Effects of a second mutant allele (V199I) at the PRKAG3 (RN) locus on carcass composition in pigs

The effect of a second mutant allele (V199I, here denoted rn*) at the PRKAG3 (RN) locus on carcass composition was determined in 334 pigs, entire males and females, from crosses between Swedish Hampshire (H) and Finnish Landrace (L) (H × LH; LH × H; LH × LH). Pigs were classified according to DNA test into the following PRKAG3 genotypes: RN⁻/RN⁻ (23%), RN⁻/rn⁺ (24%), RN⁻/rn* (33%), rn⁺/rn⁺ (8%), rn⁺/rn* (9%) and rn*/rn* (2%). The pigs were slaughtered at a commercial slaughterhouse and assessed 24 h postmortem. Right sides were fabricated into primary wholesale cuts, then further processed into defatted hams and loins, and a subset of hams (n = 122) was dissected into the five major individual muscles. The genotype frequencies for the subsample were RN⁻/RN⁻ (27%), RN⁻/rn⁺ (20%), RN⁻/rn* (35%), rn⁺/rn⁺ (9%), rn⁺/rn* (8%) and rn*/rn* (1%). Weights were recorded for meat and bone in ham and loin, fat in ham, back and shoulder and the individual dissected muscles. The genotype effect was significant (P < 0.05) for estimated lean meat content and the proportions of meat and bone and fat in ham and loin (of carcass weight). Also, the content of meat and bone in ham and loin, in proportion of whole ham and loin, respectively, differed significantly (P < 0.01) between genotypes. Estimated lean meat content was highest for RN⁻/RN⁻ (63.0%) and RN⁻/rn⁺ (63.1%) and lowest in the combined group rn*/⁻ (rn⁺/rn* and rn*/rn*, 61.7%); RN⁻/rn* (62.5%) and rn⁺/rn⁺(62.1%) were intermediate. The same results were found for meat and bone in ham and loin, as a proportion of whole ham and loin, respectively. RN⁻/RN⁻ and RN⁻/rn⁺ did not differ in any trait; however, they produced carcasses with the lowest proportions of fat within loin and the major wholesale cuts (ham, loin and shoulder). The carcass percentage of meat and bone in ham was higher in the three RN⁻/ genotypes (RN⁻/RN⁻, RN⁻/rn⁺ and RN⁻/rn*, P < 0.05) than in the rn*/⁻ group, whereas rn⁺/rn⁺ did not (P > 0.05) differ from any of the other genotypes. RN⁻/rn⁺ and RN⁻/rn* had higher (P < 0.05) proportion of meat and bone in loin compared to the rn*/⁻ group. We conclude that the second mutant allele found at the PRKAG3 (RN) locus, rn*, decreased the lean meat content compared with the two other alleles (RN⁻, rn⁺). The RN⁻/RN⁻ and RN⁻/rn⁺ genotypes were leanest, followed by RN⁻/rn* and rn⁺/rn⁺, and rn⁺/rn* and rn*/rn* were the fattest.     

Percentage of compression wood and specific gravity in blue pine (Pinus wallichiana A. B. Jackson)

Summary There is a positive correlation between the percentage of compression wood and specific gravity in Pinus wallichiana. Where compression wood is present a definite increase in specific gravity occurs in an annual ring, but the influence of compression wood on specific gravity is only local. The first-formed earlywood portion of the ring is the most suitable sampling point for a comparison of specific gravity between rings of the same or different trees.We are thankful to Professor H. O. Agrawal for providing laboratory facilities. The first author is thankful to University Grants Commission (India) for financial assistance.     

Intra-increment variation in specific gravity of wood in blue pine

Summary Intra-increment variation in specific gravity of wood is studied in relation to the types of annual increments in Pinus wallichiana. In the normal annual increments specific gravity increases almost linearly across the ring, displaying minimum value in the first-formed earlywood and maximum value in the last-formed latewood. The occurrence of false rings and that of compression wood in an annual ring causes a localized increase in specific gravity. The change in specific gravity at the false growth ring boundary is slight and gradual, whereas at the true annual rings boundary the change is steep and abrupt. The specific gravity in the first-formed earlywood portion gives the most consistent value as compared to whole earlywood, whole latewood and whole ring when studied around the circumference.The financial support from University Grants Commission (India) is gratefully acknowledged     

Factors affecting the catch and harvest rates of paddlefish downstream of Gavins Point Dam,South Dakota, 2000–2020

Paddlefish, Polyodon spathula (Walbaum), provide an important snagging and bowfishing fishery below Gavins Point Dam in South Dakota. During 2009–2020, snagging catch rates of paddlefish decreased below Gavins Point Dam to presumed “normal” lower pre-2004 levels, while bowfishing catch (harvest) rates significantly increased during 2000–2020. Because Paddlefish are highly migratory, both local (i.e., monthly gauge height, precipitation, and air temperature near Gavins Point Dam) and remote (difference in Mississippi and Missouri River discharge near their confluence) environmental conditions were used to explain variation in snagging catch rates and bowfishing harvest rates. Snagging catch rates were related to October gauge height, whereby deeper water in October led to decreased catch rates below Gavins Point Dam. Bowfishing harvest rates increased significantly after a 2016 regulation change moved the season from July 1 to July 31, and from June 1 to June 30, likely because water clarity was greater in June than in July. Mean annual air temperature and precipitation explained variation in bowfishing harvest rates prior to the 2016 regulation change. Our findings, the first to examine both snagging and bowfishing fisheries below Gavins Point Dam, suggest that local abiotic factors are likely more important than remote discharge for explaining variation in snagging catch rates and bowfishing harvest rates in the channelised Missouri River.     

Splenectomy in the management of primary immune‐mediated hemolytic anemia and primary immune‐mediated thrombocytopenia in dogs

BackgroundCurrent reports about the use of splenectomy for the management of immune‐mediated hemolytic anemia (IMHA) or immune‐mediated thrombocytopenia (ITP) or both in dogs are limited.ObjectivesTo retrospectively describe the use of splenectomy as part of the management for IMHA, ITP, and concurrent IMHA and severe thrombocytopenia (CIST) in dogs. It was hypothesized that splenectomy would be beneficial in allowing for reduction of dose of immunosuppressive drugs or discontinuation in 1 or more of these groups.AnimalsSeventeen client‐owned dogs (7 with IMHA, 7 with ITP, and 3 with CIST) were identified across 7 UK‐based referral hospitals from a study period of 2005 to 2016.MethodsData were collected retrospectively via questionnaires and included information about diagnosis, management and treatment response before and after splenectomy. Based on clinical outcome, treatment with splenectomy as part of the management protocol was classified as either successful or unsuccessful.ResultsSix of 7 dogs with ITP were managed successfully with splenectomy as part of their management protocol (3 complete and 3 partial responses), although 1 subsequently developed suspected IMHA. Of the 7 dogs with IMHA, splenectomy was part of a successful management protocol in 4 dogs (2 complete and 2 partial responses). In the CIST group, 1 case (1/3) responded completely to management with splenectomy as part of the management protocol.Conclusions and Clinical ImportanceSplenectomy was considered successful and well tolerated in most cases of isolated ITP. Whether there is a benefit of splenectomy in cases of IMHA and CIST could not be determined in the current study.     

Double ureters with ureteral ectopia in a domestic shorthair cat

A 5-month-old domestic shorthair cat was presented for evaluation of urinary incontinence since birth. Excretory urography revealed dilated double ectopic ureters draining a hydronephrotic right kidney. Urine culture yielded a pure culture of Klebsiella pneumoniae. The cat was treated initially with bactericidal antibiotics, followed by right-sided nephroureterectomy. The surgery and antibiotic therapy led to complete resolution of urinary incontinence and urinary tract infection. Ureteral duplication is an unusual congenital anomaly that has not been previously reported in the cat.     

Irreconcilable differences: fine-root life spans and soil carbon persistence

The residence time of fine-root carbon in soil is one of the least understood aspects of the global carbon cycle, and fine-root dynamics are one of the least understood aspects of plant function. Most recent studies of these belowground dynamics have used one of two methodological strategies. In one approach, based on analysis of carbon isotopes, the persistence of carbon is inferred; in the other, based on direct observations of roots with cameras, the longevity of individual roots is measured. We show that the contribution of fine roots to the global carbon cycle has been overstated because observations of root lifetimes systematically overestimate the turnover of fine-root biomass. On the other hand, isotopic techniques systematically underestimate the turnover of individual roots. These differences, by virtue of the separate processes or pools measured, are irreconcilable.