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HI observations of the Magellanic-type spiral NGC 3109, obtained with theseven dish Karoo Array Telescope (KAT-7), are used to analyze its massdistribution. Our results are compared to what is obtained using VLA data.KAT-7 is the precursor of the SKA pathfinder MeerKAT, which is underconstruction. The short baselines and low system temperature of the telescopemake it sensitive to large scale low surface brightness emission. The newobservations with KAT-7 allow the measurement of the rotation curve of NGC 3109out to 32', doubling the angular extent of existing measurements. A total HImass of 4.6 x 10^8 Msol is derived, 40% more than what was detected by the VLAobservations.  The observationally motivated pseudo-isothermal dark matter (DM) halo modelcan reproduce very well the observed rotation curve but the cosmologicallymotivated NFW DM model gives a much poorer fit to the data. While having a moreaccurate gas distribution has reduced the discrepancy between the observed RCand the MOdified Newtonian Dynamics (MOND) models, this is done at the expenseof having to use unrealistic mass-to-light ratios for the stellar disk and/orvery large values for the MOND universal constant a0. Different distances or HIcontents cannot reconcile MOND with the observed kinematics, in view of thesmall errors on those two quantities. As for many slowly rotating gas-richgalaxies studied recently, the present result for NGC 3109 continues to pose aserious challenge to the MOND theory.

KAT-7 Science Verification: Using HI Observations of NGC 3109 to Understand its Kinematics and Mass Distribution