Fat In Cattle Research Articles

Effect of lipid sources on fatty acid profiles of meat from pasture- and feedlot-finished Nellore bulls

We aimed to compare the influence of two lipid sources (soybean grain [SG], and protected fat [PF, Lactoplus], based on soybean oil) with a control diet (no lipid supplementation) on the fatty acid (FA) profile (longissimus muscle and subcutaneous fat) of beef cattle finished on grazing pasture or at a feedlot. The study was arranged in a complete randomized design, using 2 × 3 factorial scheme that combined 2 finishing systems and 3 diets. Seventy-eight young Nellore bulls (323.8 ± 25.4 kg body weight [BW] and 21 ± 3 months of age) were divided at random into two finishing systems: 1) pasture-finishing and 2) feedlot-finishing. The diet containing PF increased CLA in the muscle (P = 0.0002). Pasture-finished bulls fed lipid-supplemented diets had significantly more (P = < 0.0001) subcutaneous saturated fatty acids and polyunsaturated fatty acids (PUFA) in muscle, whereas the PUFA concentration of PF-fed bulls was highest (P = < 0.0001) in subcutaneous fat. The highest (P = 0.0090) concentration of Omega-6 (n6) was observed in the muscle tissue of pasture-finished animals supplemented with SG. However, the lowest concentration (P = 0.0010) of n6 FAs in subcutaneous fat was more evident in pasture-finished animals receiving the control diet. The concentration of C20:5 n3 (EPA) was significantly higher (P = 0.040) in the muscle tissue of animals receiving the control diet in pasture and deposition of EPA was greater (P = 0.0020) in the subcutaneous fat of pasture-finished animals. The highest concentrations (P = < 0.0001) of n3 were observed in the muscle tissue of pasture-finished animals. Animals receiving the control diet in both finishing systems had a lower (P = 0.0051) n6:n3 ratio in muscle tissue. By comparison, feedlot-finished animals showed a higher (P < 0.01) n6:n3 ratio in muscle tissue, and the highest (P = 0.0190) n6:n3 ratio in subcutaneous fat was observed in pasture- and feedlot-finished animals supplemented with PF compared to the control diet. The muscle and subcutaneous fat tissues of feedlot-finished bulls fed the control and SG diets had a significantly higher (P < 0.05) Δ9-desaturase C16 index. The lowest (P = 0.0010) elongase concentrations were observed in the muscle tissue of PF-fed bulls, regardless of finishing system. Overall, bulls finished on grazing pasture had a more desirable FA composition.

Association study between copy number variation and beef fatty acid profile of Nellore cattle.

The aim of this study was to analyze the association between the copy number variation regions (CNVRs) and fatty acid profile phenotypes for saturated (SFA), monosaturated (MUFA), polyunsaturated (PUFA), ω6 and ω3 fatty acids, PUFA/SFA and ω6/ω3 ratios, as well as for their sums, in Nellore cattle (Bos primigenius indicus). A total of 963 males were finished in feedlot and slaughtered with approximately 2years of age. Animals were genotyped with the BovineHD BeadChip (Illumina Inc., San Diego, CA, USA). The copy number variation (CNV) detection was performed using the PennCNV algorithm. Log R ratio (LRR) and allele B frequency (BAF) were used to estimate the CNVs. The association analyses were done using the CNVRuler software and applying a logistic regression model. The phenotype was adjusted using a linear model considering the fixed effects of contemporary group and the animal age at slaughter. The fatty acid profile was analyzed on samples of longissimus thoracis muscle using gas chromatography with a 100-m capillary column. For the association analysis, the adjusted phenotypic values were considered for the traits, while the data was adjusted for the effects of the farm and year of birth, management groups at birth, weaning, and superannuation. A total of 186 CNVRs were significant for SFA (43), MUFA (42), PUFA (66), and omega fatty acid (35) groups, totaling 278 known genes. On the basis of the results, several genes were associated with several fatty acids of different saturations. Olfactory receptor genes were associated with C12:0, C14:0, and C18:0 fatty acids. The SAMD8 and BSCL2 genes, both related to lipid metabolic process, were associated with C12:0. The RAPGEF6 gene was found to be associated with C18:2 cis-9 cis-12 n-6, and its function is related to regulation of GTPase activity. Among the results, we highlighted the olfactory receptor activity (GO:0004984), G-protein-coupled receptor activity (GO:0004930), potassium:proton antiporter activity (GO:0015386), sodium:proton antiporter activity (GO:0015385), and odorant-binding (GO:0005549) molecular functions. A large number of genes associated with fatty acid profile within the CNVRs were identified in this study. These findings must contribute to better elucidate the genetic mechanism underlying the fatty acid profile of intramuscular fat in Nellore cattle.

The effect of short/branched chain acyl-coenzyme A dehydrogenase gene on triglyceride synthesis of bovine mammary epithelial cells

Abstract. Short/branched chain acyl-CoA dehydrogenase (ACADSB) is a member of the acyl-CoA dehydrogenase family of enzymes that catalyze the dehydrogenation of acyl-CoA derivatives in the metabolism of fatty acids. Our previous transcriptome analysis in dairy cattle showed that ACADSB was differentially expressed and was associated with milk fat metabolism. The aim of this study was to elucidate the background of this differential expression and to evaluate the role of ACADSB as a candidate for fat metabolism in dairy cattle. After analysis of ACADSB mRNA abundance by qRT-PCR and Western blot, overexpression and RNA interference (RNAi) vectors of ACADSB gene were constructed and then transfected into bovine mammary epithelial cells (bMECs) to examine the effects of ACADSB on milk fat synthesis. The results showed that the ACADSB was differentially expressed in mammary tissue of low and high milk fat dairy cattle. Overexpression of ACADSB gene could significantly increase the level of intracellular triglyceride (TG), while ACADSB gene knockdown could significantly reduce the TG synthesis in bMECs. This study suggested that the ACADSB was important in TG synthesis in bMECs, and it could be a candidate gene to regulate the metabolism of milk fat in dairy cattle.

Estimation of genetic parameters that affect the fatty acid composition in intramuscular fat of Japanese Black cattle in Kagoshima

Estimation of genetic parameters that affect the fatty acid composition in intramuscular fat of Japanese Black cattle in Kagoshima

Association between FASN gene polymorphisms ultrasound carcass traits and intramuscular fat in Qinchuan cattle

Fatty acid synthase (FASN) is an enzyme involved with fat deposition and fatty acid composition in cattle. This study was conducted to detect single nucleotide polymorphisms (SNPs) of the FASN gene and explore their relationships with ultrasound carcass traits in order to assess the potential use of the FASN gene for the breeding selection of Qinchuan cattle for desirable carcass traits. The frequencies of SNP g.12740C>T, g.13192T>C and g.13232C>T were identified in 525 individual Qinchuan cattle which were also assessed for backfat depth, eye muscle area and intramuscular fat by ultrasound. According to the PIC values, g.13192T>C possessed an intermediate polymorphism (0.25<PIC<0.5). The SNPs of g.13232C>T, g.12740C>T possessed low polymorphism (PIC<0.25). Chi-square tests showed that g.13192T>C were in Hardy-Weinberg disequilibrium (c2<c0.052). Two SNPs were found to be associated with variation in ultrasound carcass traits. The H2H2 diplotypes had a greater back fat depth than H1H1, H1H4 and H1H2 (P<0.01). The TT genotype at g.13192T>C was associated with a greater eye muscle area and the TT genotype at g.13232C>T was associated with greater intramuscular fat. When these genotypes were combined there was no difference in eye muscle area and intramuscular fat between the diplotypes. The H2H2 diplotype was associated with carcass traits that are likely to provide economic advantage in Qinchuan cattle. Variations in the FASN genes and their corresponding genotypes may be considered as molecular markers for economic traits in cattle breeding.

Effects of silymarin (&lt;i&gt;Silybum marianum&lt;/i&gt;) supplementation on milk and blood parameters of dairy cattle

The present study was conducted to investigate the effect of dietary silymarin on milk yield, milk fat, and certain blood parameters of dairy cattle. Silymarin is a naturally accepted hepatoprotectant that is used in the treatment of liver diseases in human beings, and has been tested in dairy cows during peripartum. Animals are subject to subclinical fatty liver. In the first part of the study, the silymarin (20 g/head/day) was supplemented to dairy cattle rations in the last 21 days (peripartum) of pregnancy. In the second part of study, silymarin was added to the rations of Holstein dairy cows for three weeks postpartum. A total of 40 Holstein dairy cows at 2nd lactation with 550-600 kg live weight and average body condition score of 3.5 were used. Dairy cows were randomly separated into two treatment groups (20 cows in each). The first group was control (no addition) and the second group was treatment (silymarin supplemented) group. Treatments significantly increased milk yield, but decreased milk protein. Postpartum bodyweight loss was significantly less in the silymarin group than in the control group. Differences in postprandial plasma triglyceride (TRG) and total cholesterol (TC) levels were found to be significant. Plasma alanine aminotransferase (ALT) and total protein (TP) values of the groups were also significantly different. As a result, it was observed that silymarin supplementation of the ration did not have side effects, and peak milk yields could be achieved earlier with silymarin treatment. Application of silymarin is believed to be useful. It was also observed that silymarin treatments speeded up the metabolic adaptation process of the dairy cows at the beginning of lactation. It was suggested that silymarin should be used in transition periods of dairy cattle. Keywords : Body condition score, carsil, milk thistle, milk yield, peripartum,

THE EFFECTS OF CONCENTRATE FEED AND MINERAL BLOCK ON THE DENSITY LEVEL AND MILK FAT CONTENT OF DAIRY CATTLE

AbstractThe aim of this research is to understand the influence of concentrate feed and mineral block formulation on the densitylevel and milk fat of dairy cattle. The research was conducted on eight cross breed friesian holstein cows with ± 450 kg body weight and aged 2-4 years with milk production 8-11 liter/head/day. The experimental design of this study was complete randomized design with two treatments and each treatment was repeated four times. P0 (grass, tofu waste) and P1 (grass, tofu waste, concentrate feed, mineral block). The data was analyzed using t test (independent sample t test ). The software that was used to analyzed the data is Statistical Program for Social Science (SPSS) version 20 for Windows. The results showed that concentrate feed and mineral block did not significantly affect the density of milk and milk fat (p &gt; 0.05). The mean density of milk in the P0 was 1.0255 and P1 was 1.0253. Mean while the average milk fat in the P0 was 3.27% and in P1 was 3.45%. Keywords : concentrate, mineral block, density, fat, dairy cow

Identification of the bovine HSL gene expression profiles and its association with fatty acid composition and fat deposition traits

Hormone-sensitive lipase (HSL) is an intracellular neutral lipase capable of hydrolysing a variety of esters and is considered to be a candidate gene affecting fat deposition traits. Gene expression profiles of HSL were analysed in various adipose tissues of cattle, and the effect of HSL on lipid metabolism genes was analysed by a PCR array. Novel polymorphisms were identified within the HSL regulatory domain by sequencing, and the relationship between HSL variants and fat deposition traits was analysed. HSL mRNA was highly expressed in the subcutaneous and visceral fat of cattle. CPT1B/CPT1C and other lipocatabolic genes were upregulated, and lipogenesis-related genes (FASN, LPL and ACOT12) were downregulated by HSL overexpression in BFFs. Five novel variants in the HSL functional domain were significantly associated with fat deposition traits, including FCR, LBT, MFW and fatty acid composition. HSL plays a pivotal role in the regulation of lipolysis and fatty acid biosynthesis in beef cattle.

Increasing Energy Ration of Bali Cattle to Improve Digestible Nutrient, Milk Yield and Milk Quality

To determine the effect of energy levels on digestible nutrient, milk production and milk quality of 7 months pregnant Bali cattle, was the purpose of this study. The study was conducted in Bali, Province of Indonesia on 12 pregnant breeding phase of pre-calving (2 months before the birth) with the parent body weight 329-340 kg/head. The treatment given is four types of Metabolizable Energy (ME) levels: 2000, 2100, 2200 and 2300/kg respectively as treatment A, B, C, and D. All ration contain 10% of crude protein. Variables measured: energy intake, digestible nutrient, milk yield, and milk quality. This research is a randomized block design. The results showed that increase energy ration until 2300 kcal ME/kg would significantly (P&lt;0.05) increase energy intake and highest at cattle consumed ratio D is 22239.55 kcal/day. However, digestible nutrient was not affected. Milk production increased with increasing energy rations and highest (P&lt;0.05) at cattle received treatment D is 2179.83 ml/day compared to treatment A 936.67 ml/day. Milk fat and milk lactose also highest (P&lt;0.05) in treatment D are 8.56% and 4.76% respectively. Based on these results, it can be concluded that increase energy ration will increase energy intake, milk yield and milk fat and milk lactose of Bali cattle.

Genetic Variation in FABP4 and Evaluation of Its Effects on Beef Cattle Fat Content

ABSTRACTFABP4 is a protein primarily expressed in adipocytes and macrophages that plays a key role in fatty acid trafficking and lipid hydrolysis. FABP4 gene polymorphisms have been associated with meat quality traits in cattle, mostly in Asian breeds under feedlot conditions. The objectives of this work were to characterize FABP4 genetic variation in several worldwide cattle breeds and evaluate possible genotype effects on fat content in a pasture-fed crossbred (Angus-Hereford-Limousin) population. We re-sequenced 43 unrelated animals from nine cattle breeds (Angus, Brahman, Creole, Hereford, Holstein, Limousin, Nelore, Shorthorn, and Wagyu) and obtained 22 single nucleotide polymorphisms (SNPs) over 3,164 bp, including four novel polymorphisms. Haplotypes and linkage disequilibrium analyses showed a high variability. Five SNPs were selected to perform validation and association studies in our crossbred population. Four SNPs showed well-balanced allele frequencies (minor frequency > 0.159), and three showed no significant deviations from Hardy-Weinberg proportions. SNPs showed significant effects on backfat thickness and fatty acid composition (P < 0.05). The protein structure of one of the missense SNPs was analyzed to elucidate its possible effect on fat content in our studied population. Our results revealed a possible blockage of the fatty acid binding site by the missense mutation.

Effects of common dietary fatty acids on milk yield and concentrations of fat and fatty acids in dairy cattle

The objective of the present article was to summarise the effects of five common dietary fatty acids (C16:0, C18:0, C18:1, C18:2 and C18:3) on the major milk fat groups (&lt;C16, C16 and C18). Forty published papers were reviewed to evaluate the effect of adding free fat or oil supplements rich in C16 and C18 fatty acids on the response of milk fat secretion and composition. From those 40 studies, 21 were used to investigate the effect of total dietary concentration of C16:0, C18:0, C18:1, C18:2 and C18:3 on milk secretion or concentrations of milk &lt;C16, C16 and C18 fatty acid groups. The results indicated that C16 supplementation increased total milk fatty acids, mainly by increasing milk C16 yield, without affecting milk &lt;C16 and C18 yield. Supplements rich in unsaturated fatty acid decreased total milk fatty acid by inhibiting secretion of milk fatty acids shorter than C18, with linoleic acid being the most inhibitory. Mixtures of feed fatty acid (C16:0 + C18:0 and C16:0 + C18:1) did not significantly affect total milk fatty acid yield. According to regression of milk C16 yield on dietary fatty acid, endogenous C16 contributes ~80% of total milk C16, but this proportion varies with the level and type of dietary fatty acid fed. Milk mid-infrared analysis can be used to routinely measure the presence of milk &lt;C16 fatty acid, the concentration of which provides a good indicator of inhibition of milk fatty acid secretion. In contrast, measurement of total milk fat content is less effective as a diagnostic tool due to the masking effect of the exogenous supply of C16 and C18 dietary fatty acids.

0785 Muscle gene expression patterns associated with differential intramuscular fat in cattle and markers for skeletal muscle growth rate and major cell types

0785 Muscle gene expression patterns associated with differential intramuscular fat in cattle and markers for skeletal muscle growth rate and major cell types

0767 Vitamin C supplement increased intramuscular adipose tissues but not affect myogenic development of Hanwoo steers

Vitamin C (VC) supplements have been used for enhancing marbling fat in high-quality beef cattle. However, mode of action of vitamin C was not clearly studied for long time. The aim of this experiment was to determine the effect of additional saturated parm-oil coated VC supplement compare to a control diet (saturated parm-oil only) on the level of adipogenic and myogenic gene expressions at liver (LV), subcutaneous adipose tissue (SC), perirenal adipose tissue (PR), and longissimus dorsi muscle (LD). A 2 × 4 factorial arrangement (control, VC, and LV, SC, PR, and LD tissues) was used to feed 10 Hanwoo steers. Two steers were fed in same pen and 5 pens were used for treatment. Tissues were collected within 10 min of harvest for analysis of PPARγ, SCD, GLUT4, MHC1, MHC2X, and GPR43 mRNA abundance. Real-time RT-PCR was used to measure the quantity of respective mRNA relative to a ribosomal protein subunit 9 (RPS9) mRNA. Data were analyzed as a completely randomized design using the MIXED model. Difference between the control and treatments were determined using the LSD procedure. Overall ADG did not differ between VC supplement and the control (P > 0.05). Marbling score was greater in the VC treatment than in the control (P < 0.05). Lipid percentage tended to greater (P = 0.084) in the VC treatment but share force tended to be lower in the VC treatment (P = 0.068). Real-time quantitative PCR revealed that the mRNA content of SCD in PR from VC supplement cattle increased (P < 0.05) compared with the control. There was no mRNA effect at MUS in cattle. However, mRNA level of GLUT4 and GPR43 were increased at LV tissues in VC-treated cattle (P > 0.05). These data indicated that VC supplement increased relative mRNA level of GLUT4 and SCD in SC and LV tissue but not affect myogenic gene expression on final fattening periods of Hanwoo steers.

Fatty acid profile, carcass traits and meat quality of Nellore steers following supplementation with various lipid sources

The aim of the present study was to evaluate the fatty acid composition of meat and subcutaneous fat, carcass traits and meat quality of Nellore steers fed diets supplemented with various lipid sources. Forty-five young bulls, with average bodyweight of 441 ± 30 kg, were allotted into 10 paddocks, with five treatments, each consisting of two paddocks. The bulls were randomly assigned into one of the following five treatments, which consisted of four lipid sources: palm oil (PO), linseed oil, rumen protected fat (soybean-based oil), whole soybean, and a control (without additional fat). Trial duration was 120 days, which included 30 days of adaptation. Supplements were offered daily at 10 g/kg bodyweight per day. Dietary supplements for providing additional fat were formulated to consist of 10% ether extract. Lipid sources did not significantly affect the average daily gain (P = 0.797) or dressing percentage (P = 0.663). Supplementation with PO increased the concentrations of lauric acid (P = 0.036) and myristic acid (P &lt; 0.001) in the muscle and subcutaneous fat. Animals supplemented with linseed oil had significantly higher concentrations of conjugated linolenic acid in the meat (P = 0.036) and fat (P = 0.049) than did control animals. In the present study, the use of various lipid sources in dietary supplements of grazing cattle during finishing period did not affect carcass traits or physical attributes of beef. This absence of statistical significance may be related to the minimum number of repeat paddocks (2) per treatment. Thus, differences that can have a practical significance were not evidenced by statistical analysis. The inclusion of PO and protected fatty acids derived from soybean oil (rumen-protected fat) is not recommended as a method to improve the lipid profile of meat and subcutaneous fat of Nellore cattle.

The Brazilian strategy for monitoring persistent organic pollutants in food obtained from animals

The implementation of quality control procedures in analytical laboratories around the world has become essential in order to ensure the quality and safety of food. This article describes the procedure adopted by the Brazilian government in order to achieve this goal, specifically in the area of analysis of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). The validation of a multiresidue method, the calculation of measurement uncertainty, and the quality control procedure adopted in the determination of these compounds in beef cattle fat were performed as set out in national legislation (Brasil, 2011), which is aligned with international guidelines. Evaluation was made of selectivity, linearity, precision (repeatability and reproducibility), accuracy, and limits of detection and quantification. Stability studies were also undertaken. The technique was extended to three other matrices (poultry, horse, and pig adipose tissues), with evaluation of matrix effects, selectivity, linearity, and accuracy. The analyses were performed by gas chromatography with electron capture detection (GC-ECD) and mass spectrometric detection (GC–MS). In recent years, analyses conducted under the National Plan for Control of Residues and Contaminants (PNCRC) have shown no exceedances of the maximum permitted residue levels (MRLs) of pesticides and PCBs in these tissues, as observed in other countries that carry out effective monitoring of these contaminants.

Nutrigenomics and Beef Quality: A Review about Lipogenesis.

The objective of the present review is to discuss the results of published studies that show how nutrition affects the expression of genes involved in lipid metabolism and how diet manipulation might change marbling and composition of fat in beef. Several key points in the synthesis of fat in cattle take place at the molecular level, and the association of nutritional factors with the modulation of this metabolism is one of the recent targets of nutrigenomic research. Within this context, special attention has been paid to the study of nuclear receptors associated with fatty acid metabolism. Among the transcription factors involved in lipid metabolism, the peroxisome proliferator-activated receptors (PPARs) and sterol regulatory element-binding proteins (SREBPs) stand out. The mRNA synthesis of these transcription factors is regulated by nutrients, and their metabolic action might be potentiated by diet components and change lipogenesis in muscle. Among the options for dietary manipulation with the objective to modulate lipogenesis, the use of different sources of polyunsaturated fatty acids, starch concentrations, forage ratios and vitamins stand out. Therefore, special care must be exercised in feedlot feed management, mainly when the goal is to produce high marbling beef.

Estimation of variance components of milk, fat, and protein yields of Tunisian Holstein dairy cattle using Bayesian and REML methods

Abstract. A multi-trait repeatability animal model under restricted maximum likelihood (REML) and Bayesian methods was used to estimate genetic parameters of milk, fat, and protein yields in Tunisian Holstein cows. The estimates of heritability for milk, fat, and protein yields from the REML procedure were 0.21 ± 0.05, 0.159 ± 0.04, and 0.158 ± 0.04, respectively. The corresponding results from the Bayesian procedure were 0.273 ± 0.02, 0.198 ± 0.01, and 0.187 ± 0.01. Heritability estimates tended to be larger via the Bayesian than those obtained by the REML method. Genetic and permanent environmental variances estimated by REML were smaller than those obtained by the Bayesian analysis. Inversely, REML estimates of the residual variances were larger than Bayesian estimates. Genetic and permanent correlation estimates were on the other hand comparable by both REML and Bayesian methods with permanent environmental being larger than genetic correlations. Results from this study confirm previous reports on genetic parameters for milk traits in Tunisian Holsteins and suggest that a multi-trait approach can be an alternative for implementing a routine genetic evaluation of the Tunisian dairy cattle population.

Effect of β-carotene supplementation on the expression of lipid metabolism-related genes and the deposition of back fat in beef cattle

To evaluate the effects of β-carotene (βC) supplementation on lipid metabolism in the back fat of beef cattle, 120 continental crossbred (Simmental × local Luxi yellow cattle) steers were selected randomly from feedlots and allotted to four groups. Each steer was supplemented with 0, 600, 1200, or 1800 mg/day of βC for 90 days, and then received no βC for 60 days (depletion period). The βC levels significantly increased in steers supplemented with βC (P &lt; 0.01), and then decreased to the control level by Day 150. Back fat thickness decreased slightly with increasing βC supplementation, and significantly differed among groups after supplementation ceased (P &lt; 0.01 on Day 120, P &lt; 0.05 on Day 150). Significant regression relationships between βC supplement level and both βC content in back fat tissue on Day 90 and back fat thickness on Days 90, 120, and 150 were established (P &lt; 0.01). No significant differences in the dry matter intake or average daily gain were detected, but higher net meat percentages were observed in the 1200 and 1800 mg/day βC-supplemented groups compared with the control (P &lt; 0.05). The mRNA expression of two fat synthesis-related genes, acetyl-CoA carboxylase and fatty acid synthase, were downregulated during the supplementation period, but upregulated during the next 60 days when the steers received no βC supplementation. In contrast, the expression of two fat hydrolysis-related genes, hormone-sensitive lipase and adipose triglyceride lipase, were upregulated during the supplementation period and downregulated in the subsequent 60 days. The results showed that βC supplementation suppresses back fat deposition in beef cattle by inhibiting fat synthesis and enhancing fat hydrolysis.

Genetic analysis of carcass traits in beef cattle using random regression models.

Livestock mature at different rates depending, in part, on their genetic merit; therefore, the optimal age at slaughter for progeny of certain sires may differ. The objective of the present study was to examine sire-level genetic profiles for carcass weight, carcass conformation, and carcass fat in cattle of multiple beef and dairy breeds, including crossbreeds. Slaughter records from 126,214 heifers and 124,641 steers aged between 360 and 1,200 d and from 86,089 young bulls aged between 360 and 720 d were used in the analysis; animals were from 15,127 sires. Variance components for each trait across age at slaughter were generated using sire random regression models that included quadratic polynomials for fixed and random effects; heterogeneous residual variances were assumed across ages. Heritability estimates across genders ranged from 0.08 (±0.02) to 0.34 (±0.02) for carcass weight, from 0.24 (±0.02) to 0.42 (±0.01) for conformation, and from 0.16 (±0.03) to 0.40 (±0.02) for fat score. Genetic correlations within each trait across ages weakened as the interval between ages compared lengthened but were all >0.64, suggesting a similar genetic background for each trait across different ages. Eigenvalues and eigenfunctions of the additive genetic covariance matrix revealed genetic variability among animals in their growth profiles for carcass traits, although most of the genetic variability was associated with the height of the growth profile. At the same age, a positive genetic correlation (0.60 to 0.78; SE ranged from 0.01 to 0.04) existed between carcass weight and conformation, whereas negative genetic correlations existed between fatness and both conformation (-0.46 to 0.08; SE ranged from 0.02 to 0.09) and carcass weight (-0.48 to -0.16; SE ranged from 0.02 to 0.14) at the same age. The estimated genetic parameters in the present study indicate genetic variability in the growth trajectory in cattle, which can be exploited through breeding programs and used in decision support tools.

Headspace: An Interview with Roman Kaiser

HeadspaceAn Interview with Roman Kaiser Roman Kaiser (bio) Click for larger view View full resolution 1. Roman Kaiser on the skimmer above the rainforest of French Guiana. Photograph by Kent Lombard. [End Page i] “Headspace” is a chemist’s and perfumer’s expression. It refers to the volume that an olfactory object, be it a flower or trash, occupies with its diffusing scent. It is, therefore, a spatial term, albeit a space that changes size and shape depending on heat, humidity, and the direction of the breeze. “Headspace” also refers to a cluster of technologies—namely a mixture of adsorption techniques, capillary gas chromatography, and mass spectrometry—that allow the sampling and identification of olfactants. The techniques of headspace were pioneered in the 1970s by scientists working in the flavors and fragrances industry. By the 1990s, the technology was ubiquitous in industry, and thereafter appeared in the practice of artists. Roman Kaiser was a major figure in the development of headspace techniques, refining the technology in a decades-long study of the fragrances produced by rare plants as orchids studied in situ in rainforest canopies—species that he reached on occasion via a net suspended from an airship. The study of a single flower would typically yield two hundred micrograms of aroma, and so Kaiser might come back from such an expedition with a total of 5 milligrams of material to show for the effort, enough to keep him busy in the lab for six to nine months. Kaiser was also a prolific consultant in perfume design, and his influence is still to be detected, in some form or another, in a not-insignificant proportion of commercial scents on the market today. FUTURE ANTERIOR: On the prehistory, and the history, of the headspace method . . . ROMAN KAISER: In the beginning, so to speak, there was Nymphaea caerulea, the so-called blue lotus of Egypt, as well as henna and other attractively scented plants. The blue lotus in particular was the holiest flower in ancient Egypt, and its scent was highly desirable. Fragrances had a major role in ancient Egyptian culture. In the pyramids they found documentation of perfume recipes. In order to extract its aroma, it was laid in the fat of cattle. When the fat was saturated, one removed the remains of the plants, and the fat became hard again. One worked the aromatic fat into conical shapes and placed it upon the head. The triangles that you see on the heads of figures in Pharaonic paintings were perfume dispensers. In [End Page 1] the eighteenth and nineteenth century these ancient techniques were revisited for highly valued scents such as those of tuberose, narcissus, and jasmine, in particular in the French city of Grasse. One laid the flowers in frameworks charged with purified bovine fat. The fat adsorbs the smell, just as when you leave uncovered butter in the fridge and it adsorbs aromas. This extracting technique is not used any more, it’s simply too onerous. The headspace technique is, in principle, quite similar, only not destructive. Fat adsorption still requires plucking the flowers. But headspace was from the beginning intended to be essentially a nondestructive process. Historically speaking, classical analytical methods tend to be destructive, but it’s a feature of contemporary techniques is that we can conduct nondestructive analysis. This is for a very good reason, in this case, for one then has access to the rarest of plants. Instead of bovine fat, one places a highly adsorbent carrier material in this small glass tube that collects traces of olfactants. With headspace, one has to customize the method to the plant. One has to pay close attention that the plant does not suffer, as it might then produce metabolites associated with stress. Normally, in analysis, one tries to completely standardize the methodology, but that is not entirely possible here. For instance, one has to consider at what time of day the flower gives off its scent. Some flowers are only fragrant in the morning, others at midday, others overnight. There are flowers that are described by botanists as “un-scented” because they have studied them at the wrong time of day. I have discovered about eight...