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991.
992.
Goat milk casein proteins (αS1, αS2, β and κ) are encoded by four loci (CSN1S1, CSN1S2, CSN2 and CSN3, respectively) clustered within 250 kb in chromosome 6. In this study, 159 Murciano-Granadina goats were genotyped for 48 SNPs within the entire casein region. Phenotypes on milk yield and components were obtained from 2,594 dairy registries. Additive and dominance effects on milk composition and quality were studied using non-parametric tests and principal component analysis to prevent SNPs multicollinearity. Two deletions in exon 4 (CSN1S1 and CSN3), one in exon 7 (CSN2) and one in exon 15 (CSN1S2) have been found at frequencies ranging from 0.12 to 0.50. Bonferroni-corrected significant SNP additive and dominance effects were found for milk yield, fat, protein, dry matter and lactose, and somatic cells. Exons 15 and 7 were significantly associated with milk yield and components except for lactose and somatic cells, while exon 4 was significantly associated with milk yield and components except for protein and dry matter. SNPs' associations with somatic cells were less frequent and weaker than those with milk yield and components. As caseins increase, somatic cells decrease, reducing milk enzymatic activity and consumption suitability. Hence, including molecular information in breeding schemes may promote production efficiency, as selecting against undesirable alleles could prevent the compromises derived from their dominance effects.  相似文献   
993.
In Brazil, water buffaloes have been used to produce milk for mozzarella cheese production. Consequently, the main selection criterion applied for the buffalo genetic improvement is the estimated mozzarella yield as a function of milk, fat and protein production. However, given the importance of reproductive traits in production systems, this study aimed to use techniques for identifying genomic regions that affect the age at first calving (AFC) and first calving interval (FCI) in buffalo cows and to select candidate genes for the identification of QTL and gene expression studies. The single-step GBLUP method was used for the identification of genomic regions. Windows of 1 Mb containing single-nucleotide polymorphisms were constructed and the 10 windows that explained the greatest proportion of genetic variance were considered candidate regions for each trait. Genes present into the selected windows were identified using the UOA_WB_1 assembly as the reference, and their ontology was defined with the Panther tool. Candidate regions for both traits were identified on BBU 3, 12, 21 and 22; for AFC, candidates were detected on BBU 6, 7, 8, 9 and 15 and for first calving interval on BBU 4, 14 and 19. This study identified regions with great contribution to the additive genetic variance of age at first calving and first calving interval in the population of buffalo cows studied. The ROCK2, PMVK, ADCY2, MAP2K6, BMP10 and GFPT1 genes are main candidates for reproductive traits in water dairy buffaloes, and these results may have future applications in animal breeding programs or in gene expression studies of the species.  相似文献   
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The most prevalent causes of death in racehorses are musculoskeletal injuries, causing ~83% of deaths within the racing industry in California and elsewhere. The vast majority of these injuries have preexisting lesions that predispose to fatal injury. A 4-y-old Thoroughbred colt suffered an acute suspensory apparatus failure, including biaxial proximal sesamoid bone fractures of the right front fetlock, causing loss of support of the fetlock joint and consequent fall with fractures of the cervical and sacral spine. Cervical fracture caused spinal cord damage that resulted in sudden death. A preexisting lesion in the medial proximal sesamoid bone likely predisposed to complete fracture of this bone and fetlock breakdown. Interestingly, a comparable osteopenic lesion was present in the intact medial proximal sesamoid bone of the left forelimb, which is consistent with bilateral repetitive overuse injury in racehorses. The morphologic features of the cervical and sacral spine fractures were compatible with acute injury; no evidence of preexisting lesions was seen. Most likely, these acute vertebral fractures occurred as a result of the horse falling. This case emphasizes the importance of performing a detailed autopsy in horses that suffer an appendicular musculoskeletal injury, particularly in fatal cases when the horse dies following a leg injury.  相似文献   
998.
This study estimated the net macro and micromineral requirement from the 48 male uncastrated lambs (24 growing male Santa Inês and 24 growing male Morada Nova hair sheep), with initial weights of 21.7 ± 1.2 kg and 20.8 ± 0.8 kg using the comparative slaughter method. The experimental diet consisted of 30% forage (Buffel—Cenchrus ciliaris (L) hay) and 70% concentrate (corn grain 43.5%, soybean meal 22.0%, vegetable oil 3.0% and mineral supplement 1.5%). The experimental design was a completely randomized with two breeds, four weights, and six replicate. Mineral requirements sufficient to promote weight gain in Santa Inês sheep ranged from 1.75 to 1.03 g Ca, 1.01 to 0.61 g of P, 0.38 to 0.21 g of K, 0.38 to 0.16 of Na, 0.10 to 0.06 Mg, 28.5 to 16.0 mg of Fe, 6.14 to 3.22 mg of Cu, and Zn 23.0 to 14.0 mg/kg per unit of empty body weight (EBW) gain. In the Morada Nova breed, the requirements ranged from 1.96 to 0.84 g of Ca, 1.15 to 0.46 of P, 0.39 to 0.19 of K, 0.28 to 0.13 of Na, 0.10 to 0.05 Mg, 26.2 to 12.9 mg of Fe, 5.59 to 2.46 Cu, and Zn 23.6 to 10.3 mg/kg of EBW gain. Mineral requirements varied mainly in accordance with the proportion of bone mass and fat concentration in the carcass, which were influenced by the slaughter weight of the animals, and therefore should be used in the formulation of dietary mineral supplements.  相似文献   
999.
The objective of this study was to evaluate the influence of the total or partial replacement of Tifton 85 hay (TH) by cassava foliage hay (CH) and/or spineless cactus (SC) on the carcass characteristics and meat quality of confined lambs. Thirty-five Dorper x Santa Inês crossbred lambs were used, with an initial average weight of 16.0 ± 1.9 kg, fed with five treatment diets: 70% TH, 70% CH, 35% TH + 35% CH, 35% TH + 35% SC, and 35% CH + 35% SC. After 90 days of confinement, the animals were slaughtered and the carcass and meat data were compared using the Tukey test at 5%. The partial replacement of TH by SC increased the cold carcass weight by 3.9 kg (p < .05). The proportion of fat (%) increased (p < .05) when TH was replaced by CH + SC. The intensity of red (a*) was lower (p < .05) in the meat of animals fed with CH or CH + SC. It is recommended to partially replace TH with SC, or to replace totally with CH in association with SC.  相似文献   
1000.
The objective of this study was to collect and interpret three-axis acceleration, temperature, and relative humidity data from six locations within commercial transport trailers shipping market-weight pigs. Transport was observed in Kansas (n = 15) and North Carolina (n = 20). Prior to loading, three-axis accelerometers were affixed to six locations on the trailers: top fore (TF), top center (TC), top aft (TA), bottom fore (BF), bottom center (BC), and bottom aft (BA) compartments. Data were post-processed to calculate root-mean-square (RMS) accelerations and vibration dose values (VDV) in the vertical direction and the horizontal plane. These values were compared with exposure action values (EAV) and exposure limit values (ELV), vibration levels deemed uncomfortable and potentially dangerous to humans. Additionally, RMS and VDV were compared among the trailer compartments. The vertical RMS accelerations for all compartments exceeded the EAV for loads measured in Kansas, and for the majority of the compartments measured in North Carolina. Many compartments, specifically the BA compartment from all trips, exceeded the vertical ELV. Regardless of where the data were collected, fewer compartments exceeded the EAV in the horizontal orientation. Only BA compartments exceeded the ELV in the horizontal orientation. There were Area × Level interactions for vertical and horizontal RMS and VDV (P < 0.01). The BF compartment had a greater vertical RMS value than the TF, TC, and BC (P < 0.02) compartments, but did not differ (P = 0.06) from the TA compartment. The vertical RMS of the TA compartment did not differ from the TF, TC, and BC compartments (P > 0.13). The BF compartment had a greater (P = 0.02) vertical VDV value than the TC location, but did not differ from the other locations (P > 0.16). All other locations did not differ in vertical VDV (P > 0.12). The BF compartment had greater horizontal RMS than the TC and TA compartments (P < 0.01), but did not differ from TF and BC compartments (P > 0.12). All other compartments did not differ in horizontal RMS (P > 0.34). All compartments, aside from the BA compartment, did not differ in horizontal VDV (P > 0.19). Vibration analyses indicated the BA compartment had the greatest vertical and horizontal vibrations and a large percentage of the compartments exceed the EAV and ELV, which indicated pigs may have experienced uncomfortable trips that could cause discomfort or fatigue.  相似文献   
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