OF THE LONGEST BACK MUSCLE OF KEMEROVO PIGS AND THEIR CROSSBREEDS WITH COMMERCIAL BREEDS

The results of the assessment of the amino acid profile of the longest muscle of the back of the Kemerovo breed of pigs and its two-breed and three-breed crosses with commercial breeds are presented. The largest amount of amino acids is found in the meat of purebred animals in comparison with two- and threebreed animals. In terms of the content of such amino acids as phenylalanine, aspartic acid, serine, glutamic acid, purebred animals significantly exceeded hybrids. It was shown that the studied groups of animals for all amino acids exceeded the FAO reference values, with the exception of lysine. The influence of gender on the amino acid composition of meat in purebred animals was revealed, since boars significantly exceeded pigs in 8 amino acids out of 17 studied. Reliable correlation coefficients were established between the content of a number of amino acids in meat samples, which coincide in all groups of pigs.

Polymorphism in the ovine keratin-associated protein gene KRTAP7-1 and its association with wool characteristics

The keratin-associated proteins (KAPs) are structural components of wool fibers and variation in the genes encoding the KAPs can affect wool traits. In this study, sequence variation in the ovine KAP7-1 gene (KRTAP7-1) was investigated in 222 sheep across 5 different Pakistani breeds and breed crosses. Two previously identified variants (A and B) of the KRTAP7-1 coding sequence were identified. The frequency of the genotypes AA and AB was 76% and 23%, respectively, and that of BB was 1%. The association of sequence variation with various wool traits and measurements included yield (the proportion of greasy fleece weight that is clean fleece), mean staple length (MSL), wool bulk, mean fiber diameter, fiber diameter SD, the coefficient of variation of fiber diameter, medullation, the SD of medullation, the coefficient of variation of medullation, fiber opacity, the SD of opacity, and the coefficient of variation of opacity. Variation in KRTAP7-1 was found to be associated with yield (P = 0.017). The adjusted mean yield of sheep of genotype AA (n = 169) was 79.9 ± 2.72%, while that of genotype AB (n = 51) was 81.9 ± 3.37%. There was also an association between variation in KRTAP7-1 and MSL (P = 0.024), with sheep of genotype AA (n = 169) having an adjusted mean MSL of 47.3 ± 0.57 mm compared with sheep of genotype AB (n = 51, 50.9 ± 0.65 mm). Yield and MSL are both important wool production traits, hence variation in KRTAP7-1 needs to be further investigated in more sheep of differing breed.

Crossbreeding effects on growth and efficiency in beef cow–calf systems: evaluation of Angus, Caracu, Hereford and Nelore breed direct, maternal and heterosis effects

The objective of this study was to determine breed additive and heterosis effects on growth curves, total milk yield (TMY), calf weaning weight (WW), predicted energy intake (EI), and cow efficiency (CE) of purebred and crossbred beef cows raised in Southern Brazil. The data were from 175 purebred and crossbred cows representing eight genetic groups: Angus (A), Hereford (H), Nelore (N), A × H (AH), H × A (HA), A × N (AN), N × A (NA), and Caracu (C) × A (CA). Growth of the cows was modeled using the nonlinear Brody function and machine milking was used to assess TMY. WW was linearly adjusted to 210 d. EI was predicted with an equation in which the independent variables were estimates of parameters of the Brody function and TMY. The ratio of WW to EI estimated CE. Taurine–indicine heterosis effects were significant for all traits, and greater than those for taurine breed crosses. In general, crossbred cows were heavier at maturity, matured earlier, produced more milk, weaned heavier calves, and were predicted to consume more energy. Thus, they were more efficient than purebred cows, despite their greater predicted feed intake. Among the purebreds, A cows matured most rapidly, weighed the least at maturity, produced the most milk, weaned the heaviest calves, were predicted to consume the least energy; and were therefore most efficient among the breeds that were evaluated. These results are useful as inputs to bioeconomic models that can be used to predict productive and economic outcomes from crossbreeding and to facilitate recommendations for beef producers of southern Brazil and other similar subtropical climatic regions.

The share of tissues in the pig round depending on the genotype, gender and season

The study included 201 offspring (108 castrated males and 93 females) of Landrace (L), Large White (LW) and Pietrain (P) sires. The studied animals were of following genotype: Landrace (L; n = 48); two breed crosses with 50:50 share of parental breeds (LWxL, n=32; and PxL, n=23), two breed crosses with 75% of paternal breed [Lx(?LWxL), n=35] and [LWx(?LxWL) n=38] and three breed crosses [Px(?LWxL) n=25]. Animals included in this study were born during four seasons: winter (n=38), spring (n=65), summer (n=40) and autumn (n=58). Studies have shown that, at an average weight of warm carcass side of 81.20 kg, the highest average values for the weight of round (RW; 10.204 kg), the weight of intermuscular fatty tissue (RINT; 0.478 kg), bone tissue (RBT; 0.850 kg) and muscle tissue (RMT, 7.552 kg) in the round, were established in three-breed crosses of Px (LWxL) genotype compared to other genotypes. The least skin and subcutaneous fatty tissue (RST; 1.269 kg) was recorded in two breed crosses PxL. They had less skin and subcutaneous fatty tissue by 454 g and 467 grams, respectively, compared to two breed crosses (LWxL) and LWx (?LxLW). Research has shown that there is a genotype on a farm that gives more muscle tissue in the round by 1.521 kg [Px (?LWxL): LWx (?LWxL)] with the same weight of warm carcass side, which is a very large difference. With the same average weight of warm carcass side, female animals had higher average weight of the round and yield of muscle tissue compared to male castrated animals. The effect of genotype (P<0.001) on all investigated traits was recorded, also the effect of the season of birth on the skin and subcutaneous fat tissue and on the weight of intermuscular fat in the round was recorded. The effect of sex/gender was significant (P<0.01) on the weight of skin and subcutaneous fat and on the weight of the muscle tissues in the round but no significant effect on other tested properties (P> 0.05) was observed.

NUTRITIONAL VALUE OF TWOYEARLING CARP OF DIFFERENT CROSS-BREEDS

One of the important fields of carp breeding work is improvement of the commercial traits of created carp breeds or cross-breed commercial crosses. The main indicator determining the value of commercial fish is edible carcass yield depending on the interior (relative weight of carcass edible parts) and the exterior (high spin, ratios of head and body girth, type of scale) indices. The paper presents the results of researches on interior indicators (body parts ratio) of twoyearlings of two-breed crosses obtained from crossing of adapted fourth generation imported breeds grown in Belarus with carp lines of Belarusian selection. The edible part of carcass size varied from 60.7 % (three prim x fresinet) to 66.7% (GermançLahvinsk scaly), averaging 64.0 % in the two-breed crosses studied. Compared with the average population yield of carcass in twobreed crosses, statistically significant advantages were determined in combinations of crossing with German carp. In this regard, quite high indicators were also observed in combinations with the Yugoslav carp, where it was used as the maternal component of crosses, and in combinations obtained from crossing the Mirror Isobelin carp with a Butterfly breed. Based on comprehensive assessment of interior indicators, a number of crosses have been determined with increased nutritional value of carcasses, among which the maximum nutritional value was shown by the cross Germançthree prim. The obtained data are of practical importance for creation of industrial hybrids with attractive commercial traits.

Production, carcass characteristics and valuable cuts of purebred Simmental and Simmental × beef breed crossbred bulls in Finnish beef cattle population

The objective of the present research was to study the potential for improvement of growth and carcass traits through Simmental (Si) × beef breed crossbreeding compared to purebred Si bulls in Finnish beef cattle population. The data collected from Finnish slaughterhouses included observations of 6 224 purebred Si bulls plus Si × beef breed crosses. For estimating valuable cuttings, a separate dataset including in total 314 bulls was also collected. The estimated average daily carcass gain of the purebred Si bulls was 686 g/d and it improved by 3 and 6% with Si×Blonde d’Aquitaine and Si×Charolais crossbreds, respectively. Carcass conformation improved by using Blonde d’Aquitaine, Limousin and Charolais crossbreeding compared to the pure Si bulls. Si×British breed crossbreds (Angus and Hereford) had poorer carcass gain and produced poorer conformed carcasses compared to purebred Si bulls. Furthermore, the yield of subcutaneous fat was higher in the Si×Angus and Si×Hereford bulls than in the purebred Si bulls.