BackgroundThe domestic pig currently indigenous to the Tibetan highlands is supposed to have been introduced during a continuous period of colonization by the ancestors of modern Tibetans. However, there is no direct genetic evidence of either the local origin or exotic migration of the Tibetan pig.Methods and FindingsWe analyzed mtDNA hypervariable segment I (HVI) variation of 218 individuals from seven Tibetan pig populations and 1,737 reported mtDNA sequences from domestic pigs and wild boars across Asia. The Bayesian consensus tree revealed a main haplogroup M and twelve minor haplogroups, which suggested a large number of small scale in situ domestication episodes. In particular, haplogroups D1 and D6 represented two highly divergent lineages in the Tibetan highlands and Island Southeastern Asia, respectively. Network analysis of haplogroup M further revealed one main subhaplogroup M1 and two minor subhaplogroups M2 and M3. Intriguingly, M2 was mainly distributed in Southeastern Asia, suggesting for a local origin. Similar with haplogroup D6, M3 was mainly restricted in Island Southeastern Asia. This pattern suggested that Island Southeastern Asia, but not Southeastern Asia, might be the center of domestication of the so-called Pacific clade (M3 and D6 here) described in previous studies. Diversity gradient analysis of major subhaplogroup M1 suggested three local origins in Southeastern Asia, the middle and downstream regions of the Yangtze River, and the Tibetan highlands, respectively.ConclusionsWe identified two new origin centers for domestic pigs in the Tibetan highlands and in the Island Southeastern Asian region.
This study compared Amur sturgeon (Acipenser schrenckii) and Chinese sturgeon (Acipenser sinensis) on several biochemical parameters including glucose (GLU), urea, lactate dehydrogenase (LDH-L), activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), direct bilirubin (D.BILI), alkaline phosphatase (ALP), cholesterol (CHOL), triglyceride (TGL), creatinine (CREA), total protein (TP), and total bilirubin (T.BILI). The results showed that there were great differences in these parameters between the two species. The concentrations of GLU, UREA, LDH-L, ALT, AST, D.BILI, ALP, CHOL, TGL, CREA, and T.P for the Amur sturgeon were significantly higher than those for Chinese sturgeon.The T.BILI level of the Amur sturgeon was, however, significantly lower than that for the Chinese sturgeon.
The effects of MS-222 and clove oil on blood biochemical parameters of juvenile Siberian sturgeon (Acipenser baerii) were studied. MS-222 caused higher glucose (GLU) concentrations in anaesthetic test groups than for the control group. Triglyceride (TGL) concentrations of fish in the 140 and 160 mg L )1 groups were also significantly higher than those of other groups. Alanine aminotransferase (ALT) activity in the 140 mg L )1 group was significantly higher than the level in 80, 100 and 120 mg L )1 groups. Aspartate aminotransferase (AST) activity in the 140 mg L )1 group was significantly higher than those in the 100 and 120 mg L )1 groups. Levels of total protein (TP), cholesterol (CHOL) and alkaline phosphatase (ALP) in anaesthetic test groups were not significantly influenced by MS-222. Clove oil did not have significant effects on levels of GLU, TP, CHOL, ALT and ALP. TGL concentration of fish exposed to 180 mg L )1 clove oil was significantly higher than those of the rest anaesthetic groups. AST activities of fish exposed to 120, 150 and 180 mg L )1 were significantly higher than those of 60 and 90 mg L )1 . Overall, TGL and AST could be potentially used as indicators of anaesthetic stress for juvenile Siberian sturgeon. Based on blood biochemical parameters, the appropriate anaesthetic concentrations of MS-222 and clove oil were 80-120 mg L )1 and 60-90 mg L )1 , respectively. Clove oil was a promising alternative to MS-222.
This article describes a study of PIT-tagged sea lamprey (Petromyzon marinus) ascending four fishways comprising three designs at two dams on the Connecticut River, USA. Migration between dams was rapid (median migration rate = 23 km·day−1). Movement through the fishways was much slower, however (median = 0.02–0.33 km·day−1). Overall delay at dams was substantial (median = 13.6–14.6 days); many fish failed to pass (percent passage ranged from 29% to 55%, depending on fishway), and repeated passage attempts compounded delay for both passers and failers. Cox regression revealed that fishway entry rates were influenced by flow, temperature, and diel cycle, with most lampreys entering at night and at elevated flows, but with no apparent effect of sex or length. Overall delay was influenced by slow movement through the fishways, but repeated failures were the primary factor determining delay. These data suggest that although some lamprey were able to pass fishways, they did so with difficulty, and delays incurred as they attempted to pass may act to limit their distribution within their native range.
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