Tissue weights and body composition of two genetic lines of barrows and gilts from twenty to one hundred twenty-five kilograms of body weight

Barrows and gilts of 2 genetic lines with differing lean gain potentials (high-lean = 375 g of fat-free lean/d; low-lean = 280 g of fat-free lean/d) were used to determine tissue and organ weights and compositions from 20 to 125 kg of BW. The experiment was a 2 (genetic line) x 2 (sex) x 5 (BW) factorial arrangement of treatments in a completely randomized design conducted with 2 groups of pigs in 6 replicates (n = 120 pigs). Six pigs from each sex and genetic line were slaughtered at 20 kg of BW and at 25 kg of BW intervals to 125 kg of BW. At slaughter, the internal tissues and organs were weighed. Loin and ham muscles were dissected from the carcass and trimmed of skin and external fat, and the ham was deboned. Residuals from the loin and ham were combined with the remaining carcass. Body components were ground, and their compositions were determined. The results demonstrated that tissue weights increased (P < 0.01) as BW increased. Loin and ham muscle weights increased but at a greater rate in the high-lean line and in gilts resulting in genetic line x BW and sex x BW interactions (P < 0.01). Liver and heart expressed on a BW or a percentage of empty BW basis increased at a greater rate in the high-lean line resulting in a genetic line x BW interaction (P < 0.01). Liver and intestinal tract weights were heavier in barrows than in gilts, significant only at 45 (P < 0.05), 75 (P < 0.01), and 100 (P < 0.05) kg of BW. Loin and ham muscles from the high-lean genetic line and gilts had greater (P < 0.01) water, protein, and ash contents compared with the low-lean genetic line and barrows resulting in genetic line x BW and sex x BW interactions (P < 0.01). The remaining carcass (minus loin and ham muscles) had greater (P < 0.01) amounts of water and protein, and less (P < 0.01) fat in the high-lean genetic line and gilts. The high-lean genetic line and gilts had more total body water, protein, and ash, but less body fat, with these differences diverging as BW increased, resulting in a genetic line x BW interaction (P < 0.01). The results indicated that liver and heart weights were greater in high-lean pigs, reflecting the greater amino acid metabolism, whereas the liver and intestinal tract weights were greater in barrow than gilts, reflecting their greater feed intakes and metabolism of total nutrients consumed.     

Growth of protein, moisture, lipid, and ash of two genetic lines of barrows and gilts from twenty to one hundred twenty-five kilograms of body weight

Two genetic lines of barrows and gilts with different lean growth rates were used to determine the BW and chemical composition growth from 23 to 125 kg of BW. The experiment was a 2 x 2 x 5 factorial arrangement of treatments in a completely randomized design conducted in 2 replicates. Six pigs from each sex and genetic line were killed at approximately 25-kg intervals from 23 kg to 125 kg of BW. At slaughter, tissues were collected and weighed. All components were ground and frozen until analyzed for water, protein, lipid, and ash. Serial BW data were fitted to alternative functions of day of age. Based on Akaike's information criteria values, the random effects model, BW(i, t) = (1 + c(i))(b(0) + b(1)t + b(2)t(2)), was the best mixed model equation. The chemical component mass data were fitted to alternative functions of BW. The allometric function, chemical component mass = aBW(b), provided the best fit to the data. Daily deposition rates of each chemical component were predicted by using the derivatives of the 2 functions. The overall ADG of the 2 genetic lines were not different. Barrows had 0.052 kg/d greater (P = 0.03) ADG than gilts. Allometric growth coefficients for all 4 chemical components were different (P < 0.01) for each genetic line. Allometric coefficients and predicted relative growth (g/kg of BW gain) for protein and moisture mass were greater (P < 0.01) for the high lean-gain pigs than the low lean-gain pigs. Allometric coefficients for lipid mass were smaller (P = 0.001) for the high lean-gain pigs than the low lean-gain pigs overall. Allometric coefficients and predicted relative growth rates for lipid mass were greater (P < 0.01) and for moisture and protein mass were lesser (P < 0.002) than the gilts. Compared with low lean-gain pigs, high lean-gain pigs had (1) 32.8% lesser predicted daily rates of lipid deposition (200 vs. 305 +/- 80 g/d), with the difference increasing from 23 to 37% from 25 to 125 kg of BW; (2) 12.3% greater daily rates of protein deposition (118.7 vs. 106.0 +/- 3.3 g/d); and (3) 18.8% greater predicted daily moisture accretion rates (423 vs. 356 +/- 9 g/d). Overall, barrows had 21.3% greater lipid deposition (279 vs. 230 +/- 78.2 g/d) than gilts. In this study, barrows and gilts had similar predicted daily moisture, protein, and ash accretion rates.     

Body composition of breeding gilts in response to dietary protein and energy balance from thirty kilograms of body weight to completion of first parity

The relationships among BW, backfat depth, and body physical and chemical composition were evaluated in response to dietary protein and DE balance in breeding gilts from 30 kg of BW to weaning of the first litter. Large White (sire) x Landrace (dam) F1 hybrid (White; n = 75) and Landrace (sire) x (Meishan x Large White; dam) (Meishan; n = 19) hybrid gilts were received at 30 kg of BW. Five gilts were taken as the initial slaughter group at 30 kg of BW, and the remaining gilts were fed diets differing in total lysine to DE ratio, high (H) vs. low (L), from 30 kg of BW to mating (rearing), and during gestation and lactation, allowing factorial investigation of dietary treatment effects and interactions during rearing, gestation, and lactation. Gilts were slaughtered at approximately 50 and 90 kg of BW, and at mating, farrowing, and weaning. Gilts fed L diets during rearing were lighter at mating (117.9 vs. 133.6 kg of BW, P = 0.035) due to a reduction in gain (592 vs. 720 g/d, P = 0.002) and a restriction in protein accretion (83 vs. 117 g/d, P = 0.001). During rearing, lipid accretion did not differ between L- and H-fed gilts (208 vs. 198 g/d, P = 0.60), but the ratio of lipid to protein accretion was about 1.5-fold greater in L-fed gilts, where lipid mass expressed as a percentage of BW was increased at mating (26.0 vs. 21.9%, P = 0.005). Effects of L diets on lipid accretion during rearing were transient; no residual effects on body lipid mass (P > 0.17) were found at farrowing or weaning. Overall, Meishan hybrids carried greater lipid mass (P < 0.001) than White hybrid gilts. Whereas the rate of body lipid and protein accretion and body lipid and protein mass can be nutritionally influenced and can vary according to growth stage, reproductive status, and genotype, this study established that body protein mass expressed as a proportion of the lipid free empty BW remains inflexible. A value for this measure of 0.188 +/- 0.0052 was found in White and Meishan hybrid gilts ranging from 28 to 203 kg of BW and 3 to 36 mm backfat depth, covering growth, pregnancy, and lactation, and offered diets differing in protein and energy balance. Body protein mass can be predicted as approximately 0.2 of the lipid free empty BW once body lipid mass is estimated accurately from physical measurements, such as backfat depth (P2, mm) and BW (kg), by regression using lipid (kg) = - 8.14 (SE, 1.302) + 0.167 (SE, 0.010) BW + 0.883 (SE, 0.065) P2 (residual SD = 3.51; R2 = 0.912).     

Characterization of muscles from boars, barrows, and gilts slaughtered at 100 or 110 kilograms: differences in fat, moisture, color, water-holding capacity, and collagen.

For characterization of ether-extractable fat content (EE), L*, a*, and b* color, and water-holding capacity (WHC), 12 muscles or muscle groups were dissected from 48 pork carcasses of boars, barrows, or gilts that were fed diets either at minimum (LO) or 1% above (HI) their protein requirements and slaughtered in two separate trials at 100 or 110 kg. In both trials across muscles, gilts and boars had lower (P < .05) EE than barrows. In the 110-kg trial, boars had lower (P < .001) EE than gilts. In the 100-kg trial, boars on LO diets had lower (P < .001) WHC than all other groups, and both boar groups had lower (P < .05) WHC than gilts. No differences (P > .05) in WHC were seen in the 110-kg trial. In the 100-kg trial, gilts had lower L* (P < .05) than boars and barrows, but in the 110-kg trial boars had lower L* (P < .05) than barrows and gilts. The lowest (P < .05) a* values were for boars in the 100-kg trial and for boars on LO diets in the 110-kg trial. In both trials, the serratus ventralis had more (P < .001) EE than all other muscles. In both trials, the semitendinosus had higher (P < .001) L* and the longissimus had lower (P < .01) a* and b* than all other muscles. The numerous differences observed among muscles may help identify optimal uses for the entire pork carcass.     

Prolonged feeding of high dietary levels of organic and inorganic selenium to gilts from 25 kg body weight through one parity

An experiment evaluated the selenosis effects from feeding high dietary Se levels of organic or inorganic Se sources to growing gilts with the dietary treatments continued through a reproductive cycle. A total of 88 gilts were allotted at 25 kg BW to two replicates in a 2 x 4 factorial arrangement in a randomized complete block design. Inorganic Se (sodium selenite) or organic (Se-enriched yeast) Se were added to diets at 0.3, 3, 7, or 10 ppm Se. At 105 kg BW, four gilts per treatment were killed and livers collected for Se analysis. At 8 mo of age, three gilts from each treatment group were bred and fed their treatment diet, with subsequent reproductive performance and selenosis effects evaluated. Serum collected at various intervals in gilts, sows, and progeny measured glutathione peroxidase activity and Se concentrations. Sow colostrum and milk was analyzed for their Se concentrations. Three pigs per treatment were killed before colostrum consumption and at weaning (14 d) and tissue collected for Se analysis. Gilt gains (P < 0.01) and feed intakes (P < 0.05) declined during the grower period as dietary Se level increased for both Se sources. Serum and liver Se concentrations increased as dietary Se level increased and was higher when organic Se was fed (P < 0.01). Sows fed dietary Se levels at > 7 ppm had lower gestation weights (P < 0.05) and lower lactation feed intakes (P < 0.05). As Se level increased, sows fed organic Se had a lower number of live pigs born (P < 0.05) and weaned fewer pigs (P < 0.05) with lower litter gains (P < 0.05) than did sows fed inorganic Se. Colostrum and milk Se concentrations increased as dietary Se levels increased particularly when organic Se was fed (P < 0.01). Neonatal and weanling pig tissue Se and serum Se concentrations increased as dietary Se level increased and when organic Se was fed, resulting in interaction responses (P < 0.01). Pigs nursing sows fed > 7 ppm inorganic Se had hoof separation and alopecia, with the severity being greater when sows were fed the inorganic Se source. These results suggest that both the organic and inorganic Se sources were toxic when fed at 7 to 10 ppm for a prolonged period, but organic Se seemed to express the selenotic effects more on reproductive performance, whereas inorganic Se was more detrimental during lactation.     

Relationship of body measurements and body condition score to body weight in modern Finnish Ayrshire cows

Abstract

The differences in body weight (BW) and measurements between the cows of today and the early 70s was evaluated and the usefulness of heart girth (HG), wither height, body length (BL) and body condition score (BCS) as predictors of the BW of modern Finnish Ayrshire cows was estimated. During the last three decades, the BW, HG and BL has increased indicating change in body conformation. The BW prediction equation based on early 70s data underestimate the BW of modern Ayrshire cows. Based on current data it is recommended to use different models to predict BW for primiparous and multiparous cows. From single measurements, HG predicted BW most accurately. Inclusion of BL in model gave slight improve in BW prediction, especially for primiparous cows. An additional term of age or days in milk (DIM) for primiparous cows and BCS or DIM for multiparous cows along with HG increased slightly the accuracy of BW prediction.     

Relationship between body fatness,ovarian structure and reproduction in mature females from lines of genetically lean or fat broilers given different food allowances

1. Reproductive and other characteristics were measured at 34 and 60 weeks of age in broiler breeder hens on 6 different feeding regimes. The hens came from genetically lean and fat lines selected on the basis of low or high 7‐week plasma very low density lipoprotein (VLDL) concentration.

2. Plasma VLDL concentrations were consistently higher at all ages in fat line hens but were not affected by dietary treatment.

3. Mature body weight did not differ between the lines in birds fed ad libitum but with food restriction throughout life, fat line birds were lighter at 34 weeks.

4. There was little difference between the lines in abdominal fatness of birds fed ad libitum up to 60 weeks. Fat line birds were always fatter than lean line counterparts under food restriction.

5. Egg production was higher in lean line birds fed ad libitum but food restriction improved egg production in both lines. Peak egg productions were similar in both lines but there was evidence that the optimal food allowances for egg production was higher in the lean compared with the fat line.

6. Ovarian yellow follicle numbers were highest at 34 weeks in ad libitum fed lean line birds and declined linearly with decreasing body weight caused by food restriction but there was no such relationship in fat line birds.

7. White follicle numbers were higher and follicular atresia was lower in the lean line.

8. It is concluded that poor reproduction in fat line birds was associated with inhibition of follicular development and atresia rather than by high plasma VLDL concentrations promoting excessive yolk formation.     

湖羊不同阶段体重遗传参数与育种值估计及其与饲料效率性状的遗传相关

本研究旨在通过优化普通动物模型估计湖羊生长性状遗传参数,为湖羊选育提供参考.选取系谱记录完整的初生湖羊公羔,称取初生重、断奶重、100 d和180 d体重,并采用单栏测定100～180 d的采食量,通过ASReml-R软件利用约束最大似然法(REML)对遗传参数进行估计,利用最佳线性无偏估计法(BLUP)估算各阶段体重...     

Biochemical,physiological and production indices related to fat metabolism in the laying fowl at various stages of physiological development

1. The significance of fat accumulation during physiological development of layers was studied using White Leghorn x Australorp pullets from 12 weeks of age.

2. Liver fat, carcass fat, liver weight and body weight increased markedly at the onset of sexual maturity.

3. Within the liver, the protein to DNA ratio did not alter significantly during development; glycogen was not consistently depleted by egg production.

4. Liver fat content was significantly correlated with carcass fat, liver weight and DNA concentration, and plasma total lipid and cholesterol, independent of stage of development; with body weight, liver protein, moisture, and protein to DNA ratio, excluding the period prior to commencement of sexual maturation; and with plasma phospholipid during lay.

5. Obesity was a feature of faster growing fowls which matured earlier, consumed more, utilised food less efficiently for egg production and produced fewer saleable eggs.     

Estimates of environmental effects and genetic parameters for body measurements and weight in Brahman cattle raised in Mexico

A Derivative Free Restricted Maximum Likelihood (DFREML) algorithm was used with single trait and two traits animal models to estimate the variance and covariance components and thus, heritabilities and phenotypic, genetic and environmental correlations among nine different body measurements and weights of Brahman cattle raised in Mexico. The following measurements were considered: hip width, pin width, hip‐pin width, anterior height, posterior height, body length, thorax perimeter, scrotal circumference and weight. The analysis was based on a total of 1018 animals, born between 1992 and 1995, from 17 herds in the Mexican States of Chiapas, San Luis Potosi, Tabasco, Tamaulipas and Veracruz. The model included the following fixed effects: herd, year‐season of birth, sex, age of the animal and feed management. The only random effect was the direct additive genetic contribution of each animal. All fixed effects in the model were significant for all traits (p < 0.05). Estimated heritabilities for the traits were: hip width 0.57, pin width 0.32, hip‐pin width 0.41, anterior height 0.56, posterior height 0.54, body length 0.32, thorax perimeter 0.49, scrotal circumference 0.02 and weight 0.66. The magnitude of the heritabilities was medium to high, with the exception of scrotal circumference. The genetic correlations among all body measurements were consistently positive and high, ranging from 0.64 to 1.00. Although other measures showed higher genetic correlations with weight, thorax perimeter combines a high value (0.70) with ease and repeatability, making it a useful field measurement to estimate body weight when scales are not available.     

Heterosis in body weight related to growth performance of parental lines of Japanese quail and to heterosis in lay

1. Three outbred lines of Japanese quail and their reciprocal crosses were used. The lines differed in mature body weight or in the shape of the growth curve. Growth was described by body weight (BW) at 0, 4, 7, 14, 21, 28, 35, 42, 48, 56, 63 and 70 d of age and expressed by the parameters of Richards' function. Dickerson's model was used to estimate direct genetic, maternal genetic and direct heterotic effects. 2. The magnitude of BW heterosis was not constant during postnatal growth, it showed a different curvilinear age-trend for each hybrid combination. 3. The age-trend of BW heterosis resulted from the change of the shape of the growth curve. 4. The age-trend of BW heterosis and its maximum magnitude were associated with differences in the growth pattern of parental lines. 5. The heterosis at the inflection point was accompanied by heterosis in egg number.     

Phenotypic and genetic variation in body weight,food intake and energy utilisation in Hereford cattle II. Effects of age and length of performance test

The effects of length of test, age when evaluations are made, and correction of data for body weightat the start of test on genetic and phenotypic parameters describing performance test results in beef cattle were studied. The data consisted of body weight, food intake and carcass composition measurements on 542 Hereford bull calves, from 200 to 400 days of age. The traits studied included weights at various ages, weight gain, lean growth rate, food intake, food conversion ratio, lean food conversion ratio, food intake in relation to metabolic body weight, energy required for protein and fat deposition, and predicted maintenance expenditure. Traits were derived for the whole test as well as for part test periods of 200–300 days and 300–400 days.Heritabilities for all traits, except those describing weight at a given age, were lower for the 300–400-day period than for either the 200–300-day period or the whole test. Correlations, however, were higher between whole test and 300–400-day traits than between whole test and 200–300-day traits. Phenotypic correlations between the same trait measured in the two-part test period were very low and much lower than the genetic correlations. Corrections for body weight at the start of test had only a trivial effect on the heritabilities of all traits, the relationships between traits and potential genetic progress in traits measured during the test.     

Responses of body composition, growth and food efficiency to dietary protein in genetically lean and fat broilers up to seven weeks of age

1. Growth, food intake and abdominal fatness were measured at 7 weeks of age in male and female broilers from genetically lean and fat lines fed on isoenergetic diets containing 160, 190, 210, 230 and 260 g crude protein/kg from hatching. 2. The mean proportions of abdominal fat decreased from 39 to 20 g/kg body weight in the fat line and from 26 to 11 g/kg in the lean line over this range of protein concentrations. 3. Protein requirements, for optimum growth as a proportion of the diet did not differ between the lines but the lean line was less tolerant of inadequate dietary protein. 4. In birds fed on the same diet, conversion efficiencies of food (FCE) and dietary protein (PCE) were always superior in the lean line but energetic efficiency (EE) was similar in good growing birds of both lines. 5. When dietary protein was adequate for growth and body compositions were equalised in the two lines (by feeding higher protein diets to the fat line), lean line birds had 10% better FCE, 6% better EE and 33% better PCE. 6. It is concluded that genetic selection is a more effective and economic means of producing leaner broilers than dietary manipulation.     

Mandible and mandibular first molar tooth measurements in dogs: relationship of radiographic height to body weight

Height measurements of the mandible and the mandibular first molar tooth were obtained from 234 dogs. Statistical analysis was performed to determine possible associations between these measurements and body weight, sex, age, and body condition. There was a statistically significant association between the mandible: mandibular first molar tooth height measurement ratio and body weight (p < 0.0001) in all body weight groups. Small dogs had proportionally larger mandibular first molar teeth relative to mandibular height compared with larger dogs. This relationship may contribute to an increased susceptibility in small dogs for periodontitis and subsequent tooth loss. There was no statistically significant association between the mandible: mandibular first molar tooth height measurement ratio and other parameters evaluated in this study.     

Changes to daily feed intake during the laying period alters embryonic MSTN and MYOG gene expression in genetically fat and lean lines of chickens

1. Broiler breeders are unable to self-regulate feed intake to a level that permits reproductive function and restricted feeding is normal for broiler parent stock. The aim of this study was to determine whether myostatin (MSTN) and myogenin (MYOG) mRNA expression could be altered in relation to differences in body composition of the embryos and the hen’s diet.

2. A 2 × 2 factorial experiment was conducted with two dietary intake levels (100% and 75% of nutrition recommendation) and two broiler genotypes (Fat line and Lean line). Hens (384 of each line) were randomly divided at 23 weeks of age into 4 treatments, with each treatment represented by 12 replicates of 16 birds each. The experiment started when the rate of lay reached 5% and continued until 54 weeks of age.

3. There were significant effects of line and dietary intake, and interactions between them on MSTN and MYOG mRNA expression levels in embryonic tissues. The trend in MSTN mRNA expression level over the embryonic period was similar between lines. Low daily feed intake did not alter the trend in MSTN mRNA expression levels in either line, but significantly changed the peak values. MYOG mRNA expression varied by line and over time, with a delay in the Lean line. Low daily feed intake influenced the trend in MYOG mRNA expression levels in both lines and delayed its onset.     

Comparison of susceptibility to stress in two genetic lines of turkey broilers,BUT-9 and Big-6

The aim of the study was to compare the level of susceptibility to stress in two broiler turkey lines-BUT-9 and Big-6. The experiment was performed on 120 turkey toms aged ca. 8 weeks. Each of the genetic lines was represented by 60 birds divided into 4 groups--one control and three experimental ones, 15 birds in each. The open field test was conducted in the control groups (not exposed to any stress) in order to determine the motor activity of turkeys. The other groups were subjected to the stress of transport, crowding and overheating. When the experiment was over, following indices were determined in blood plasma obtained from all the birds: the concentration of corticosterone, adrenaline and noradrenaline, the level of glucose, cholesterol, total lipids and triglycerides as well as the activity of creatine kinase. The study revealed that the lighter and slower growing BUT-9 turkeys showed a higher resistance to stress than the Big-6. They were characterised by higher motor activity, a higher initial level of catecholamines in blood and heavier adrenals. The increase in corticosterone was much lower in these birds in response to stress. A lower reactivity was also observed in the biochemical indices (the level of cholesterol, triglycerides and glucose and the activity of creatine kinase). This confirms that BUT-9 turkeys are less sensitive to adverse environmental effects than are the Big-6, an interesting feature for poultry production.