Colostral Fat Research Articles

Technical note: colorimetric methods for accurate determination of nutrient composition in beef cow colostrum and milk.

Our objectives were to develop colorimetric methods to accurately measure nutrient concentrations of beef cow colostrum and milk, to determine if the yield of colostrum from a single rear quarter is representative of complete collection of colostrum in beef cows, and to compare data from our developed colorimetric methods with Fourier transform infrared spectroscopy (FTIR) analysis to determine the accuracy of FTIR for beef cow colostrum and milk. In Exp. 1, colostral weight and volume of the most full rear quarter were compared with complete collection of colostrum from post-calving, unsuckled beef heifers. Both volume and weight had r2 = 0.85 (P < 0.001) between single-quarter and 4 quarter yields. In Exp. 2, colostrum (n = 35) and milk at d 35 (n = 42) and d 60 (n = 38) of lactation were collected from multiparous, fall-calving, crossbred beef cows. Subsamples were submitted for FTIR analysis and frozen for colorimetric analysis. Colorimetric analyses were developed for lactose, triglycerides (measure of fat), protein, and urea N. To validate method accuracy, spike recoveries were determined for lactose (96.8% average) and milk protein (100.1% average), triglyceride concentration was compared with fat concentration determined by the Mojonnier method (r2 ≥ 0.91, P < 0.001), and colostral or milk urea N was compared with serum urea N from the same sampling day (r2 ≥ 0.72, P < 0.001). Coefficients of determination between colorimetric methods and FTIR were determined for colostrum, d 35 milk, and d 60 milk. Colostral lactose concentration from FTIR was positively associated (r2 = 0.24, P = 0.01) with colorimetric analysis, but there was no relationship (r2 ≤ 0.09, P ≥ 0.14) between methods for colostral fat, protein, or urea N. Milk nutrient composition was positively associated for all nutrients measured at d 35 (r2 = 0.28 to 0.58, P < 0.001), and coefficients of determination strengthened for all nutrients measured at d 60 (r2 = 0.38 to 0.82, P < 0.001). In conclusion, colostrum yield of a single rear quarter can be used to indicate complete collection of colostrum for beef cows, and colorimetric methods developed have adequate accuracy for beef cow colostral and milk nutrient analysis. Based on our analyses, nutrient composition of beef cow colostrum was not accurately analyzed by FTIR. Accuracy of FTIR for beef cow milk varies with component and may be affected by the day of lactation.

Effect of β-carotene supplementation to prepartum Holstein cows on colostrum quality and calf performance

β-Carotene, a pro-vitamin A carotenoid, acts as an antioxidant, able to scavenge free radicals to prevent oxidative damage. It has also been shown to increase rumen microbial production in vitro. When supplemented prepartum, β-carotene increased colostral fat and protein concentrations. The objective of this experiment was to evaluate the effects of supplementing 700 mg/d β-carotene (BC) daily for 4 wk prepartum on cow performance, colostrum, and performance in subsequent calves. Eighteen multiparous Holstein cows housed in a tiestall barn were blocked by expected calving date and randomly assigned to treatments at 4 wk prepartum. Blood samples were collected 3 times a week for analysis of nonesterified fatty acids, ketones, β-carotene, and IgG. Urine samples were also collected 3 times a week for analysis of creatinine and purine derivatives. Colostrum was collected within 90 min after parturition. Calves were removed from their dams before suckling, weighed within 30 min of birth, and received 4 L of maternal colostrum. Blood samples were collected from calves before colostrum administration (0 h) and at 24 h via jugular venipuncture for analysis of IgG concentration and apparent efficiency of IgG absorption. The 18 calves born were blocked based on treatments of dams. All calves were fed 449 g/d dry matter of milk replacer (20% crude protein, 20% fat) and an 18% crude protein textured starter and water ad libitum at 2 d of age until weaning at 42 d. There were no differences in any blood parameters of cows during the prepartum period. Supplemental BC increased the solids content of colostrum compared with control (22.89% control; 27.75% BC). Calves born from control fed cows had greater efficiency of IgG absorption than those born from BC supplemented cows (52.16% control; 39.50%, BC). Calves born from BC fed cows had greater feed efficiency (average daily gain/dry matter intake) compared with those born from control supplemented cows (0.33 for control; 0.44 for BC). These data indicate that although supplementing β-carotene to cows in the prepartum period negatively affects apparent efficiency of IgG absorption, it improved feed efficiency in calves.

Immunoglobulin G content and colostrum composition of different goat and sheep breeds in Switzerland and Germany

Colostrum represents the sole source to acquire humoral immunity and is an important energy source for newborn lambs and goat kids. However, colostrum composition (i.e., the contents of IgG, fat, protein, and lactose) is affected by various factors such as parity and litter size and, potentially, by breed. In the present study, we examined the colostrum composition of different goat and sheep breeds raised for milk and meat production in Switzerland and Germany. Ten goat breeds (Anglo-Nubian, Appenzell, Boer, Bunte Deutsche Edelziege, Chamois-colored, Grisons Striped, Peacock, Saanen, Toggenburg, and Valais Blackneck) and 10 sheep breeds (Brown-Headed Meat, East Friesian Milk, German Blackheaded Mutton, Gray Horned Heath, Lacaune Dairy, Merino Land, Swiss Black-Brown Mountain, Swiss Charollais, Swiss White Alpine, and Valais Blacknose) were involved in this study. First colostrum samples were obtained from ewes (n = 100) and goats (n = 116) between 10 and 390 min after parturition and analyzed for total IgG, fat, protein, and lactose contents. Colostral IgG concentrations varied between 4.8 and 75.0 mg/mL in goats, and between 6.2 and 65.4 mg/mL in ewes, and the time interval between milking and parturition did not affect colostral IgG concentrations. In goats, the highest IgG concentrations were found in Boer (meat-type; 61.0 ± 10.3 mg/mL; mean ± SD) and the lowest concentrations were observed in Bunte Deutsche Edelziege (milk-type; 26.5 ± 12.5 mg/mL). In sheep, East Friesian Milk and Lacaune Dairy showed the lowest colostral IgG concentrations (17.9 ± 7.3 and 20.2 ± 8.0 mg/mL, respectively), and the highest values were observed in the Merino Land breed (44.2 ± 15.7 mg/mL). The lowest fat and protein concentrations and concomitantly highest lactose concentrations were observed in colostrum of East Friesian Milk and Lacaune Dairy sheep. Parity number did not affect colostrum composition in sheep or goats. In contrast, colostral fat content was higher in ewes bearing twins and triplets than in those carrying singletons. Increasing litter size tended to be associated with higher protein and lower lactose concentrations in ovine (i.e., singletons vs. twins vs. triplets) and caprine colostrum (i.e., singletons vs. twins), whereas colostral IgG concentrations were not affected by litter size. In conclusion, IgG and concentrations of other colostrum constituents showed a wide range in goats and ewes and were mainly affected by the type of breed.

Evaluation of factors associated with immunoglobulin G, fat, protein, and lactose concentrations in bovine colostrum and colostrum management practices in grassland-based dairy systems in Northern Ireland

The objectives of this study were to investigate colostrum feeding practices and colostrum quality on commercial grassland-based dairy farms, and to identify factors associated with colostrum quality that could help inform the development of colostrum management protocols. Over 1 yr, background information associated with dairy calvings and colostrum management practices were recorded on 21 commercial dairy farms. Colostrum samples (n = 1,239) were analyzed for fat, protein, lactose, and IgG concentration. A subset was analyzed for somatic cell count and total viable bacteria count. Factors associated with nutritional and IgG concentrations were determined using both univariate and multivariate models. This study found that 51% of calves were administered their first feed of colostrum via esophageal tube, and the majority of calves (80%) were fed >2 L of colostrum at their first feed (mean = 2.9 L, SD = 0.79), at a mean time of 3.2 h (SD 4.36) after birth, but this ranged across farms. The mean colostral fat, protein, and lactose percentages and IgG concentrations were 6.4%, 14%, 2.7%, and 55 mg/mL, respectively. The mean somatic cell count and total viable count were 6.3 log10 and 6.1 log10, respectively. Overall, 44% of colostrum samples contained <50 mg/mL IgG, and almost 81% were in excess of industry guidelines (<100,000 cfu/mL) for bacterial contamination. In the multivariate model, IgG concentration was associated with parity and time from parturition to colostrum collection. The nutritional properties of colostrum were associated with parity, prepartum vaccination, season of calving, and dry cow nutrition. The large variation in colostrum quality found in the current study highlights the importance of routine colostrum testing, and now that factors associated with lower-quality colostrum on grassland-based dairy farms have been identified, producers and advisers are better informed and able to develop risk-based colostrum management protocols.

Effect of dry period dietary energy level in dairy cattle on volume, concentrations of immunoglobulin G, insulin, and fatty acid composition of colostrum

The objective was to investigate the effect of different dry cow feeding strategies on the volume, concentration of IgG and insulin, as well as fatty acid composition of colostrum. Our hypothesis was that different dry period diets formulated to resemble current feeding practices on commercial dairy farms and differing in plane of energy would have an effect on IgG and insulin concentration, as well as composition of fatty acid of colostrum. Animals (n=84) entering parity 2 or greater were dried off 57d before expected parturition and fed either a diet formulated to meet, but not greatly exceed energy requirements throughout the dry period (CON), or a higher energy density diet, supplying approximately 150% of energy requirements (HI). A third group received the same diet as group CON from dry-off until 29d before expected parturition. After this time point, from 28d before expected parturition until calving, they received a diet formulated to supply approximately 125% of energy requirements (I-med). Concentration of IgG and insulin in colostrum were measured by radial immunodiffusion and RIA, respectively. Composition of fatty acids was determined by gas-liquid chromatography. The IgG concentration was highest in colostrum of cows in group CON [96.1 (95% CI: 83.3–108.9) g/L] and lowest in group HI [72.4 (60.3–84.5) g/L], whereas insulin concentration was highest in group HI [1,105 (960–1,250) μU/mL] and lowest in group CON [853 (700–1,007) μU/mL]. Colostrum yield did not differ between treatments and was 5.9 (4.5–7.4), 7.0 (5.6–8.4), and 7.3 (5.9–8.7) kg in groups CON, I-med, and HI, respectively. A multivariable linear regression model showed the effect of dietary treatment group on IgG concentration was independent of the effect of dry matter. Cows in groups CON, I-med, and HI had an average colostral fat percentage of 5.0 (4.1–5.9), 5.6 (4.8–6.4), and 6.0 (5.2–6.8) and an average fat yield of 289 (196–380), 406 (318–495), and 384 (295–473) g, respectively. Colostrum of cows fed to exceed predicted energy requirements during the last 4wk of the dry period (groups I-med and HI) exhibited a higher concentration and yield of de novo fatty acid and lower concentrations but similar yield of preformed fatty acid compared with cows in group CON. Feeding a controlled energy diet during the dry period increased colostral IgG concentration in this study, whereas overall colostrum yield was not affected. Exceeding energy requirements during the period of colostrogenesis led to higher concentrations of insulin and de novo fatty acid in colostrum.

Responses in colostrum production and immunoglobulin concentrations to conjugated linoleic acid fed to multiparous sows during late gestation

This study was conducted to determine whether supplemental conjugated linoleic acid (CLA) fed during late gestation affects reproductive performance, colostrum production and colostral immunoglobulin (Ig) levels of multiparous sows. Forty-eight, pregnant, Landrace×Large White, multiparous sows were allotted to four dietary treatments (n=12), control (CTR, no CLA addition) and 7.5, 15.0, or 22.5g/kg CLA supplementation from d 85 of gestation until farrowing. The CLA was added at the expense of soybean oil. All sows were fed the same commercial lactation diet postpartum. Blood samples were collected from sows on d 85, 100 and 112 of gestation while blood samples were obtained from neonatal piglets 24h postpartum. Colostrum was collected immediately after farrowing and its production was estimated for 24h starting with the birth of the first piglet. Neither the body weight nor backfat thickness of sows were altered by dietary CLA. Reproductive performance, piglet growth and calculated colostrum production were also unaffected. Compared with the CTR diet, dietary CLA supplementation during late gestation decreased (P<0.01) the colostral fat, and increased (P<0.01) the concentrations of IgG, IgA, and IgM in colostrum (P<0.01). The concentrations of serum Ig and interleukin-2 on d 112 of gestation were increased (P<0.01) in sows receiving CLA, although those factors did not differ among different levels of CLA supplementation. Serum IgG, IgA, and IgM concentrations in piglets from sows fed diets containing CLA were increased (P<0.05) 24h postpartum. This study indicates that dietary CLA has potential immunomodulatory effects in gestating sows and neonatal piglets, whereas there were no differences within the CLA treatments.

Sow and litter factors influencing colostrum yield and nutritional composition.

One of the main characteristics of colostrum intake (CI), colostrum yield (CY), and colostrum composition (CC) in pigs is its variability. The present observational study aimed to investigate factors influencing CY and CC in 10 commercial herds. In total, 100 sows of 5 different breeds and their 1,455 live-born piglets were included. Sows' CY was estimated by the CI of their suckling piglets. Colostrum composition was analyzed by LactoScope Fourier transform infrared spectroscopy. Colostrum yield averaged 3,500 ± 110 g and the percentage of colostral fat (CF), protein, and lactose in colostrum averaged 5.39 ± 0.12, 16.49 ± 0.14, and 2.02 ± 0.05 %, respectively. The effect of sow, litter, and parturition factors on CY and CC were evaluated with a linear mixed regression model with herd included as a random factor. Sows with a gestation length (GL) of 113 d had a higher CY (4,178 ± 506 g) than sows with a GL of 114 to 115 d (3,342 ± 107 g; = 0.04). An interaction was found between the litter birth weight of suckling piglets (LW) and GL ( = 0.03). In sows with a GL of 114 to 115 d, CY increased with higher LW ( = 0.009). A shorter interval between birth and first suckling of the litter was related to a higher CY ( < 0.01). The percentage of fat in colostrums was higher in Hypor sows (6.35 ± 0.51) than in PIC (4.98 ± 0.27; = 0.001), Topigs 20 (5.05 ± 0.14; < 0.001), and Danbred (5.34 ± 0.22; < 0.001) sows. The percentage of CF was negatively associated with parity ( = 0.02) and positively associated with the number of live-born piglets ( = 0.03). The percentages of colostral protein and lactose were not significantly associated with any factor in the multivariable model. In conclusion, this study demonstrated that CY and CF are affected by different sow and litter factors. Pig producers may implement these observations in their management to maximize production or reproduction potential by optimizing CI, CY, and CC.

Effect of mode of delivery on macronutrient content of breast milk

Objective: To determine the effect of delivery type on macronutrient content of colostral milk.Materials and methods: The study was conducted at Zekai Tahir Burak Maternity Teaching Hospital. Colostral milk samples from term lactating mothers who gave birth by vaginal or cesarean delivery (CD) were obtained on the 2nd postpartum day. Milk protein, fat, carbohydrate (CHO) and energy levels were measured by using a mid-infrared human milk analyzer.Results: A total of 204 term lactating mothers were recruited to the study; 111 mothers gave birth by vaginal route and 93 mothers by CD. Protein levels were statistically lower in colostral milk of mothers after CD compared to mothers who delivered vaginally (median 2.4 (range 0.3–6.4) g/dl versus 3 (0.5–6.3) g/dl, respectively; p = 0.036). Colostral fat, CHO and energy levels were similar between groups. In linear regression analysis, CD and maternal age were independently associated with lower protein content in colostrum.Conclusion: Vaginal delivery is associated with higher colostrum protein content. Hormonal activity induced by labor pain and uterine contractions might account for the alterations in the protein composition of human milk to facilitate optimal development of important physiologic functions in newborns.

Diagnostic value of cytokeratin 19, HBME-1, and galectin-3 immunostaining of cell block from fine-needle aspiration specimens in papillary carcinoma of the thyroid

This study determined the energy content and immunoglobulin G (IgG) concentration of Awassi ewe colostrum and examined the effects of parity and litter size on them. Colostral samples were collected from 57 ewes from the 1st to 7th parities with a litter size of 1 or 2, within 12 h after lambing. Concentrations of colostral fat, lactose, and protein were measured as energy sources, and IgG was measured as representative of the immunoglobulin content of the colostrum. Mean values obtained from analyses of the ewe colostrum samples were 7.4 ± 2.1 kJ/g for the energy value and 60.9 ± 21.4 mg/mL for IgG. Ewe parity did not influence colostral energy content, whereas the IgG concentration of the colostrum obtained from the primiparous ewes was higher than that from the multiparous ewes (P < 0.05). Among the multiparous ewes, the colostrum obtained from ewes carrying twins showed higher energy content and IgG concentrations than that from those carrying a single lamb (P < 0.05).

Effects of parity and litter size on the energy contents and immunoglobulin G concentrations of Awassi ewe colostrum

This study determined the energy content and immunoglobulin G (IgG) concentration of Awassi ewe colostrum and examined the effects of parity and litter size on them. Colostral samples were collected from 57 ewes from the 1st to 7th parities with a litter size of 1 or 2, within 12 h after lambing. Concentrations of colostral fat, lactose, and protein were measured as energy sources, and IgG was measured as representative of the immunoglobulin content of the colostrum. Mean values obtained from analyses of the ewe colostrum samples were 7.4 ± 2.1 kJ/g for the energy value and 60.9 ± 21.4 mg/mL for IgG. Ewe parity did not influence colostral energy content, whereas the IgG concentration of the colostrum obtained from the primiparous ewes was higher than that from the multiparous ewes (P < 0.05). Among the multiparous ewes, the colostrum obtained from ewes carrying twins showed higher energy content and IgG concentrations than that from those carrying a single lamb (P < 0.05).

Colostrum and milk production of sows is affected by dietary conjugated linoleic acid

The present experiment was conducted to investigate dietary effects of conjugated linoleic acid (CLA) on sow traits related to piglet survival and growth performance. A total of 23 gestating sows were fed either a standard lactation diet (control diet [CON]) or the CON supplemented with 1.3% CLA (cis-9, trans-11 and trans-10, cis-12) from day 108 of gestation until weaning (4 wk after parturition) to evaluate whether dietary CLA affects the yield and composition of colostrum, time for initiation of milk production, and sow milk yield. Sows fed CLA tended to produce more colostral fat (6.3 vs. 5.2%, respectively; P = 0.10) than CON sows whereas contents of lactose, protein, and dry matter were similar in the two groups. Sows fed CLA tended to produce less colostrum than CON sows (409 vs. 463 g/piglet, respectively; P = 0.07) as predicted by the piglet rate of gain from 0 to 24 h (58 vs. 97 g/piglet, respectively; P = 0.07). The piglet mortality during the first week of lactation tended to be higher for sows fed CLA than for CON sows (6.8 vs. 2.3%, respectively; P = 0.10), and the number of piglets that died or were moved to others sows to ensure survival during the first week was more than double in the CLA group (17.6 vs. 7.8%, respectively; P = 0.04). Copious milk production was initiated 33 h (CLA) and 34 h (CON) after parturition and was not affected by dietary treatments (P = 0.41). Sow milk yield was improved by the CLA treatment from days 7 to 14 of lactation (P = 0.03). Weight at birth (1.40 kg for both groups; P = 0.98) and at weaning [8.2 kg (CLA) and 8.0 kg (CON); P = 0.52] was not statistically different. In conclusion, colostrum yield was inhibited but milk yield was stimulated by dietary inclusion of cis-9, trans-11 and trans-10, cis-12 CLA and indicates that sow productivity may be improved by using different fatty acids for transition and lactating sows.

Effect of selenium supplementation and plane of nutrition on mares and their foals: Foaling data1

To investigate the maternal plane of nutrition and role of Se yeast on foaling variables and passive transfer of IgG, 28 Quarter Horse mares were used in a study with a randomized complete block design. Mares were blocked by expected foaling date and assigned randomly within block to dietary treatments. Dietary treatments were arranged as a 2 x 2 factorial with 2 planes of nutrition, pasture or pasture + grain mix (fed at 0.75% of BW on an as-fed basis) and 2 concentrations of Se yeast (0 or 0.3 mg/kg of DMI). This resulted in 4 treatments: pasture (PA), pasture + Se (PS), pasture + grain mix (PG), and pasture + grain mix + Se (PGS). Assuming DMI at 2% of BW, the mares fed PA and PS received approximately 100% of the calculated NRC (2007) DE requirements, whereas PG and PGS received 120%. Selenium supplementation began 110 d before the estimated foaling date, and all dietary treatments were terminated at parturition. At parturition, foaling variables were recorded. Additionally, placental weight was recorded and 2 samples from each placenta were collected for analysis of DNA, RNA, and protein. Colostrum was obtained for fat, protein, milk urea N, somatic cell count, and IgG analyses. Foal blood samples were collected at 0, 6, 12, 18, and 24 h after parturition for IgG analysis. There was no effect (P >or= 0.21) of Se or plane of nutrition on foaling variables; however, foal BW as a percentage of mare BW tended (P = 0.10) to be reduced in foals from mares on grain mix (PG and PGS; 7.6%) compared with mares not fed grain mix (PA and PS; 8.0%). There was also no effect (P >or= 0.20) of Se or plane of nutrition on placental cell number (mg of DNA/g), potential cellular activity (RNA:DNA), expulsion time, or weight. However, mares fed supplemental Se (PS and PGS) had decreased (P = 0.02) placental cell size (24.1 mg of protein/mg of DNA) compared with mares not fed supplemental Se (PA and PG; 32.5 mg of protein/mg of DNA). There was also no effect (P >or= 0.18) of Se or plane of nutrition on colostral fat, protein, milk urea N, or somatic cell count. However, mares fed grain mix (PG and PGS) had less (P = 0.03) colostral IgG (76.5 g/L) compared with mares not fed grain mix (PA and PS; 126.6 g/L). Foals from mares fed grain (PG and PGS) tended (P = 0.06) to have less overall serum IgG (13.6 g/L) compared with foals from mares not fed grain (PA and PS; 15.3 g/L). These data indicate that the maternal diet during the last one-third of gestation affects placental efficiency and colostral IgG.

Human proteome enhancement: high-recovery method and improved two-dimensional map of colostral fat globule membrane proteins.

The human milk fat globule membrane protein composition is still largely unknown, although it counts for 2-4% of the total milk protein content and contains several important biologically active components. The aim of this work was to create a two-dimensional electrophoresis (2-DE) map of the human milk fat globule membrane proteins, both integral and membrane-associated, and to identify and characterize as many protein components as possible. A new protocol for the solubilization and extraction of the human milk fat globule membrane proteins with a double extraction procedure is presented, and the results compared with the extraction methods reported in the literature. The proteins were separated, in the first dimension, by isoelectric focusing (IEF) in the pH range 3-10 on strips of 13 cm length and, in the second dimension, by Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) on 11.5% T homogeneous gels. A reproducible 2-DE map of integral and membrane-associated proteins was obtained and the first 23 spots, representing the major components, were identified by matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometric analysis and/or by amino acid sequencing.

Effect of fat content of colostrum on voluntary colostrum intake and fat utilization in newborn pigs.

The effects of colostral fat level on voluntary colostrum and ME intake were determined in 25 newborn pigs during the first postnatal day. Within a litter, five pigs were obtained before nursing and allotted on the basis of initial body weight (BW) at 2 h of age to one of the five treatments: killed or ad libitum bottle-fed sow colostrum containing 2.5, 5.0, 7.5, or 10.0% of total fat. A total of 24 feedings was provided at 60-min intervals, and pigs were killed 1 h after the final feeding. Total colostrum intake averaged 584.8 +/- 42 g (i.e., 436 g/kg of average BW) with the first two feedings accounting for 19.8% of the total consumption. Colostrum intake decreased linearly (P < .08) by 5.9 g/kg of average BW per 1% increase in the level of fat. However, GE and ME intake increased linearly (P < .01) by 7.65 and 4.09 kcal/kg average BW per 1.0 g/kg of average BW increase in fat intake, respectively. Adipose tissue lipoprotein lipase increased (P < .01) during the first postnatal day. Carcass fat deposition and fat oxidation increased linearly (P < .01) by .36 and .20 g/kg of average BW per 1.0 g/kg of average BW increase in fat intake, respectively. We suggest that increasing the fat content in colostrum has little effect on voluntary colostrum intake, and the practice may be an efficient method for improving the energy supply to newborn pigs.

Effects of induced or delayed parturition and supplemental dietary fat on colostrum and milk composition in sows2

Two experiments were conducted to evaluate the effects of inducing premature parturition on the composition of colostrum and milk and the effects of dietary fat supplementation on colostrum and milk composition from premature and delayed farrowing sows. In Trial 1, eight sows were allowed to farrow naturally (d 114, NF sows) and eight sows were induced to farrow (IF sows) prematurely by injection of prostaglandin F2 alpha on d 112 of gestation. Average fat content of sow's milk during the first 12 h postpartum was lower for IF than for NF sows (P < .05), as was overall mean fat percentage (P < .05). In Trial 2, 53 sows were randomly assigned in a 2 (diets) x 5 (parturition treatments) factorial experiment. Dietary treatments fed during the last 2 wk of gestation and throughout lactation were control diet and added fat diet (control diet plus 10% corn oil). Parturition treatments included 1) natural farrowing (d 114), induction of parturition with prostaglandin F2 alpha on 2) d 110, 3) d 111, or 4) d 112 of gestation, and 5) delay of parturition with progesterone followed by injection of prostaglandin on d 115. The added fat diet increased milk fat percentage compared with the control diet (P < .01). Colostral fat percentage was reduced by induction of premature farrowing (d 110 or 111) in sows fed the control diet but was unaffected in sows fed added dietary fat (interaction, P < .05). Mean fat content of colostrum was not reduced in groups receiving the added fat diet that were induced to farrow prematurely.(ABSTRACT TRUNCATED AT 250 WORDS)

The concentration of fat, protein and lactose in sows&amp;apos; colostrum from sucked and unsucked glands during lactogenesis II

The relationship between the changes in the composition of colostrum and the removal of colostrum from individual glands during lactogenesis II in the sow was investigated. Sequential samples of colostrum were collected from all mammary glands on six sows during the farrowing period, and the amount of colostrum removed from each gland was measured by weighing the piglets at 15 min intervals. Prior to farrowing, there were large between sow variations in colostral fat (c.v. 39.8%) and protein (c.v. 22.9%) compared with lactose (c.v. 9.5%), but less within sow variations for these components (&lt; 13.2%). From the commencement of farrowing, the sucked glands of all sows showed a significant increase in the concentration of colostral fat from 45.2 g/L to 76.1 g/L, but no consistent significant changes in the concentration of protein and lactose. The unsucked glands of all sows showed no consistent significant changes for fat, protein or lactose. Analysis of individual glands showed that 27 of the 34 sucked glands had a positive correlation between fat concentration and amount of colostrum removed. It was concluded that the withdrawal of colostrum from the mammary glands is an important component in the progressive increase in colostral fat during lactogenesis II in the sow.

Adaptation of fat metabolism to environmental temperature in the newborn pig

Susceptibility to cold is usually reported as a major factor involved in the neonatal mortality of piglets (English and Morrison, 1984). Low energy reserves and poor insulation largely contribute to the limited thermoregulatory capacities of the newborn pig (Mersmann, 1974; Curtis, 1974). Glycogen is the predominant source of energy accounting for about 0.6 of the total energy available at birth (Mellor and Cockburn, 1986) but glycogen stores are rapidly depleted after birth. In addition, the total body fat content is very low at birth, ranging from 10 to 20g/kg (Manners and McCrea, 1963). Whereas attempts made to increase the energy stored as fat in the newborn pig by manipulation of the sow diet during late gestation have given variable results (Seerley, 1984), colostrum has proved to be an efficient route for depositing fat and hence for the supply of energy to the piglet during the first postnatal day (Le Dividich, Esnault, Lynch, Hoo-Paris, Castex and Peiniau, 1991). The present study was designed to determine the effects of colostral fat level on the energy and fat metabolism of the newborn piglet when maintained during the 1st day of life at thermal neutrality (34°C) or in the cold (21°C).A total of 35 newborn Large White pigs averaging 1140 (s.e. 54) g in weight were used. Within each litter five piglets were selected according to their live weight. One was killed in order to determine the initial body composition. The remaining pigs were fitted with umbilical artery catheters and stomach tubes. They were placed in individual cages in closed temperature-controlled chambers maintained at either 34 or 21°C and were fed normal colostrum (60 g fat per kg, NFC) or a colostrum deprived of fat (&lt; 10 g fat per kg, LFC) at the rate of 15 to 18 g per meal per kg birth weight. A total of 24 meals were given at about 65-min intervals.

Effect of colostral fat level on fat deposition and plasma metabolites in the newborn pig.

The effects of colostral fat level on fat deposition and plasma concentrations of glucose, insulin, and free fatty acids (FFA) were determined in 28 newborn pigs during the first postnatal day. Soon after birth, pigs were allotted to four treatments groups. Group 1 was killed at birth. The remaining pigs were fed intragastrically sow colostrum that contained high (10.2%; HFC), normal (4.8%; NFC) or low (1.0%; LFC) levels of total fat at the rate of 15 to 18 g/kg birth weight at 65- to 70-min intervals. A total of 21 feedings was provided and pigs were killed 1 h after the last feeding. Body fat deposition increased linearly (P less than .01) with the amount of ingested fat by .32 (+/- .04) g per 1-g increase in fat intake. Fatty acid composition of the pigs changed toward that of the colostrum with increased fat in colostrum. More liver glycogen was lost (P less than .01) in pigs given LFC. Plasma concentrations of glucose and insulin were similar in pigs fed HFC and NFC. After the 11th feeding (14 h postnatal), LFC resulted in lower plasma glucose concentrations (P less than .05) than HFC or NFC. Plasma insulin concentrations also were lower in pigs fed LFC. Plasma FFA concentrations remained unchanged in pigs fed LFC but increased with both fat content in colostrum (P less than .05) and time (P less than .05) in the other two groups. Colostral fat plays a major role in the supply of energy and in glucose homeostasis in the neonatal pig.

Carbonyl Compounds in Cow and Buffalo Milk Fat

Cow and buffalo milk fat were analyzed for carbonyls over 1 yr to study the interrelationship among classes of carbonyls. Correlation between total carbonyls and ketoglycerides was positive. Monocarbonyl content of buffalo milk fat was higher than that of cow milk fat. Cow milk fat contained higher quantities (nearly twice) of β-ketoglycerides than buffalo milk fat. The percentage proportion of methyl ketones was much higher in cow than in buffalo milk fat. Colostral fat contained about 65 to 70% of carbonyls in normal milk fat. Monocarbonyls increased rapidly during the early period of lactation and gradually during the remaining period. However, ketoglycerides remained steady after a rapid increase during the early part of lactation.

Influence of stage of lactation on the triacylglycerol composition of buffalo milk fat.

Milk fats obtained from colostrum and early, middle and late lactation samples of buffalo milk were analyzed for their triacylglycerol (TG) compositions. Each milk fat was first separated by thin layer chromatography (TLC) into high, medium and low molecular weight TG. The TG fractions thus obtained were further segregated by argentation TLC, according to their degree of unsaturation into saturated, trans-monoene, cis-monoene, diene and polyene species. With progressive lactation, the major changes from colostral fat were an increase in lower fatty acids and decline in oleic acid. This caused, in turn, marked variations in saturated TG and diene TG and, to a smaller extent, in polyene TG. Monoene TG, both cis and trans, remained practically constant throughout. These trends were largely reversed toward the end of lactation.