0.76 g / l respectively (p>0.05). Uremia (0.27g/l vs 0.16g/l) and triglycerides (0.74g/l vs 0.48g/l) are higher in the first month of lactation (p 1.20 g / l) and low triglycerides (about 0.60 g / l). Great format Cows with early and significant loss of BC after calving. They express a poor reproductive performance with high triglycerides concentration (1.02 g / l) in the 1st month of lactation.

Very Preterm Gestation and Breastmilk Cytokine Content During the First Month of Lactation

High susceptibility to infection and deficient cytokine production in newborns make breastmilk beneficial, especially for very preterm-born infants. This study was conducted to identify the association between very preterm gestation and levels of pro- and anti-inflammatory cytokines in transitional and mature breastmilk during the first month of lactation after adjustment for mode of delivery and parity. Four samples of breastmilk (6-8, 13-15, 20-22, and 27-29 days) were collected from each mother after term or very preterm delivery at gestational age of less than 32 weeks. We measured the concentration of interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-13, and tumor necrosis factor α (TNF-α) in the milk samples using a multiplex biometric immunoassay. Fifteen mothers of very preterm infants and five term-born infants provided 80 samples of breastmilk. We found that delivery at very preterm gestation was linked with lower IL-8 (687 ± 208 pg/dL, p < 0.003) and higher IL-10 (27.8 ± 14.2 pg/dL, p < 0.01) levels in transitional breastmilk. Significantly decreased IL-8 levels were also seen in mature preterm milk samples. Cesarean delivery was associated with increased breastmilk TNF-α and IL-6 (p < 0.01-0.05), but gestational age was not. Very preterm gestation does not substantially impact the cytokine content of breastmilk during the first month of lactation, which can be beneficial for the regional and systemic immune response of the very preterm infant with confirmed impairment of innate and adaptive immunity.

Effect of lameness (hoof disorders) on productivity of Karan Fries crossbred cows

In present study production performance of 96 lame cows was compared with 67 healthy cows. No significant effect of parity and year of calving on milk yield were observed but the effect of season of calving was significant (P < 0.01). Effect of lameness on milk yield at the second, third and fourth months and 305 days was highly significant (P < 0.01), and was also significant (P < 0.05) on lactation yield of the fifth and tenth months. The effect of lameness on monthly and 305-day milk yield was significant (P < 0.01) only for those cows diagnosed lame before calving and during the first month of lactation. The differences in mean monthly yield were highly significant (P < 0.01) at the second, third and fourth months; and significant (P < 0.05) in the first and fifth months. The loss in the first lactation month of cows which were diagnosed as lame in the second month, was found to be significant (P < 0.05). Thus the yield of the month previous to the diagnosis (sub-clinical stage) was also affected. A significant (P < 0.01) total loss of 498.95 kg of milk yield was observed during a period of 305 days.

The effect of selenium supplementation before calving on early-lactation udder health in pastured dairy heifers

Selenium (Se) deficiency has been associated with lowered resistance to mastitis in dairy cattle. However, little published data exists on the effect of Se supplementation before calving on udder health of pastured dairy heifers. Further, the relative efficacy of injectable barium selenate and oral organic Se for improving udder health in cows has not previously been tested. The objectives of this study were to determine the effects of precalving Se supplementation and type of supplementation on the blood activity of glutathione peroxidase and measures of udder health immediately after calving and during the first month of lactation in pastured dairy heifers. One hundred forty pregnant Chilean Holstein-Friesian heifers were fed a basal diet containing, on average, 0.15mg of Se/kg of dry matter. One month before predicted calving, heifers were allocated to 1 of 3 groups. Group 1 (n=49) received no supplementary Se, group 2 (n=46) received a single subcutaneous injection of Se (1mg/kg of live weight, as barium selenate), and group 3 (n=45) was fed Se yeast (3mg/heifer/d until calving). Heifers supplemented with barium selenate had a higher glutathione peroxidase activity from 14 d in milk onwards. Selenium supplementation, irrespective of source, tended to reduce the prevalence of intramammary infection (IMI) and decrease the prevalence of quarters with high somatic cell count (SCC) at calving. Overall, Se supplementation did not result in a reduction of the incidence of new IMI or clinical mastitis or in decreased SCC during the balance of the first month of lactation. However, in pasture-based heifers injected with barium selenate before calving, and fed diets with 1.3 and 2.5mg of Se/d precalving and during lactation, respectively, no cases of clinical mastitis were observed in the first month of lactation.

Label-free liquid chromatography–tandem mass spectrometry analysis with automated phosphopeptide enrichment reveals dynamic human milk protein phosphorylation during lactation

Protein phosphorylation is a critical posttranslational modification that affects cell–cell signaling and protein function. However, quantifying the relative site-specific changes of phosphorylation occupancies remains a major issue. An online enrichment of phosphopeptides using titanium dioxide incorporated in a microchip liquid chromatography device was used to analyze trypsin-digested human milk proteins with mass spectrometry. The method was validated with standards and used to determine the dynamic behavior of protein phosphorylation in human milk from the first month of lactation. α-Casein, β-casein, osteopontin, and chordin-like protein 2 phosphoproteins were shown to vary during this lactation time in an independent manner. In addition, changes in specific regions of these phosphoproteins were found to vary independently. Novel phosphorylation sites were discovered for chordin-like protein 2, α-lactalbumin, β-1,4-galactosyl transferase, and poly-Ig (immunoglobulin) receptor. Coefficients of variation for the quantitation were comparable to those in other contemporary approaches using isotopically labeled peptides, with a median value of 11% for all phosphopeptide occupancies quantified.

Factors predicting early discontinuation of exclusive breastfeeding in the first month of life

To investigate factors associated with discontinuation of exclusive breastfeeding in the first month of lactation, in the city of Feira de Santana, Brazil. Cohort study with follow-up of 1,309 mother-child pairs selected from all maternities in the municipality. Data were collected in hospital and in home visits during the first month of life. Logistic regression analysis was used to examine the relationship between outcome and variables of interest. Lack of prior breastfeeding experience (PR 1.24; 95%CI 1.75-1.43), cracked nipples (PR 1.25; 95%CI 1.09-1.43), use of fixed breastfeeding schedules (PR 1.42; 95%CI 1.09-1.84) and pacifier use (PR 1.53; 95%CI 1.34-1.76) were identified as factors predicting discontinuation of exclusive breastfeeding. Measures to prevent early discontinuation of exclusive breastfeeding must focus on women without breastfeeding experience and include prevention of nipple trauma, encourage breastfeeding on demand, and discourage the use of pacifiers.

Association between milk yield and serial locomotion score assessments in UK dairy cows

This study investigated the effect of lameness, measured by serial locomotion scoring over a 12-mo period, on the milk yield of UK dairy cows. The data set consisted of 11,735 records of test-day yield and locomotion scores collected monthly from 1,400 cows kept on 7 farms. The data were analyzed in a multilevel linear regression model to account for the correlation of repeated measures of milk yield within cow. Factors affecting milk yield included farm of origin, stage of lactation, parity, season, and whether cows were ever lame or ever severely lame during the study period. Cows that had been severely lame 4, 6, and 8mo previously gave 0.51kg/d, 0.66kg/d, and 1.55kg/d less milk, respectively. A severe case of lameness in the first month of lactation reduced 305-d milk yield by 350kg; this loss may be avoidable by prompt, effective treatment. Larger reductions can be expected when cases persist or recur. Evidence-based control plans are needed to reduce the incidence and prevalence of lameness in high yielding cows to improve welfare and productivity.

Effect of nonclinical Staphylococcus aureus or coagulase-negative staphylococci intramammary infection during the first month of lactation on somatic cell count and milk yield in heifers

Coagulase-negative staphylococci (CNS) are the most prevalent cause of intramammary infections in heifers around calving, but Staphylococcus aureus should not be ignored because it is also prevalent, contagious, and more likely to persist into lactation. The objective of this study was to determine the effect of a subclinical infection caused by S. aureus or CNS diagnosed during the first month of lactation in heifers on SCC, milk production, and culling risk during the entire first lactation. Data were obtained from a cohort of 50 farms following a mastitis monitoring and control program and subscribing to the animal health record system (DS@HR) through the ambulatory clinic of the Faculté de médecine vétérinaire of the Université de Montréal (St-Hyacinthe, Québec, Canada). This program included routinely collecting a composite milk sample at each farm visit from all recently freshened heifers. A total of 2,273 Holstein heifers were examined. Among the 1,691 heifers meeting the full selection criteria, 90 (5%) were diagnosed with S. aureus, 168 (10%) were diagnosed with CNS, and 153 (9%) were negative (no pathogen isolated). Test-day natural logarithm somatic cell count (lnSCC) was modeled in a repeated measures linear regression model with herd as random effect. The model-adjusted mean lnSCC in S. aureus and CNS groups were significantly higher than in the culture-negative group from 40 to 300 d in milk. At the test-day level, lnSCC in S. aureus and CNS groups were on average 1.2 and 0.6 higher, respectively, than the culture-negative group. A similar model for milk yield showed that mean milk yield was not statistically different between culture groups from 40 to 300 d in milk. The presence of a S. aureus or CNS intramammary infections in the first month of lactation in heifers correlates with future increased SCC over the entire first lactation.

Lipid Fractions and Fatty Acid Composition of Colostrums, Transitional and Mature She-Camel Milk During the First Month of Lactation*

Lipid Fractions and Fatty Acid Composition of Colostrums, Transitional and Mature She-Camel Milk During the First Month of Lactation*

Somatic cell count dynamics in a large sample of dairy herds in England and Wales

An essential reason to record and evaluate patterns of cow somatic cell count (SCC) within a dairy herd is to help in making clinical decisions on the control of mastitis. An understanding of when new infections occur and how patterns of infection influence herd bulk milk somatic cell count (BMSCC) are critical when implementing mastitis control because it enables advisors to target specific problem areas. The objective of this research was to evaluate individual cow SCC patterns in terms of their contribution to BMSCC. Data collected in 2128 herds from England and Wales between 2004 and 2006 were used. Cows were categorised as having a low, medium or high SCC based on thresholds of 100,000 cells/mL and 200,000 cells/mL. Movements between these categories in consecutive months, before or after 30 days in milk, in primiparous ( heifers) and multiparous cows ( cows) were used to predict BMSCC. From these categories, new variables representing different SCC patterns, were calculated and included in different models: the medium SCC category was grouped with either the low or the high category, and the denominator was either the total number of cows recorded during the herd-year or the number of cows eligible for a particular transition. Model fitting and predictions were carried out in a Bayesian framework. A random sample of 1500 herds was used for parameter estimation and the remaining 628 herds for model validation. Heifers were more likely to remain at, or to move to, a low SCC than cows. A transition threshold of 100,000 cells/mL for heifers resulted in a poorer model fit and predictive ability than a threshold of 200,000 cells/mL. A model using a single threshold of 200,000 cells/mL regardless of parity was the best to predict BMSCC. The sensitivity and specificity of this final model to correctly predict a BMSCC > 200 , 000 cells/mL in the validation dataset were 86.5% and 86.8%, respectively. Important SCC patterns that influenced BMSCC were cows and heifers staying above 200,000 cells/mL for two consecutive recordings during lactation, cows moving from below to above 200,000 cells/mL across the dry period, cows remaining above 200,000 cells/mL across the dry period and heifers calving with an SCC above 200,000 cells/mL in the first month of lactation. The variation between herds in SCC transitions was evaluated and it was concluded that the performance of the top 10% of herds would be useful to provide benchmarks to evaluate dairy herd mastitis.

Biologically active breast milk proteins in association with very preterm delivery and stage of lactation

The aim of this study was to identify the independent effect of very preterm gestation on breast milk content of biologically active proteins (secretory immunoglobulin A (sIgA), lysozyme, lactoferrin, osteoprotegerin (OPG), leptin, adiponectin and β-endorphin (b-EP)) during the first month of lactation. We collected samples of transitional (6 to 8 and 13 to 15 days) and mature (20 to 22 and 27 to 29 days) milk from mothers after term (38 to 41 weeks) or very preterm (24 to 31 weeks) delivery. The levels of sIgA, lysozyme, lactoferrin, OPG, leptin, adiponectin and b-EP in the breast milk were quantified using enzyme-linked immunosorbent assay or enzyme immunoassay kits. Statistical analysis included descriptive statistics and regression analysis. Sixty breast milk samples were collected from 15 mothers after very preterm (preterm breast milk, PBM) and 20 samples from 5 mothers after term (term breast milk, TBM) deliveries. Decrease in lysozyme, lactoferrin, OPG, leptin, adiponectin and b-EP but no change in sIgA was recorded during the first month of lactation in both TBM and PBM. The IgA, lysozyme and adiponectin were higher in PBM than in TBM, whereas concentrations of lactoferrin, OPG and leptin were higher in TBM than in PBM (P<0.05 to 0.0001). A similar pattern was seen in the lysozyme, leptin and adiponectin concentration in mature milk. Increased b-EP levels in breast milk were associated with the vaginal mode of delivery but not gestational age. Although a similar pattern of change was observed in the breast milk bioactive proteins during the first month of lactation after term and very preterm gestation, PBM is a better source of factors with antibacterial/anti-inflammatory activities but is constantly deficient in leptin, which is involved in neuroendocrine regulation.